Abstract
The increased use of antimicrobial agents resulted in the development of resistance against most of the commonly used antimicrobial drugs. Therefore the need for safe and effective antimicrobial agent have increased with time. This study was designed in an attempt to search for such natural antimicrobial agents against fungi. A total of fifty five indigenous bacterial strains were collected from different clinical specimens. These strains were identified by conventional methods as Staphylococcus aureus, S. epidermidis, Bacillus subtilis, Pseudomonas aeruginosa, Proteus mirabilis and P. vulgaris. The cell free culture supernatant (CFS) of these strains were used in antifungal screening by using agar well diffusion assay against different fungal strains. Of all the bacterial strains screened, 36.4% (20/55) showed antifungal potential. However, S. aureus, B. subtilis and P. mirabilis demonstrated bioactivity against some fungal strains but 71.4% (15/21) strains of P.aeruginosa demonstrated significant antifungal activity. The most potent antifungal strains P. aeruginosa strains MS 9 and MS 10 exhibited antifungal activity against Rhizopus sp., Aspergillus spp., Penicillium sp., Microsporum sp., Trichophyton spp. and Saccharomyces species. However, no activity was recorded against Candida spp. The physico-chemical characterization of these two strains MS 9 and MS 10 revealed retention of bioactivity of these metabolites both at low temperature (00C and 40C) and at high temperature up till 700C. Similarly exposure to organic solvents such as ethanol, methanol and formaldehyde also had no effect on their antifungal potential. The findings suggest further purification and possible application of these metabolites as antifungal agent in future.
