#Catalase Antibody

[moleculardepot]

Catalase Polyclonal Antibody

Catalase Polyclonal Antibody Catalog number: B2015336 Lot number: Batch Dependent Expiration Date: Batch dependent Amount: 25 µg Molecular Weight or Concentration: 60 kDa Supplied as: Solution Applications: a molecular tool for various biochemical applications Storage: -20°C Keywords: CAT, catalase, Cell and organelle markers, Peroxisome Marker Grade: Biotechnology grade. All products are highly…

[bostorbio]

Boster Bio Anti-Catalase Antibody Picoband™ catalog # PB9925. Tested in Flow Cytometry, IF, IHC-P, IHC-F, ICC, WB applications. This antibody (catalase antibody) reacts with Human, Mouse, Rat.

[mcatmemoranda]

Going through questions:

Nitroblue tetrazolium testing is used for diagnosis of Chronic Granulomatous Disease (CGD). Normally, neutrophils will turn blue on nitroblue tetrazolium testing because of the respiratory burst in phagolysosomes, but there is no blue color change in CGD because there is no production of oxidative species. CGD is due to an X-linked Recessive NADPH oxidase mutation. NADPH oxidase catalyzes production of reactive oxygen species, which kill bacteria. NADPH also catalyzes activation of granule proteases, like elastase, in phagosomes. Mutation of NADPH oxidase gene-> deficient NADPH oxidase-> neutrophils and macrophages can't kill bacteria that they phagocytose. This leaves pts susceptible to recurrent fungal and bacterial infections, especially catalase + bugs (staph aureus, serratia marcenscens, aspergillus, burkholderia cepacia, and nocardia). The skin, lungs, liver, and lymph nodes are often infected in these pts. For diagnosis of CGD, you want to measure neutrophil superoxide production with either the Nitroblue Tetrazolium (NBT) test or with flow cytometry using dihydrorhodamine (DHR). The DHR test is better.

IL-12 presented to naive helper T cells by macrophages causes naive helper T cells to differentiate into Th1 cells, which release IFN-gamma; IFN-gamma activates cytotoxic CD8+ T cells and macrophages to kill intracellular pathogens. Mycobacterium is an intracellular pathogen that is killed this way. People with IL-12 deficiency can't mount a cell-mediated immune response and are susceptible to mycobacterium infection. Interferon gamma is given to treat these pts.

In OnlineMedEd, Dustyn said that in graft vs host disease, the lymphocytes in the donor tissue trigger the recipient to make antibodies against the recipient. In this question I just answered, it says that T lymphs in the donated organ are sensitized to the recipient's MHC Ag and then they attack the host's tissues. Donor T cells from the donated organ go into the host's tissues, become sensitized to the host's MHC antigens, and then the donor CD4+ and CD8+ T cells destroy host cells. The GI tract, the skin, and the liver are usually affected. The pt can get a rash that includes the palms and soles.

IL-2 is made by CD4+ helper T cells and activates more CD4+ helper T cells, cytotoxic CD8+ T cells, Natural Killer cells, monocytes, and B cells. T cells and natural killer cells activated by IL-2 kill renal cancer and metastatic melanoma. I posted a picture showing how immumosuppressants work. So IL-2 causes activation of macrophages and NK cells, proliferation and differentiation of helper T cells, growth and secretion of IFN-gamma from T cells, and proliferation of B cells.

Macrophages, B cells, dentritic cells = Antigen-Presenting Cells (APCs); they have MHC Class II, which they use to present angtigens to CD4+ helper T cells.

Type IV (T cell-mediated/delayed type) HSR = T lymphs release cytokines that cause induration 24-48 hours after exposure to the Ag. So cytokines, CD8+ T cells, and macrophages cause the type IV HSR. Poison ivy is a type IV HSR.

Poison ivy, poison oak, and poison sumac make urushiol, which attaches to proteins (haptenization)-> T-cell mediated immune response. CD8+ T cells destroy keratinocytes with the haptenated proteins.

Accumulation of ADA-> destruction of lymphocytes. Adenosine is converted to inosine by adenosine deaminase (ADA). ADA also catalyzes the conversion of deoxyadenosine to deoxyinosine. If ADA is absent, then deoxyadenosine is converted to dATP and that causes lymphocyte apoptosis. Hairy cell leukemia is a lymphocyte cancer, which can be treated with ADA inhibitor (cladribine). ADA deficiency also causes SCID, which is lack of B and T cells.

Hib vaccine is made with the polysaccharide capsule of Hib conjugated to tetanus toxoid carrier protein (or N. meningitidis outer membrane protein). The protein conjugation elicits T cell mediated immune response-> B cell activation-> memory B cells, which causes long term immunity. The capsule isn't effective at eliciting the T cell response in pts younger than 2 years old because their humoral immunity is underdeveloped. So conjugating the capsule polysaccharide to a protein increases the humoral response against the capsule via T cell activation. T cells-> B cell stimulation-> memory B cells.

Steroids cause neutrophil count to increase because it prevents them from marginating (lining up against the walls of blood vessels). Steroids can cause hypomania and psychosis. Steroids decrease basophils, eosinophils, lymphs, and monocytes.

Mycophenolate inhibits IMPDH, which prevents conversion of inosine monophosphate to guanosine monophosphate. This prevents DNA and RNA synthesis in lymphs. Mycophenolate is used to prevent transplant rejection.

Eosinophils release major basic protein, which causes the induration that occurs 2 to 10 hours after exposure to an allergen. It's responsible for the late phase of a dermatologic type I HSR and is IgE-mediated. Major basic protein damages tissue. Wheal and flare is the early phase of a type I HSR in the skin. The late phase induration of the skin is due to release of major basic protein from eosinophils. Contrast this with type IV HSR, which is T cell-mediated and takes days, rather than hours, to develop.

Classical complement pathway starts with C1 binding to 2 IgGs or 2 IgMs. C1 binds Fc region of heavy chain near the hinge point. After IgM binds to an antigen, the C1 binding site is revealed and C1 can bind to it, activating complement.

There are more steps in WBCs leaving the vessels to get to the cytokines than what he mentioned in OnlineMedEd. The steps of inflammation are: margination, rolling, activation, tight adhesion and crawling, and transmigration. He grouped it differently in the video. Rolling is when the neutrophil slows down via interaction of its sialylated carbohydrate groups with selectins on endothelial cells. For example, sialyl Lewis X or PSGL-1 on neutrophils with selectins on endothelial cells. Then integrins on the endothelial surface (ICAM-1) stop the WBCs. In the tight adhesion and crawling phase of inflammation, CD18 beta 3 integrins on neutrophils bind to ICAM on endothelial cells. Then PECAM lets neutrophils slide through the spaces between the blood vessel wall cells during transmigration. Leukocyte adhesion deficiencies (LADs) prevent leukocytes from migrating from the blood to the site of cytokine release. LAD type 1 = no CD18-> no beta 2 intergins-> skin infections with no pus and delayed separation of umbilical cord.

C1 inhibitor deficiency leads to cleavage of C2 and C4-> excessive activation of complement system; also causes angioedema and GI symptoms.

Hemolytic Disease of the Fetus and Newborn (HDFN) occurs when the mom has type O blood and thus makes IgG against type A and B blood. If this mom's baby has type A, B, or AB blood, her IgG can diffuse across the placenta and cause hemolysis in the baby. But moms with type A or B blood make IgM antibodies (anti-B if the mom has type A blood; anti-A if the mom has type B blood), which can't cross the placenta, and thus don't cause hemolysis in the newborn. In contrast to Rh disease, HDFN can occur during the first pregnancy because the mom makes anti-B and anti-A IgGs in response to similar antigens that are encountered early in life.

Leukotriene B4 causes neutrophil chemotaxis.

[feiyuebio-lottieshi]

Bovine Catalase (CAT) ELISA Kit

Bovine CAT(Catalase) ELISA Kit Basic Information

Feiyue's Bovine CAT(Catalase) ELISA Kit is an ELISA reagent for detection of CAT(Catalase), plasma or cell with sensitivity, specificity and consistency.

CAT(Catalase) Introduction

Catalase is a common enzyme found in nearly all living organisms exposed to oxygen (such as bacteria, plants, and animals) which catalyzes the decomposition of hydrogen peroxide to water and oxygen. It is a very important enzyme in protecting the cell from oxidative damage by reactive oxygen species (ROS). Likewise, catalase has one of the highest turnover numbers of all enzymes; one catalase molecule can convert millions of hydrogen peroxide molecules to water and oxygen each second.

Bovine CAT(Catalase) ELISA Kit Test method

This ELISA kit uses the Sandwich-ELISA principle. The micro plate provided in this kit has been pre-coated with an antibody specific to Bovine CAT. Standards or samples and Horseradish Peroxidase (HRP) labeled detection antibody specific for Bovine CAT are added to the plate wells together and incubated. After washing off unbound material, TMB substrate solution is added to all wells and incubated. An enzyme-catalyzed reaction generates a blue color in the solution, thereafter, stop solution is added to stop the substrate reaction and the color turns yellow. The yellow solution is read at a wavelength of 450nm. The concentration of Bovine CAT in the samples is then calculated from the OD value by establishing a standard curve.

www.feiyuebio.com

lottie@feiyuebio.com

[biomedgrid]

Biomed Grid | Biological Applications of Platinum-Based Nanoclusters

Introduction

Nanomaterials are materials which exist on a nanometer scale in at least one dimension. These materials, especially noble metal nanoparticles, exhibit distinct physical and chemical properties compared to their bulk counterparts due to the high surface to volume ratio and the quantum confinement effect, which make them highly compatible in materials science and biological applications. When the sizes are less than 2nm, nanoparticles become nanoclusters, whose electronic structures change from a continuous band into a discrete molecular-like orbital levels. Such unique electronic properties combined with the good biocompatibility and photostability, suggesting promising potentials of these noble metal nanoclusters for biological applications [1]. This mini review will focus on Platinum (Pt) nanoclusters and the corresponding biological applications specifically in biological imaging, enzymelike properties and cancer treatment.

