Isolation, morphological and biopigments evaluation of the genera Nostoc and Anabaena (Nostocales) from Loktak Lake

Natural colourants such as phycobiliproteins are gaining importance over synthetic ones as they are non-toxic and non-carcinogenic. In this study, twenty-five (25) strains of Nostoc sp. and twenty-five (25) strains of Anabaena sp. from freshwater habitats of Loktak Lake were isolated, characterized and primarily screened for phycobiliproteins and chlorophyll-a. Among Nostoc genera, maximum amount of phycoerythrin was produced by Nostoc sp. BTA-61 (128.84±1.35 µgml-1). Nostoc commune BTA-67 produced maximum amount of both phycocyanin (130.55±10.41 µgml-1) and allophycocyanin (97.13±6.98 µgml-1). Nostoc commune BTA-67 also showed the maximum chlorophyll-a content (28.90±0.17 µgml-1). Within Anabaena sp., maximum phycocyanin amount was produced in Anabaena iyengarii BTA-74 (88.16±0.95 ?gml-1). Anabaena sp. BTA-964 (135.42±1.36 ?gml-1) and Anabaena sp. BTA-980 (50.71±1.70 ?gml-1) produced maximum amount of phycocyanin and allophycocyanin respectively. Anabaena iyengarii BTA-74 (16.43±0.17 ?gml-1) produced maximum amount of chlorophyll-a when compared to other Anabaena strains. These potent strains were found to be useful for industrial application.