Chemical Composition and Antimicrobial Activity of Essential Oils from the Leaves and Stems of Tinomiscium petiolare Hook.f. & Thomson from Vietnam

Essential oils from the leaves and stems of Tinomiscium petiolare Hook.f. & Thomson were obtained by hydrodistillation and the chemical components were determined by gas chromatography (GC) and gas chromatography coupled with mass spectrometry (GC/MS). Also, the microdilution broth assay was used to test the antimicrobial activity of essential oils. The respective yields of the T. petiolare leaf and stem essential oils were 0.06 % and 0.04 % (v/w), calculated on a dry weight basis. The major components (percentages, respectively) identified from the leaf and stem essential oils of T. petiolare were relatively similar, comprising of β-bisabolene (11.43 % and 13.80 %), trans-α-bergamotene (6.52 % and 6.61 %), geranyl acetate (6.12 % and 5.77 %), (E)-caryophyllene (5.04 % and 4.73 %), δ-cadinene (4.10 % and 5.27 %), (E,E)-α-farnesene (4.54 % and 4.65 %) and α-zingiberene (3.85 % and 4.50 %). The antimicrobial activity test indicated that T. petiolare stem essential oil displayed moderate activity against Staphylococcus aureus ATCC 6538 with Minimum inhibitory concentration (MIC) value of 200 μg/mL, while both essential oils inhibited the growth of Pseudomonas aeruginosa ATCC 9027 with MIC value of 200 μg/mL. The chemical components and antimicrobial activity of the T. petiolare leaf and stem oils are reported for the first time.