Discussion

Biological Imaging

Biological imaging provides unique advantages in cancer identification and drug delivery [2]. One of the most critical factors for successful biological imaging is the use of stable, biocompatible and sensitive markers [3]. Traditional markers including organic dyes and fluorescent proteins often experience stability concerns for long-term experiments. Quantum dots markers have disadvantages such as biocompatibility issues for in vivo use. In contrast, Pt nanoclusters illustrate high sensitivity in long-term experiments and biocompatibility, making them highly suitable for biological imaging. For example, it has been reported that Pt nanoclusters attached by polyamine could be used for staining in hematopoietic system [4]. In addition, cell membranes have been imaged by blue mercaptoacetic acid protected Pt nanoclusters, where the antibody receptors were expressed [5].

Enzyme-Like Activities

Except for the excellent photoluminescence properties for bioimaging, protein capped Pt nanoclusters have also illustrated enzyme-like properties, i.e. peroxidase, oxidase and catalase [6]. Peroxidases are type of enzymes that reduce the lipid peroxide or hydrogen peroxide, and high peroxidase activities of Pt-based nanoclusters have been reported by Wei and coworker [7]. Based on the inhibition behavior of the peroxidase enzymatic activities between Pt and Hg, Pt nanoclusters have been proposed and utilized for the detection of toxic metal ions [8]. Oxidases are type of enzymes that promote oxidation by molecular Oxygen (O2).

Tseng and coworkers have shown that lysozyme ligand protected Pt nanoclusters could catalyze the oxidation reactions of organic substances such as dopamine and the degradation mechanism of organic pollutants by Pt nanoclusters have also been proposed [9]. Catalases are type of enzymes that decompose hydrogen peroxide into O2 and H2O. Nie, et al. have reported that the Platinum-ferritin nanoclusters could catalyze the decomposition of H2O2, which further reduce the 5-Diethoxyphosphoryl-5-methyl- 1-pyroline-N-oxide (DEPMPO)/OH˙ adduct signal in a H2O2/UV DEPMPO spin trap system [10].

Cancer Treatment

Platinum-Based drugs are widely used compounds for treatments of head, neck, cervical and lung cancers [11]. DNAPt adducts produced by cisplatin and other analogues are wellknown for their anti-tumor activities decades ago. However, these drugs demonstrate little effect on breast, liver, and prostate cancers, as well as similar tumor sensitivity and susceptibility to tumor resistance. To overcome this, demethylcantharidin has been employed to introduce the selectivity of anti-tumor behavior towards liver cancer cells [12]. Additionally, demethylcantharidinplatinum complexes have also shown to be free from cross resistance with cisplatin. Chien et al. have reported a dendrimercapped Pt nanocluster for targeting breast cancer cells [13]. Xia et al. have demonstrated polypeptide protected Pt nanoclusters could accelerate the release of Pt ions and overcome the cisplatin resistance problems [14].

Conclusion

Due to ultra-small size, Pt nanoclusters have illustrated distinct electronic properties compared to the bulk materials. Combined with the good biocompatibility and photoluminescence, Pt nanoclusters have demonstrated exciting potential for biological applications such as, biological imaging, enzyme-like property and cancer treatment. Future directions include synthesizing Pt nanoclusters with improved florescence character, enhancing enzyme activities and preparation of new ligand groups for targeting tumor cells with lower resistivity.

Read More About this Article: https://biomedgrid.com/fulltext/volume6/biological-applications-of-platinum-based-nanoclusters.001094.php

For more about: Journals on Biomedical Science :Biomed Grid | Current Issue

[halocantik]

How honey kills bacteria

The FASEB Journal

•

Research Communication

How honey kills bacteria

Paulus H. S. Kwakman,* Anje A. te Velde,† Leonie de Boer,* Dave Speijer,‡ Christina M. J. E. Vandenbroucke-Grauls,*,§ and Sebastian A. J. Zaat*,1

*Department of Medical Microbiology, Center for Infection and Immunity Amsterdam, †Laboratory of Experimental Gastroenterology and Hepatology, and ‡Department of Medical Biochemistry, Academic Medical Center, University of Amsterdam, Amsterdam; and §Department of Medical Microbiology and Infectious Diseases, Vrije Universiteit Medical Center, Amsterdam,

The Netherlands

  ABSTRACT         With the rise in prevalence of antibiotic- resistant bacteria,

honey

is increasingly valued for its antibacterial activity. To characterize all bactericidal factors in a medical-grade honey, we used a novel approach of successive neutralization of individual honey bactericidal factors. All bacteria tested, including

Bacillus subtilis

, methicillin-resistant

Staphylococcus au-

reus

, extended-spectrum J3-lactamase producing

Esche-

richia coli

, ciprofloxacin-resistant

Pseudomonas aerugi-

nosa

, and vancomycin-resistant

Enterococcus faecium

, were killed by 10 –20% (v/v) honey, whereas >40% (v/v) of a honey-equivalent sugar solution was required for similar activity. Honey accumulated up to 5.62 ±

0.54 mM H2O2 and contained 0.25 ± 0.01 mM methyl-

glyoxal (MGO). After enzymatic neutralization of these two compounds, honey retained substantial activity. Using

B. subtilis

for activity-guided isolation of the additional antimicrobial factors, we discovered bee defensin-1 in honey. After combined neutralization of H

2

O

2

, MGO, and bee defensin-1, 20% honey had only minimal activity left, and subsequent adjustment of the pH of this honey from 3.3 to 7.0 reduced the activity to that of sugar alone. Activity against all other bacteria tested depended on sugar, H

2

O

2

, MGO, and bee defensin-1. Thus, we fully characterized the antibacterial activity of medical-grade honey.—Kwak- man, P. H. S., te Velde, A. A., de Boer, L., Speijer, D., Vandenbroucke-Grauls, C. M. J. E., Zaat, S. A. J. How honey kills bacteria.

FASEB J.

24, 2576 –2582 (2010).

www.fasebj.org

 Key Words: antibacterial agents · drug resistance · isolation and purification · methicillin-resistant Staphylococcus aureus

· peptides

 Honey has been renowned for its wound-healing properties since ancient times (1). At least part of its positive influence is attributed to antibacterial proper- ties (2, 3). With the advent of antibiotics, clinical application of honey was abandoned in modern West-

The potent in vitro activity of honey against antibiotic- resistant bacteria (6, 7) and its successful application in treatment of chronic wound infections not re- sponding to antibiotic therapy (3) have attracted considerable attention (8 –10).

The broad spectrum antibacterial activity of honey is multifactorial in nature. Hydrogen peroxide and high osmolarity— honey consists of ~80% (w/v) of sugars— are the only well-characterized antibacterial factors in

honey (11). Recently, high concentrations of the anti- bacterial compound methylglyoxal (MGO) were found specifically in Manuka honey, derived from the Manuka tree (Leptospermum scoparium) (12, 13). Until now, no honey has ever been fully characterized, which ham- pers clinical application of honey.

Recently, we determined that Revamil medical-grade honey, produced under standardized conditions in greenhouses, has potent, reproducible bactericidal ac- tivity (14). In the current study, we identified all bactericidal factors in the honey used as source for this product and assessed their contribution to honey bac- tericidal activity.

To accomplish this, we used a novel approach of successive neutralization of individual honey bacteri- cidal factors combined with activity-guided identifica- tion of unknown factors.

  MATERIALS AND METHODS

 Honey

 Unprocessed Revamil source (RS) honey was kindly provided by Bfactory Health Products (Rhenen, The Netherlands). RS honey has a density of 1.4 kg/L and contains 333 g/kg glucose, 385 g/kg fructose, 73 g/kg sucrose, and 62 g/kg maltose. To study the contribution of the sugars to the bactericidal activity of honey, a solution with a sugar compo- sition identical to that of the honey was prepared.

ern medicine, although in many cultures, it is still used                                  

(4). These days, however, abundant use of antibiotics has resulted in widespread resistance. With the devel- opment of novel antibiotics lagging behind (5), alter- native antimicrobial strategies are urgently needed.

1 Correspondence: Department of Medical Microbiology, Academic Medical Center, Meibergdreef 15, 1105 AZ Amster- dam, The Netherlands, E-mail: s.a.zaat@amc.uva.nl

doi: 10.1096/fj.09-150789

Microorganisms

 Bactericidal activity of honey was assessed against the labora- tory strains Bacillus subtilis ATCC6633, Staphylococcus aureus 42D, Escherichia coli ML-35p (15), and Pseudomonas aeruginosa PAO-1 (ATCC 15692), and against clinical isolates of methi-

cillin-resistant S. aureus (MRSA), vancomycin-resistant Entero- coccus faecium (VREF), extended-spectrum [3-lactamase-pro- ducing E. coli (E. coli ESBL) and ciprofloxacin-resistant

P. aeruginosa (CRPA).

aliquots of undiluted and 10-fold serially diluted incubations were plated on blood agar. Bacterial survival was quantified after overnight incubation at 37°C. The detection level of this assay is 100 CFU/ml.

To assess the contribution of H2O2 to the bactericidal activity of honey, bovine liver catalase (Sigma) was added to a final concentration of 600 U/ml. A catalase stock solution was prepared according to the manufacturers’ instructions in 50 mM phosphate buffer (pH 7.0). The addition of 0.25% (v/v) of this catalase stock solution reduced the amount of H2O2 to undetectable levels at all honey concentrations tested and did

Determination of H O

concentration in honey

not affect bacterial viability.

2     2                                                                                                                     Sodium polyanetholsulfonate (SPS) (Sigma) was added to neutralize cationic bactericidal components (19) at a final

Hydrogen peroxide concentrations in honey were deter-

mined quantitatively using a modification of a method de- scribed previously (16). Undiluted and 10-fold diluted sam-

ples of honey (40 µl) were mixed in wells of microtiter plates with 135 µl reagent, consisting of 50 µg/ml O-dianisidine (Sigma, St. Louis, MO, USA) and 20 µg/ml horseradish peroxidase type IV (Sigma) in 10 mM phosphate buffer (pH

6.5). O-dianisidine and peroxidase solutions were freshly prepared from a 1 mg/ml stock in demineralized water and from a 10 mg/ml stock in 10 mM phosphate buffer (pH 6.5), respectively. After 5-min incubations at room temperature,

reactions were stopped by addition of 120 µl6MH SO , and

concentration of 0.025% (w/v). The incubation buffer did not affect the pH of the concentrations of honey used in our experiments.A1M NaOH solution was used to titrate honey solutions to pH 7.0.

