Effect of modified starches on the quality of skins of glutinous rice dumplings.

This study aimed to investigate the influence of modified starches on the quality of skins of glutinous rice dumplings (SGRDs), including changes in textural properties, pasting parameters, microstructure, color, transparency, and sensory quality. The results showed that the addition of a single acetylated-modified cassava or potato starch or composite modified cassava and potato starch in a ratio of 2:1 can improve the quality of SGRDs. The springiness and lightness of SGRDs increased, and the transparency increased from 3.

Thermally Methanol Oxidation via the Mn@CoO(111) Facet: Non-CO Reaction Pathway.

CoO, as the support of single-atom catalysts, is effective in electron-structure modulation to get distinct methanol adsorption behaviors and adjustable reaction pathways for the methanol oxidation reaction. Herein, we considered the facets that constitute a Co vacancy of the CoO(111) facet and a foreign metal atom M (M = Fe, Ni, Cu, Ru, Rh, Pd, Ag, Os, Ir, Pt, Au, Mn) leading to single-atom catalysts. The Mn@CoO(111) facet is the facet considered the most favorable among all of the possible terminations.

The effects of an innovative pulping technique of synchronously pulping and gelatinizing treatment on raw materials properties, oenological parameters, fermentation process, and flavor characteristics of glutinous rice wine.

Unlabelled: Liquid-state fermentation has been increasingly applied in the industrial glutinous rice wine (GRW) production. However, products brewed by this emerging technique possess some deficiencies in flavor quality. Therefore, this study firstly developed and optimized an innovative pulping technique by the synchronously pulping and gelatinizing treatment (Process I) to improve GRW flavor quality, and then revealed the influences of Process I on raw materials properties, oenological parameters, fermentation process, and flavor characteristics of GRW.

Effects of modernized fermentation on the microbial community succession and ethyl lactate metabolism in Chinese baijiu fermentation.

Modernized mechanization and intelligent transformation are the trends of Chinese baijiu industry development. However, these changes affect the operational environment, which lead to the decreased metabolism of esters during baijiu fermentation, especially for ethyl lactate. Ethyl lactate is an important flavor compound in most types of baijiu, which is mainly produced by esterification of lactic acid and ethanol.

Computational insight into biotransformation of halophenols by cytochrome P450: Mechanism and reactivity for epoxidation.

Halophenols (XPs) have aroused great interests due to their high toxicity and low biodegradability. Previous experimental studies have shown that XPs can be catalytically transformed into epoxides and haloquinones by cytochrome P450 enzymes (CYPs). However, these metabolites have never been detected directly.

Imidazoline Gemini Surfactants as Corrosion Inhibitors for Carbon Steel X70 in NaCl Solution.

The Gemini imidazoline surfactants were synthesized from a series of saturated fatty acids. Electrochemical impedance spectroscopy (EIS), polarization curve, and quantum chemistry methods were used to study the corrosion inhibition behavior of Gemini imidazoline surfactants for X70 carbon steel in NaCl solution. Results reveal that such kind of surfactants has an outstanding inhibition effect on carbon steel X70 in NaCl solution and that the restrained efficiency of Gemini imidazoline in an alkaline solution is better than that in a neutral solution.

Chloroplast genome sequence of a yellow colored rice ( L.): insight into the genome structure and phylogeny.

Colored rice is gaining popularity due to its use in creative agriculture and the value of healthy consumption. However, the quality and yield characteristics of most rice varieties still need to be improved. Revealing the genetic background of colored rice is of great significance to promote crop improvement.

Mechanistic Insights into the Oxidative Rearrangement Catalyzed by the Unprecedented Dioxygenase ChaP Involved in Chartreusin Biosynthesis.

ChaP is a non-heme iron-dependent dioxygenase belonging to the vicinal oxygen chelate (VOC) enzyme superfamily that catalyzes the final α-pyrone ring formation in the biosynthesis of chartreusin. In contrast to other common dioxygenases, for example, 2,3-catechol dioxygenase which uses the dioxygen molecule as the oxidant, ChaP requires the flavin-activated oxygen (O) as the equivalent. Previous experiments showed that the ChaP-catalyzed ring rearrangement contains two successive C-C bond cleavages and one lactonization; however, the detailed reaction mechanism is unknown.

