Study on the effects of different culture conditions on the morphology of Agaricus blazei and the relationship between morphology and biomass or EPS production

Agaricus blazei Murill has recently been shown to have strong immunomodulatory and anti-cancer properties. Two factors contribute to the development of particular morphological forms, and meanwhile fungal morphology directly or indirectly influences the productivity of fungal fermentations. Therefore, the present study was undertaken in order to optimize submerged culture of A. blazei for the highest amount of biomass and EPS production, and to evaluate the relationship between culture conditions, morphology and productivity of this mushroom in submerged culture. Different carbon and nitrogen sources at different pH were applied in submerged cultured A. blazei Murill. Morphological parameters (circularity, compactness and mean diameter) were determined, and the relationships between pellet morphology, biomass and EPS productivity were evaluated, applying different statistical tests. According to our results, starch and yeast extract were the best carbon and nitrogen sources for both mycelia biomass and EPS production. Small feather-like fluffy and loosely packed pellets with a small compacted central core can be introduced as desirable morphological features of A. blazei producing the highest biomass and EPS in these media.