 Agar diffusion assay

 To assess antibacterial activity of fractionated honey, an agar diffusion assay was used (20). In brief, a B. subtilis inoculum suspension was prepared as described for the liquid bacteri- cidal assay. Bacteria (107 CFU) were mixed with 20 ml

2    4             nutrient-poor agar [0.03% (w/v) TSB in 10 mM sodium

absorption at 540 nm was measured. Hydrogen peroxide concentrations were calculated using a calibration curve of 2-fold serial dilutions of H2O2 ranging from 2200 to 2.1 µM.

 MGO neutralization assay

 Reduced glutathione (Sigma) was added to diluted honey to a final concentration of 15 mM, and conversion of MGO to S-d-lactoyl-glutathione (SLG) was initiated by addition of 0.5 U/ml glyoxalase I (Sigma). The amount of MGO converted was determined using the extinction coefficient of SLG of

3.37 mM-1 at 240 nm (17). Thus, we determined that up to 10 mM of exogenous MGO added to 40% honey was com-

pletely converted, and that undiluted RS honey contained

0.25 0.01 mM of MGO.

 Antibee defensin-1 polyclonal antibody

 An affinity-purified polyclonal antibee defensin-1 antibody was purchased from Eurogentec (Seraing, Belgium). The N-terminal part of bee defensin-1 is hydrophobic and con- tains 3 disulfide bonds, whereas the hydrophilic C-terminal region lacks cysteine residues (18). Therefore, rabbits were immunized with a synthetic peptide corresponding to the C terminus of bee defensin-1 (CRKTSFKDLWDKRF), and anti- bodies were subsequently affinity-purified using this peptide coupled to AF-Amino Toyopearl 650 M resin (Toso, Tokyo, Japan).

 Liquid bactericidal assay

 Bactericidal activity of honey was quantified in 100-µl volume liquid tests, in polypropylene microtiter plates (Costar Corn- ing, New York, NY, USA). For each experiment, a 50% (v/v)

stock solution of honey was freshly prepared in incubation buffer containing 10 mM phosphate buffer (pH 7.0) supple- mented with 0.03% (w/v) trypticase soy broth (TSB; BD Difco, Detroit, MI, USA). Bacteria from logarithmic phase cultures in TSB were washed twice with incubation buffer and suspended at a final concentration of 1 X 106 CFU/ml, based

on optical density. Plates were incubated at 37°C on a rotary

shaker at 150 rpm. At indicated time points, duplicate 10-µl

phosphate buffer (pH 7.0) with 1% low EEO agarose (Sigma)] of 45°C, and immediately poured into 10- X 10-cm culture plates. Wells of 1 mm diameter were punched into the agarose, and 2.5-µl samples were added to the wells and allowed to diffuse into the agarose for 3 h at 37°C. Subse- quently, the agarose was overlaid with 20 ml of double- strength nutrient agarose [6% TSB and 1% Bacto-agar (BD Difco), 45°C], and plates were incubated overnight at 37°C. Clear zones around the wells indicated antibacterial activity.

 Ultrafiltration of honey components

 Fifteen milliliters of 20% honey was centrifuged in a 5-kDa molecular weight cutoff Amicon Ultra-15 tube (Millipore, Bedford, MA, USA) at 4000 g for 45 min at room tempera- ture. The <5-kDa filtrate was collected, and the >5-kDa reten- tate was subsequently washed 3 times in the filter tube with 15 ml of demineralized water and concentrated to 0.4 ml.

 Bacterial overlay assay

 Native cationic proteins were separated by acid urea polyacryl- amide gel electrophoresis (AU-PAGE) (21). Gels were either stained with PAGE-Blue (Fermentas, St. Leon-Rot, Germany) or washed 3 X 8 min in 10 mM phosphate buffer (pH 7.0) for a bacterial overlay assay. After washing, the gel was incubated for 3 h on B. subtilis-inoculated nutrient-poor agarose (see

Agar Diffusion Assay). After removal of the gel, the agarose was overlaid with double-strength nutrient agarose and treated as described for the agar diffusion assay.

 Immunoblotting

 Proteins were separated by tris-tricine SDS-PAGE, as de- scribed previously (22), and transferred onto nitrocellulose membranes (Schleicher and Schuell, Keene, NH, USA). Membranes were subsequently blocked with 5% nonfat dry milk (Bio-Rad, Veenendaal, The Netherlands) plus 0.5 M NaCl and 0.5% (v/v) Tween-20 in 10 mM Tris-HCl, pH 7.5 (rinse buffer), for 1 h. Blocked membranes were incubated with affinity-purified antibee defensin-1 antibody at 1.4

µg/ml in rinse buffer for 2 h. After incubation with primary antibody, membranes were washed 2X for 15 min in rinse buffer, incubated with horseradish peroxidase-labeled goat-

anti-rabbit secondary antibody (Jackson ImmunoResearch West Grove, PA, USA) at 0.4 µg/ml in rinse buffer for 1 h, and washed again for 10 min. in rinse buffer and 5 min in PBS, respectively. The membrane was developed using a DAB liquid substrate kit (Sigma).

 Purification of antibacterial peptide from honey

 An amount of >5-kDa honey retentate equivalent to 13 ml of honey was dissolved in loading buffer (3M urea in 5% acetic acid with methyl green as tracking dye) and loaded on a preparative acid-urea PAGE, as described previously (21) with

slight modifications. A cylindrical gel (3.7 cm diameter, 6 cm height) in a model 491 Prep Cell (Bio-Rad) was prepared, prerun at reversed polarity for3h at 150V in 5% acetic acid at 4°C, and protein was electrophoresed at 40 mA with reversed polarity. Protein was eluted in 5% acetic acid at 0.5 ml/min and collected in fractions of 2 ml. Fractions were assessed for protein composition by tris-tricine SDS-PAGE and for antibacterial activity by bacterial overlay assay. Frac- tions containing purified antibacterial protein were pooled, concentrated, dialyzed against 0.01% acetic acid in a 3.5-kDa molecular weight cutoff MINI Slide-A-Lyzer tube (Pierce, Rockford, IL, USA), freeze-dried, and dissolved in deminer- alized water.

 Protein identification by V8 digestion with subsequent mass analysis

 Duplicate fractions (estimated to contain ~2 µg of protein each) were adjusted to 50 mM sodium phosphate (pH 7.9)

and 5% (v/v) acetonitrile. Approximately 0.5 µg of endopro- teinase Glu-C (Fluka) was added per fraction and incubated at 25°C overnight. The resulting peptide mixtures were purified and concentrated with the aid of C18 ziptips (Milli- pore) and eluted in 10 µl 90% (v/v) acetonitrile and 1% (v/v) formic acid. The samples were checked for the presence of nonautodigest peptides with a reflectron MALDI-TOF mass spectrometer (MALDI; Waters, Milford, MA, USA). Next,

samples were analyzed with ESI-tandem mass spectrometry (MS/MS). Data were acquired with a QT of 1 (Waters) coupled to an Ultimate nano-LC system (LC Packings Di- onex, Sunnyvale, CA, USA). One microliter of peptide mix- ture was diluted in 10 µl of 0.1% TFA. The peptides of both

samples were separated on a nanoanalytical column (75 µm

i.d. X 15 cm C18 PepMap; LC Packings Dionex) using a standard gradient of acetonitrile in 0.1% formic acid. The

flow of 300 nl/min was directly electrosprayed in the QT of 1 operating in data-dependent MS and MS/MS mode. The resulting MS/MS spectra were analyzed with Mascot software (Matrix Science, Boston, MA, USA). In both fractions, a doubly charged ion (VTCDLLSFKGQVND, mass 1537.8) with a sequence corresponding to the mature N terminus of bee defensin-1 could be identified (MOWSE scores >73).

  RESULTS

 Hydrogen peroxide is produced by the Apis mellifera (honeybee) glucose oxidase enzyme on dilution of honey. RS honey diluted to 40 to 20% accumulated high levels of H2O2 24 h after dilution, with a maximum of

5.62 0.54 mM H2O2 formed in 30% honey (Fig. 1A). The addition of catalase reduced H2O2 to negligible

   Figure 1. Contribution of H2O2, sugars, and MGO to the bactericidal activity of honey after 24 h. A) Mean se hydrogen peroxide accumulation in different concentrations of honey, without catalase (squares) or with catalase added (asterisks).

B) Bactericidal activity against indicated laboratory strains (top row) and against clinical isolates of vancomycin-resistant

E. faecium (VREF), methicillin-resistant S. aureus (MRSA), extended-spectrum [3-lactamase-producing E. coli (E. coli ESBL), and ciprofloxacin-resistant P. aeruginosa (CRPA) (bottom row). Bacteria were exposed to various concentrations of honey (squares), honey with catalase added (asterisks), or to honey-equivalent sugar solutions (circles). C) Killing of B. subtilis by honey in incubation buffer without addition (squares), with catalase (asterisk), with glyoxalase (small solid circles), or with catalase and glyoxalase I (inverted triangles), added to neutralize H2O2 and MGO, respectively, or by a honey-equivalent sugar solution

(circles). Data are mean se log-transformed bacterial concentration (CFU/ml).

levels (Fig. 1A) and markedly reduced the bactericidal activity against all bacteria tested, except B. subtilis (Fig. 1B). However, H2O2-neutralized honey exerted stron- ger bactericidal activity than equivalent sugar solutions (Fig. 1B). This indicates that H2O2 is important for the bactericidal activity of honey, but that additional factors must also be present. As B. subtilis was the most susceptible bacterium for nonperoxide bactericidal activity, we used it for identification of additional bactericidal factors.

