M. MINI AND P.M. BEEBI RAZEENA
Abstract
Aspergillus flavus Link; Fr, A. niger Vantieghem and A. fumigatus Fresen are saprotrophic and pathogenic fungus with a cosmopolitan distribution. They cause pre-harvest and post-harvest infections in cereals and legumes. Many strains produce significant quantities of toxic compounds known as mycotoxins, which when consumed are toxic causing aspergillosis in human beings. The present study aims to screening the cytotoxic and antifungal activity of aqueous leaf extracts of Memycylon umbellatum Burm.f, Carallia brachiata (Lour.) Merr and the dry fruit extract of Artocarpus lakoocha Roxb collected from the laterite hills of Kasaragod district of Kerala against aflatoxin producing Aspergillus flavus, A. fumigatus and A.niger. The in vitro studies of aqueous leaf extract of Memycylon umbellatum Burm.f showed 81% inhibition on Aspergillus flavus, 75% inhibition on Aspergillus fumigatus and 88.8% inhibition on Aspergillus niger. Leaf extract of Carallia brachiata showed 87.5% inhibition on A. flavus, 93.75% inhibition on A.fumigatus and 94% inhibition on A.niger. Dry fruit extract of Artocarpus lakoocha Roxb showed 100 % inhibition on A.flavus, 62.5% inhibition on A.fumigatus and 77.7% inhibition on A. niger. The cytotoxic study of different concentration of Carallia brachiata leaf and dry fruit of Artocarpus lakoocha Roxb on root meristem of Allium cepa Linn showed chromosome aberrations such as chromosome lagging and fragmentations, diagonal Anaphase and metaphase, vacuolated and sickle shaped nucleus, ball metaphase and micronuclei. In 60% aqueous concentration of leaf and dry fruit extract and control have no chromosomal aberrations. From the antifungal and cytotoxic analysis reveals that these plant can prevent the malignancy of the cells and have good pharmacognostic properties due to the presence of phytochemicals against Aspergillus spp. These may have scope and prospects for many future biofungicides and medicines for uncontrolled growth of the cells. So these plants must be conserved and mass multiplied and save our earth.