Abstract

The study aims to investigate the effect of photo-autotrophic cultural conditions on the productivity and biomass composition of Chlorella vulgaris. The following five photo-autotrophic cultural conditions were investigated: light intensity (4000, 10,500, 17,000, 23,000, 30,000 lux), temperature (25, 28, 32, 35, 40 °C), pH (6, 7, 8, 9, 10), CO₂ (0.03, 2.5, 5, 7.5, 10%) and NO₃⁻ (0, 250, 500, 750, 1000 mg/L). Results indicate that lipid and protein yields were increased by 3.19 fold and decreased by 1.47 fold, respectively, under NO₃⁻ deficiency (0 mg/L). Meanwhile, carbohydrate yield was increased by 1.39 fold in 5% CO₂. Further cultivation with parameters of the highest biomass productivity (10,500 lux, 28 °C, pH 8, 5% CO₂ and 500 mg/L NO₃⁻) achieved the maximum biomass productivity of 0.468 g/L/day. Moreover, cultivation with parameters of the highest lipid yield (23,500 lux, 40 °C, pH 8, 0.03% CO₂ and 0 mg/L NO₃⁻) achieved the maximum lipid yield of 43.70%. The major fatty acid methyl ester compositions produced were C20:0 (39.08%) and C16:0 (37.15%), producing biodiesel with high cetane number and oxidative stability. These promising results provide a comprehensive comparison regarding the effect of photo-autotrophic cultural conditions on microalgae biomass and its potential application as a biofuels feedstock.

摘要

本研究旨在探讨光自养培养条件对普通小球藻生产力和生物量组成的影响。研究了以下五种光自养培养条件：光照强度（4000、10,500、17,000、23,000、30,000 lux）、温度（25、28、32、35、40 °C）、pH（6、7、8、9） , 10)、CO ₂ (0.03, 2.5, 5, 7.5, 10%) 和 NO ₃ ^- (0, 250, 500, 750, 1000 mg/L)。_{结果表明，在 NO 3} ^-缺乏（0 mg/L）下，脂质和蛋白质产量分别增加了 3.19 倍和减少了 1.47 倍。_{同时，在 5% CO 2}条件下，碳水化合物产量增加了 1.39 倍. 以最高生物质生产力参数（10,500 勒克斯、28 °C、pH 8、5% CO ₂和 500 mg/L NO ₃ ^-）的进一步培养实现了 0.468 g/L/天的最大生物质生产力。此外，以最高脂质产量参数（23,500 lux、40 °C、pH 8、0.03% CO ₂和 0 mg/L NO ₃ ^-）的培养实现了 43.70% 的最大脂质产量。生产的主要脂肪酸甲酯组合物为 C20:0 (39.08%) 和 C16:0 (37.15%)，生产具有高十六烷值和氧化稳定性的生物柴油。这些有希望的结果提供了关于光自养培养条件对微藻生物量的影响及其作为生物燃料原料的潜在应用的全面比较。