The honey bactericidal compound MGO can be converted into S-lactoylglutathione (SLG) by glyoxalase I, and this product can be measured spectrophoto- metrically. RS honey contained 0.25 0.01 mM MGO. We aimed to apply glyoxalase I to neutralize the bactericidal activity of MGO in honey. This required that SLG, the reaction product of MGO, would be nonbactericidal. Indeed, the activity of up to 20 mM MGO was neutralized by conversion into SLG (Supple- mental Fig. 1), indicating that SLG up to high concen- trations did not kill the bacteria. Neutralization of MGO or H2O2 alone did not alter bactericidal activity of RS honey, but simultaneous neutralization of MGO and H2O2 in 10% honey reduced the killing of B. subtilis by 4-logs (Fig. 1C). At higher concentrations of honey, the bactericidal activity was not affected by neutralization of H2O2 and MGO (Fig. 1C), indicating that still more factors were involved.

As a first step to characterize the unknown bacteri- cidal factors, we size-fractionated honey by ultrafiltra- tion with a 5-kDa molecular weight cutoff membrane. Unfractionated honey produced a small zone of com- plete bacterial growth inhibition and a larger zone with partial growth inhibition in an agar diffusion assay with

B. subtilis (Fig. 2A). After ultrafiltration, the factors that caused complete and partial bacterial growth inhibition were separated and were present in the >5-kDa reten-

tate and the <5-kDa filtrate, respectively (Fig. 2A).

Ion exchange chromatography of the retentate indi-

cated a cationic nature of the antibacterial factors. Indeed, the polyanionic compound SPS abolished the antibacterial activity of the retentate (Fig. 2B). More- over, pepsin treatment also abolished this activity (Fig. 2B). Together, this implies that cationic antibacterial proteins were present.

We separated cationic proteins in the retentate using a native acid-urea PAGE gel, and allowed the separated components to diffuse from this gel into a B. subtilis- inoculated agar to identify antibacterial proteins. This yielded a single zone of bacterial growth inhibition that corresponded to a protein band in a Coomassie-stained gel run in parallel (Fig. 2C). This protein was purified from a larger amount of retentate using preparative acid-urea PAGE (Fig. 2D), and identified by peptide mass analysis as bee defensin-1.

To specifically assess the contribution of bee defen- sin-1 to the bactericidal activity of honey, an antibee defensin-1 antibody was raised (Fig. 2E). Like SPS, this antibody negated all bactericidal activity of the >5-kDa

retentate against B. subtilis (Fig. 3A). The <5-kDa

filtrate had only minor bactericidal activity (Fig. 3A), but this was not due to cationic compounds, since SPS

failed to neutralize this activity (Fig. 3A). Thus, bee defensin-1 was the only cationic bactericidal compound present in RS honey.

Next, we assessed the contribution of bee defensin-1 to the bactericidal activity of nonfractionated honey

               Figure 2. Identification of bee defensin-1 in honey. A) Honey was fractionated by ultrafiltration using a 5-kDa molecular weight cutoff filter tube; antibacterial activity of 2.5 µl of 80% honey, and equivalent amounts of the <5-kDa filtrate and >5-kDa retentate, were tested in an agar diffusion assay. B) Retentate equivalent to 7.5 µl of undiluted honey was tested for the presence of cationic and proteinaceous antibacterial components. Activity of cationic components was neutralized by

adding SPS, and protein was digested with pepsin, followed by 5-min inactivation at 100°C. As control, incubation for 5 min at 100°C without pepsin was performed. Activity in retentate (ret.)

was compared with that of 0.2 µg hen egg white lysozyme (lys.). C) To identify cationic antibacterial proteins in retentate, amounts of this fraction equivalent to 750 µl honey, and 3 µg lysozyme as a reference, were run in duplicate sets on a single native acid-urea PAGE gel. One half

of the gel was Coomassie-stained (left); other was used for a bacterial overlay assay with B. subtilis

(right). D) Silverstained tris-tricine SDS-PAGE of different amounts of lysozyme and preparative acid-urea PAGE-purified bee defensin-1, separated by an empty lane. E) Retentate separated on tris-tricine SDS-PAGE, blotted to nitrocellulose, stained with either Ponceau S (Pon. S, left) or immunostained with antibee defensin-1 (right).

  Figure 3. Roles of bee defensin-1 and pH in bactericidal activity of honey against B. subtilis. A) Contribution to bacte- ricidal activity of cationic components in general and of bee defensin-1 specifically was tested by neutralization with SPS or with antibee defensin-1 antibody (C-bd), respectively, at con- centrations of retentate equivalent to 20% honey (open bars) and 40% honey (solid bars); ctrl. indicates survival without

neutralization. B) To assess the contribution of bee defen- sin-1 to bactericidal activity of unfractionated honey, B. subtilis was incubated in various concentrations of honey in incuba- tion buffer (squares), or with catalase and glyoxalase I added either without (triangles) or with SPS (diamonds), or in a honey-equivalent sugar solution (circles). C) To assess the contribution of the low pH to the bactericidal activity of honey, B. subtilis was incubated in various concentrations of honey in incubation buffer (squares), or with catalase, glyox- alase I, and SPS added either without (triangles) or with neutralization to pH 7 (diamonds), or in a honey-equivalent sugar solution (circles). After 24 h, numbers of surviving bacteria were determined. Data are mean se log-trans- formed bacterial concentration (CFU/ml).

 against B. subtilis. As previously observed, >20% honey retained bactericidal activity when H2O2 and MGO were neutralized. Additional neutralization of bee de- fensin-1 strongly reduced the bactericidal activity of 20% honey but did not affect the activity of 30 and 40% honey (Fig. 3B). So, bee defensin-1 contributed to the bactericidal activity of honey, but still other bactericidal factors were involved.

Honey has a low pH, mainly because of the conver- sion of glucose into hydrogen peroxide and gluconic acid by glucose oxidase. This low pH might also con- tribute to the bactericidal activity of honey (23). Titra- tion of the pH of 40 –10% RS honey from 3.4 –3.5 to 7.0, combined with neutralization of H2O2, MGO and bee defensin-1, reduced the bactericidal activity of honey to a level identical to that of a honey-equivalent sugar solution (Fig. 3C). Thus, with this experiment, we

succeeded in identifying all bactericidal factors in RS honey responsible for killing of B. subtilis.

The contribution of the identified bactericidal fac- tors to activity against antibiotic-susceptible and -resis- tant strains of various species was tested with honey diluted to 20%, since this killed the entire inocula of all bacteria tested independent of sugar (Fig. 1). Simulta- neous neutralization of H2O2, MGO and bee defensin-1 negated all activity (Fig. 4), showing that these were the major factors responsible for broad spectrum bacteri- cidal activity of honey.

We studied the contribution of the honey bacteri- cidal factors in more detail by neutralizing the factors individually or combined. Neutralization of H2O2 alone strongly reduced the bactericidal activity against all bacteria tested except B. subtilis (Fig. 4). Neutralization of MGO alone strongly reduced killing of E. coli and

P. aeruginosa strains (Fig. 4). Neutralization of bee defensin-1 alone reduced killing of VREF, but not of the other bacteria tested (Fig. 4). When compared to neutralization of MGO alone, the additional neutraliza- tion of bee defensin-1 reduced killing of all bacteria tested, except E. coli ESBL (Fig. 4). In summary, H2O2, MGO, and bee defensin-1 differentially contributed to the activity of honey against specific bacteria, and their combined presence was required for the broad-spec- trum activity.

   DISCUSSION

 All bacterial species tested were susceptible to different combinations of bactericidal factors in honey, indicat- ing that these bacteria were killed via distinct mecha- nisms. This clearly demonstrates the importance of the multifactorial nature of honey for its potent, broad- spectrum bactericidal activity.

Some factors had overlapping activity. For instance, the activity of bee defensin-1 against most bacteria was only revealed after neutralization of MGO. This clearly demonstrates the importance of neutralizing known bactericidal factors in honey to reveal the presence of additional factors. Similarly, the contribution of the low pH for activity of honey against B. subtilis was only revealed when H2O2, MGO, and bee defensin-1 were simultaneously neutralized.

In other situations, bactericidal activity depended on the combined presence of different factors. Thus, the activity of honey against E. coli and P. aeruginosa was markedly reduced by neutralization of either H2O2 or MGO. Alternatively, the activity of certain bactericidal factors likely is more potent in the context of honey than as pure substances. This is most clearly illustrated by the activity of MGO. When tested in a buffer, >0.3 mM MGO was required for activity against B. subtilis (Supplemental Fig. 1). In contrast, as little as 0.05 mM MGO, the concentration in 20% RS honey, was suffi- cient to substantially contribute to the bactericidal activity. This suggests that the presence of the other bactericidal factors in honey enhanced the effect of

 Figure 4. Effect of neutralization of H2O2, MGO, and bee defensin-1 on bactericidal activity of honey. Hydrogen peroxide, MGO, and bee defensin-1 were neutralized in 20% honey by adding catalase (cat.), glyoxalase I (gly I) and SPS, respectively. Bactericidal activity was tested against indicated laboratory strains (left 4 panels) and against clinical isolates of VREF, MRSA,

E. coli ESBL, and CRPA (right 4 panels). A sugar solution equivalent to 20% honey was used as a reference. After 24 h, numbers of surviving bacteria were determined. Data are mean se log-transformed bacterial concentration (CFU/ml).

 MGO. It is not possible to quantify the contribution of the different factors to honey bactericidal activity since, as we have shown, these factors may have redundant activity, be mutually dependent, or have additive or synergistic activity depending on the bacterial species targeted.

