Antifungal Activity from Co-Culture of a Local Fungus of Tropical Peat Swamp Soil, Penicillium sp. LBKURCC34 with Gram-Negative and Gram-Positive Bacteria

Abstract

Microorganism is important producer of novel bioactive natural products, particularly in the field of drug discovery. Co-culture methods is one of powerful emerging tools for enhancing the chemical diversity of microorganisms. This research used the local culture collection of Penicillium sp. LBKURCC34, the fungus isolated from peat soil of primary forest at Giam Siak Kecil Bukit Batu (GSKBB)-Biosphere Reserve in Riau Province, to produce secondary metabolites secreted to their growth media that was cultivated by two different Gram of bacterial pathogen, Escherichia coli and Staphylococcus aureus. The 14 days fermentation was carried out and the media was extracted with ethyl acetate. The ethyl acetate crude extract was evaporated, then the concentrate dissolved in methanol. Antifungal, Candida albicans test was performed by the disc diffusion and the resazurin-based turbidimetric method. This study found that the crude extract of the co-culture with S. aureus could inhibit C. albicans growth, while that extract of the co-culture with E.coli could not do. The value of minimum inhibitory concentration (MIC) of the potential extract was less than the positive control, Ketoconazole. It only has potency as bacteriostatic extract.