Identification, comparism of GC/ MS analysis and cytotoxicity of volatile constituents of essential oils in stem, root and leaves of Dioclea reflexa found in South- West, Nigeria

Abstract Dioclea reflexa is a plant from Fabaceae family which has been reported from previous studies to possesses pharmacological properties such as antioxidant and antiviral effects. However, no biological activity from its essential oil has been reported in literature. The aim of this work is to analyse the chemical constituents, cytotoxic activity and antioxidant capability of the essential oils from root, stem and leaves of the plant. Volatile oil was obtained via hydro-distillation using a Clevenger apparatus, and were subjected to GC-MS analysis on an Agilent 7809A. Cytotoxic assay was carried out using Brine Shrimp Test (BST), antioxidant assay was carried out using DPPH and FRAP. A total of 63 compounds dominated by 1,8-Cineole (11.9%), α-terpinyl acetate (7.30%) and Borneol acetate (6.37%) were found in the leaves, in the stem with α- terpinyl acetate (11.06 %), camphene (3.94%) and Borneol acetate (7.22%) dominated the compounds and in the root the major compounds includes 1,8-Cineole (6.04%), α-terpinyl acetate (6.78 %) and Borneol acetate (6.43 %). The oil obtained from D. reflexa root is more active than the oil obtained from leaves and stem with LC50 values of 1.0439, 1.8059 and 1.2826 µg/mL respectively. The oil from the leaves showed the least ferric radicals reducing ability with the value of 0.1950 mg Fe2+/g, while the stem showed the highest ferric radicals reducing ability with the value of 0.8751 mg Fe2+/g. The essential oil derived from the stem and root could be used in future application in the treatment of inflammatory diseases.