We have demonstrated for the first time that honey contains an antimicrobial peptide, bee defensin-1, and that this peptide substantially contributes to the bacte- ricidal activity. Bee defensin-1 was previously isolated from royal jelly (24), the major food source for bee queen larvae (and then referred to as “royalisin”), and was identified in honeybee hemolymph (18). Royal jelly is produced by young worker bees and contains their hypopharyngeal and mandibular gland secretions (25, 26). Bee defensin-1 mRNA has been identified in the hypopharyngeal gland of young worker bees (18), suggesting this gland is involved in production of bee defensin-1 found in royal jelly (24). When worker bees age, they become the major producers of honey. Major differences develop in morphology and protein expres- sion of their hypopharyngeal glands (27, 28), e.g., several important carbohydrate-metabolizing enzymes, including glucose oxidase are expressed (29). The bees add the secretion from their hypopharyngeal glands to the collected nectar. The carbohydrate-metabolizing enzymes then convert sucrose to glucose and fructose, and glucose oxidase converts the glucose to hydrogen peroxide and gluconic acid. These latter compounds presumably are involved in prevention of microbial spoilage of unripe honey (11). Since we have found bee defensin-1 in honey, this suggests that after the transi- tion in hypopharyngeal gland function of the worker bees with age, the gland still produces bee defensin-1. This peptide, therefore, likely contributes to protection of both royal jelly and honey against microbial spoilage. It remains to be established whether bee defensin-1 is also present in other honeys. In Manuka honey, no evidence was found for the presence of antimicrobial peptides (30). For several other honeys, proteins were reported to contribute to the antibacterial activity (31, 32), but their identity remains unknown. Using our antibee defensin-1 antibody, we aim to assess the role of

bee defensin-1 for the antibacterial activity of other honeys.

Previous studies regarding the effect of low pH to antibacterial activity of honey have yielded conflicting results (11). In our study, the contribution of the low pH for activity against B. subtilis was only revealed on inactivation of all other bactericidal factors. So, in other studies, which did not employ an approach of neutral- ization of bactericidal factors in honey, the contribu- tion of the low pH of honey may easily have been overlooked.

Much effort has been put into identification of phenolic antibacterial components in honey (11). Sev- eral of these compounds have been isolated from honey, but as they were tested at concentrations far exceeding those in honey, no conclusions can be drawn regarding their contribution to honey bactericidal ac- tivity (11). Our data do not show a role of phenolic compounds in RS honey bactericidal activity.

Our approach of selectively neutralizing individual bactericidal factors present in a medical-grade honey allowed us to unravel the multifactorial bactericidal activity of a honey for the first time. We presently use the same approach to assess the contribution of these factors to activity of other honeys, and simultaneously to screen for novel bactericidal factors. Such honeys, or isolated components thereof, may serve as novel agents to prevent or treat infections, in particular those caused by antibiotic-resistant bacteria.                                                                            

 The authors thank Jorn Blom and Sadira Thomas for their help with purification of bee defensin-1; Henk Dekker for expert nano ESI-ms/ms experiments; and Ton Bisseling, Ben Berkhout, Mark van Passel, and Brendan McMorran for critically reviewing the manuscript.

   REFERENCES

 1.     Majno, G. (1975) Man and Wound in the Ancient World. Harvard University Press, Cambridge, MA, USA

2.     Molan, P. C. (2001) Why honey is effective as a medicine: its use in modern medicine. In Honey and Healing (Munn, P., and Jones, R., eds.) pp. 5–14, International Bee Research Associa- tion, Cardiff, UK

3.     Efem, S. E. E. (1988) Clinical observations on the wound- healing properties of honey. Brit. J. Surg. 75, 679 – 681

4.     Jones, R. (2001) Honey and healing through the ages. In Honey and Healing (Munn, P., and Jones, R., eds.) pp. 1– 4, Interna- tional Bee Research Association: Cardiff, UK

5.    Nathan, C. (2004) Antibiotics at the crossroads. Nature 431,

899 –902

6.     Cooper, R. A., Halas, E., and Molan, P. C. (2002) The efficacy of honey in inhibiting strains of Pseudomonas aeruginosa from infected burns. J. Burn Care Rehabil. 23, 366 –370

7.     Cooper, R. A., Molan, P. C., and Harding, K. G. (2002) The sensitivity to honey of gram-positive cocci of clinical significance isolated from wounds. J. Appl. Microbiol. 93, 857– 863

8.     Bonn, D. (2003) Sweet solution to superbug infections? Lancet Infect. Dis. 3, 608

9.    Dixon, B. (2003) Bacteria can’t resist honey. Lancet Infect. Dis. 3,

116

10.     Lusby, P. E., Coombes, A., and Wilkinson, J. M. (2002) Honey: a potent agent for wound healing? J. Wound Ostomy Continence Nurs. 29, 295–300

11.     Molan, P. C. (1992) The antibacterial activity of honey. 1. The nature of the antibacterial activity. Bee World 73, 5–28

12.     Adams, C. J., Boult, C. H., Deadman, B. J., Farr, J. M., Grainger,

M. N., Manley-Harris, M., and Snow, M. J. (2008) Isolation by HPLC and characterisation of the bioactive fraction of New Zealand manuka (Leptospermum scoparium) honey. Carbohydr. Res. 343, 651– 659.

13.     Mavric, E., Wittmann, S., Barth, G., and Henle, T. (2008) Identification and quantification of methylglyoxal as the domi- nant antibacterial constituent of Manuka (Leptospermum scopa- rium) honeys from New Zealand. Mol. Nutr. Food Res. 52, 483– 489

14.     Kwakman, P. H. S., Van den Akker, J. P. C., Guclu, A., Aslami, H., Binnekade, J. M., de Boer, L., Boszhard, L., Paulus, F., Middelhoek, P., Te Velde, A. A., Vandenbroucke-Grauls,

C. M. J. E., Schultz, M. J., and Zaat, S. A. J. (2008) Medical-grade honey kills antibiotic-resistant bacteria in vitro and eradicates skin colonization. Clin Infect Dis. 46, 1677–1682

15.     Lehrer, R. I., Barton, A., Daher, K. A., Harwig, S. S., Ganz, T., and Selsted, M. E. (1989) Interaction of human defensins with Escherichia coli. Mechanism of bactericidal activity. J. Clin. Invest. 84, 553–561

16.     White, J. W. Jr., and Subers, M. H. (1963) Studies on honey inhibine. 2. A chemical assay. J. Apicul. Res. 2, 93–100

17.     Racker, E. (1951) The mechanism of action of glyoxalase. J. Biol. Chem. 190, 685– 696

18.     Klaudiny, J., Albert, S., Bachanova, K., Kopernicky, J., and Simuth, J. (2005) Two structurally different defensin genes, one of them encoding a novel defensin isoform, are expressed in honeybee Apis mellifera. Insect Biochem. Mol. Biol. 35, 11–22

19.     Dankert, J., Van der Werff, J., Zaat, S. A., Joldersma, W., Klein, D., and Hess, J. (1995) Involvement of bactericidal factors from

thrombin-stimulated platelets in clearance of adherent viridans streptococci in experimental infective endocarditis. Infect. Im- mun. 63, 663– 671

20.     Lehrer, R. I., Rosenman, M., Harwig, S. S., Jackson, R., and Eisenhauer, P. (1991) Ultrasensitive assays for endogenous antimicrobial polypeptides. J. Immunol. Methods 137, 167–173

21.     Harwig, S. S., Chen, N. P., Park, A. S., and Lehrer, R. I. (1993) Purification of cysteine-rich bioactive peptides from leukocytes by continuous acid-urea-polyacrylamide gel electrophoresis. Anal. Biochem. 208, 382–386

22.     Schagger, H., and von Jagow, G. (1987) Tricine-sodium dodecyl sulfate-polyacrylamide gel electrophoresis for the separation of proteins in the range from 1 to 100 kDa. Anal. Biochem. 166, 368 –379

23.     Yatsunami, K., and Echigo, T. (1984) Antibacterial activity of honey and royal jelly. Honeybee Sci. 5, 125–130

24.     Fujiwara, S., Imai, J., Fujiwara, M., Yaeshima, T., Kawashima, T., and Kobayashi, K. (1990) A potent antibacterial protein in royal jelly. Purification and determination of the primary structure of royalisin. J. Biol. Chem. 265, 11333–11337

25.     Lensky, Y., and Rakover, Y. (1983) Separate protein body compartments of the worker honeybee (Apis mellifera L). Comp. Biochem. Physiol. B Biochem. Mol. Biol. 75, 607– 615

26.     Knecht, D., and Kaatz, H. H. (1990) Patterns of larval food- production by hypopharyngeal glands in adult worker honey- bees. Apidologie 21, 457– 468

27.     Ohashi, K., Natori, S., and Kubo, T. (1997) Change in the mode of gene expression of the hypopharyngeal gland cells with an age-dependent role change of the worker honeybee Apis mellif- era L. Eur. J. Biochem. 249, 797– 802

28.     Sasagawa, H., Sasaki, M., and Okada, I. (1989) Hormonal-control

of the division of labor in adult honeybees (Apis-Mellifera L). 1. Effect of methoprene on corpora allata and hypopharyngeal gland, and its alpha-glucosidase activity. Appl. Entomol. Zool. 24, 66 –77

29.     Ohashi, K., Natori, S., and Kubo, T. (1999) Expression of amylase and glucose oxidase in the hypopharyngeal gland with an age-dependent role change of the worker honeybee (Apis mellifera L.). Eur. J. Biochem. 265, 127–133

30.     Weston, R. J., Brocklebank, L. K., and Lu, Y. R. (2000) Identi-

fication and quantitative levels of antibacterial components of some New Zealand honeys. Food Chem. 70, 427– 435

31.     Mundo, M. A., Padilla-Zakour, O. I., and Worobo, R. W. (2004) Growth inhibition of foodborne pathogens and food spoilage organisms by select raw honeys. Int. J. Food Microbiol. 97, 1– 8

32.     Gallardo-Chacon, J. J., Casellies, M., Izquierdo-Pulido, M., and Rius, N. (2008) Inhibitory activity of monofloral and multifloral honeys against bacterial pathogens. J. Apicul. Res. 47, 131–136

33.   https://cloverhoney.web.id/

34.   https://cloverhoney.web.id/clover-honey-madu-hdi/

35.   https://cloverhoney.web.id/propoelix/

36.   https://cloverhoney.web.id/royal-jelly-hdi/

37.   https://cloverhoney.web.id/clover-honey-harga/

38.   https://cloverhoney.web.id/propoelix-harga/

39.   https://cloverhoney.web.id/hdi-propoelix-adalah/

40.   https://cloverhoney.web.id/manfaat-propoelix/

41.   https://cloverhoney.web.id/madu-hdi-harga/

42.   https://cloverhoney.web.id/propoelix-plus/

43.   https://cloverhoney.web.id/madu-hdi-manfaatnya/

44.   https://cloverhoney.web.id/clover-honey-manfaatnya/

45.      

