In-Vitro Efficacy of Botanical extracts for the Management of Aspergillus flavus growth in Tanzania

Abstract

Maize is one of the most important food and commercial crops in Tanzania but is vulnerable to pre-and postharvest contamination with aflatoxins produced mostly by Aspergillus flavus. This study evaluated the in-vitro antifungal efficacy of five locally available botanicals (Azadirachta indica, Calotropis procera, Euphorbia hirta, Jatropha curcas, and Ricinus communis) against the growth of A. flavus. The botanical leaves were collected mainly from the Kongwa district, while strains of Aspergillus species were isolated from maize grain from Kongwa and Morogoro rural districts during the cropping season 2021/2022. The effect of botanicals on the radial mycelium growth of A. flavus was tested at concentrations of 0.2 0.25, 0.3, and 0.35 g/mL. The inhibitory effect was proportional to the concentration of botanicals. The highest radial growth inhibition of A. flavus was exhibited by extracts of J. curcas (69.7%), R. communis (62.8%), A. indica (61.8%), and E. hirta (52.4%). The least mean inhibition was found in C. procera (45.7%) at a concentration of 0.35 g/ml. The antifungal effect of botanicals demonstrated in this study warrants further evaluation for pre-harvest management of Aspergillus species contamination under field conditions.