CHEMICAL COMPOSITIONS, ANTIBACTERIAL AND ANTIOXIDANT ACTIVITITES OF ESSENTIAL OIL FROM (PLECTRANTHUS AMBOINICUS (LOUR.) SPRENG) COLLECTED IN DAK LAK

Abstract

The fresh leaves of (Plectranthus amboinicus (Lour.) Spreng) were collected at Buon Ma Thuot city, Dak Lak province and essential oil, extracted by distillation,
accounted for 0.18 - 0.3% by weight of the fresh leaves. Chemical compositions of Hung chanh essential oil have been examined by GC-MS. Thirty-four compounds
were identified, among those the main compounds are: Carvacrol (52.32%), γ-Terpinene (18.92%), p-Cymene (7.56%), Caryophyllene (5.6%), cis-α-Bergamotene
(2.86%), α-Humulene (2.68%) and Aromandendrene (1.78%). The essential oil was tested for the antibacterial activity on E. coli. The results showed that at the
concentration of 8.5mg/mL, the essential oil inhibited by about 87.35% on E. coli. The antioxidant capacity of the essential oil was also determined by DPPH method.
The highest antioxidant efficiency of the essential oil was 89.21% at concentration of 10µg/mL. The IC50 value of the essential oil was 4.13μg/mL, eight-times less than
that of ascobic acid (IC50 value of 34.99μg/mL). The research shows that essential oil of the leaves of Plectranthus amboinicus (Lour.) Spreng might be a natural
potential source of antibacterial and antioxidant agents.