ABSTRACT
Aims: To isolate and characterize an antimicrobial peptide from fruiting bodies of Lentinus squarrosulus Mont., the Thai common edible mushroom. Methodology and results: Solid ammonium sulfate at 40-80% (w/v) final concentration was utilized to precipitate the proteins and further purified by ion exchange chromatography on DEAE-cellulose and gel filtration chromatography on Sephadex G-25. The peptide was adsorbed on DEAE-cellulose and Sephadex G-25. It appeared as a single band with a molecular mass of about 17 kDa (kilodalton) in sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Further investigation of antimicrobial properties of purified peptide revealed that it has no activity against both Gram positive and Gram negative bacteria. However, it exhibited strong antifungal activity against various species of fungal pathogen of human. Among the high sensitive strains, Trichophyton mentagrophytes, T. rubrum, and Candida tropicalis are clinical isolates. Moreover, the potency was found to be concentration dependent and comparable with Ketoconazole, the commercial antifungal drug. Conclusion, significance and impact study: In this work, the novel bioactive peptide from fruiting bodies of L. squarrosulus Mont. has been isolated. It shows potent activity against various clinical isolates of fungal pathogen of human. It may have potential for pharmaceutical application.
Subject(s)
Anti-Infective AgentsABSTRACT
Development of efficient substrate formulas to improve yield and shorten production time is one of the prerequisites for commercial cultivation of edible mushrooms. In this study, fifteen substrate formulas consisting of varying ratios of palm press fibre (PPF), mahogany sawdust (MS), Gmelina sawdust, wheat bran (WB), and fixed proportions of 1% calcium carbonate (CaCO3) and 1% sucrose were assessed for efficient Lentinus squarrosulus production. Proximate compositions of mushrooms produced on the different substrate formulas were also analysed and compared. Substrate formulations containing 85% PPF, 13% WB, 1% CaCO3, and 1% sucrose were found to produce the highest carpophore yield, biological efficiency and size (206.5 g/kg, 61.96%, and 7.26 g, respectively). Days to production (first harvest) tended to increase with an increase in the amount of WB in the substrate formulas, except for PPF based formulas. The addition of WB in amounts equivalent to 8~18% in substrate formulas containing 80~90% PPF resulted in a decrease in the time to first harvest by an average of 17.7 days compared to 80~90% MS with similar treatment. Nutritional content of mushrooms was affected by the different substrate formulas. Protein content was high for mushrooms produced on formulas containing PPF as the basal substrate. Thus, formulas comprising PPF, WB, CaCO3, and sucrose at 85% : 13% : 1% : 1%) respectively could be explored as starter basal ingredients for efficient large scale production of L. squarrosulus.