Lactoperoxidase Antibacterial System: Natural Occurrence, Biological Functions and Practical Applications

1984 ◽  
Vol 47 (9) ◽  
pp. 724-732 ◽  
Author(s):  
BRUNO REITER ◽  
GÖRAN HÄRNULV
Keyword(s):  
Hydrogen Peroxide ◽  
Cytoplasmic Membrane ◽  
Natural Occurrence ◽  
Biological Functions ◽  
Animal Cells ◽  
Milk Products ◽  
Practical Applications ◽  
In Vitro Effects

In the present review dealing with the antibacterial lactoperoxidase (LP) system, it is shown that the two reactants thiocyanate (SCN−) and hydrogen peroxide (H2O2) as well as the catalytic enzyme lactoperoxidase (LP) are widely distributed in nature and that evidence for the activity of the LP system in animals, including man, is accumulating. The in vitro effects on bacterial and animal cells are discussed and the unique action of the LP system on the bacterial cytoplasmic membrane is pointed out. Some practical applications are also presented, with particular emphses on the possibility of utilizing the LP system to preserve the quality of raw, cooled as well as uncooled milk. It is concluded that the addition of minute quantities of SCN− and H2O2 (ca. 12 and 8 ppm, respectively) to secure an optimum activity of the LP system should be harmless to the consumer of milk and milk products treated in this way.

scholarly journals Genetic or pharmacological superoxide-hydrogen peroxide imbalances modulate the in vitro effects of lithium on glycogen synthase kinase-3β

Gene ◽  
2018 ◽  
Vol 655 ◽  
pp. 48-55 ◽  
Author(s):  
Fernanda Barbisan ◽  
Verônica Farina Azzolin ◽  
Gustavo Cardenas Monteiro ◽  
Cibele F. Teixeira ◽  
Moisés Henrique Mastella ◽  
...  
Keyword(s):  
Hydrogen Peroxide ◽  
Glycogen Synthase ◽  
Glycogen Synthase Kinase ◽  
Glycogen Synthase Kinase 3Β ◽  
In Vitro Effects

The protective effect of melatonin on the in vitro development of yak embryos against hydrogen peroxide-induced oxidative injury

Zygote ◽  
2019 ◽  
Vol 27 (3) ◽  
pp. 118-125 ◽  
Author(s):  
Wei Peng ◽  
Mengtong Lei ◽  
Jun Zhang ◽  
Yong Zhang
Keyword(s):  
Oxidative Stress ◽  
Hydrogen Peroxide ◽  
Critical Role ◽  
Underlying Mechanism ◽  
Preimplantation Embryos ◽  
Effective Antioxidant ◽  
Vitro Development ◽  
Oxidation Effect

SummaryMelatonin plays a critical role in several types of cells as an antioxidant to protect intracellular molecules from oxidative stress. The anti-oxidation effect of melatonin in yak embryos is largely unknown. We report that melatonin can protect the development of yak preimplantation embryos against oxidative stress induced by hydrogen peroxide (H2O2). Therefore, the quality of blastocysts developed from zygotes exposed to H2O2 was promoted. In addition, we observed that melatonin reduced H2O2-induced intracellular reactive oxygen species (ROS) levels and prevented mitochondrial dysfunction in zygotes. These phenomena revealed the effective antioxidant activity of melatonin to prevent oxidative stress in yak embryos. To determine the underlying mechanism, we further demonstrated that melatonin protected preimplantation embryos from oxidative damage by preserving antioxidative enzymes. Collectively, these results confirmed the anti-oxidation effect of melatonin in yak embryos that significantly improved the quantity and quality of blastocysts in the in vitro production of embryos in yaks.

effect of treating wheat straw with sodium hydroxide and calcium oxide alone or in combination with hydrogen peroxide on the in Vitro dry matter digestibility

