Detoxification of Citrinin and Ochratoxin A by Hydrogen Peroxide

1994 ◽  
Vol 77 (3) ◽  
pp. 631-637 ◽  
Author(s):  
Sophie G Fouler ◽  
Alka B Trivedi ◽  
Naofumi Kitabatake

Abstract The effects of hydrogen peroxide on citrinin and ochratoxin A toxicity were examined using HeLa cells. The citrinin was completely detoxified by prior incubation with 0.05% hydrogen peroxide for 30 min at room temperature, and the toxic compound(s) that resulted from heating citrinin at 100°C were also detoxified upon reheating it with hydrogen peroxide. On the other hand, ochratoxin A was not detoxified by hydrogen peroxide at room temperature, but its toxicity was reduced by heating ochratoxin A with hydrogen peroxide under alkaline conditions.

2013 ◽  
Vol 9 ◽  
pp. 8-14 ◽  
Author(s):  
Yan Sun ◽  
Jing Sun ◽  
Chao-Guo Yan

A fast and convenient protocol for the synthesis of novel spiro[dihydropyridine-oxindole] derivatives in satisfactory yields was developed by the three-component reactions of arylamine, isatin and cyclopentane-1,3-dione in acetic acid at room temperature. On the other hand the condensation of isatin with two equivalents of cyclopentane-1,3-dione gave 3,3-bis(2-hydroxy-5-oxo-cyclopent-1-enyl)oxindole in high yields. The reaction mechanism and substrate scope of this novel reaction is briefly discussed.


Author(s):  
Shweta Singh ◽  
Sureshbabu Popuri ◽  
Qazi Mohammad Junaid ◽  
Sabiah Shahul Hameed ◽  
Jeyakumar Kandasamy

A wide range of N-tosyl α–ketoamides underwent transamidation with various alkyl amines in the absence of catalyst, base, or additives. On the other hand, transamidation in N-Boc α–ketoamides is achieved...


Author(s):  
Ashok Kumar Jena ◽  
Jitendra Sharan

Abstract Filtering facepiece respirators (FFRs) are made for one-time use. A massive shortage of FFRs is widespread during pandemic events and has forced many healthcare organizations to decontaminate them and re-use for a limited time. Many decontamination methods have been proposed for the decontamination of FFRs. This review highlights various aspects of decontamination methods available in the literature. Among various methods available, vaporized hydrogen peroxide, ultraviolet irradiation, and dry heat seem to be the most promising decontaminants for FFRs. On the other hand, microwave, bleach, ethylene oxide, alcohol, hydrogen peroxide liquid, sanitizing wipes, and soap and water are not recommended methods for FFR decontamination.


Agronomy ◽  
2020 ◽  
Vol 10 (4) ◽  
pp. 599 ◽  
Author(s):  
Nik Nurnaeimah ◽  
Nashriyah Mat ◽  
Khamsah Suryati Mohd ◽  
Noor Afiza Badaluddin ◽  
Nornasuha Yusoff ◽  
...  

