Phytochemical screening, Cytotoxic, genotoxic and mutagenic effects of the aqueous extract of Azadirachta indica leaves

Abstract

Azadirachta indica is a medicinal plant used to treat a various number of diseased conditions such as malaria, cough, asthma, diarrhea and diabetes. In traditional medicine, the aqueous concoction of the leaves is used to treat malaria. The phytochemical screening of the aqueous extracts from the leaves of A. indica have been shown to contain tannins, saponins, terpenoids, glycosides, steroids, flavonoids and glycosides. Previous studies on the phytochemical screening of Azadirachta indica leaves have shown the presence of tannins, saponins, terpenoids, glycosides, phytosterols, flavonoids and glycosides. Four different concentrations of the extracts were used to treat the roots of Allium cepa seedlings. In the Allium cepa assay, the extracts exhibited cytotoxic effects, expressed as the decrease in the root growth length when the concentrations increased. The EC50 was 0.21g/l. The extract induced an increased mitodepressive effect and chromosomal aberrations in the Allium cepa cells as the concentrations increased. The results with a p-value < 0.05 were considered as statistically significant compared to the untreated group in distilled water. The observed chromosomal aberrations appeared as c-mitosis, chromosomal fragments, microbridges, bipolar and multipolar anaphases. The aqueous extracts of A. indica leaves have also shown to cause mutation in Salmonella typhimurium TA 98 and TA 100 strains. Therefore the leaves of a indica have a genotoxic effect on chromosomes and also can cause mutations in cells. However the potential genotoxicity of the aqueous extract of Azadirachta indica leaf in human cells needs has not been established.