A Comparative Study on Reactions of Hydrogen Peroxide and Peracetic Acid with Lignin Chromophores. Part 2. The Reaction of Stilbene-Type Model Compounds

Holzforschung ◽  
2000 ◽  
Vol 54 (2) ◽  
pp. 153-158 ◽  
Author(s):  
George X. Pan ◽  
Liam Spencer ◽  
Gordon J. Leary

Summary The reactions of three hydroxy- and/or methoxy-substituted stilbenes with hydrogen peroxide and peracetic acid have been investigated. Overall, the reactivity of stilbenes was greater towards peracetic acid than towards hydrogen peroxide. Among the stilbene model compounds studied, 4-hydroxystilbene (I) was virtually unreactive to hydrogen peroxide, but was oxidized by peracetic acid to a varying extent that was highly pH-dependent. 4,4′-Dihydroxy-3,3′-dimethoxystilbene (II) and 3,5-dimethoxy-4-hydroxystilbene (III) showed a greater reactivity to either hydrogen peroxide or peracetic acid than 4-hydroxystilbene (I).

2002 ◽  
Vol 41 (15) ◽  
pp. 3518-3525 ◽  
Author(s):  
F. López ◽  
M. E. Eugenio ◽  
M. J. Díaz ◽  
I. Pérez ◽  
L. Jiménez

Holzforschung ◽  
2000 ◽  
Vol 54 (2) ◽  
pp. 144-152 ◽  
Author(s):  
George X. Pan ◽  
Liam Spencer ◽  
Gordon J. Leary

Summary The reactions of chromophoric model compounds of the coniferaldehyde type with hydrogen peroxide and peracetic acid have been investigated in relation to lignin-retaining bleaching. Analysis of the main reaction products indicated that the side chain of coniferaldehyde could cleave either between the α, β double bond or between the β, γ bond. Comparison of possible reaction pathways to the formation of oxidation products from hydrogen peroxide and peracetic acid suggested that peracetic acid is more effective than hydrogen peroxide. Advantages of peracetic acid over hydrogen peroxide include a faster rate of reaction, more efficient utilization of the bleaching agent and less likelihood of producing new chromophores.


Author(s):  
Shu-shu Zhong ◽  
Jun Zhang ◽  
Ze-hua Liu ◽  
Zhi Dang ◽  
Yu Liu

Arylsulfatase and β-glucuronidase are two important enzymes in human, which play important role on dynamic equilibrium of steroidal estrogens. This work probably for the first time reported that hydrogen peroxide (H2O2), hypochlorite and peracetic acid (PAA) could effectively inhibit the activities of arylsulfatase and/or β-glucuronidase. The 50 percent of inhibitions (IC50) of H2O2, and PAA on arylsulfatase were found to be 142.90±9.00, 91.83±10.01, and 43.46±2.92 μM, respectively. The corresponding respective IC50 of hypochlorite and PAA on β-glucuronidase were 704.90±41.40 and 23.26±0.82 μM, while H2O2 showed no inhibition on β-glucuronidase. It was further revealed that the inhibition of hypochlorite on both arylsulfatase and β-glucuronidase was irreversible. On the contrary, the inhibition by H2O2 and PAA was reversible. Moreover, it was found that the inhibitions of arylsulfatase and/or β-glucuronidase by these three chemicals were pH-dependent, among which the inhibition by H2O2 was competitive and non-competitive for PAA. In general, H2O2 and hypochlorite can be endogenously produced in human, which suggested that the two compounds are potential endocrine disruption compounds (EDCs) as they can cause endocrine disruption via inhibition of arylsulfatase and β-glucuronidase. This work further indicated that any agent that can induce production of H2O2 or hypochlorite in human is potential EDC, which explains why some EDCs with very weak or no estrogenic potency can cause endocrine disruption that confirmed in epidemiological studies.


