Antimicrobial Activity And Gc-Ms Analysis Of Aspergillus Clavatus

The culture filtrate of Aspergillus clavatus isolated from mangrove environment grown in corn meal broth was extracted and antimicrobial potential was tested. And filtrates were extracted with four different solvents, such as ethanol, ethyl ether, ethyl acetate and methanol. Their antimicrobial potential was tested against eight pathogenic bacteria and two fungi. The antimicrobial activities were evaluated by agar well diffusion method. The results of the screening revealed the strongest antibacterial and antifungal activities by the ethyl acetate extract followed by methanol, ethanol and ethyl ether. Crude extract showed the weakest inhibition. A.clavatus showed minimum inhibitory activity against Salmonella typhi, Salmonella paratyphi B and one fungal pathogen, Cryptococcus neoformans. But, the extracts showed maximum activity of inhibition against the other bacterial pathogens such as Staphylococcus aureus, Bacillus subtilis, Escherichia coli, Klepsiella pneumoniae, Proteus vulgaris, and Candida albicans. Influence of nutrients and physico-chemical parameters on the production of antimicrobial compounds was investigated so as to find out the optimum culture condition for maximum antimicrobial activity was performed. Based on this investigation, corn meal liquid medium, 9 days of incubation, 30oC temperature, pH 8, salinity 3% and the dextrose as carbon source were considered to be the optimum conditions for the maximum production of antimicrobial compounds, in vitro condition. Chromatogram of GC-MS analysis of the extract of A.clavatus showed the presence of 5 sets of major peaks and the components corresponding to the peaks were determined.