Abstract
Various biotechnological methods coupled with potential microbial strains are developed to obtain potential natural compounds especially for pharmaceutical purposes such as antibiotics. Studies to find elicitors have been being performed with outstanding influence on obtaining accumulation of natural compounds. 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 with microbial pathogen as biotic elicitors, Staphylococcus aureus. The 14 days fermentation was carried out, then the media extracted with ethyl acetate. The ethyl acetate crude extract was evaporated, then the concentrate dissolved in methanol. Phytochemicals test, thin layer chromatography (TLC) and high performance liquid chromatography (HPLC) were applied to the extracts for identification. Antimicrobe test was performed by the disc diffusion method toward Gram negative and Gram positive bacterial pathogens. The result of phytochemical test showed both extracts contained terpenoid, however there was not phenolic compound on extract with biotic stimulation. Crude extract identification using TLC and HPLC showed some stains and peaks under UV detector on both extracts. The crude extract of metabolites could inhibit these pathogen microorganisms with different inhibition scale, while extract with biotic stimulation has higher activity. Production method of Penicillium sp. LBKURCC34 stimulated S. aureus was more effective method due to could produce metabolites that could give better inhibition toward these pathogens.