Hsin-Chun Chen and Ming-Jen Sheu, Li-Yun Lin and Chung-May Wu*

Abstract: The composition of the essential oil obtained from the hydrodistillation of the leaves of Psidium guajava L. was analyzed by capillary GC and GC/MS. A total of 50 compounds were identified. The major constituents identified in the oil were: b-caryophyllene (27.7%), a-pinene (14.7%) and 1,8-cineole (12.4%).

Plant Name <i>Psidium guajava</i> L. (Myrtaceae). Source The fresh leaves of <i>Psidium guajava</i> L. were obtained from Chang-hua in the central of Taiwan. Plant Part The leaves (400 g) were prepared by blending guava leaves for 3 min with 2 L of deionized water in a blender and put into a 5 L round-bottom flask. Leaves were steam-distilled for 2 h to obtain the leaf essential oil (0.2%, the value is mean of three replications). Previous Work Guava (<i>Psidium guajava</i> L.) is native to Central America. It was distributed into tropical and subtropical areas by the early 17th century. In Taiwan, it’s grown commercially for its fruit and used as a traditional therapy for dysentery or diabetes for its leaf. Several reports have been published covering the volatile compounds of <i>Psidium</i> spp. leaf (2–11).