Physiological Activities of Fermented <i>Perilla frutescens</i> Leaves

This study examined the fermented Perilla frutescens var.japonica Hara (P.frutescens) leaves produced using Saccharomyces cerevisiae, Bacillus subtilis, Levilactobacillus brevis, Lacticaseibacillus casei, and Lactiplantibacillus plantarum.The groups fermented with S. cerevisiae and B. subtilis strains showed the highest total sugar content among all samples, and the groups fermented with S. cerevisiae strains showed the highest reducing sugar content among all samples.The Lc. casei group was the most effective in the total polyphenol and flavonoid contents, DPPH and ABTS radical scavenging activities, FRAP values, tyrosinase inhibition activity, and nitrite scavenging activity.This was attributed to the largest increase in the total polyphenol content, which can enhance the antioxidant, tyrosinase inhibitory, and nitrite scavenging activities.These results showed that the Lc.casei strain was the most suitable for improving the physiological activities of P. frutescens leaves, and fermented P. frutescens leaves produced with the Lc.casei strain are expected to be useful as natural ingredients for functional material.