Bioprocess development for large scale production of anticancer exo?polysaccharide by pleurotus ostreatus in submerged culture

Abstract

In the recent years, mushroom derived active metabolites have emerged as an important class of bioactive compounds with several therapeutic applications. Most of the production methods were based on cultivation of mushroom on solid substrate in controlled temperature green house. For the production of bioactive compounds for therapeutic application, production should be carried out under sterile and well controlled condition. Thus, the interest of cultivation of mushroom in bioreactors for bioactive compound production was increased during the last few years. In the present study, mushroom cells were cultivated in submerged culture for the overproduction of anticancer exo-polysaccharides (EPS). Cell cultivation was optimized in fully controlled stirred tank bioreactor in batch and fed-batch culture to improve the process and to increase the anticancer EPS production. In the first part of this study, significant improvement in EPS production was achieved upon transferring the process from shake flask to 15 L bioreactor. Further development in the process was conducted through optimization of some process parameters in bioreactor batch culture. In fed-batch culture, among different feeding strategies, optimized glucose feeding based on using the in-line data for oxygen and carbon dioxide obtained from out-gas analyzer was the best. The maximal yield of EPS obtained was 2.1 g L-1 in optimized fed-batch culture. The obtained EPS was almost two fold higher than those obtained in batch culture.