OBJECTIVES: This work focuses on the development of a simple cultivation strategy for exopolysaccharides (EPS) production using Ganoderma lucidum and submerged cultivation system.
METHODS: At first, the best medium supporting EPS production was chosen experimentally from the current published data. Second, like many EPS production processes, carbon and nitrogen concentrations were optimized to support the highest production of polysaccharides in the shake flask level. Furthermore, the process was scaled up in 16-L stirred tank bioreactor.
RESULTS: The results clearly demonstrated that the best cultivation strategy was cultivation under controlled pH conditions (pH 5.5). Under this condition, the maximal volumetric and specific yield of EPS production were, 5.0 g/L and 0.42 g/g, respectively.
CONCLUSION: The current results clearly demonstrate the high potential use of submerged cultivation system as an alternative to conventional solid-state fermentation for EPS production by G. lucidum. Furthermore, the optimization of both carbon and nitrogen sources concentration and scaling up of the process showed a significant increase in both volumetric and specific EPS production.
RESULTS: The amount of α-IFN2b extracted using automated microscale platform (49.2 μg/L) was comparable to manual osmotic shock method (48.8 μg/L), but the standard deviation was 2 times lower as compared to manual osmotic shock method. Fermentation parameters in MTP involving inoculum size, agitation speed, working volume and induction profiling revealed that the fermentation conditions for the highest production of α-IFN2b (85.5 μg/L) was attained at inoculum size of 8%, working volume of 40% and agitation speed of 1000 rpm with induction at 4 h after the inoculation.
CONCLUSION: Although the findings at MTP scale did not show perfect scalable results as compared to shake flask culture, but microscale technique development would serve as a convenient and low-cost solution in process optimization for recombinant protein.