Andeden Enver Ersoy, Ozturk Sahlan, Aslim Belma
Department of Molecular Biology and Genetics, Nevsehir Haci Bektas Veli University, Nevsehir, Turkey.
Department of Environmental Engineering, Nevsehir Haci Bektas Veli University, Nevsehir, Turkey.
Curr Microbiol. 2021 Feb;78(2):775-788. doi: 10.1007/s00284-020-02340-5. Epub 2021 Jan 21.
Microalgae are considered feedstock for biodiesel production due to their capability to accumulate triacylglycerols, which have a 99% conversion rate into biodiesel, under certain conditions. This study aims to evaluate thirty native microalgal strains as feedstock for biodiesel production based on their biomass and lipid productivities, and total lipid and triacylglycerol contents under nitrogen-sufficient and nitrogen starvation conditions. In addition, Chlamydomonas reinhardtii cw15 mutant strain was utilized as a reference strain for triacylglycerol accumulation. Among the eight potent strains, Chlorella vulgaris KP2 was considered as a most promising strain with the highest triacylglycerol content, highest total lipid content (28.56% of dry cell weight), and the highest lipid productivity (4.56 mg/L/day) under nitrogen starvation. Under nitrogen starvation, the major fatty acids in the triacylglycerol of Chlorella vulgaris KP2 were C18:1 (37.56%), C16:0 (23.16%), C18:0 (23.07), C18:2 (7.00%), and C18:3 (3.12%), and the percentages of saturated fatty acids, monounsaturated fatty acids, and polyunsaturated fatty acids represented 49.26, 38.73, and 10.12% of the total fatty acids, respectively. Furthermore, the fatty acid methyl esters of triacylglycerol displayed remarkable biodiesel properties with a lower iodine value (59.00 gI/100 g), higher oxidative stability (14.24 h) and higher cetane number (58.73) under nitrogen starvation. This study suggests that nitrogen-starved Chlorella vulgaris KP2 could be used as a feedstock for biodiesel production due to the considerable amounts of triacylglycerol and favorable biodiesel properties.
微藻因其在特定条件下积累三酰甘油的能力而被视为生物柴油生产的原料，三酰甘油转化为生物柴油的转化率达99%。本研究旨在基于30种本地微藻菌株在氮充足和氮饥饿条件下的生物量、脂质生产率、总脂质和三酰甘油含量，评估其作为生物柴油生产原料的潜力。此外，莱茵衣藻cw15突变株被用作三酰甘油积累的参考菌株。在8株优势菌株中，普通小球藻KP2被认为是最具潜力的菌株，在氮饥饿条件下，其三酰甘油含量最高、总脂质含量最高（占干细胞重量的28.56%），脂质生产率最高（4.56毫克/升/天）。在氮饥饿条件下，普通小球藻KP2三酰甘油中的主要脂肪酸为C18:1（37.56%）、C16:0（23.16%）、C18:0（23.07%）、C18:2（7.00%）和C18:3（3.12%），饱和脂肪酸、单不饱和脂肪酸和多不饱和脂肪酸分别占总脂肪酸的49.26%、38.73%和10.12%。此外，在氮饥饿条件下，三酰甘油的脂肪酸甲酯表现出显著的生物柴油特性，碘值较低（59.00 gI/100 g）、氧化稳定性较高（14.24小时）和十六烷值较高（58.73）。本研究表明，氮饥饿的普通小球藻KP2由于含有大量三酰甘油且具有良好的生物柴油特性，可作为生物柴油生产的原料。
