Effects of probiotic fermentation on the enhancement of biological and pharmacological activities of Codonopsis lanceolata extracted by high pressure treatment

This study was designed to evaluate the enhancement of antioxidant, antimicrobial, enzymatic, cytotoxic, and cognitive activities of Codonopsis lanceolata extracted by high pressure treatment followed by probiotic fermentation. Dried C. lanceolata samples were subjected to 400 MPa for 20 min and then fermented with Bifidobacterium longum B6 (HPE-BLF) and Lactobacillus rhamnosus (HPE-LRF) at 37°C for 7 days. Compared to conventional extraction (CE-NF, 6.69 mg GAE/g), the phenol amounts of HPE-BLF and HPE-LRF were significantly increased to more than 8 mg GAE/g, while the lowest flavonoid contents were observed for HPE-BLF (0.44 mg RE/mL) and HPE-LRF (0.45 mg RE/mL) (p < 0.05). Cinnamic acid was the most abundant phenolic acid in the fermented C. lanceolata. The highest DPPH scavenging activities were observed for HPE-BLF and HPE-LRF, with minimum EC50 values of 1.26 and 1.18 mg/mL, respectively. The HPE-BLF and HPE-LRF samples exhibited the most noticeable antimicrobial activities against Staphylococcus aureus, Listeria monocytogenes, Salmonella Typhimurium, and Shigella boydii (MICs < 15 mg/mL). The fermented C. lanceolata samples effectively inhibited α-glucosidase and tyrosinase activities and potentially improved a scopolamine-induced memory deficit in mice. The application of a fermentation process can effectively improve the biological and pharmacological activities of high-pressure-extracted C. lanceolata by increasing the extraction efficacy and inducing probiotic conversion. The results suggest that the combined treatment of HPE and a fermentation process could be used as alternative extraction method over CE.