Chemical Basis and Molecular Mechanism of Aged Qingzhuan Tea Alleviating DSS-Induced Colitis.

Scope: Inflammatory bowel disease (IBD) poses a serious threat to human health. Qingzhuan tea (QZT), especially aged QZT, was concerned to have a potential effect on the prevention of colitis. In this study, we aim to assess the feasibility of different aged QZT on the alleviation of colitis induced by DSS.

Theabrownin/whey protein isolate complex coacervate strengthens CC cell proliferation via modulation of energy metabolism and mitochondrial apoptosis.

Theabrownin (TB)-whey protein isolate (WPI) complex coacervates (TW) were firstly prepared to investigate the regulatory effects on skeletal muscle. The binding of TB to WPI reached saturation with the strongest electrostatic interaction at the ratio of 10:1. The formation of TW was driven by electrostatic interactions with the aid of hydrogen bonding and hydrophobic interactions, and the digestion behavior of TW was investigated based on in vitro gastrointestinal and CaCO cell models.

Metabolic function and quality contribution of tea-derived microbes, and their safety risk in dark tea manufacture.

Microbial fermentation, especially the microbes involved, plays a crucial role in the quality formation of dark tea. Over the last decade, numerous microbes have been isolated from dark tea and in turn, applied to dark tea manufacture through pure-strain, mixed-strain, and enhanced fermentation. This article systematically summarizes the specific metabolic function and quality contribution of tea-derived microbes, with special attention paid to their safety risk.

Co-occurrence network and functional profiling of the bacterial community in the industrial pile fermentation of Qingzhuan tea: Understanding core functional bacteria.

The distinct quality of Qingzhuan tea is greatly influenced by the bacterial community but was poorly characterized. Therefore, this study investigated the Co-occurrence network and functional profiling of the bacterial community, with special attention paid to core functional bacteria in the industrial pile fermentation. Microbiomics analysis indicated that Klebsiella and Pantoea dominated raw tea leaves, and were rapidly replaced by Pseudomonas in pile fermentation, but substituted mainly by Burkholderia and Saccharopolyspora in final fermented tea.

Exploring core functional fungi driving the metabolic conversion in the industrial pile fermentation of Qingzhuan tea.

The distinct sensory quality of Qingzhuan tea is mainly formed in pile fermentation by a group of functional microorganisms but the core functional ones was poorly characterized. Therefore, this study investigated the dynamic changes in the fungal community and metabolic profile by integrating microbiomics and metabolomics, and explored the core functional fungi driving the metabolic conversion in the industrial pile fermentation of Qingzhuan tea. Indicated by microbiomics analysis, Aspergillus dominated the entire pile-fermentation process, while Thermoascus, Rasamsonia, and Cylindrium successively abounded in the different stages of the pile fermentation.

Preparation, Characterization, and Antioxidant Properties of Selenium-Enriched Tea Peptides.

The research on the activity of selenium (Se)-enriched agricultural products is receiving increasing attention since Se was recognized for its antioxidant activities and for its enhancement of immunity in trace elements. In this study, antioxidant Se-containing peptides, namely, Se-TAPepI-1 and Se-TAPepI-2, were optimally separated and prepared from Se-enriched tea protein hydrolysates by ultrafiltration and Sephadex G-25 purification, and subsequently, their physicochemical properties, oligopeptide sequence, and potential antioxidant mechanism were analyzed. Through the optimization of enzymatic hydrolysis conditions, the Se-enriched tea protein hydrolyzed by papain exhibited a better free radical scavenging activity.

State-of-the-art review of theabrownins: from preparation, structural characterization to health-promoting benefits.

As far as health benefit is concerned, dark tea is one of the best beverages in the world. Theabrownins are the major ingredient contributing to the health benefits of dark tea and known as "the soft gold in dark tea." A growing body of evidence indicated that theabrownins are macromolecular pigments with reddish-brown color and mellow taste, and mainly derived from the oxidative polymerization of tea polyphenols.

Gut Microbiota Differentially Mediated by Qingmao Tea and Qingzhuan Tea Alleviated High-Fat-Induced Obesity and Associated Metabolic Disorders: The Impact of Microbial Fermentation.

Although dark tea is a unique microbial-fermented tea with a high reputation for having an antiobesity effect, little is known about the effect of microbial fermentation on tea leaves' antiobesity properties. This study compared the antiobesity effects of microbial-fermented Qingzhuan tea (QZT) and unfermented Qingmao tea (QMT), providing insight into their underlying mechanisms associated with gut microbiota. Our results indicated that the supplementation of QMT extract (QMTe) and QZT extract (QZTe) displayed similar antiobesity effects in high-fat diet (HFD)-fed mice, but the hypolipidemic effect of QZTe was significantly stronger than that of QMTe.

