As a continuing study on the evaluation of various Zingiberis Rhizoma and the chemical characterization of the processing, a quantitative method by high performance liquid chromatography (HPLC) for 6, 8, 10-gingerol (1, 2, 3), 6, 8-shogaol (4, 5), 6-dehydrogingerdione (6), and galanolactone (7) has been developed. By the use of this HPLC method, the contents of these compound in twenty kinds of Zingiberis Rhizoma [originating in China, Taiwan, Vietnam, and Japan (Shizuoka Prefecture)] and fresh ginger root cultivated in Shizuoka Prefecture were examined. It was found that Japanese Zingiberis Rhizoma and fresh ginger root contained 6-gingerol (1), 6-dehydrogingerdione (6), and galanolactone (7) as major constituents, whereas 7 was not detected in imported Zingiberis Rhizoma and 6 was detected in Vietnamese Zingiberis Rhizoma. Furthermore, the contents of 1 and 7 in fresh ginger root decreased remarkably during the processing procedure for Zingiberis Rhizoma. In addition, anti-ulcer sesquiterpene constituents in seven kinds of Zingiberis Rhizoma were analyzed by means of gas liquid chromatography (GLC).
