Lidong Guo

This study aimed to isolate acid-tolerant lactic acid bacteria from Suancai, a traditional Chinese fermented vegetable, and evaluate their potential and safety as candidate probiotics. Fifteen dominant lactic acid bacteria strains were isolated from spontaneously fermented Suancai, and four isolates were selected based on their tolerance to acid and bile, as well as their autoaggregation, coaggregation, cell surface hydrophobicity, and adhesion capabilities. Based on 16S rRNA and pheS gene sequence analyses, the four strains were identified as Lactiplantibacillus plantarum (strain S5) and Levilactobacillus brevis (strains S1, H1, and H2). These strains were further evaluated for multiple in vitro probiotic properties. All four exhibited cholesterol removal capacity, DPPH and hydroxyl radical scavenging activity, gamma-aminobutyric acid production, and nitrite degradation ability. α-Glucosidase inhibitory activity was observed in three strains, with the exception of Levilactobacillus brevis S1. Additionally, all strains displayed antimicrobial activity against Escherichia coli, Staphylococcus aureus, and Salmonella paratyphi B. Safety assessment revealed that the strains were sensitive to ampicillin, erythromycin, and penicillin, resistant to gentamycin, and negative for indole production and hemolytic activity. In conclusion, the four selected strains demonstrated favorable probiotic characteristics and safety profile, supporting their potential as candidate probiotics for functional food application.

Panax ginseng is a precious Chinese medicinal plant with a long growth cycle and high medicinal value. Therefore, it is of great significance to explore effective ways to increase its yield and main active substance content to reduce the cost of ginseng, which is widely used in food and clinical applications. Here, we review the key roles of microorganisms in the biological control of ginseng diseases, enhancement of ginseng yield, biotransformation of ginsenosides, and augmentation of ginsenoside bioactivity. The application of microorganisms in P. ginseng faces multiple challenges, including the need for further exploration of efficient microbial strain resources used in the cultivation of ginseng and biotransformation of ginsenosides, lack of microbial application in large-scale field cultivation of ginseng, and unclear mechanism of microbial transformation of ginsenosides. This review provides a deeper understanding of the applications of microorganisms in P. ginseng.