Screening of medicinal plants against A. flavus

Infestation of Aspergillus flavus has been a threat to the important crops and human's health. The usage of synthetic fungicides have resulted into environmental and health issues hence making natural fungicides a more attractive option. This study aims to investigate the effectiveness of Cympbogon citratus and Nigella sativa against toxigenic Aspergillus flavus growth. C.citratus and N. sativa were purchased at Kota Samarahan. The leaves and seeds were dried at 60 °C for one to two days in drying oven. The dried leaves and seeds were then ground by using laboratory blender and extracted with 96% of ethanol. A. flavus was sub-cultured on potato dextrose agar (PDA). In this experiment, disc diffusion technique was used as antifungal assay where the extracts were diluted in DMSO and water resulting in 100%, 75%, 50% and 25% of the ethanolic extract of the plants.. Then, the plates were incubated at 72 hours at 37 °C in inverted position. The diameter of inhibition zone was measured in mm as antifungal activity. Results obtained suggest that both plants show the antifungal activity with 100%, 75, and 50% concentration of extracts. The higher the amount of extracts used, the higher the antifungal activity exhibited towards the fungi. However, at 25% concentration of extracts, neither plants show any antifungal activity. Last but not least, C. citratus exhibited higher antifungal activity compared to N. sativa