紫外分光光度法测定番石榴叶总三萜含量

Determination of total triterpenes from Psidium guajava L. by ultraviolet Spectrophotometry

目的：建立一种番石榴叶药材中总三萜含量测定的方法，并考察10批番石榴叶药材中总三萜含量。方法以熊果酸为对照品，香草醛-冰醋酸-高氯酸为显色体系，采用紫外分光光度法在最大吸收波长为548nm处测定番石榴叶药材总三萜含量。结果熊果酸在8.13～28.44μg · mL^ -1范围内线性关系良好，总三萜平均回收率为99.43％，RSD为2.30％。结论该方法操作简便、快速、准确、稳定可靠，可作为番石榴叶药材总三萜含量测定的方法。

OBJECTIVE To establish a method for the quality control of Psidium guajava L.and investigate the quality of 10 batches of Psidium guajava L.collected from different places.METHODS Ursolic acid and vanillin-acetic acid-perchloric acid system were employed as reference substance and chromogenic reagent ,respectively,the total triterpenes of Psidium guajava L.was measured by UV spectrophotometry at the 548 nm.RESULTS The linear relationship of ursolic acid was in the range of 8.13~28.44μg· mL^-1.The average recovery was 99.43%（ RSD=2.30%）.CONCLUSION This method is simple ,quick,accurated,stable and reliable,and it could be used to de-termine the total triterpenes of Psidium guajava L.