Biological activities of Schizophyllum commune FR

The increasing appearance of several multi-resistant pathogenic microorganisms and tumor cells to the available drugs has drawn much attention of researchers to find new alternative drugs. Drugs from natural sources are the best choice as many nonnatural, synthetic drugs are carcinogenic and cause severe side effects that were not acceptable by the consumers. The potential use of mushroom to explore their biological activities may be important for treatment of a variety of human ailments. Many mushroom species have become attractive as a source for the development of drugs and nutraceuticals as they contain a tremendous variety of secondary metabolites with diverse biological activities as they are nutritionally functional food and a source of physiologically beneficial and non-toxic medicines. In this present study, Schizophyllum commune Fr. , a split gill mushroom was chosen as it has long been acknowledged for its medical importance. Schizophyllum commune was extracted with methanol, ethyl acetate, dichloromethane and water and these extracts were tested. Antimicrobial activity was determined using the well diffusion assay. The microorganisms tested consisted of common pathogenic bacteria i.e Gram-positive bacteria (Bacillus cereus, B. subtilis, Enterobacter faecalis, Staphylococcus aureus, Streptococcus mitis, S. mutans and S. sanguis), Gram-negative bacteria (Escherichia coli, Salmonella sp., S. typhi, Shigella sp., Shigella flexneri, Plesiomonas shigelloides, Proteus vulgaris, and Pseudomonas aeuroginosa) and pathogenic fungi (Candida albicans, C. parapsilosis and Saccharomyces pombe). The effectiveness of the extracts depends on the extraction solvent and higher antibacterial activity was exhibited compared to antifungal activity. Dichloromethane extract was the most effective, being able to significantly (P<0.05) inhibit the growth of most of the Gram-positive bacteria, Gram-negative bacteria and fungi. The highest inhibition zone by this extract was against the Gram-positive bacteria, S. sanguis with zone diameter of 12 Â± 1 mm. The antioxidant potential of S. commune extracts was measured employing two methods namely DPPH radical scavenging system and Folin- iocalteau method respectively. The radical scavenging activity of S. commune extracts correlated well with the total phenolic content (r=0.8264). Among the extracts, methanol extract of S. commune showed the most remarkable antioxidant activity with the ability to reduce the stable radical DPPH to yellow-coloured diphenylpicrylhydrazine providing IC50 at only 0.145 Â± 0.01 mg/ml and having the highest total phenolic content of 1.72 Â± 0.05 mg GA/g extracts equivalent to 0.498 Â± 0.07 mg GA/g fruitbodies. The cytotoxicity of S. commune extracts against cervical cancer cell lines; CaSki, epidermoid cancer cell lines; KB, colon cancer cell lines; HT29 and intestinal colon cancer cell lines; HCT116 were evaluated using the neutral red cytotoxicity assay. All S. commune extracts tested were considered non-cytotoxic against the cancer cells tested having IC50 values of more than 20 I¼g/ml. However, dichloromethane extract was found to be effective against the intestinal colon cancer cell lines, HCT 116 with IC50 value of 14.71 Â± 2.0 I¼g/ml. The anti-HPV activity of S. commune extracts was carried out using immunohistochemistry method to determine the expression of E6 oncoprotein and the anti-HPV 18 E6 activity in the cervical cancer (CaSki) cell lines. All S. commune extracts showed a quite similar trend of inhibition against the CaSki cells. However, based on the qualitative appearance on the morphology and colorization of the cancer cells, methanol and dichloromethane extracts of S. commune were the best E6 protein inhibitor compared to ethyl acetate and water extracts. Schizophyllum commune needs to be further purified for the bioactive ingredients as it holds hope for the discovery of new drugs for the treatment of a variety of human ailments. To our knowledge, this is the first report on the broad spectrum of antimicrobial, antioxidant, cytotoxicity and anti-human papilloma virus of S. commune extracts.