Antimicrobial Activity and Chemical Constituents of Essential Oils from the Leaf and Wood of Taxus chinensis (Rehder & E.H. Wilson) Rehder (Taxaceae) from Vietnam

Abstract

This paper report the volatile compounds identified in the leaf and wood essential oil hyrdrodistilled from Taxus chinensis (Rehder & E.H. Wilson) Rehder (Taxaceae) from Vietnam. The chemical constituents of the oil were analysed by gas chromatography (GC) and gas chromatography coupled with mass spectrometry (GC/MS). The yields of the yellow oils were 0.15 % and 0.11 % (v/w) respectively, calculated on a dry weight basis. The main constituents of the leaf oil were monoterpenes represented by α-pinene (24.2 %), sabinene (19.5 %), α-terpinyl acetate (12.8 %) and 1,8-cineole (11.7 %). However, α-pinene (20.0 %), photosantalol (10.2 %), caryophyllene oxide (8.9 %), spathulenol (7.6 %) and guaiol (6.8 %) were the representative compounds of the wood oil. The essential oils displayed antimicrobial activity against Enterococcus faecalis ATCC 299212 with MIC values of 16.0 and 64.0 μg/mL, and IC50 of 3.98 and 20.33 μg/mL, respectively. However, only the leaf oil inhibited the growth of Bacillus cereus ATCC 14579 with MIC and IC50 values of 64.0 and 19.78 μg/mL, while showing stronger action towards Candidan albicans ATCC 10231 with MIC of 128.0 μg/mL. Moreover, the wood oil exhibited stronger antimicrobial activity against Staphylococcus aureus ATCC 25923 (MIC 128.0 μg/mL, IC50 56.78 μg/mL) and displayed moderate antimicrobial action against Escherichia coli ATCC25922 with MIC and IC50 values of 256.0 and 87.78 μg/mL respectively.