Metagenomics unveils the roles of microbes in the metabolic network of purine formation during Huangjiu fermentation.

Purine is a major factor contributing to the development of hyperuricemia and gout, and it is found in large quantities in Huangjiu as free bases. Purine production in Huangjiu is strongly associated with microbial metabolism. However, to the best of our knowledge the microorganisms responsible for and the mechanisms of purine formation during Huangjiu fermentation are yet to be evaluated.

Construction of a synthetic microbial community and its application in salt-reduced soy sauce fermentation.

High salt conditions negatively affect the fermentation efficiency of soy sauce and human health. This study aimed to construct a synthetic microbial community based on dominant functional microorganisms for salt-reduced soy sauce fermentation by investigating the succession and function of the microbial community during factory soy sauce fermentation. The findings revealed that the interplay between salinity and microorganisms influenced the dynamic changes of microbial communities.

Exploring the Impact of Different Strains on the Flavor Profile of Greengage Alcoholic Beverage Using GC-E-Nose, HS-GC-IMS, and HS-SPME-GC-MS.

Greengage alcoholic beverage (GAB) is gaining popularity for its distinctive fruity aroma and nutritional benefits. The strain applied for fermentation significantly influences the metabolic production of aroma compounds, making the selection of strains to be critical for enhancing the unique flavor profile of the GAB in commercial production. In this study, the effects of two common commercial strains (SY, EC-1118) and two laboratory-derived strains (ET008-c54, NM-8) on the flavor profile of the GAB were investigated.

Glutathione metabolism contributes to citric acid tolerance and antioxidant capacity in Acetobacter tropicalis.

Acetobacter is one of the main species producing fruit vinegar and its tolerance mechanism to citric acid has not been fully studied. This limits fruit vinegar production from high-citric-acid fruits, which are excellent materials for fruit vinegar production. This study analyzed the metabolic differences between two strains of A.

Potential nutritional and functional matters in yeast culture prepared by soybean meal fermentation.

Background: Yeast culture (YC) is a product fermented on a specific medium, which is a type of postbiotic of anaerobic solid-state fermentation. Although YC has positive effects on the animal growth and health, it contains a variety of beneficial metabolites as dark matter, which have not been quantified. In the present study, liquid chromatography-tandem mass spectrometry is employed to identify the unknown metabolites.

Correlation between the bacterial community succession and purine compound changes during Huangjiu fermentation.

Purine is mainly culprit of hyperuricemia (HUA) and gout, which is widely present in Huangjiu in the form of free bases. Bacterial succession plays an important role in quality control in Huangjiu. The correlation between the purine compound content and the bacterial communities during the fermentation process has not yet been evaluated.

Enhancing citric acid tolerance of Acetobacter tropicalis using chemical and physical mutagenesis and adaptive evolution to improve the quality of lemon fruit vinegar.

The high concentration of citric acid in lemons limits the production of lemon fruit vinegar because it inhibits the metabolism of acetic acid bacteria and reduces the utilization of raw materials. This study aimed to enhance the citric acid tolerance of Acetobacter tropicalis by using complex mutagenesis and adaptive laboratory evolution (ALE) and improving the quality of lemon fruit vinegar. After mutagenesis and ALE, A.

Inhibition mechanism of fusarium graminearum growth by g-CN homojunction and its application in barley malting.

The increase of deoxynivalenol (DON) caused by Fusarium graminearum (F. graminearum) during the malting process is a serious safety problem. In our work, the inhibition mechanism of F.

The antifungal substance from Bacillus velezensis B-3 improved the malt quality against premature yeast flocculation induced by Fusarium graminearum infection.

Malt produced from barley contaminated with Fusarium graminearum can cause premature yeast flocculation (PYF) in beer fermentation, which ultimately affects the production efficiency and flavor quality of beer. In this study, a strain of Bacillus velezensis B-3 that was isolated from soil displayed strong antifungal activity against F. graminearum.

Evaluation of the differences between low-salt solid-state fermented soy sauce and high-salt diluted-state fermented soy sauce in China: from taste-active compounds and aroma-active compounds to sensory characteristics.

