Department of Chemical Engineering, University of Puerto Rico at Mayagüez, Puerto Rico.
Appl Biochem Biotechnol. 2010 Nov;162(7):1978-95. doi: 10.1007/s12010-010-8974-4. Epub 2010 May 6.
Microalgal oil is a potential energy source because it can be easily converted to fatty acid methyl ester or hydrocarbon type of diesel, and it is produced with relatively higher productivity compared with oil from plants and animals. Heterotrophic growth of microalgae is superior due to its high final product concentration; however, the cost of the raw materials is unacceptable if sugar is utilized as the carbon source. The aim of this study is to optimize the lipid accumulation of Chlorella protothecoides by using carbon sources other than glucose in heterotrophic and mixotrophic cultures. Different factors such as different carbon sources, carbon to nitrogen ratio, initial pH level, salinity, and rotational speed are studied in affecting the cell growth and the oil accumulation. Our experiments revealed that the heterotrophic and mixotrophic cultures of C. protothecoides grew better than autotrophic cultures. C. protothecoides can grow on glycerol or acetate, as well as on glucose. Several stress factors were confirmed or discovered to significantly increase the lipid content of microalgae cells. The replacement of glycerol and acetate as carbon sources for microalgae cultivations provides potential for waste utilization: glycerol from biodiesel industry and acetate from biohydrogen production.
微藻油是一种有潜力的能源，因为它可以很容易地转化为脂肪酸甲酯或烃类柴油，并且与植物和动物油相比，其产量相对较高。由于其最终产物浓度较高，异养生长具有优势；然而，如果利用糖作为碳源，那么原材料的成本是不可接受的。本研究旨在通过在异养和混合营养培养中使用除葡萄糖以外的碳源来优化小球藻的脂质积累。研究了不同的因素，如不同的碳源、碳氮比、初始 pH 值、盐度和转速，以影响细胞生长和油脂积累。我们的实验表明，小球藻的异养和混合营养培养比自养培养生长得更好。小球藻可以在甘油或醋酸盐，以及葡萄糖上生长。一些应激因素被证实或发现可以显著提高微藻细胞的脂质含量。用甘油和醋酸盐替代微藻培养的碳源为废物利用提供了可能性：生物柴油工业的甘油和生物氢气生产的醋酸盐。