1990 ◽  
Vol 1990 ◽  
pp. 119-119
Author(s):  
A. S. Chaudhry ◽  
E. L. Miller
Keyword(s):  
Hydrogen Peroxide ◽  
Wheat Straw ◽  
Nutritional Quality ◽  
Dry Matter ◽  
Poor Quality ◽  
Alkaline Hydrogen Peroxide ◽  
Dry Matter Digestibility ◽  
Farm Scale

That alkali treatments can improve the nutritional quality of poor quality roughages has long been established (Sundstol and Owen, 1984). However, their effectiveness is limited by their potential hazards to the animals and mankind. Alkaline hydrogen peroxide (AHP) has recently emerged as a possible substitute (Gould, 1985) but its farm scale application is limited by the need for high amounts of chemicals and water. Lack of any information regarding its effectiveness over NaOH alone is another factor which requires further investigation. The present study was, therefore, planned to assess the effectiveness of pH-regulated (11.5±0.2) H2O2 (AHP) in improving the in vitro dry matter digestibility (IVDMD) of wheat straw (WS, Avalon) under different laboratory conditions. The possibility of using CaO on its own or to regulate pH for AHP was also tested.

scholarly journals In vitro Effects of Vitamin E on Hydrogen Peroxide

1973 ◽  
Vol 111 (1) ◽  
pp. 99-100
Author(s):  
OTOTAKA HIGASHI ◽  
YOKO KIKUCHI
Keyword(s):  
Hydrogen Peroxide ◽  
Vitamin E ◽  
In Vitro Effects

scholarly journals In vitro effects of hydrogen peroxide on rat uterine contraction before and during pregnancy

2018 ◽  
Vol 59 (6) ◽  
pp. 327-334
Author(s):  
Rahmah Alanazi ◽  
Mohammed Alotaibi ◽  
Laiche Djouhri
Keyword(s):  
Hydrogen Peroxide ◽  
Uterine Contraction ◽  
In Vitro Effects

scholarly journals In vitro effects of combined iron chelation, antibiotics and matrix disruption on clinical isolates of Pseudomonas aeruginosa

2019 ◽  
Vol 75 (3) ◽  
pp. 586-592
Author(s):  
Arun Nair ◽  
Audrey Perry ◽  
John D Perry ◽  
F Kate Gould ◽  
Julie Samuel
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Biofilm Formation ◽  
Iron Chelation ◽  
Proof Of Concept ◽  
Crystal Violet Assay ◽  
Clear Advantage ◽  
Biofilm Disruption ◽  
In Vitro Effects

Abstract Objectives Pseudomonas aeruginosa is an important pathogen in chronic suppurative respiratory diseases, with adverse effects on severity, healthcare utilization and quality of life. Aerosolized combined biofilm disruption and iron chelators offer novel proof-of-concept for improving airway antimicrobial efficacy. Our aim was to assess the activity of desferrioxamine, Dornase alfa (DNase) and antibiotics on biofilm formation and against mature preformed biofilms of P. aeruginosa. Methods Fifty-six isolates of P. aeruginosa were screened for biofilm production and seven isolates with varying capacity to form biofilms were referred for further study. Three antibiotics (colistin, tobramycin and ciprofloxacin) as well as desferrioxamine and DNase were assessed for their ability to prevent biofilm formation using the crystal violet assay. The same method was used to assess their impact on mature biofilms. Each agent, as well as combinations of these agents, was also assessed for its effect on the metabolic activity and viability of preformed P. aeruginosa biofilm by the resazurin reduction assay and by performing viable counts. Results Antibiotics alone prevented the development of biofilms and partly reduced the viability of mature biofilms. Desferrioxamine and DNase did not reduce biofilm formation. For most isolates, desferrioxamine and DNase did not offer any clear advantage over the use of antibiotics alone with respect to reducing the viability of Pseudomonas biofilms. Conclusions Colistin, tobramycin and ciprofloxacin prevented biofilm formation by P. aeruginosa and reduced the viability of mature biofilms. For most isolates, there was no clear advantage of combining these antimicrobials with desferrioxamine or DNase.

scholarly journals In Situ and In Vitro Effects of Two Bleaching Treatments on Human Enamel Hardness

