Metabolite Profiling and Microbial Community of Traditional Meju (Fermented Soybean Paste) Show Primary and Secondary Metabolite Differences Correlated with Antioxidant Activities.

Metabolite Profiling and Microbial Community of Traditional Meju (Fermented Soybean Paste) Show Primary and Secondary Metabolite Differences Correlated with Antioxidant Activities.

J Microbiol Biotechnol. 2020 Sep 02;:

Authors: Song DH, Chun BH, Lee S, Reddy CK, Jeon CO, Lee CH

Abstract
Meju, a fermented soybean paste, is used as a starter for the preparation of different Korean traditional soybean foods. The traditional meju facilitate fermentation in the presence of the natural microbiome. In this study, we performed Illumina-MiSeq paired-end sequencing for microbial communities and mass spectrometry analysis for metabolite profiling to investigate the differences between 11 traditional meju, produced in different regions of Korea. Even though the bacterial and fungal communities showed remarkable variety, major genera, such as Bacillus, Enterococcus, Variovorax, Pediococcus, Weissella, and Aspergillus, were detected in all meju. The metabolite profile patterns of the 11 samples were clustered into two main groups: group I (M1-5) and group II (M6-11). The metabolite analysis indicated a relatively higher amino acid content in group I, while group II exhibited higher isoflavone, soyasaponin, and lysophospholipid contents. The bioactivity analysis proved that the ABTS (2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid)) radical-scavenging activity was higher in group II and the FRAP (ferric reducing antioxidant power) activity was higher in group I. The correlation analysis revealed that the ABTS activity was isoflavonoid, lipid, and soyasaponin-related, whereas the FRAP activity was amino acid- and flavonoid-related. In conclusion, these results suggest that the antioxidant activity of meju are critically influenced by the microbiome and metabolite dynamics.

PMID: 32876067 [PubMed – as supplied by publisher]

Source: Industry