title: Biodiesel quality and biochemical changes of microalgae Chlorella pyrenoidosa and Scenedesmus obliquus in response to nitrate levels.
abstract: Biodiesel quality associated with biochemical components of Chlorella pyrenoidosa and Scenedesmus obliquus under different nitrate levels were investigated. The highest lipid contents of 54.5% for C. pyrenoidosa and 47.7% for S. obliquus were obtained in nitrate absence. Carbohydrate peaked at 0.3gL(-1) with values of 40.7% for C. pyrenoidosa and 42.5% for S. obliquus. Protein content seemed species dependent, which decreased substantially to 11.2% in C. pyrenoidosa and 8.8% in S. obliquus under nitrate absence in present research. Better biodiesel quality (e.g. cetane number >58, iodine value <69) could be obtained from C. pyrenoidosa in nitrate absence and S. obliquus in 0.3gL(-1), where the highest saturated fatty acids (39.5 for C. pyrenoidosa, 31.2 for S. obliquus) and the lowest unsaturated fatty acids (60.5 for C. pyrenoidosa, 68.8 for S. obliquus) were obtained. These results suggest that microalgae grown in the presence of nitrogen may limit biodiesel quality.
authors.affiliation: State Key Laboratory of Microbial Metabolism and School of Life Sciences & Biotechnology, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, China; Biomass Energy Research Center, Shanghai Jiao Tong University, Shanghai 200240, China.
authors.forename: Hongqin
authors.initials: H
authors.lastname: Wu
authors.affiliation: State Key Laboratory of Microbial Metabolism and School of Life Sciences & Biotechnology, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, China; State Key Laboratory of Motor Vehicle Biofuel Technology, Nanyang 473000, China; Biomass Energy Research Center, Shanghai Jiao Tong University, Shanghai 200240, China. Electronic address: miaoxiaoling@sjtu.edu.cn.
authors.forename: Xiaoling
authors.initials: X
authors.lastname: Miao
mesh_terms: D056804:Biofuels / Q000592:standards* / Q000706:statistics & numerical data; D019149:Bioreactors; D002241:Carbohydrates / Q000032:analysis; D002708:Chlorella / Q000378:metabolism*; D003124:Colorimetry; D008055:Lipids / Q000032:analysis; D013058:Mass Spectrometry; D058086:Microalgae / Q000378:metabolism*; D009566:Nitrates / Q000378:metabolism*; D011506:Proteins / Q000032:analysis; D044444:Scenedesmus / Q000378:metabolism*; D013045:Species Specificity
chemical_list: D056804:Biofuels; D002241:Carbohydrates; D008055:Lipids; D009566:Nitrates; D011506:Proteins
keywords: Biodiesel quality; Chlorella pyrenoidosa; Fatty acid compositions; Nitrate levels; Scenedesmus obliquus