Mechanism of Uncoupled Carbocyclization and Epimerization Catalyzed by Two Non-Heme Iron/α-Ketoglutarate Dependent Enzymes.

The non-heme iron/α-ketoglutarate dependent enzymes SnoK and SnoN from are involved in the biosynthesis of anthracycline nogalamycin. Although they have similar active sites, SnoK is responsible for carbocyclization whereas SnoN solely catalyzes the hydroxyl epimerization. Herein, we performed docking, molecular simulations, and a series of combined quantum mechanics and molecular mechanics (QM/MM) calculations to illuminate the mechanisms of two enzymes.

An aerobic detoxification photofermentation by Rhodospirillum rubrum for converting soy sauce residue into feed with moderate pretreatment.

This paper reports an effective process for converting soy sauce residue into feeds by combining moderate acid hydrolysis and ammonization with Rhodospirillum rubrum fermentation. After pretreatment with dilute sulfuric or phosphoric acid (1%, w/w) at 100 °C, materials were subjected to fermentation under several gases (N, CO, and air) and different light intensities in a 2-L fermentor. Following sulfuric acid treatment, the true protein increased from 188 to 362 g kg and the crude fiber decreased from 226 to 66 g kg after fermentation at 0.

QM/MM studies on the calcium-assisted β-elimination mechanism of pectate lyase from bacillus subtilis.

Pectate lyase utilizes the anti-β-elimination chemistry to catalyze the cleavage of α-1,4 glycosidic bond between -galacturonate regions during the degradation of plant polysaccharide pectin. We report here detailed mechanistic studies of the Bacillus subtilis pectate lyase (BsPel) using QM/MM calculations. It was found that the residue Arg279 serves as the catalytic base to abstract the α-proton from C atom of substrate Ada2 subsite, forming an unstable carbanion intermediate.

Quantum Mechanics and Molecular Mechanics Study of the Catalytic Mechanism of Human AMSH-LP Domain Deubiquitinating Enzymes.

Deubiquitinating enzymes (DUBs) catalyze the cleavage of the isopeptide bond in polyubiquitin chains to control and regulate the deubiquitination process in all known eukaryotic cells. The human AMSH-LP DUB domain specifically cleaves the isopeptide bonds in the Lys63-linked polyubiquitin chains. In this article, the catalytic mechanism of AMSH-LP has been studied using a combined quantum mechanics and molecular mechanics method.

Effects of inoculation of commercial starter cultures on the quality and histamine accumulation in fermented sausages.

To meet the requirements of high-quality safe products, starter cultures are used to produce fermented sausages. The effects of 3 commercial starter cultures, namely SM-194, T-SPX, and SM-181, on histamine accumulation and quality parameters including microbial quality, pH, water activity, and total volatile base nitrogen, as well as the color and texture properties, were evaluated during the fermentation and ripening of fermented sausages. Although initial counts of Escherichia coli, Enterobacteriaceae, and Pseudomonas were similar in the 4 batches, the growth of these microorganisms was significantly inhibited (P < 0.

A QM/MM study of the reaction mechanism of (R)-hydroxynitrile lyases from Arabidopsis thaliana (AtHNL).

Hydroxynitrile lyases (HNLs) catalyze the conversion of chiral cyanohydrins to hydrocyanic acid (HCN) and aldehyde or ketone. Hydroxynitrile lyase from Arabidopsis thaliana (AtHNL) is the first R-selective HNL enzyme containing an α/β-hydrolases fold. In this article, the catalytic mechanism of AtHNL was theoretically studied by using QM/MM approach based on the recently obtained crystal structure in 2012.

H(+) -ATPase-defective variants of Lactobacillus delbrueckii subsp. bulgaricus contribute to inhibition of postacidification of yogurt during chilled storage.

Unlabelled: Continued acid production by Lactobacillus delbrueckii subsp. bulgaricus during the chilled storage of yogurt is the major cause of postacidification, resulting in a short shelf life. Two H(+) -ATPase defective variants of L.