Effect of Variable Salinity and Phosphorus Culture Conditions on Growth and Pigment Content of Chlorella vulgaris

Background/Objective: Chlorella vulgaris, microalgae belonging to Chlorellaceae family is widely used as food supplement and as feedstock for biodiesel production. Hence, it is needed for clean and cost-effective algal production with a high yield of biomass. This study will determine the algal response under various growth conditions for high growth, biomass yield with high pigment content. Methods/ Statistical Analysis: In our study, experiments in controlled conditions with variable NaCl concentration (0.0M, 0.1M, 0.15M, 0.2M and 0.25 M) and variable phosphorus concentration (0.04 g/l, 0.02g/l, 0.01g/l and 0 g/l K₂HPO₄) were conducted to study the response of Chlorella vulgaris in respect to growth and pigment components. All experiments were conducted in triplicates and the results were studied statistically by SPSS PASW 18.0 for two ways ANOVA. Findings: Under variable phosphorus conditions in respect of days the significant increase in growth was observed between 14th day to 21st day after which stationary trend was observed. Also, when phosphorus concentration was decreased from 0.04g/l to 0.02 g/l, 0.01g/l and 0.0g/l the growth, biomass and pigment composition showed a declining trend. Culture growing at 0.04g/l of K₂HPO₄ concentration in medium showed highest growth (1.281 ± 0.003 d-1,, where d is number of days) with variable NaCl concentrations the cell growth was favored at minimum salt concentration and with the increase of NaCl from 0.0M to 0.25M the growth and pigment components showed a decline. In respect of days with variable NaCl, the growth showed a significant increase from zero-day to 21st day thereafter only slight increase was seen on the 28th day. This result goes in consensus with previous findings. Hence, Chlo isolated from Rajasthan region is adaptable to grow at low salinity andrella vulgaris control phosphorus (0.04 g/l) conditions for high biomass with high pigment content which can be used for high nutritive purposes. Improvement/Application: Chlorella vulgaris yields high biomass and pigments both at 0.0 Molar salinity and 0.04 g/l phosphorus concentration. These conditions were successfully applied to grow Chlorella vulgaris in lab conditions to get the highest yield of biomass with high pigment content.