ABSTRACT
OBJECTIVE:To optimize the extraction technology of caffeic acid in Laggera alata,and establish a method for its content determination. METHODS:The caffeic acid in L. alata was extracted by reflux extraction. Using extraction content as inves-tigation index,orthogonal test was used to investigate the effects of ethanol volume fraction,material-liquid ratio and extraction time on caffeic acid,and the extraction technology conditions were optimized. HPLC was adopted to determine the content of caffe-ic acid in 10 batches of L. alata from different areas,using caffeic acid as reference substance,at wavelength of 320 nm. RE-SULTS:The optimized extraction technology conditions were as follows as ethanol volume fraction of 10%,material-liquid ratio of 1 : 40 and extraction time of 3 h. Under the condition,verification test for caffeic acid was carried out,and the average content of caffeic acid in L. alata was 0.5211 mg/g(RSD=1.18%,n=3). The content of caffeic acid in 10 batches of L. alata from dif-ferent areas ranged in 0.3752-0.7766 mg/g,and the content showed great differences. CONCLUSIONS:The content of caffeic ac-id in L. alata is related to area and harvest season. The caffeic acid extration by optimized technology shows good reproducibility;and the established method for content determination is stable and feasible.