A comparative study of phycobilliprotein production in two strains of Pseudanabaena isolated from Arctic and tropical regions in relation to different light wavelengths and photoperiods

Phycobiliproteins, which include phycocyanin, allophycocyanin and phycoerythrin, are the group of coloured accessory photosynthetic pigments present in cyanobacteria (blue-green algae). Pseudanabaena is a genus of microscopic cyanobacteria, cosmopolitan in distribution and known to be rich in phycoerythrins. Cyanobacteria are photosynthetic organisms, thus, one of the factors that influences their metabolism is the quality and quantity of incident light. In order to determine the production of phycobiliproteins (mainly phycocyanin and phycoerythrin) in this genus, the quantity of these pigments was investigated in two different strains of Pseudanabaena, P. catenata USMAC16 isolated from an Arctic location (Svalbard) and P. amphigranulata USMAC18 from a tropical location (Tasik Harapan, USM, Malaysia). The aims of this study were twofold. First, to determine the influence of different light wavelengths (white, green and red) and exposure duration (photoperiod of 12–24 h (h)) on phycocyanin and phycoerythrin production in the two strains. Second, to compare the production of phycobiliprotein between the two strains. Highest phycocyanin production was obtained under red light, while phycoerythrin production was highest under green light. Highest production was achieved with photoperiod 24:00 h L:D (L: light, D: dark) in the polar strain and 12:12 h L: D in the tropical strain. P. catenata (Arctic strain) was a good producer of phycoerythrin when grown under green light.

Details