Analysis of the Volatile Constituents of AsianHypericumL. (Clusiaceae, Hyperidoideae) Species

Of the 57 species of the economically important genus Hypericum (St. John's Wort; Clusiaceae) occurring in China, only a small percentage have been previously phytochemically investigated. As part of our continuing research on the phytochemistry of Hypericum, the chemical compositions of volatiles isolated from 12 Chinese species were determined. Volatile constituents were isolated by microdistillation of dried and ground aerial material from flowering plants and subsequently analyzed by GC/MS. The major component(s) were identified as follows: ar-curcumene (12.6%) and β-selinene (16.3%) in H. acmosepalum; γ-muurolene (11.3%), β-selinene (16.3%) and caryophyllene oxide (18.7%) in H. beanii; α-terpineol (11.5%) and P-pinene (29.2%) in H. calycinum; cis-eudesma-6,11-diene (11.4%) in H. choisyanum; a-pinene (10.4%) and caryophyllene oxide (12.7%) in H. forrestii; cis-β-guiaene (10.7%) and γ-muurolene (12.4%) in H. kouytchense; β-selinene (11.4%) and eudesmadienone (10.8%) in H. lancasteri; cuparene (24.8%) and γ-muurolene (16.8%) in H. leschenaultii; tricosane (13.3%) and myrcene (10.4%) in H. monogynum; β-selinene (14.7%) in H. patulum; β-selinene (18.5%) in H. pseudohenryi; and γ-muurolene (10.7%) and δ-cadinene (10.2%) in H. X moserianum.