Background: The present study aimed to determine the components related to sensory properties in soy sauce and to characterize the differences between low-salt solid-state fermented soy sauce (LSFSS) and high-salt diluted-state fermented soy sauce (HDFSS). The taste and aroma active components of 18 commercially available soy sauces (eight types of LSFSS and 10 types of HDFSS) were characterized. The relationship between these compounds, soy sauce samples, and sensory properties was modeled by partial least squares regression.

Screening and application of purine degrading Limosilactobacillus fermentum LF-1 from Huangjiu fermentation broth.

Background: As the important building blocks of nucleic acids, purines are alkaloids and responsible for hyperuricemia and gout. The purine content in Huangjiu is higher, and mainly exists in the form of free bases, which is easier to be absorbed by human body. However, the currently available reports on purine in Huangjiu mainly focus on detection methods and content survey.

Evaluation of the antioxidant characteristics of craft beer with green tea.

The addition of green tea as antioxidants to beer can improve the beer's flavor stability by protecting against staling during storage. To analyze the effect of different green teas on the flavor stability of beer, we developed an approach to rapidly evaluate their antioxidant activity. Ten types of craft beer were produced by adding different kinds of green tea during brewing, and their antioxidant activity and phenolic profiles were evaluated.

Inhibition of Fusarium graminearum growth and deoxynivalenol accumulation in barley malt by protonated g-CN/oxygen-doped g-CN homojunction.

Barley malt, the main raw material for beer production, is at risk of Fusarium graminearum (F. graminearum) infection, leading to the possible production of large amounts of deoxynivalenol (DON) in malt. DON in malt can migrate into the final beer product, posing a food safety risk to consumers.

A highly-sensitive sensor based on carbon nanohorns@reduced graphene oxide coated by gold platinum core-shell nanoparticles for electrochemical detection of carbendazim in fruit and vegetable juice.

Carbendazim (CBZ) is beneficial to fruit and vegetable cultivation, but its residue will cause fruit and vegetable juice pollution. In this work, an electrochemical sensor based on carbon nanohorns@reduced graphene oxide coated by gold platinum core-shell nanoparticles (Au@Pt/CNHs@RGO/GCE) was prepared for CBZ detection. The results showed that the assembly of CNHs and RGO assisted by ultrasound improved the electron transfer ability and electrochemical active surface area of CNHs@RGO.

Highly sensitive electrochemical detection of carbendazim residues in water by synergistic enhancement of nitrogen-doped carbon nanohorns and polyethyleneimine modified carbon nanotubes.

Carbendazim (CBZ) can protect crops from pathogens, but it is also easy to cause pesticide residues, threatening human health. In our work, an electrochemical sensor based on nitrogen-doped carbon nanohorns (N-CNHs) and polyethyleneimine-modified carbon nanotubes (PEI-CNTs) was developed for the detection of CBZ content in water. The results showed that N-doping provided the CN bonds for CNHs and improved the electrochemical reaction performance of N-CNHs surface.

Enhancement Effect of Chitosan Coating on Inhibition of Deoxynivalenol Accumulation by Essential Oil Emulsion during Malting.

The purpose of this work was to study the enhancement effect of chitosan coating on inhibition of deoxynivalenol (DON) accumulation by essential oil emulsion during malting. Firstly, the primary emulsion suitable for malting process was screened and the improvement effect of chitosan coating on the properties of primary emulsion was studied. On this basis, chitosan-based essential oil emulsion was applied to malting processing.

Key Compounds and Metabolic Pathway Responsible for the Browning in Dangshan Pear ( spp.) Wine.

Based on hydrophilic interaction liquid chromatography (HILIC) liquid chromatography-mass spectrometry (LC-MS), untargeted differential metabolomics analysis was performed on the pear wine samples before and after browning to determine the key compounds that affect the browning of Dangshan pear wine. A total of 196 significantly differential metabolites were found, 22 of which might be related to the browning of Dangshan pear wine. d-(+)-glucose, l-phenylalanine, l-norleucine, methionine, d-(+)-proline, aloin, and rutin were the key differential metabolites in pear wine before and after browning.

Isolation and identification of the bitter compound from Huangjiu.

