In today’s scenario, microalgae are widely recognized 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. | American Journal of Biochemistry and Biotechnology 7 (3): 124-129, 2011 ISSN 1553-3468 © 2011 S. Nigam et al., This open access article is distributed under a Creative Commons Attribution (CC-BY) license Effect of Nitrogen on Growth and Lipid Content of Chlorella pyrenoidosa Subhasha Nigam, Monika Prakash Rai and Rupali Sharma Amity Institute of Biotechnology, Amity University, Noida, Uttar Pradesh, India Abstract: Problem statement: In today’s scenario, microalgae are widely recognized 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 nitrogen source ( g L−1 KNO3) on growth and lipid content was studied. Results: As the nitrate concentration in the medium decreased, biomass production also decreased but the lipid content increased. Moreover, at the same concentration of nitrate source, lipid tends to accumulate more in stationary phase in comparison to exponential phase. Highest lipid accumulation of 26% was recorded in the culture with g L−1 KNO3, which is onefourth of basal nitrogen source concentration. Conclusion: The present study suggested that nitrogen starvation is the effective approach to enhance lipid for biofuel production. Key words: Microalgae, lipid content, nitrogen source, KNO3, biofuel, comparison to exponential, grown autotrophically, batch culture, Triacylglycerols (TAGs) Gu, 2010). These TAGs are the sustainable feedstock for biodiesel production. Microalgae are far more efficient and can be grown in non-arable land, utilize waste water and do not compete with food crops for land and water (Chisti, 2007). They are renewable and environment friendly as they have the ability to fix CO2 and so can also be an interesting .
