Approach to improve the productivity of bioactive compounds of the cyanobacterium Anabaena oryzae using factorial design

Cyanobacteria are one of the richest sources of biomedical relevant compounds with extensive therapeutic pharmaceutical applications and are also known as producer of intracellular and extracellular metabolites with diverse biological activities. The genus Anabaena sp. is known to produce antimicrobial compounds, like phycocyanin and others. The goal of this study was to optimize the production of these bioactive compounds. The Plackett-Burman experimental design was used to screen and evaluate the important medium components that influence the production of bioactive compounds. In this present study, eight independent factors including NaNO3, K2HPO4, MgSO4·7H2O, CaCl2, citric acid, ammonium ferric citrate, ethylene diamine tetraacetic acid disodium magnesium salt (EDTA-Na2Mg) and Na2CO3 were surveyed and the effective variables for algal components production of Anabaena oryzae were determined using two-levels Plackett-Burman design. Results analysis showed that the best medium components were NaNO3 (2.25 g l−1); K2HPO4 (0.02 g l−1); MgSO4 (0.0375 g l−1); CaCl2 (0.018 g l−1); citric acid (0.009 g l−1); ammonium ferric citrate (0.009 g l−1) and EDTA-Na2 (0.0015 g l−1) respectively. The total chlorophyll-a, carotenoids, phenol, tannic acid and flavonoid contents in crude extract of Anabaena oryzae were determined. They were 47.7, 4.11, 0.256, 1.046 and 1.83 μg/ml, respectively. The antioxidant capacity was 62.81%.