Phytochemical analysis, cytotoxicity and genotoxicity of Psidium guajava L. (Myrtaceae) leaf extracts

Abstract

Psidium guajava is one of the oldest and widely used medicinal plants in the world. The leaves, bark, roots and immature fruits are used in African ethno-medicine because of their anti-inflammatory, anti-diarrhoeal and anti-microbial properties amongst others. The aim of this work was to determine the phytochemical profile of locally sourced mature Psidium guajava leaves and to also evaluate the cytotoxic and genotoxic properties of aqueous extracts of Psidium guajava leaves. Ethanol extracts of Psidium guajava leaves were subjected to analysis using GC-MS. Aqueous extracts were prepared by boiling pre-weighted fresh leaves in tap water and subsequently used in the Allium cepa assay. Analysis revealed terpene compounds (80.6%) as the most abundant phytochemical in ethanol extracts of the leaves. The results also revealed an overall significant concentration and time-dependent reduction in mitotic index (p ≤ 0.05). The value of EC50 was estimated to be 54.4 g/l. Examination of treated Allium cepa root tip cells revealed chromosomal aberrations including binucleation, bridges, distorted anaphase, clumping, vagrant chromosomes and c-mitosis. Aqueous leaf extracts of Psidium guajava leaves have genotoxic and cytotoxic potentials which should be seriously considered in its therapeutic applications.