Fermentation interactions and lipid-lowering potential of Monascus purpureus fermented Ginseng

Monascus fermented Ginseng exhibits superior lipid-regulation activity compared to the raw materials, which undoubtedly related to fermentation-induced changes. This study aims to elucidate the interactions between Monascus purpureus (M. purpureus) and ginseng during fermentation and identify an effective ginseng fraction optimal for co-fermentation. Initially, the effective fractions extracted from ginseng—total polysaccharides, amino acids, and ginsenosides, were separately added to the basic medium to assess their impact on M. purpureus growth and metabolism. Meanwhile, ginsenoside transformation during fermentation was also investigated. The fermentation product derived from the selected ginseng fraction and M. purpureus was assessed for its lipid-lowering efficacy. The results indicated that total amino acids and total ginsenosides, except for total polysaccharides, facilitated the growth of M. purpureus and enhanced Monacolin K production. The expression levels of genes associated with M. purpureus metabolism exhibited significant alterations. The changes in various ginsenoside monomers revealed potential ginsenoside transformation pathways during the fermentation process. Additionally, Monascus purpureus fermented Ginsenosides exhibited lipid-lowering efficacy comparable to Monascus fermented Ginseng, potentially regulating the lipid metabolism via the Peroxisome proliferator-activated receptor and Sterol regulatory element-binding protein (PPAR/SREBP) signaling pathway. These insights not only elucidate the interaction mechanisms between M. purpureus and ginseng fractions during fermentation but also demonstrate the lipid-lowering potential of Monascus purpureus fermented Ginsenosides at both cellular and molecular levels, highlighting certain significance for the rational utilization of ginseng resources, revealing the key role of microorganisms in the fermentation process.