Development of an HPLC method for quality control of Alpinia zerumbet

The Brazilian National Medicinal Plants and Herbal Medicines Programme provides for the distribution of herbal medicines in all local municipal, state and federal health services. Alpinia zerumbet (Pers.) B.L. Burtt & R.M.Sm. is traditionally employed to treat hypertension. The Herbal Medicines Formulary of the Brazilian Pharmacopoeia lists Alpinia zerumbet as a diuretic and for the treatment of mild hypertension. However no chromatographic method for quality control is described. Since flavonoids are involved in the pharmacological activity, a HPLC method has been developed for the analysis of Alpinia zerumbet aqueous extract, and Rutin was selected as reference for quantification. Using statistical experimental design the method was optimized as regards the amounts of acetonitrile, acidified water and methanol in the mobile phase composition using an RP-18 column. All analyses were performed with aqueous Alpinia zerumbet extracts. In five runs an optimal separation was approached. A linear regression of rutin was performed and with the optimized mobile phase composition it was possible to analyze the flavonoid glycosides present in the extract. Regression analysis indicated an adequate fit with a determination coefficient (R²) of 0.9999. Repeatability was also adequate with maximum relative standard deviation of 1.84%. The rutin content was calculated as 0.44% and the total amount of flavonoid glycosides, calculated by rutin regression, was estimated to be 4%. This developed procedure is important for the systematic quality control of the herbal drugs and their preparations in ensuring the degree of safety, efficacy and quality required by the National Health Programme.