Received for publication November 18, 2009.

Accepted for publication February 4, 2010.

[sanzymebiologics]

Benefits of Bacillus Subtilis Probiotic

Bacillus subtilis is known as a spore creating a Gram-positive bacterium found in soil and the gastrointestinal tract of ruminants, like cattle, goats, and sheep. It can also be found in the human GI tract.

Bacillus subtilis can easily survive in harsh environmental conditions. Its spores can live up to six years in space if coated by dust particles protecting it from the UV rays.

This bacterium is used widely on an industrial scale by biotechnology companies in India to produce enzymes, pharmaceutical components, and GMOs. As for human probiotics, Bacillus subtilis has always been neglected.

The cultures of bacillus subtilis were quite popular all over the world before the introduction of antibiotics. Bacillus subtilis was used as an immunostimulatory agent in order to aid the treatment of gastrointestinal and urinary tract diseases. But, after the 1950s, probiotics declined in popularity because of antibiotics.

Bacillus subtilis is extensively used in the livestock and poultry industries as an alternative to antibiotics.

Here are a few benefits of Bacillus subtilis probiotic that you must know about:

1.     B.subtilis can signal the molecules to induce the heat shock protein Hsp27 in mammalian cells which then protects the intestinal cells against oxidant-mediated tissue damage or loss of barrier function

2.     B.subtilis can significantly reduce antibiotic-associated diarrhea incidence among humans, preventing nausea, bloating, vomiting, and abdominal pain.

3.     B.subtilis and E.faecium can help reduce the severity and frequency of abdominal pain among patients who suffer from Irritable Bowel Syndrome.

4.     Addition of B.subtilis probiotic can significantly reduce the effect of ulcerative colitis.

5.     A higher dose of B.subtilis can administer ameliorated dysbiosis and gut inflammation by balancing beneficial and harmful bacteria associated with anti- and pro-inflammatory cytokines.

6.     A study found that B.subtilis probiotics can improve H. pylori eradication and decreased diarrhea when used in conjunction with triple therapy.

7.     B.subtilis can inhibit the growth of various pathogenic bacteria and decrease respiratory infections among the elderly.

8.     Metabolites of B.subtilis can help to decrease the resistance of urogenital pathogenic microflora to antibiotics in patients who have urinary tract infections resulting in accelerated elimination.

9.     According to a study, a probiotic containing both B.faecium and B.subtilis shifted the intestinal microbiota among patients who have liver cirrhosis back. These probiotics can also reduce circulating endotoxin levels in cirrhotic patients with endotoxemia.

Probiotic Bacillus subtilis is a gram-positive, catalase-positive bacterium. It can be found in soil as well as in the gastrointestinal tract of humans. This bacterium can help to activate the production of specific antibodies, interferons, and cytokines which can help white blood cells to fight infections. Species of Probiotic Bacillus subtilis have been effective in protecting from gut infections like diarrhea and controlling irritable bowel syndrome.

[feel-younger]

Natural remedy for coronavirus discovered

An international team of US and Chinese scientists have discovered that a natural enzyme called catalase can be effective against COVID-19 symptoms by suppressing the replication of SARS-CoV-2 coronavirus. This is reported in an article published in the journal Advanced Materials.

Researchers have demonstrated that the enzyme has anti-inflammatory effects and is able to regulate the production of cytokines, signaling protein molecules synthesized by leukocytes.

Cytokines are involved in the immune response and, in excess amounts seen in a cytokine storm, can provoke deadly systemic inflammation. Catalase can also protect the cells lining the inner lining of the alveoli in the lungs.

In addition, experiments have shown that catalase can suppress the replication of the SARS-CoV-2 virus in rhesus monkeys without causing toxic effects.

Earlier, on September 28, it was reported that scientists at the University of Washington created a drug from a mixture of antibodies obtained from recovered patients with COVID-19, which effectively recognizes and blocks the mechanism of infection by the pandemic coronavirus and prevents it from entering cells.

[koncptnext]

MCQ of the day- 18 september

1. A 65 yr old man c/o low grade fever at night with periods of shaking chills and coughing up blood in sputum. An acidfaststain of the sputum shows AFB. The virulence factor of the organism is encoded by _____ gene

(A) Amp C

(B) kat G

(C) vpr

(D) vpu

Answer: Option (B) is the correct answer

Reference: Harrison’s Infectious Diseases; Pg 600

Option (B): The katGgene encodes for catalase/peroxidase enzymes that protectmycobacterium against oxidative stress

Option (A): AmpC confers drug resistance in gram negative bacilli

Option (C), (D) : Non structural genes of HIV

2. A homeless man unexpectedly died in a nighttime shelter. An acidfast

stain slide of tissue from the lungs during autopsy revealed AFB.HPE of the lung tissue showed granuloma with caseous necrosis. The probable host response is

(A) Delayed hypersensitivity

(B) humoral immune response

(C) Cell mediated immune response

(D) innate immunity

Answer: Option (C) is the correct answer

Reference: Apurba Sastry Essentials of Medical Microbiology, 2nd edition 283

Option (C): The formation of soft tubercle with caseous necrosis is a favourable sign of good host cell mediated immune response. Growth of M. tuberculosis is inhibited within this necrotic environment because of low oxygen tension and low pH. Eventually, the lesion heals and calcifies

Option (A): In patients with risk factors CMI is weak; bacilli is more virulent and hence there is a delayed hypersensitivity reaction (DTH) which leads to lung tissue destruction

Option (B): humoral immune response has a minor role.

3. A 45yr old man presented to the skin OPD with leonine facies, eyebrow alopecia, symmetric multiple infiltrated nodules and ulnar nerve palsy. A skin biopsy in this patient will reveal a bacteriological index of

(A) 0-1 +

(B) 2-3+

(C) 3-5+

(D) 4-6+

Answer: Option (D) is the correct answer

Reference: Harrison’s Infectious diseases; Pg 620

Option (D): The clinical picture is suggestive of lepromatous leprosy. The Bacteriological index in LL is 4-6+

Option (A): The Bacteriological index in Tuberculoid leprosy (TT, BT) is 0-1++

Option (C): The Bacteriological index in Borderline leprosy is 3-5+

4. A 40yr old woman presents to skin OPD with 2 sharply defined annular patch in the left forearm. The skin lesion was anaesthetic. The possibility of eliciting an IgM antibody response to M.leprae  PGL-1 in this patient is

(A) 60%

(B) 75%

(C) 85%

(D) 95%

Answer: Option (A) is the correct answer

Reference: Harrison’s Infectious Diseases; Pg 620

Option (A): Theclinical picture is suggestive of tuberculoid leprosy. In tuberculoid leprosy—patients have significant antibodies to PGL-1 only 60% of the time

Option (C): IgM antibodies to PGL-1 are found in 85% of Borderline (BB, BL leprosy patients

Option (D): IgM antibodies to PGL-1 are found in 95% of untreated lepromatous leprosy patients

5. A 35yr old man was diagnosed with MDR TB and was started on DOTS plus regimen. All the following drugs are a part of the regimen except

(A) Kanamycin

(B) Clarithromycin

(C) Cycloserine

(D) Ofloxacin

Answer: Option (B) is the correct answer

Reference: : Apurba Sastry Essentials of Medical Microbiology 2ndedition pg no: 293

Option (B): DOTS plus regimen does not include clarithromycin.

Option (A), (C), (D): DOTS plus regimen include a) intensive phase – kanamycin, Ofloxacin or Levofloxacin, Ethionamide, Cycloserine, Pyrazinamide, Ehtambutol with or without Isoniazid. b)Continuation phase - Ofloxacin or Levofloxacin, Ethionamide, Cycloserine, Ehtambutol

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[themodernvedic]

Properties of Aloe Vera (Aloe Barbadensis Miller)

The earliest records of aloe vera come from Egyptian drawings depicting aloe vera on walls of temples as they had named it, "the plant of immortality". In ancient Egypt, when a Pharaoh died, a mixture of aloe vera and myrrh (gum extracted from thorny plants) was wrapped with him for embalming. The Russians called aloevera "the elixir of longivity" due to its rejuvenating powers. Aloe vera was always found in mission's yard, during Christopher Columbus' second voyage to America in 1494, as according to him, four vegetables are indispensable at all times for the well being of a man (wheat, grape, olive and aloe).

Chemical Constituents of Aloevera Vitamins: Aloe contains vitamins A (beta-carotene), C and E, which are antioxidants. It also contains vitamin B12, folic acid, and choline. Enzymes: Aloe contains 8 enzymes namely aliiase, alkaline phosphatase, amylase, bradykinase, carboxypeptidase, catalase, cellulase, lipase, and peroxidase. Minerals:  It provides calcium, chromium, copper, selenium, magnesium, manganese, potassium, sodium and zinc. Sugars:  It provides monosaccharides (glucose and fructose) and polysaccharides: (glucomannans/polymannose). Anthraquinones:  It provides 12 anthraquinones, which are phenolic compounds traditionally known as laxatives, Aloin and emodin. Fatty acids:  It provides 4 plant steroids namely cholesterol, campesterol, β-sisosterol and lupeol. Hormones:  It contains auxins and gibberellins that help in wound healing. Others:  It provides 20 of the 22 human required amino acids. Medicinal Properties The medicinal value of aloevera has been widely acclaimed for many centuries. Dioscorides, the author of Greek Herbal from first century AD, wrote an extensive report on aloevera for the treatment for conditions like insomnia, stomach disorders, burns, sun burns, facial edema or swelling, inflammation, pain, constipation and fungal infections. Aloevera posses the following medicinal properties (as discovered till now) : Healing Properties Skin Care Anti-inflammatory Boosts Immunity system Laxative Antiviral and Anti-tumor Anti-ageing Antiseptic