The strategy of taste-guided assisted by solvent extraction, solid-phase extraction and semipreparative HPLC were applied to isolate the main nonvolatile bitter components from mechanized Huangjiu. The potential fraction was identified by amino acid analysis and ultra-performance liquid chromatography-quadrupole-time-of-flight-MS/MS. Bitter pyroglutamate peptide Pyr-LFNPSTNPWHSP (PGP) was successfully identified from Huangjiu for the first time.

Profiling the key metabolites produced during the modern brewing process of Chinese rice wine.

The study quantitatively profiled 83 low-molecular-weight metabolites in the categories of alcohols, aldehydes, amino acids, esters, fatty acids, organic acids, and reducing sugars produced during the advanced brewing process of Chinese rice wine, using multiply chromatography and mass spectrum. In the primary fermentation, vigorous metabolisms were demonstrated by the production of ethanol at the level of 14% by volume, and the consumption of reducing sugars from the maximum level of 100 g/L to 20 g/L. Meantime, more than 70% of the contents of organic acids, fatty acids, higher alcohols, and aldehydes were formed.

Development of a novel multi-strain wheat Qu with high enzyme activities for Huangjiu fermentation.

Background: Wheat Qu has long been used as a fermentation starter to produce Huangjiu. Wheat Qu quality depends on its microbial community structure and the hydrolytic enzymes generated by the micro-organisms.

Results: Strain YF1 and YF2 were successfully screened as they exhibited high acidic protease (231.

Objective measures of greengage wine quality: From taste-active compound and aroma-active compound to sensory profiles.

This study is sought to identify the components in greengage wine that predict the sensory properties. Taste-active compounds and aroma-active compounds of 20 commercially available greengage wines from different regions were characterized. The relationship between these compounds, wine samples and sensory attributes was modeled by partial least squares regression.

Uncovering mechanisms of greengage wine fermentation against acidic stress via genomic, transcriptomic, and metabolic analyses of Saccharomyces cerevisiae.

Acid stress is one of the most common adverse conditions during fermentation of fruit wines, and the acid tolerance of yeasts is, therefore, critical for fruit wine production. However, the biological mechanism underlying the acquired tolerance of yeasts against acid stress is poorly understood. We have previously obtained an evolved Saccharomyces cerevisiae strain ET008-c54 with increased tolerance against acid stress, and potentially, it serves as a promising yeast strain for greengage wine fermentation.

Metabolic engineering of Saccharomyces cerevisiae using the CRISPR/Cas9 system to minimize ethyl carbamate accumulation during Chinese rice wine fermentation.

Ethyl carbamate (EC) is a potential carcinogen to humans that is mainly produced through the spontaneous reaction between urea and ethanol during Chinese rice wine brewing. We metabolically engineered a strain by over-expressing the DUR3 gene in a previously modified strain using an improved CRISPR/Cas9 system to further decrease the EC level. Homologous recombination of the DUR3 over-expression cassette was performed at the HO locus by individual transformation of the constructed plasmid CRISPR-DUR3-gBlock-HO, generating the engineered strain N85-c.

A multiple-step strategy for screening Saccharomyces cerevisiae strains with improved acid tolerance and aroma profiles.

Acid tolerance and aroma profile are crucial factors for wine production in Saccharomyces cerevisiae. However, most wine yeasts to date fail to endure low-pH environments, therefore resulting in problems such as lengthened fermentation and poor flavor during acidic fruit wine production. In the present study, we established a multiple-step screening strategy, which was composed of atmospheric and room temperature plasma (ARTP), high-throughput screening (HTS), and laboratory adaptive evolution (ALE), to screen yeast strains for potential wine-producing with enhanced performances during low pH conditions.

Levan from Bacillus amyloliquefaciens JN4 acts as a prebiotic for enhancing the intestinal adhesion capacity of Lactobacillus reuteri JN101.

Improving intrinsic adhesion performance of the known probiotics facilitates their residence and colonization, and therefore exerts more beneficial effects on the human or animal host. In this study, through adaptive culture with levan, Lactobacillus reuteri JN101 achieved the same biomass and exhibited 2.6 times higher adhesion capacity to HT-29 cells than those grown with glucose.