Activities of Leaf Extracts of Cashew (<i>Anacardium occidentale</i> L.) and Pawpaw (<i>Carica papaya</i> L.) against Mycelia Growth of Aspergillus Species Obtained from Decayed Cashew Fruits

Abstract

The activities of leaf extracts of cashew ( Anacardium occidentale ) and pawpaw ( Carica papaya ) were investigated against mycelia growth of Aspergillus niger and Aspergillus flavus in vitro. The leaves were dried at 28±2°C for a period of 5 days after which they were grinded using a mechanized blender. The leaf extracts obtained using aqueous extraction was used for the antifungal assay. The concentration of the extracts used was 2% and 6% both for cashew and pawpaw. The phytochemical screening of each extracts was carried out. The antimicrobial activity of each extracts against each test isolate was assayed using agar well diffusion method. By 72 hours of incubation, the order of zones of inhibition of A. niger with the tested extracts and concentrations was 6% pawpaw leaf extract > 2% cashew leaf extract > 6% cashew leaf extract > Mancozeb > 2% pawpaw leaf extract. Similarly, the order of zones of inhibition of the tested extracts and concentrations against mycelia of A. flavus was 6% cashew leaf extract > Mancozeb > 2% cashew leaf extract > 6% pawpaw leaf extract >2% pawpaw leaf extract. The antifungal activity of the leaf extracts could be attributed to the different classes of phytochemical present in them.