To optimize the extraction process of total alkaloids from Corydalis yanhusuo and evaluate its analgesic and anti-inflammatory activities.Methods:Based on single-factor experiments,the ethanol concentration,liquid-to-material ratio,extraction temperature,and extraction time were selected as influencing factors.The dehydrocorydaline content,measured by high-performance liquid chromatography(HPLC),was used as the index to optimize the extraction process via an orthogonal L9(34) experiment.The analgesic activity of total alkaloids from C.yanhusuo was evaluated using the acetic acid writhing test and the hot plate method.The anti-inflammatory activity was assessed using the xylene-induced ear swelling test and the egg albumin-induced paw swelling test in mice.Results:The optimal extraction process for total alkaloids from C.yanhusuo was a 1:25 material-to-solvent ratio,with 80% ethanol,extracted at 50 ℃ for 3.5 h.The total alkaloids significantly reduced the number of writhing movements induced by acetic acid,increased the pain threshold in mice,and inhibited the ear swelling caused by xylene and paw swelling induced by egg albumin(P<0.01 or P<0.05).Conclusion:The ethanol reflux extraction method,optimized based on the dehydrocorydaline content measured by HPLC,is simple,feasible,stable,and reliable.Moreover,the total alkaloids from C.yanhusuo exhibit significant in vivo analgesic and anti-inflammatory activities.