Abstract: This study aimed to optimize the extraction of polyphenols from Titeban wild Polygonatum cirrhifolium using ethanol as the extraction solvent. Towards this goal, one-factor-at-a-time method and orthogonal array design were employed to analyze the effects of extraction temperature, solid to liquid ratio, ethanol concentration, and extraction time on extraction efficiency. Furthermore, the antioxidant activities of polyphenol extracts were assessed by 1,1-diphenyl-2-picrylhydrazyl (DPPH), superoxide anion and hydroxyl free radical scavenging assays. The results showed the maximum extraction efficiency of polyphenols was achieved after 2.5 h extraction using 70% ethanol as the extraction solvent at a solid to solvent ratio of 1:25 (g/mL) at 70 ℃. The polyphenol extracts from P. cirrhifolium obtained under the optimized conditions had strong free radical scavenging capacities in comparison with VC, thus being a potential source of natural antioxidants.

Key words: Polygonatum cirrhifolium, polyphenols, extraction, antioxidant activity