Structurally manipulated antioxidant peptides derived from wheat bran: Preparation and identification.

Bioactive peptide's development is facing two challenges in terms of its lower yield and limited understanding of structurally orientated functionality. Therefore, peptides were prepared from wheat bran via a cocktail enzyme for achieving a higher level of hydrophobic amino acids than traditional method. The obtained peptides exhibited great antioxidant activities against H2O2-induced oxidative stress in HepG2 cells. Among them, 91 bioactive peptides were selected through the virtual screening, and their N-terminal and C-terminal contained many hydrophobic amino acids. Then the peptides with capacity to interact with Keap1 were identified by in silico simulation, because Keap1 acts as a sensor of redox insults. The results revealed that peptides DLDW and DLGL demonstrated the highest binding affinities, and a bridge was formed between Asp of DLGL and Arg415 of Klech domain, contributing to interfering Keap1-Nrf2 interaction. These findings implied a potential application of wheat bran peptides as nutraceuticals and health-promoting ingredients.

Structural property of extractable proteins and polysaccharides in wheat bran following a dual-enzymatic pretreatment and corresponding functionality.

The current study applied dual-enzymatic treatment via alcalase and Bacillus velezensis hydrolase for enhancing extraction of proteins and polysaccharides from wheat bran and modifying their corresponding structure. Results indicated the aqueous extract by enzymatic pretreatment (referred as EHWB) had an increased content of soluble substance, in which 18.5 % increased for carbohydrates and 11.4 % increased for proteins in the extract compared to the aqueous extract without enzymes (labeled as AEWB). Furthermore, compositions with lower molecular weight of 130 kDa and < 21.1 kDa for polysaccharides and proteins, respectively, were found in EHWB. Interestingly, EHWB had a twice higher radicals scavenging than that of AEWB, and digestive property indicated EHWB had a greater peptides production although glucose release was lower in gastric phase. Importantly, this is the first study to reveal that gut microbiota fermentation of EHWB resulted in faster generation of short-chain fatty acids at initial fermentation stage (6 h), followed a higher generation of butyrate at final fermentation stage (24 h). This fermentation property might be associated with its presence of lower molecular weight substrates and even the changes in the molecular structure induced by the enzymes. This study highlights a novel approach for developing a value-added product from wheat bran.

Mapping the metabolic characteristics of probiotic-fermented Ganoderma lucidum and its protective mechanism against Cd-induced nephrotoxicity.

An animal model of Cd-induced kidney damage was designed to investigate the nephroprotective potential of the probiotic-fermented Ganoderma lucidum (FGL) via metabonomic analysis. The results showed that FGL enhanced sugar and amino acid metabolism. The interaction of Ganoderma lucidum (GL) and probiotics efficiently elevated short-chain fatty acid production following gut microbiota fermentation. The current data revealed that the FGL intervention alleviated Cd-induced nephrotoxicity via elevating the activity of antioxidant enzymes and decreasing the levels of pro-inflammatory and apoptotic factors. Based on transcriptome analysis, FGL intervention mediated renal dysfunction via decreasing the expressions of Nos2, Tnfsf14, S100a9, Map3k6 and Hk3, which were involved in oxidative stress, inflammatory response and the apoptosis process. The current study highlights a new approach for achieving positive nephroprotection via natural product intervention.

Chemical characterization, antioxidant and immunomodulatory activities of acetylated polysaccharides from Cyperus esculentus.

This research was designed to characterize the structure of Cyperus esculentus polysaccharide (CEP) and its acetylated one (ACEP), and then investigated the effects of acetylation on the changes in physicochemical properties, thermal stability, antioxidant and immunomodulatory activities. Results showed that CEP and ACEP were heteropolysaccharides consisting of glucose, mannose, arabinose and xylose. The main chain of CEP included α-1,4-Glcp residues with the branching points at the O-6 position of the α-1,6-Manp residues. Acetyl groups were substituted at the O-2 and O-6 positions of some glucose residues. Meanwhile, the acetylation remarkably improved the polysaccharides thermal stability, and the ACEP exhibited a greater antioxidant activity. Furthermore, CEP and ACEP were proved to protect RAW 264.7 cells against LPS-induced inflammation by improving cellular morphology and decreasing reactive oxygen species secretion. This study may highlight a new approach for developing a high value-added ingredient from C. esculentus for functional food industry.