Effect of Nitrogen on Growth and Lipid Content of Chlorella pyrenoidosa

Abstract

Problem statement: In today's scenario, microalgae are widely recogni zed as a promising source for biofuel production as a renewable source of energy. They are exceedingly rich in oil, which can be converted to biofuel. This paper deals with one of the method to enhance the lipid content in microalgae. Approach: Microalga, Chlorella pyrenoidosa , was grown autotrophically in batch culture and the effect of different concentrations of nitro gen source (0-0.4 g L -1 KNO 3) on growth and lipid content was studied. Results: As the nitrate concentration in the medium decreas ed, biomass production also decreased but the lipid content inc reased. Moreover, at the same concentration of nitrate source, lipid tends to accumulate more in s tationary phase in comparison to exponential phase. Highest lipid accumulation of 26% was recorded in t he culture with 0.05 g L -1 KNO 3, which is one- fourth of basal nitrogen source concentration. Conclusion: The present study suggested that nitrogen starvation is the effective approach to enhance lip id for biofuel production.