Abstract This study presents the mixotrophic cultivation of Scenedesmus sp. using crude glycerol (CG) obtained from lab scale biodiesel unit in an internal loop airlift photo-bioreactor (ALR) for enhanced biomass and lutein production. Prior to reactor studies, shake flask experiments were designed using Taguchi orthogonal array method to evaluate the influence of CG concentration, nitrogen to phosphorus ratio (N/P), and inhibitors concentration (methanol and KOH). Experimental run carried out with 5 g/l CG, 20:1 N/P ratio, 0.5 % methanol concentration, and 7.5 mg/l KOH produced a maximum biomass and lutein productivity of 310.18 mg/(l d) and 2.25 mg/(l d) respectively. During the mixotrophic cultivation of Scenedesmus sp. in an ALR, the step-wise addition of CG during the growth phase improved the productivity. The CG concentration of 6 g/l showed highest biomass and lutein productivity of 768 mg/(l d) and 3.59 mg/(l d), respectively. Monod and Logistic models were employed to fit the growth data. This study illustrated that the fed-batch strategy and mixotrophic cultivation offer higher biomass and lutein production.

中文翻译：

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通过混合营养培养栅藻提高生物量和叶黄素产量。在气升式光生物反应器中使用粗甘油

摘要 本研究介绍了栅藻的混合营养培养。在内部回路气升光生物反应器 (ALR) 中使用从实验室规模的生物柴油装置获得的粗甘油 (CG)，以提高生物量和叶黄素的产量。在反应器研究之前，使用田口正交阵列方法设计摇瓶实验以评估 CG 浓度、氮磷比 (N/P) 和抑制剂浓度（甲醇和 KOH）的影响。使用 5 g/l CG、20:1 N/P 比、0.5% 甲醇浓度和 7.5 mg/l KOH 进行的实验运行产生的最大生物量和叶黄素生产力分别为 310.18 mg/(ld) 和 2.25 mg/(ld) ） 分别。在栅藻的混合营养培养过程中。在 ALR 中，在生长阶段逐步添加 CG 提高了生产率。6 g/l 的 CG 浓度显示出最高的生物量和叶黄素生产力，分别为 768 mg/(ld) 和 3.59 mg/(ld)。使用 Monod 和 Logistic 模型来拟合增长数据。该研究表明，分批补料策略和混合营养培养可提供更高的生物量和叶黄素产量。