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Composition and Two Activities of the Leaf Essential Oil of Litsea acuminata (Blume) Kurata from Taiwan

Yu-Chang Su and Chen-Lung Ho

Department of Forestry, National Chung Hsing University, 250 Kuo Kuang Rd., Taichung, Taiwan 402

Division of Wood Cellulose, Taiwan Forestry Research Institute. 53, Nanhai Rd., Taipei, Taiwan 100

Abstract: This study investigated the chemical composition, and antimicrobial and anti -wood-decay fungal activities of the essential oil isolated from the leaf of Litsea acuminata (Blume) Kurata from Taiwan. The essential oil from the fresh leaves of L.acuminata was isolated using hydrodistillation in a Clevenger-type apparatus, and characterized by GC–FID and GC–MS. A total of 48 compounds were identified, representing 100% of the oil. The main components identified were b -caryophyllene (13.0%), t -cadinol (11.1%), a -cadinol (8.6%), α-humulene (7.5%), a -pinene (7.0%), globulol (6.6%), and b -eudesmol (6.1%) . The antimicrobial activity of the oil was tested by the disc diffusion method and micro-broth dilution method against ten microbial species, respectively. The oil exhibited strong growth suppression against Gram-positive bacteria and yeast with inhibition zones of 4 5~ 50 mm to MIC values of 31.25~62.5 μg / mL, respectively. The anti-wood-decay fungal activity of the oil was also evaluated. Results showed that the oil demonstrated excellent activity against four wood-decay-fungi species. For the antimicrobial and anti-wood-decay fungal activities of the oil, the active source compounds were determined to be t -cadinol, a -cadinol, and b -eudesmol.

Keywords: Litsea acuminate ; Lauraceae ; essential oil ; antimicrobial activit y; anti -wood-decay fungal activit y; t -cadinol; a -cadinol .