Hydrogen peroxide (H2O2) is defined as a reactive oxygen species (ROS), able to cause damage to a variety of cellular structures. On the other hand, recent work has demonstrated that H2O2 can also act as a potent signaling molecule that mediates various physiological and biochemical processes in plants. This study was carried out to investigate the effects of H2O2 on the growth, mineral nutrient accumulation, as well as the biologic and chemical properties of Ficus deltoidea var. deltoidea. F. deltoidea plants were spray-treated with 0- (control), 8-, 16-, 30- and 60-mM H2O2 under field conditions. Plant height, leaf area, chlorophyll content, net photosynthetic rate, stomatal conductance and quantum yield of the F. deltoidea plants significantly increased after treatment with 16 and 30-mM H2O2. The results indicate that 60-mM H2O2 increased the accumulation of arsenic, iron and sodium content in the leaves of F. deltoidea. On the other hand, 8-mM H2O2 significantly enhanced the accumulation of arsenic, iron, calcium and potassium content in the syconium of F. deltoidea plants. In addition, H2O2 treatment did not produce any significant effects on antimony and magnesium accumulation in the leaves or the syconium of F. deltoidea plants. The results show that the F. deltoidea plant has strong antidiabetic properties and its α-glucosidase activity increased in treated plants compared to standard acarbose. Hydrogen peroxide, particularly in concentrations of 16 and 30 mM, increased the antioxidant activity, total phenolic and flavonoid content and the vitexin and isovitexin content. There was a positive correlation between antioxidant activity with total phenol and total flavonoid content in H2O2-treated plants. The quantitative analysis by HPTLC indicates that the amount of vitexin and isovitexin increased with the higher concentrations of H2O2. From this study, it can be concluded that spraying 16 and 30-mM H2O2 once a week enhances growth, mineral accumulation and stimulates bioactive compounds of the F. deltoidea plants.


1924 ◽  
Vol 39 (5) ◽  
pp. 745-755 ◽  
Author(s):  
Oswald T. Avery ◽  
James M. Neill

In the present work on oxidation and reduction by sterile extracts of pneumococcus, the preparations employed contain among other constituents, a hemolytic substance the properties of which have been described by Cole (1, 2) in his studies on pneumococcus hemotoxin. Pneumococcus extracts prepared by the methods described are actively hemolytic, 0.005 cc. of extract causing complete lysis of 2.5 cc. of a 1 per cent suspension of red cells from rabbit blood. This hemolytic property of pneumococcus extracts is destroyed by 10 minutes exposure to 55°C. When pneumotoxin-containing extracts are protected from the action of molecular oxygen, their hemolytic activity remains unimpaired for considerable periods of time. In the presence of air, on the other hand, the stability of the hemolytic substance depends upon whether the particular type of extract contains a "complete" or "incomplete" oxidation-reduction system. Sterile broth extracts of unwashed pneumococci are reactive with molecular oxygen, and as a result of this union peroxide is formed whenever these extracts are exposed to air. The hemolytic activity of "complete" extracts of this type is rapidly decreased and finally destroyed in the presence of molecular oxygen. On the other hand, the "incomplete" type of extract prepared by saline extraction of washed pneumococci may be exposed to air with little or no loss of hemolytic power. This "incomplete" washed cell extract, unless reactivated, does not undergo autoxidation in the presence of air; under these circumstances peroxide is not formed and the hemolytic activity of this type of extract is not impaired by exposure to air. The stability of the hemolytic agent in the "incomplete" type of extract is evidence that this substance is itself not reactive with or affected by molecular oxygen, even in the presence of the cell enzymes. The destruction of the same hemolytic substance in extracts capable of undergoing autoxidation may be ascribed to the action of some peroxide formed by the union of molecular oxygen with easily oxidized or autoxidizable substances of the extract. It is now known that a peroxide, having the reactions of hydrogen peroxide, accumulates in sterile pneumococcus extracts during oxidation. It has been shown in the present study that the addition of preformed hydrogen peroxide destroys the hemolytic activity of pneumococcus extracts, although higher concentrations were required than were detected in oxidized extracts themselves. These facts and the known action of superoxides in analogous types of reaction make it seem not unlikely that the active agent in the destruction of pneumotoxin in oxidized cell extracts may be a peroxide; either hydrogen peroxide or some higher organic peroxide formed during autoxidation of the extract.


2012 ◽  
Vol 717-720 ◽  
pp. 753-756
Author(s):  
Eduardo Pitthan ◽  
Silma A. Corrêa ◽  
Rodrigo Palmieri ◽  
Gabriel Vieira Soares ◽  
Henri I. Boudinov ◽  
...  