The post-discharge coping difficulty of puerperal women in a middle and low-income tourist city during the COVID-19 pandemic.

Background: Since the coronavirus disease 2019 (COVID-19) pandemic outbreak, the incidence of mental health problems in perinatal women has been high, and particularly prominent in China which was the first country affected by COVID-19. This paper aims to investigate the current situation and the related factors of maternal coping difficulties after discharge during COVID-19.

Methods: General information questionnaires (the Perinatal Maternal Health Literacy Scale, Postpartum Social Support Scale and Post-Discharge Coping Difficulty Scale-New Mother Form) were used to investigate 226 puerperal women in the third week of puerperium.

Recent advances in the utilization of tea active ingredients to regulate sleep through neuroendocrine pathway, immune system and intestinal microbiota.

Sleep disorders have received widespread attention nowadays, which have been promoted by the accelerated pace of life, unhealthy diets and lack of exercise in modern society. The chemical medications to improve sleep has shown serious side effects and risks with high costs. Therefore, it is urgent to develop efficient nutraceuticals from natural sources to ensure sleep quality as a sustainable strategy.

Theoretically probing the possible degradation mechanisms of an FeNC catalyst during the oxygen reduction reaction.

For the FeNC catalyst widely used in the oxygen reduction reaction (ORR), its instability under fuel cell (FC) operating conditions has become the biggest obstacle during its practical application. The complexity of the degradation process of the FeNC catalyst in FCs poses a huge challenge when it comes to revealing the underlying degradation mechanism that directly leads to the decay in ORR activity. Herein, using density functional theory (DFT) and ab initio molecular dynamics (AIMD) approaches and the FeN moiety as an active site, we find that during catalyzing the ORR, Fe site oxidation in the form of *Fe(OH), in which 2OH* species are adsorbed on Fe on the same side of the FeN plane, results in the successive protonation of N and then permanent damage to the FeN moiety, which causes the leaching of the Fe site in the form of Fe(OH) species and a sharp irreversible decline in the ORR activity.

Dynamic changes of metabolic profile and taste quality during the long-term aging of Qingzhuan Tea: The impact of storage age.

Qingzhuan tea (QZT) with longer aging year is usually believed to have higher quality and commercial value. In this study, a 20 years sequence of aged QZT were subjected to an electronic tongue and liquid chromatography-mass spectrometry to investigate the effect of storage age on its metabolic profile and taste quality. The changes in both taste quality and metabolic profile exhibited a parabolic trend in the 20 years of QZT aging and reached the maximum at the 10th year.

Novel monoclonal antibody-sandwich immunochromatographic assay based on FeO/Au nanoparticles for rapid detection of fish allergen parvalbumin.

In this study, a rapid sandwich immunochromatographic assay (ICA) was developed to detect parvalbumin (PV). Firstly, two optimum primary monoclonal antibody (mAb) against PV had been screened out: mAb1 was used as the capture antibody, and mAb2 conjugated to FeO/Au nanoparticles (FeO/AuNPs) that served as a detection reagent. Using this pair of mAbs, a sandwich ICA strip based on FeO/AuNPs was developed.

Effect of degree of milling on the cadmium in vitro bioaccessibility in cooked rice.

Cadmium (Cd) contamination in rice grain is common worldwide. This study investigated the effect of degree of milling (DM) on the reduction of Cd in cooked rice grain and porridge (rice-to-water ratios 1:1.6 and 1:10, respectively) and Cd in vitro bioaccessibility.

Theoretical research on the oxidation mechanism of doped carbon based catalysts for oxygen reduction reaction.

To understand the essential reasons of poor durability and rapid initial performance loss of heteroatom doped graphene catalysts during the electrochemical oxygen reduction reaction (ORR) process, it is necessary to explore the detailed mechanism of carbon active site oxidation reaction (COR) at different electrode potentials, as it may greatly influence the ORR activity. Herein, density functional theory (DFT) calculation is used to investigate all possible COR mechanisms, including Direct-COR and Indirect-COR, on four typical doped-graphene, and understand the competing relation between COR and ORR from a thermodynamic point of view. Our systematic calculations found that the Direct-COR is affected directly by the structural stability of doped-graphene relative to pure graphite, and the Indirect-COR can be accelerated largely by the ORR process due to the ORR intermediate, such as O and OOH.