Elucidating the role of nutrients in C-phycocyanin production by the halophilic cyanobacterium Euhalothece sp.

Abstract

In this study, a novel halophilic cyanobacterium was isolated and identified as Euhalothece sp. KZN. This fast-growing strain had the ability to synthesise high yields (12 mg g−1) of C-phycocyanin (C-PC), a highly fluorescent blue light-harvesting pigment with numerous potential uses in the biotechnology and commercial sectors. This study elucidated the individual and interactive role of different nutrients in BG11 growth medium for enhancing C-PC production in Euhalothece sp. KZN. Nine components of BG11 medium were screened for their effects via fractional factorial design (FFD). The results revealed a significant influence of nutrients, viz. MgSO4, NaNO3 and minor nutrients (citric acid, EDTA-iron citrate, CaCl2 and Na2CO3) on C-PC yield. These three components were further explored for their optimum concentration for enhancing C-PC production using a central composite design. The optimum values for these essential nutrients were found to be as follows: 0.10 g L−1 of MgSO4, 1.67 g L−1 of NaNO3 and 10 mL L−1 of minor nutrients which resulted in a 280% increase in C-PC yield with predicted and actual values of 43.97 and 45 mg g−1, respectively. Euhalothece sp. KZN is a strong potential candidate for C-PC production and can be further exploited to produce this industrially valuable compound.