Fermentation of Polygonatum cyrtonema with lactic acid bacteria to improve its flavor, antioxidant, and hypouricemic potential

This study aimed to investigate the transformation of Polygonatum cyrtonema Hua (PCH) by lactic acid bacteria (LAB), including Lactobacillus plantarum (P-5, Z-2, and 28–1) and Lactobacillus pentosus P-7. LAB-fermented PCH (FPCH) altered sugar and acid profiles, along with increasing total phenolics, flavonoids, and saponins. FPCH developed a more complex and pleasant aroma profile, marked by increased key flavor compounds such as 2-undecanone and β-damascenone; meanwhile, astringency and green/herbal off-odors, represented by epigallocatechin (EGCG), were reduced. LAB fermentation increased naringin and 4-hydroxybenzoic acid contents, enhancing antioxidant capacity. Notably, FPCH fermented by L. plantarum P-5 (P-5-FPCH) protected PC12 cells against oxidative stress and further alleviated uric acid-induced oxidative injury in HK-2 renal tubular epithelial cells. In hyperuricemic mice, P-5-FPCH reduced serum uric acid levels and alleviated renal injury, likely by increasing caffeic and cinnamic acids. Transcriptome analysis of LAB revealed the above-mentioned related genes ( sacA, pyk, and adh ). Overall, LAB fermentation offers a safe and promising bioprocessing strategy to enhance the quality and bioavailability of PCH.