利用乙醇发酵副产CO2培养富含淀粉亚心型四爿藻作为其补充原料

Ethanol production with starch-based Tetraselmis subcordiformis grown with CO2 produced during ethanol fermentation

摘要:

建立了乙醇发酵耦联微藻培养系统，研究了利用酿酒酵母Saccharomyces cerevisiae乙醇发酵副产CO2为碳源，培养富含淀粉的亚心形四爿藻Tetraselmis subcordiformis，作为乙醇发酵补充原料的可行性。在连续光照培养条件下，间歇式培养7 d，反应器中藻细胞密度达到2.0 g/L左右，胞内淀粉含量约45％。微藻细胞收集后，经超声处理和酶法水解，葡萄糖释放量为胞内淀粉总量的71.1％。S. cerevisiae发酵微藻生物质水解液生产乙醇，其得率达到理论值的87.6％。表明乙醇发酵耦联微藻培养可行，既减少了CO2向环境的排放，又收获了富含淀粉的微藻生物质作为乙醇发酵的补充原料，节省粮食类淀粉质原料的消耗。

Abstract:

A system coupling ethanol fermentation with microalgae culture was developed, in which CO2 produced during ethanol fermentation was used as carbon source for the growth of Tetraselmis subcordiformis, a microalgae accumulating starch intracellularly. The biomass concentration about 2.0 g DCW/L was achieved within the photobioreactor for the batch culture of 7 days, and intracellular starch accumulation was about 45%. Furthermore, ultra sonic pretreatment and enzymatic hydrolysis were applied to the microalgae biomass, and 71.1% of the intracellular starch was converted into glucose that was fermented sequently to ethanol by Saccharomyces cerevisiae with an ethanol yield of 87.6% of the theoretical value, indicating that the microalgae biomass could be an alternative feedstock for ethanol production to save grain consumption, and in the meantime mitigate the CO2 emission.