Exploring the roles of microorganisms and metabolites in the fermentation of sea bass (Lateolabrax japonicas) based on high-throughput sequencing and untargeted metabolomics

Microbial diversity is essential for determining the characteristic quality of fermented sea bass products. However, how microbial community succession affects metabolite profiles during fermentation remains poorly understood. In this study, using 16S and 18S rRNA gene sequencing, eight bacterial and four fungal microorganisms were identified as the dominant genera during the fermentation of sea bass. Ultra-high performance liquid chromatography with triple time-of-flight mass spectrometry was used to identify the metabolite profiles and a total of 54 metabolites were identified. Our results showed that the metabolic activities of Streptococcus, Macrococcus, Psychrobacter, Trichosporon, and Aspergillus were correlated with the production of amino acids, peptides, amines, lipids, and organic acids. Metabolic pathway analysis showed that these metabolites are related to various types of amino acid metabolism. We hope that our study will provide a new theoretical basis and research perspective that may improve the sea bass fermentation process.