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To obtain hydrolysates with high degree of hydrolysis (DH) and scavenging radical activity, tilapia skin gelatin (TSG) was hydrolyzed by properase E and multifect neutral. The optimum hydrolysis condition of each enzyme was determined using the orthogonal experiment, and double-enzyme hydrolysis was further applied. The results showed the tilapia skin gelatin hydrolysate (TSGH) obtained by progressive hydrolysis using multifect neutral and properase E had the highest DH and hydroxyl radical scavenging activity. The IC50 values of TSGH on scavenging 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical, superoxide anion radical (・O2) and hydroxyl radical (・OH) activities were also determined. TSGH was further purified using gel filtration chromatography, ion exchange chromatography, and RP-HPLC. The peptides were identified using nano-LC-ESI mass spectrometry. Finally, two antioxidant peptides were identified and the amino acid sequences were Glu-Gly-Leu (317.33 Da) and Tyr-Gly-Asp-Glu-Tyr (645.21 Da), respectively. The IC50 values of two peptides on hydroxyl radical scavenging activities were 4.61 μgmL−1and 6.45 μgmL−1, respectively. Therefore, the results demonstrated that the hydrolysates of TSG prepared by multifect neutral and properase E could serve as a source of peptides with high antioxidant activity. It provided a scientific basis for the preparation of antioxidant peptides. [Copyright &y& Elsevier]

Photocatalyzed alkylsulfonylation of unactivated alkenes using DABCO. (SO2)2 and thianthrenium salts via a distal heteroaryl migration process has been developed, which provides a new means of synthesizing a variety of valuable alkylsulfonyl-substituted compounds. These alkylsulfonyl radicals couple with unactivated alkenes to undergo efficient intermolecular reactions, followed by distal heteroaryl migration. This mild catalytic method is tolerant of functional groups and affords medicinally relevant alkylsulfonylated heterocycles. [ABSTRACT FROM AUTHOR]

A green efficient photoredox-catalyzed decarboxylative alkynylation of carboxylic acids with alkynyl bromides has been developed. This broadly applicable protocol is presented wherein a-amino, aliphatic and α-oxy acids are converted into useful alkynylation products. The commercially-available organic photocatalyst 4CzIPN is used as the photocatalyst, organic base DBU is utilized as the base, and DMSO serves as solvent. This strategy features mild conditions, is metal-free, and is environmentally friendly. The batch and continuous-flow protocols described were applied to obtain a broader substrate scope of functionalization (more than 50 examples). Furthermore, we demonstrate that the use of microflow technology enhanced and intensified the reaction process, achieving significantly reduced reaction times (i.e., 10 min of residence time). [ABSTRACT FROM AUTHOR]

• Hepatitis E virus infection has become a global concern, especially in pregnant women. • A large cohort of pregnant women (n=19,762) were investigated for HEV prevalence. • Adverse pregnancy outcomes were found in genotype 4 HEV-infected pregnant women. • Age, gravidity and parity are associated with the prevalence of HEV during pregnancy. Hepatitis E virus (HEV) infection has become a global concern, especially in pregnant women. However, the association between HEV prevalence and age, gravidity and parity of pregnant women remains unclear. Pregnant women (n=19,762) were enrolled for HEV prevalence and associated adverse pregnancy outcomes investigation in Qujing City, Yunnan Province of China from May 2019 to December 2020. The seroprevalence of HEV was 11.6% (2,297/19,762; 95% CI:11.2%–12.1%). About 11.4% (2,247/19,762; 95% CI:10.9%–11.8%) were positive for anti-HEV IgG antibody, 0.1% (22/19,762; 95% CI:0.1%–0.2%) were positive for anti-HEV IgM antibody, and 0.1% (28/19,762; 95% CI:0.1%–0.2%) were positive for both anti-HEV IgM and IgG antibodies. Sixty-one out of 2,297 anti-HEV-antibodies-positive pregnant women were positive for HEV RNA. Phylogenetic analysis revealed that all HEV isolates from pregnant women belong to genotype 4. Age, gravidity and parity are associated with increased prevalence of HEV. Pregnant women positive for HEV-IgG antibody bear a higher risk for an adverse pregnancy history and liver injury with elevated alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels than anti-HEV-negative pregnant women. Furthermore, seropositive pregnant women suffered a higher adverse maternal outcomes risk (crude odds ratio [cOR]=1.29; 95% CI: 1.16–1.43; adjusted odds ratio [aOR]=1.40, 95% CI: 1.25–1.55 for anti-HEV-IgG-positive pregnant women and cOR=1.38, 95% CI: 1.02–1.86; aOR=1.43, 95% CI: 1.05–1.95 for anti-HEV-IgM-positive pregnant women) and fetal outcomes risk (cOR=1.80, 95% CI: 1.61–2.01; aOR=1.77, 95% CI: 1.57–1.99) than anti-HEV-negative pregnant women. Adverse pregnancy outcomes of HEV infection are aggravated by age, gravidity and parity. In this study, we demonstrated high prevalence of HEV in pregnancy women in China, and HEV infection can cause various adverse maternal and neonatal outcomes. [ABSTRACT FROM AUTHOR]