Volatile constituents of the essential oils of two Polygonum species from Vietnam

Polygonum species grown in many places in Vietnam, esp. on the rice-field. It is used in the traditional medicine. After Pham Hoang Ho until now in Vietnam, 40 Polygonum species have been found. From the polygonum genus (Family Polygonaceae) the essential oils of 2 species are reported: Polygonum hydropiper (L.) and Polygonum sp. Using HRGC and GC/MS more than 30 components from Polygonum hydropiper (L.) were sepd. Among these 2 main compds. with MW = 216 (28.40%, 29.00%) and MW = 218 (27.63%, 27.78%) resp. were found in the stem and leaf oils. Other compds. with relative low concn. in the stem and leaf oils are a-humulene (7.06%, 7.14%), compd. with MW = 218 (4.62%, 4.51%), sesquiterpene alc. with MW = 220 (4.86%, 4.89%) and curcumene (2.5%). The main constituents in the essential oil of Polygonum sp. are a-humulene (16.75%), b-elemene (14.32%), and (Z)-b-farnesene (11.16%