2016 ◽  
Vol 27 (1) ◽  
pp. 56-59 ◽  
Author(s):  
Sandrina Henn-Donassollo ◽  
Cristiane Fabris ◽  
Morgana Gagiolla ◽  
Ícaro Kerber ◽  
Vinícius Caetano ◽  
...  
Keyword(s):  
Hydrogen Peroxide ◽  
Oral Appliance ◽  
Water Cooling ◽  
Surface Microhardness ◽  
Tukey Test ◽  
Human Enamel ◽  
Before And After ◽  
In Vitro Effects

Abstract The aim of this study was to evaluate in vitro and in situ the effects of two bleaching treatments on human enamel surface microhardness. Sixty enamel slabs from recently extracted thirty molars were used. The specimens were polished with sandpapers under water-cooling. The enamel samples were randomly divided in four groups, treated with 10% hydrogen peroxide (HP) or Whitening Strips (WS) containing 10% hydrogen peroxide and using two conditions: in vitro or in situ model. For in situ condition, six volunteers wore an intra-oral appliance containing enamel slabs, while for in vitro condition the specimens were kept in deionized water after the bleaching protocols. The bleaching treatments were applied one-hour daily for 14 days. Similar amounts of bleaching agents were used in both conditions. Before and after bleaching treatments, microhardness was measured. Statistical analysis (ANOVA and Tukey test) showed that in the in situ condition there was no statistically significant microhardness reduction in the bleached enamel (p>0.05). Significant decrease in hardness was observed for enamel slabs bleached with both treatments in the in vitro condition (p<0.05). Regarding the bleaching agents, in situ results showed no difference between HP and WS, while in vitro WS produced the lowest hardness value. It could be concluded that there was no deleterious effect on enamel produced by any of the bleaching protocols used in the in situ model. The reduction of hardness was only observed in vitro.

In Vitro Effects of Certain Membrane-acting Agents on Superoxide and Hydrogen Peroxide Production, Protein Synthesis and Membrane ATPase Activity in Buffalo PMN Cells

2007 ◽  
Vol 35 (4) ◽  
pp. 397-404 ◽  
Author(s):  
Hemen Das ◽  
Golla Ramalinga Reddy ◽  
Tukaram More ◽  
Vineet Kumar Singh
Keyword(s):  
Hydrogen Peroxide ◽  
Protein Synthesis ◽  
Atpase Activity ◽  
Antimicrobial Proteins ◽  
Level Of Activity ◽  
Membrane Atpases ◽  
In Vitro Effects ◽  
Reactive Oxidants ◽  
Proteins And Peptides

Polymorphonuclear (PMN) cells play a key role in innate immunity, due to their ability to produce reactive oxidants such as superoxide (O2–) and hydrogen peroxide (H2O2), and to release antimicrobial proteins and peptides stored in their lysosomal granules. In the present study, the effects of the activation of buffalo PMN cells with various membrane-acting agents were evaluated in terms of O2– and H2O2 production, the activities of membrane ATPases, and protein synthesis. Studies involving the incorporation of 35S-methionine revealed significant protein-synthesising ability in resting PMN cells and in cells treated with lipopolysaccharide (LPS), as well as with opsonised zymosan (OZ). Protein synthesis, as judged by fluorography of the cytosolic fraction, showed more than 12 bands, whilst the cytoskeletal fraction showed 2–3 bands. PMN activation with concanavalin A (ConA), digitonin and sodium nitroprusside (SNP) resulted in increased O2– and H2O2 production. However, in the presence of anti-inflammatory agents such as indomethacin and cortisol, the production of O2– and H2O2 by these cells was found to decline. Studies pertaining to membrane ATPases revealed that verapamil hydrochloride (VpHCl) significantly increased total ATPase and Na+K+ATPase activity. ConA treatment yielded only a moderate level of activity. Similarly, digitonin up to 24μM also caused a significant increase in ATPase activity. Our observations indicate that these membrane-acting agents influenced oxygen-dependent and oxygen-independent microbicidal mechanisms in buffalo PMN cells.

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