Each leaf of aloevera plant is composed of three layers: An inner clear gel that contains 99% water and the rest is made up of glucomannans, amino acids, lipids, sterols and vitamins. The middle layer of latex which is the bitter yellow sap, and contains anthraquinones and glycosides. The outer thick layer of 15–20 cells also known as rind which has protective function along with synthesizing carbohydrates and proteins. Healing Properties The glucomannan ( mannose-rich polysaccharide) and gibberellin (growth hormone) in aloe vera

interacts with growth factor receptors on the fibroblast, thereby stimulating its activity and proliferation, which in turn significantly increases the collagen synthesis in your body after topical and oral consumption of aloe vera. Aloe gel not only increases collagen content of the wound but also changes the collagen composition (more type III) and increases the degree of collagen cross linking. Aloe vera accelerates wound contraction and increases the breaking strength of the resulting scar tissue. Cures Skin Conditions Aloevera gel has a protective effect against radiation damage to the skin. Its Exact role is not known,but due to aloevera gel, metallothionein (an antioxidant protein) gets generated in the skin, which scavenges the hydroxyl radicals and prevents suppression of superoxide dismutase and glutathione peroxidase in the skin. It reduces the production and release of skin keratinocyte  derived immuno-suppressive cytokines such as interleukin-10 (IL-10) and thus prevents UV-induced suppression of delayed type hypersensitivity. Anti-inflammatory Activity Aloevera can inhibit the cyclooxygenase pathway and reduce the production of prostaglandin E2 from arachidonic acid. The most recent anti-inflammatory compound called C-glucosyl chromone has been isolated from aloe gel extracts. Boosts Immunity Alprogen inhibits calcium influx into mast cells, thereby inhibiting

the antigen-antibody-mediated release of histamine and leukotriene from mast cells. Several low-molecular-weight compounds of aloe vera are also capable of inhibiting the release of reactive oxygen free radicals from activated human neutrophils. Aloe Vera when consumed orally keeps you strong and safe against most diseases and infections. Laxative Anthraquinones present in the latex of aloevera leaf are a potent laxative. It increases intestinal water content, stimulates mucus secretion and increases intestinal peristalsis in our body. Antiviral and Anti-tumor The antiviral and antitumor actions of aloevera may be due to indirect or direct effects. Indirect effect is due to stimulation of the immune system due to aloe vera and the direct effect is due to anthraquinones. The anthraquinone aloin inactivates various enveloped viruses such as herpes simplex, varicella zoster and influenza. The polysaccharide fraction inhibits the binding of benzopyrene to primary hepatocytes, thereby preventing the formation of potentially cancer-initiating benzopyrene-DNA adducts. An induction of glutathione S-transferase and an inhibition of the tumor-promoting effects of phorbol myristic acetate has also been reported, which suggests a possible benefit of using aloe gel in cancer chemo-prevention as well. Anti-ageing Properties

The mucopolysaccharides of aloe vera help in binding moisture to the aloevera leaves, stimulating fibroblast which produces the collagen and elastin fibers making the skin more elastic and less wrinkled. It also has cohesive effects on the superficial flaking epidermal cells by sticking them together, which softens the skin. The amino acids also soften hardened skin cells. Zinc acts as an astringent to tighten pores. Its moisturizing effects have also been studied in treatment of dry skin associated with occupational exposure. Aloe vera gel improved the skin integrity, along with decreasing the fine wrinkles and erythema. Aloe Vera has an anti-acne effect as well. Antiseptic Properties Aloevera contains 6 antiseptic agents: Lupeol, salicylic acid, urea nitrogen, cinnamonic acid, phenols and sulfur. They all have inhibitory action on fungi, bacteria and viruses. Oral consumption of aloevera is not recommended during pregnancy due to theoretical stimulation of uterine contractions, and in breastfeeding mothers, it may sometime causes gastrointestinal distress in the nursing infant. Read the full article

[bostorbio]

Catalase Antibody — Boster Bio

It encodes the antioxidant enzyme catalase (Catalase Antibody), which is essential for the body's defence against oxidative stress. This gene. There are several enzymes in the peroxisomes of aerobic cells that break down heme, including catalase. Hydroxyl radicals, such as hydrogen peroxide, are deactivated by catalase, an enzyme in the body that converts them to water and oxygen. Oxidative stress has been linked to the development of several long-term and debilitating disorders including diabetes, Alzheimer's disease, rheumatoid arthritis, systemic lupus, and cancer. As of yet, only acatalasemia has been shown to be associated to this gene.

Biochemical and Physiological reactions

Reactive oxygen species are removed from the body with the help of catalase (Catalase Antibody). Deficiency of the catalase (CAT) gene causes the development of essential hypertension (EH). Hydrogen peroxide is broken down into water and molecular oxygen by it.

Descriptions and Benefits

You'll be able to examine your antibodies with complete confidence. As a customer, you may anticipate a complete refund or a replacement antibody if the antibody doesn't perform as intended in your application.

Phenomenological kind Sodium azide, 0.02 percent, and 50% glycerol in PBS (pH 7.4) with rabbit IgG. pH 7.4 (in the absence of Mg2+ and Ca2+).

[feiyuebio-lottieshi]

Bovine Catalase (CAT) ELISA Kit

Bovine CAT(Catalase) ELISA Kit Basic Information

Feiyue's Bovine CAT(Catalase) ELISA Kit is an ELISA reagent for detection of CAT(Catalase), plasma or cell with sensitivity, specificity and consistency.

CAT(Catalase) Introduction

Catalase is a common enzyme found in nearly all living organisms exposed to oxygen (such as bacteria, plants, and animals) which catalyzes the decomposition of hydrogen peroxide to water and oxygen. It is a very important enzyme in protecting the cell from oxidative damage by reactive oxygen species (ROS). Likewise, catalase has one of the highest turnover numbers of all enzymes; one catalase molecule can convert millions of hydrogen peroxide molecules to water and oxygen each second.

Bovine CAT(Catalase) ELISA Kit Test method

This ELISA kit uses the Sandwich-ELISA principle. The micro plate provided in this kit has been pre-coated with an antibody specific to Bovine CAT. Standards or samples and Horseradish Peroxidase (HRP) labeled detection antibody specific for Bovine CAT are added to the plate wells together and incubated. After washing off unbound material, TMB substrate solution is added to all wells and incubated. An enzyme-catalyzed reaction generates a blue color in the solution, thereafter, stop solution is added to stop the substrate reaction and the color turns yellow. The yellow solution is read at a wavelength of 450nm. The concentration of Bovine CAT in the samples is then calculated from the OD value by establishing a standard curve.

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lottie@feiyuebio.com

[abbkineus]

New Post has been published on Abbkine - Antibodies, proteins, biochemicals, assay kits for life science research

New Post has been published on https://www.abbkine.com/chekine-catalase-cat-activity-assay-kit/

Want High accuracy and specificity? Yes, it’s Abbkine CheKine™ Catalase (CAT) Activity Assay Kit with great value

【Background】

Catalase is a common enzyme found in nearly all living organisms exposed to oxygen (such as bacteria, plants, and animals). It catalyzes the decomposition of hydrogen peroxide to water and oxygen. It is a very important enzyme in protecting the cell from oxidative damage by reactive oxygen species (ROS). Likewise, catalase has one of the highest turnover numbers of all enzymes; one catalase molecule can convert millions of hydrogen peroxide molecules to water and oxygen each second.

Catalase is a common enzyme found in nearly all living organisms exposed to oxygen (such as bacteria, plants, and animals). It catalyzes the decomposition of hydrogen peroxide to water and oxygen. It is a very important enzyme in protecting the cell from oxidative damage by reactive oxygen species (ROS). Likewise, catalase has one of the highest turnover numbers of all enzymes; one catalase molecule can convert millions of hydrogen peroxide molecules to water and oxygen each second.

Catalase is a tetramer of four polypeptide chains, each over 500 amino acids long. It contains four iron-containing heme groups that allow the enzyme to react with the hydrogen peroxide. The optimum pH for human catalase is approximately and has a fairly broad maximum, the rate of reaction does not change appreciably between pH 6.8 and 7.5. The pH optimum for other catalases varies between 4 and 11 depending on the species. The optimum temperature also varies by species.

【Abbkine Catalase Activity Assay Kit】

Abbkine Catalase Activity Assay Kit utilizes the peroxidatic function of catalase for measuring

catalase activity, based on the reaction of catalase with methanol, with the presence of an optimal concentration of H2O2. The formaldehyde produced can be measured colorimetrically at OD 540 nm. Therefore, the catalase activity present in the sample is proportional to the signal obtained.

Most commercial Catalase Activity Assay Kits apply this principle that residual hydrogen peroxide is oxidized by peroxidase to form the colored substrate, and the catalase activity was detected indirectly. However, other peroxidases in the sample may interfere with the experimental results and this method may cause standard curve errors due to unstable hydrogen peroxide.

Abbkine kit has unique advantages, which can detect the enzyme activity directly, with better more veracity and higher specificity. Since methanol is a unique substrate of catalase, other peroxidases cannot use methanol as a substrate, so interference signals are avoided.

Product name Cat# Detection Range CheKine™ Catalase (CAT) Activity Assay Kit KTB1040 2-75 µM

【Kit components】

• Assay Buffer (10x)

• Sample Diluent (10x)

• Formaldehyde standard (4.25 M)

• Catalase (positive control)

• Potassium Hydroxide

• Hydrogen Peroxide

• Chromogen

• Potassium Periodate

【Features & Benefits】

Determination of catalase activity in serum, plasma, tissue/cell lysates and other biological fluids.

A broad range linearity of 2-75 µM, measure catalase activity down to 2 U/ml

Determining catalase activity directly by utilizing the peroxidase function of catalase, which cannot be interfered by other peroxidases. 

Simple operation, only four steps to complete the measurement

【Results Analysis】

Formaldehyde (µM)

Calculate the formaldehyde concentration of the samples using the equation obtained from standard

2）Calculate the CAT activity of the sample using the following equation. One unit is defined as the amount of enzyme that will cause the formation of 1.0 nmol of formaldehyde per minute at 25°C

Note: µM means nmol/ml

Please refer to Product datasheet: https://www.abbkine.com/file/booklet/KTB1040-B.pdf

About Abbkine Scientific Co., Ltd.

