ABSTRACT:
The fungal strain AJA1 was isolated from leaf litter sample and identified as Penicillium decumbens through 18S rRNA gene sequencing. The antimicrobial potential of Penicillium decumbens strain AJA1 was investigated against medically important pathogenic microorganisms. The mycelium obtained in the presence of four different nitrogen sources sodium nitrate, potassium nitrate, casein, and soybean meal was extracted with methanol and the extracts obtained were determined for antimicrobial and antioxidant properties. The Gram positive bacteria (Staphylococcus aureus, Bacillius subtilis) were effectively inhibited by obtained methanol extract, while Gram negative bacteria (Escherichia coli, Pseudomonas aeruginosa, Salmonella sp., Shigella sp., Proteus mirabilis, Kelbsiella sp., Enterococcus sp., and Alcaligens sp.) were resistant to the extracts. The antioxidant activity was evaluated by hydroxyl free radicals and 2,2-diphenyl-1-(2,4,6-trinitrophenyl) hydrazyl (DPPH). The determination of antimicrobial activity against test organisms indicated that the concentration of active components was directly influenced on the antimicrobial activity of the extracts obtained.