ACS Omega ◽  
2021 ◽  
Author(s):  
Shu-shu Zhong ◽  
Jun Zhang ◽  
Ze-hua Liu ◽  
Zhi Dang ◽  
Yu Liu

Pathogens ◽  
2020 ◽  
Vol 10 (1) ◽  
pp. 24
Author(s):  
Akikazu Sakudo ◽  
Daiki Anraku ◽  
Tomomasa Itarashiki

Prion diseases are proteopathies that cause neurodegenerative disorders in humans and animals. Prion is highly resistant to both chemical and physical inactivation. Here, vaporized gas derived from a hydrogen peroxide–peracetic acid mixture (VHPPA) was evaluated for its ability to inactivate prion using a STERIACE 100 instrument (Saraya Co., Ltd.). Brain homogenates of scrapie (Chandler strain) prion-infected mice were placed on a cover glass, air-dried, sealed in a Tyvek package, and subjected to VHPPA treatment at 50–55 °C using 8% hydrogen peroxide and <10% peracetic acid for 47 min (standard mode, SD) or 30 min (quick mode, QC). Untreated control samples were prepared in the same way but without VHPPA. The resulting samples were treated with proteinase K (PK) to separate PK-resistant prion protein (PrPres), as a marker of the abnormal isoform (PrPSc). Immunoblotting showed that PrPres was reduced by both SD and QC VHPPA treatments. PrPres bands were detected after protein misfolding cyclic amplification of control but not VHPPA-treated samples. In mice injected with prion samples, VHPPA treatment of prion significantly prolonged survival relative to untreated samples, suggesting that it decreases prion infectivity. Taken together, the results show that VHPPA inactivates prions and might be applied to the sterilization of contaminated heat-sensitive medical devices.


Endoscopy ◽  
2008 ◽  
Vol 40 (03) ◽  
pp. 231-231 ◽  
Author(s):  
R. Coriat ◽  
U. Chaput ◽  
Z. Ismaili ◽  
S. Chaussade

2017 ◽  
Vol 83 (21) ◽  
Author(s):  
Kosei Kawasaki ◽  
Yoichi Kamagata

ABSTRACTPreviously, we reported that when agar is autoclaved with phosphate buffer, hydrogen peroxide (H2O2) is formed in the resulting medium (PT medium), and the colony count on the medium inoculated with environmental samples becomes much lower than that on a medium in which agar and phosphate are autoclaved separately (PS medium) (T. Tanaka et al., Appl Environ Microbiol 80:7659–7666, 2014,https://doi.org/10.1128/AEM.02741-14). However, the physicochemical mechanisms underlying this observation remain largely unknown. Here, we determined the factors affecting H2O2formation in agar. The H2O2formation was pH dependent: H2O2was formed at high concentrations in an alkaline or neutral phosphate buffer but not in an acidic buffer. Ammonium ions enhanced H2O2formation, implying the involvement of the Maillard reaction catalyzed by phosphate. We found that other gelling agents (e.g., gellan and κ-carrageenan) also produced H2O2after being autoclaved with phosphate. We then examined the cultivability of microorganisms from a fresh-water sample to test whether catalase and pyruvate, known as H2O2scavengers, are effective in yielding high colony counts. The colony count on PT medium was only 5.7% of that on PS medium. Catalase treatment effectively restored the colony count of PT medium (to 106% of that on PS medium). In contrast, pyruvate was not as effective as catalase: the colony count on sodium pyruvate-supplemented PT medium was 58% of that on PS medium. Given that both catalase and pyruvate can remove H2O2from PT medium, these observations indicate that although H2O2is the main cause of reduced colony count on PT medium, other unknown growth-inhibiting substances that cannot be removed by pyruvate (but can be by catalase) may also be involved.IMPORTANCEThe majority of bacteria in natural environments are recalcitrant to laboratory culture techniques. Previously, we demonstrated that one reason for this is the formation of high H2O2levels in media prepared by autoclaving agar and phosphate buffer together (PT medium). In this study, we investigated the factors affecting H2O2formation from agar. H2O2formation is pH dependent, and ammonium ions promote this phosphate-catalyzed H2O2formation. Amendment of catalase or pyruvate, a well-known H2O2-scavenging agent, effectively eliminated H2O2. Yet results suggest that growth-inhibiting factor(s) that cannot be eliminated by pyruvate (but can be by catalase) are present in PT medium.


Carbon ◽  
2011 ◽  
Vol 49 (8) ◽  
pp. 2842-2851 ◽  
Author(s):  
M.H.M.T. Assumpção ◽  
R.F.B. De Souza ◽  
D.C. Rascio ◽  
J.C.M. Silva ◽  
M.L. Calegaro ◽  
...  

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