Bioresource Technology, Vol.187, 70-76, 2015
Economic process to co-produce poly(epsilon-L-lysine) and poly(L-diaminopropionic acid) by a pH and dissolved oxygen control strategy
This study tended to apply biorefinery of indigenous microbes to the fermentation of target-product generation through a novel control strategy. A novel strategy for co-producing two valuable homopoly (amino acid) s, poly(epsilon-L-lysine) (epsilon-PL) and poly(L-diaminopropionic acid) (PDAP), was developed by controlling pH and dissolved oxygen concentrations in Streptomyces albulus PD-1 fermentation. The production of epsilon-PL and PDAP got 29.4 and 9.6 g L-1, respectively, via fed-batch cultivation in a 5 L bioreactor. What is more, the highest production yield (21.8%) of similar production systems was achieved by using this novel strategy. To consider the economic- feasibility, large-scale production in a 1 t fermentor was also implemented, which would increase the gross profit of 54,243.5 USD from one fed-batch bioprocess. This type of fermentation, which produces multiple commercial products from a unified process is attractive, because it will improve the utilization rate of raw materials, enhance production value and enrich product variety. (C) 2015 Elsevier Ltd. All rights reserved.