Composition and antioxidant capacity of the essential oil of leaves of Vitex megapotamica (Sprengel) Moldenke

Abstract

This study is designed to examine the chemical composition and antioxidant activity of the essential oil of Vitex megapotamica. Gas chromatography–mass spectrometry analysis resulted in the detection of 27 components, representing 92.36% of the total oil composition. The main components in the oil were butylated hydroxytoluene (BHT) (34.17%), phytol (12.66%), α-caryophyllene (11.84%), δ-elemene (10.65%), β-caryophyllene (7.82%), γ-elemene (4.24%) and germacrene D (2.82%). The antioxidant activity of the oil was evaluated in terms of their free-radical scavenging activity against 1,1-diphenyl-2-picrylhydrazyl. The oil showed percentage inhibition of 35.62% and 75.25% at concentrations of 76 and 101.6 mg mL⁻¹, respectively. BHT (36.30%) was also determined by HPLC-DAD in the hexane fraction from the leaves. To the best of our knowledge, this is the first study of the composition and antioxidant activity of the essential oil of the species V. megapotamica.

Keywords:

• Vitex megapotamica
• essential oil
• butylated hydroxytoluene
• antioxidant capacity

Acknowledgements

The authors would like to thank the professors from NAPO (Center for Analysis and Organic Research at UFSM) for providing the GC–MS chromatograms and spectra and A.F. Morel (Department of Chemistry at UFSM) for the assessment of the n-alkane series. The authors thank the financial support of CAPES (Coordenação de Aperfeiçoamento de Pessoal de Nível Superior), Brazil.