Abbkine serves global scientists in the field of proteomics and cytology and is committed to the innovation and development of various scientific reagents related to proteomics and cytology, expecting to accelerate the pace of life science research and drug discovery. Proteomics products cover the preparation of samples (protein extraction, purification, coupling), protein quantification, antibodies and kits for protein detection. Cytology products involve cytokines (cell culture), cell status detection, cell staining, organelle extraction, cell metabolism and cytopathology reagents (kits). Abbkine relies on the product portfolio and unique marketing support as the main market strategy and product innovation mode, with ultimate aim to facilitate your research career.

[petshopplus]

CELL ADVANCE™ 880 . SUMMARY: Cell Advance™ 880 for dogs supports immune system health and is designed to work in concert with traditional or alternative therapies. Cell Advance™ 880 is recommended for dogs over 30lbs . . FULL DETAILS: Cell Advance™ 880 by VetriScience® Laboratories is an advanced formula that includes 23 powerful antioxidants otherwise known as free radical scavengers. Vitamins A, C, E and B6 support the immune system and protect against unwanted free radical damage. Vitamin B6 is provided in two forms: one in an active form for amino acid metabolism and one in a form appropriate for animals with reduced B6 levels. Coenzyme Q10 is a necessary co-factor for ATP production and immune system support. Enteric coated amino acids l-cysteine, l-lysine, methionine and l-glutathione support antibody production, cellular respiration and antioxidant activity. Enteric coating allows each ingredient to be utilized where it is needed most.  Cell Advance™ 880 also includes minerals. Magnesium, manganese, copper and zinc support normal detoxification and enzyme production and utilization. The inclusion of the enzyme catalase supports cellular respiration and deactivates hydrogen peroxide. SOD, or Super Oxide Dismutase, is an enzyme that rids the body of free radicals.  Cell Advance™ includes bioflavonoids like quercetin, rutin and hesperidin to support vascular and connective tissue health while maintaining healthy collagen levels. Our easy to administer capsules support the immune system at the cellular level and protects the cell structure from free radical damage. . . #PetShopPlus #dogs . . https://www.instagram.com/p/ByTIksnBIHO/?igshid=1v243rebr4sdx

[sanzymebiologics]

Does Garlic Kill Good Gut Bacteria?

We all love garlic as an antimicrobial for the gut. It covers many possible pathogens which includes Escherichia, Salmonella, Staphylococcus, Klebsiella, Proteus, Bacillus, Clostridium, Neisseria, Proteus, Pseudomonas, Shigella, Mycobacterium, and Helicobacter Pylori – all of them where the potential poster bacteria for life-threatening diseases.

The antimicrobial properties of garlic doesn’t end here, as it has also proven to be a very effective antifungal, antiprotozoal (like Giardia and Cryptosporidium which are dangerous infections prevented and stopped by garlic), and antiviral properties. It can also kill viruses upon direct contact, including those responsible for viral meningitis, viral pneumonia, as well as herpes infections. There is also many substantial evidence which supports the claim of pathogens. However, what is the effect of garlic on the good gut bacteria such as Lactobacillus and Bifidobacterium? Does it kill them?

Well, the answer is NO. Let’s check out the facts.

Garlic has antibacterial properties.

This antibacterial property is basically concentration or dose-dependent. There have to be certain concentrations available to produce an effective antibacterial action that is true for any antibacterial compounds; even for antibiotics, you’ve to take certain concentrations to produce this effect. A lower amount of concentration will not produce antibacterial action.

We can also consume garlic through some foods, and the amount gives a mild garlic aroma. Do not take the bowlful of garlic and munch on them.

The garlic, which we consume, is generally through specific food items when mixed with other non-garlic foods in the diet. In the stomach and in the digestive tract, the little amount of garlic we consume gets diluted in the intestine. So in the intestinal bacteria that little amount of garlic gets highly diluted.

Probiotic bacillus subtilis is known as a gram-positive and catalase-positive bacteria. It can be found in soil and even in the gastrointestinal tract of humans. This bacterium can help activate some specific antibodies like interferons and cytokines that can help white blood cells fight infections. Some species of Probiotic bacillus subtilis have also been effective in protecting gut infections like diarrhea and controlling irritable bowel syndrome.

Bacillus subtilis SNZ 1972 is originally named Vibrio subtilis by Christian Gottfried Ehrenberg which was later renamed as Bacillus subtilis by Ferdinand Cohn in 1872. This bacterium is also known by many names like hay bacillus, grass bacillus, or Bacillus globigii. It is also widely used for safe, well documented, and stable spore-forming bacteria that promotes gastrointestinal health.

[bioadvisers]

Bioadvisers shared on Biotech Advisers

Metabolic column Catalase (Catalase) activity detection kit magical efficacy

What is catalase (CAT)? As the name implies, it is an enzyme that catalyzes the decomposition of hydrogen peroxide into oxygen and water. It is present in the body’s peroxide. Catalase is a marker enzyme for peroxisomes, accounting for about 40% of the total peroxisomal enzymes. Catalase is present in all tissues of all known animals, especially at high concentrations in the liver. Catalase is used in the food industry to remove hydrogen peroxide from milk used to make cheese. Catalase is also used in food packaging to prevent food from being oxidized.

Catalase exists in red blood cells and peroxides in some tissues. Its main function is to catalyze the decomposition of H2O2 into H2O and O2, so that H2O2 will not react with O2 under the action of iron chelate to form very harmful- OH. This is one of the reasons why catalase (CAT) has become a key biochemical indicator for researchers.

The role of catalase is to reduce hydrogen peroxide to water: 2H2O2 = O2↑ + 2H2O.

Catalase has multiple functions. People have named them according to their different functions:

Catalase

Catalase (CAT) is an enzyme scavenger, also known as catalase, a binding enzyme that uses iron porphyrin as a prosthetic group. It can promote the decomposition of H2O2 into molecular oxygen and water, remove hydrogen peroxide in the body, and thus protect the cells from H2O2. It is one of the key enzymes in the biological defense system. The mechanism of CAT acting on hydrogen peroxide is essentially the disproportionation of H2O2. Two H2O2 must meet CAT successively and collide with the active center before the reaction can take place. The higher the H2O2 concentration, the faster the decomposition rate.

Decomposing enzymes

This is a stable hydrogen peroxide decomposing enzyme, which can decompose hydrogen peroxide into water and oxygen without affecting fibers and dyes. Therefore, after dyeing after bleaching, H2O2 decomposing enzymes are used to remove the residues on the bleached fabric and the dyeing tank. Hydrogen peroxide to avoid further oxidation of the fibers and oxidation of dyes during dyeing. At the same time, it can shorten the processing time, reduce the water used for washing and reduce the amount of waste water. Especially suitable for yarn, package yarn and knitted fabric. Similarly, with the change of pH value and temperature, the activity of hydrogen peroxide decomposing enzyme changes accordingly, and the activity is greatest around pH7 and 30~40℃. Increasing the concentration of hydrogen peroxide will speed up the decomposition reaction, but it must be noted that when the concentration is greater than a certain amount, the role of the enzyme will be weakened, so that excessive residual H2O2 is detrimental to fibers and dyes. Therefore, the amount of H2O2 cannot be increased arbitrarily because of the H2O2 decomposing enzyme. When using, usually pay attention to the compatibility of H2O2 decomposing enzyme to common surfactants and H2O2 stabilizers. The actual production and application pH is 6~8, temperature is 20~55℃, enzyme dosage is 5 ~ 10 KCLU/liter, time is 10~20 min . This technology has been slowly recognized and accepted in China, and it is very beneficial to improve the vividness of reactive dyes.

In order to carry out qualitative and quantitative research on this indicator, Abbkine has designed a set of kits for professional detection of catalase (CAT) level: KTB1040 CheKine ™ Catalase (CAT) Activity Assay Kit。

Cat NO Product Name Biomarker Function KTB1040 CheKine™ Catalase (CAT) Activity Assay Kit Catalase (CAT) Quantitative

The kit has the following characteristics:

Determination of catalase activity in serum, plasma, tissue/cell lysates and other biological fluids.

Catalase activity is directly measured using the catalase’s peroxidation function, and catalase is not interfered by other peroxidases.

Extensive detection range: 2-75 µM.

Measure catalase activity as low as 2 U/ml.

The linearity of the standard product is good, and the coefficient R2 can generally reach more than 0.998.

The research field of this kit is very extensive. In terms of plant research, it mainly includes anti-stress response, photorespiration, mitochondrial electron transport, cold resistance and fatty acid β-oxidation, etc., revealing the microscopic world of plant research and a series of enzyme-catalyzed biochemical reactions. In terms of animal body research, it mainly includes the mechanism of action of gastric digestive enzymes, the intestinal mucosal oxygenated active substance (ROS), the effect of nanoparticles on cell oxidation, and the process of human cell metabolism. In terms of microbial research, it mainly includes strain screening, identification and fermentation to produce catalase, etc., revealing the wonderful world of microbial research and industrial production. In addition, the kit has many applications in food engineering, metabolic engineering, cancer research, etc.

  Abbkine specializes in the fields of proteinology and cytology, and is committed to innovating and developing various antibodies, proteins, analytical reagents and kits, with a view to becoming a key promoter in the fields of life science research and development, drug research and development. We provide you with the favorite products of protein and immunological research users, from basic immunological products, such as protein extraction and quantification, to the internal reference labeling antibodies, primary antibodies and secondary antibodies of immunological experiments, etc.; the favorite products of cell research users, from Dyes and kits for detecting the state of cells, kits for extracting organelles, staining and tracking of cell substructures and cell metabolism detection products, and cytokine and protein detection kits for cell culture, only to help your research career! About Abbkine Our position: Serve global users of cell and protein research, and provide users with economical and technical product solutions through application processes and product portfolios. Our mission: to stimulate our inner creativity, provide competitive biomedical products and services, and continue to create maximum value for customers. Our vision: to be a respected, world-class supplier of biomedical products and services.