Evaluation of Chitin-Glucan Complex Production in Submerged Culture of Medicinal Mushroom of Schizophilum commune: Optimization and Growth Kinetic

Background: Schizophyllum commune, is one of the important medicinal-fungi foods in the world. Due to its important constituents such as extracellular and intracellular polysaccharides, it is widely used in industry and medicine. One of the important polysaccharides of this fungus is chitin-glucan complex (CGC). The aim of this study was to investigate the growth of native fungus Schizophyllum commune isolated from northern forests of Iran and to optimize its CGC production in submerged cultivation. Materials and Methods: Growth kinetics studies of native Schizophyllum commune fungi of Iran and CGC production were performed and growth curves were plotted. In order to increase CGC production, optimization of culture medium was done by investigating independent variables of pH, inoculum percentage and aeration percentage by response surface methodology. Results: The results showed that the specific growth coefficient of Iranian native Schizophyllum commune (max µ) was 0.991-day. Tenth day was also selected as the best time for growth and production in the submerged medium. In optimum conditions, initial pH of 8.92, percentage of inoculum 9.99 and aeration percentage of 150 was obtained. After 10 days, the amount of dry cell weight was 13.05 g/L and the amount of chitin-glucan complex produced was 2.9 g/L.   Conclusion: Investigation of kinetic parameters of growth and production showed that the experimental data are in accordance with the logistic growth model with R2=0.9665 and the  Luedeking and Piret  model for production with R2 = 0.9439. The results also show that the initial pH has a significant effect on the growth of this fungus.