Microbial Composition Dynamics Research Articles

Microbial Composition Dynamics in Peloids Used for Spa Procedures in Lithuania: Pilot Study.

Despite peloids' acknowledged therapeutic and cosmetic potential, there remains a limited understanding of their microbial diversity and dynamics, especially concerning beneficial and non-beneficial microorganisms under different heating conditions. Our study employs both cultivation and metagenomic methods to assess the microbiota of peloids, focusing on lake sapropel and peat under heating conditions recommended for external application and safety assurance. By applying microbial indicators specified in national regulatory documents, we found that all peloids reached thresholds for sulphite-reducing clostridia and colony-forming units. Each peloid exhibited a distinctive bacterial composition based on metagenomic analysis, and temperature-induced changes were observed in microbial diversity. We identified beneficial bacteria potentially contributing to the therapeutic properties of peloids. However, the same peloids indicated the presence of bacteria of human faecal origin, with a notably higher abundance of Escherichia coli, pointing to a potential source of contamination. Unfortunately, it remains unclear at which stage this contamination entered the peloids. The findings underscore the importance of monitoring and controlling microbial aspects in peloid applications, emphasising the need for measures to prevent and address contamination during their preparation and application processes.

Microbial diversity and flavor of Chinese rice wine (Huangjiu): an overview of current research and future prospects

Chinese rice wine (Huangjiu), a typical representative of traditional fermented foods in China, is distinguished for its unique flavor. Microorganisms play the most important role in the formation of the unique flavor of Huangjiu. The complex flavor components in Huangjiu are closely related to the metabolism of various microorganisms during the traditional brewing. Therefore, understanding the influence of microbiota on the formation of flavor components in Huangjiu is conducive to the production of Huangjiu with high-quality flavor. In recent years, many scholars have conducted a large number of studies on the microbial community and flavor metabolites during the traditional brewing process of Huangjiu, with the help of high-throughput sequencing (HTS) and mass spectrometry-based metabolomics. This review mainly summarized the current study progress of the microbial diversity of fermentation starters (Qu) and brewing process of Huangjiu, and explored the potential relationship between the microbial community and the characteristic flavor formation of Huangjiu. Through the comparative analysis of literatures, we found that Huangjiu has strong regional characteristics due to the differences in raw materials, Qu and traditional brewing techniques. Dynamics of microbial composition during the traditional brewing of Huangjiu in different regions of China are quite different, making Huangjiu in each region have their own flavor characteristics. Therefore, revealing the relationship between brewing microorganisms and flavor characteristics of Huangjiu is helpful to the directional regulation of flavor quality. According to the current research status, it is proposed that in the future, emerging technologies such as multi-omics, artificial intelligence, and machine learning should be applied to further improve the accuracy of the analysis of microbial flora and flavor components in Huangjiu, so as to accurately reveal the relationship between the microbial community and the formation of characteristic flavor of Huangjiu. Afterwards, high-throughput screening of excellent functional strains from the traditional brewing system should be applied to the industrial production of Huangjiu, so as to improve the overall flavor quality and commercial value.