In this study, we successfully obtained a novel source protein glutaminase PG5 with specific activity of 10.4 U/mg, good tolerance and broad substrate profile through big data retrieval. Structural analysis and site-directed mutagenesis revealed that the catalytic pocket of Mature-PG5 contained a large number of aromatic amino acids and hydrophobic amino acids, and that Ser72 greatly affects the properties of the catalytic pocket and the affinity of PG5 for the substrate.
View Article and Find Full Text PDFTo improve the flavor profile and sensory quality of baijiu, the utilization of bioaugmented fermentation inoculated with functional microbiota normally serves as an effective method for directional regulation during the baijiu fermentation process. In this study, a systematic analysis of the succession patterns and volatile flavor compound profiles of microbial communities was carried out by high-throughput sequencing and solid-phase microextraction gas chromatography-mass spectrometry, respectively. The results demonstrated that the Saccharomyces cerevisiae YS222-related bioaugmentation clearly altered the microbial composition, particularly the assembly of bacteria, and promoted the quantity of the most volatile flavoring compounds, including alcohols, esters, and pyrazines.
View Article and Find Full Text PDFThe fermentation process of traditional shrimp paste is closely associated with the production of flavor substances, but the formation mechanism of key aroma components is still unclear. In this study, a comprehensively flavor profile analysis of traditional fermented shrimp paste was carried out by E-nose and SPME-GC-MS. A total of 17 key volatile aroma components with OAV > 1 contributed greatly to the overall flavor formation of shrimp paste.
View Article and Find Full Text PDFMicrobial contamination is one of the most common food safety issues that lead to food spoilage and foodborne illness, which readily affects the health of the masses as well as gives rise to huge economic losses. In this study, was used as a source of antimicrobial agent that was then analyzed by untargeted metabolomics for its antibacterial mechanism against . The results indicated that the skin mucus extract of had great inhibitory action on the growth of , and the morphology of cells treated with the skin mucus extract exhibited severe morphological damage under scanning electron microscopy.
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