The effect of sequential thermal treatments with growth/removal steps of SiO2 films intercalated with hydrogen peroxide treatments on the SiO2/4H-SiC interfacial region thickness were investigated on both Si and C faces. In the Si face case, samples that were submitted to more H2O2 treatments presented thinner interfacial region thicknesses. In the C face case, on the other hand, no significant alteration in this region was observed.


1997 ◽  
Vol 17 (2) ◽  
pp. 97-108 ◽  
Author(s):  
Yuichi Shimizu ◽  
Shun'ichi Sugimoto ◽  
Shunichi Kawanishi ◽  
Nobutake Suzuki

Targeting the selective and direct synthesis of tartaric acid (TA), the photochemical reactions of maleic acid (MA) solutions containing H2O2. in various solvents have been investigated using four wavelengths in the UV region between 193 and 351 nm, with high intensity from an excimer laser. All the laser irradiations in H2O resulted in the direct synthesis of TA with lower selectivity and it was found that, with XeF-laser (351 nm) irradiation in 1,4-dioxane, TA is selectively and directly synthesized from MA containing H2O2 of lower concentration at room temperature. On the other hand, none of the irradiations in methanol, N,N-dimethylformamide, acetonitrile, and tetrahydrofuran gave the selective formation of TA. On the basis of these results, the reaction scheme for the selective formation of TA is discussed.


2017 ◽  
Vol 12 (1) ◽  
pp. 10
Author(s):  
Nilawati Widjaya

<p>This objective of the research was to know the effect of soaking with hydrogen<br />peroxide on weight reduction, haugh unit and albumen index of duck eggs during storage at room temperature. The research was designed as Completely Randomize Design (CRD) wtih four treatments and six replicates each. The treatments were: soaking with aquades, soaking with 1, 2, and 3% of hydrogen The data were analyzed by analysis of variance and continued with Duncan Multiple Range Test. The results indicated that soaking with hydrogen peroxyde influended the egg weight, Haugh Unit and albumen index at chamber temperature during the storage. Soaking with 1% hydrogen peroxide showed the best results compared with the other treatments.<br />Key words: soaking, hydrogen peroxide, weight decrease, haugh unit, albumen index</p>


PEDIATRICS ◽  
1973 ◽  
Vol 52 (2) ◽  
pp. 309-309
Author(s):  
C. Warren Bierman

Dr. Bergner is quite correct in pointing out that skin testing with a freshly prepared penicillin solution will select out only about 30% of patients who are anaphylacticly sensitive to penicillin.1 On the other hand, the use of a sterile solution of benzylpenicillin diluted with alkaline buffered saline (pH 7.6) and permitted to stand at room temperature for at least two weeks appreciably increases the number of patients so detected.2 We would agree that the availability of a penicilloyl polylysine (PPL) testing solution and a stabilized minor determinent mixture (MDM) would greatly enhance the armamentarium of the clinician to detect anaphylactic sensitivity to penicillin.3


2000 ◽  
Vol 113 (21) ◽  
pp. 3795-3803 ◽  
Author(s):  
A. Di Nardo ◽  
R. Gareus ◽  
D. Kwiatkowski ◽  
W. Witke

Profilins are a conserved family of proteins participating in actin dynamics and cell motility. In the mouse, two profilin genes are known. Profilin I is expressed universally at high levels, while profilin II is expressed mainly in the brain. Here we describe the occurrence of two mouse profilin II isoforms, A and B, which are derived by alternative splicing. They are identical through residue 107 of the protein, but then have distinct C-terminal sequences. Profilin IIA binds to poly-L-proline and actin with high affinity similar to profilin I. Profilin IIB on the other hand does not bind to actin and the affinity for poly-L-proline is greatly diminished. However, tubulin was found to bind to GST-profilin IIB, and in vivo GFP-profilin IIB was recruited to spindles and asters during mitosis in HeLa cells. Our results indicate unexpected diversity in the functions of the profilin family of proteins, and suggest that in mouse profilin IIA is intimately involved in actin dynamics, while profilin IIB associates with other cytoskeletal components.


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