School of Environment Science and Civil Engineering, Jiangnan University, Wuxi, 214122, China; Jiangsu Engineering Laboratory for Biomass Energy and Carbon Reduction Technology, Wuxi, 214122, China.
School of Environment Science and Civil Engineering, Jiangnan University, Wuxi, 214122, China; Jiangsu Engineering Laboratory for Biomass Energy and Carbon Reduction Technology, Wuxi, 214122, China.
Chemosphere. 2022 Nov;307(Pt 1):135533. doi: 10.1016/j.chemosphere.2022.135533. Epub 2022 Jul 1.
Microalgae biomass production with starch wastewater (SW) is a promising approach to realize waste recovery and cost reduction due to the inherent copious nutrients and nontoxic compounds in SW. However, the application of this technique is significantly hindered by low biomass production on account of the poor photosynthetic efficiency of microalgae. In this regard, we proposed a photo-regulation strategy characterized by the adjusting of numbers of light/dark (L/D) cycles, and compositions of light wavelength, which was proved to be an effective method for stimulating intracellular photo electron transfer and enhancing photosynthetic efficiency, to boost microalgae biomass accumulation. Additionally, responses of the microalgae photo-biochemical conversion, and the wastewater treatment performance at various number of L/D cycles and light wavelengths were discussed. The experimental results indicated that the biomass production increased when the L/D period was increased from 2 h:2 h-12 h:12 h. When the L/D period was 2 h:2 h, the biomass production reached a maximum value of 1.28 g L, which was 19.6% higher than that of the control group when the L/D period was 12 h:12 h. Furthermore, with respect to microalgae growth under monochromatic light, the maximum biomass concentration (1.25 g L) and lipid content (32.2%) of Chlorella were achieved under blue light; whereas, the minimum values were attained under red light (1.05 g L and 19.3%, respectively). When the red light and blue light were mixed and supplied, the microalgae biomass productivity was higher than that under white light, and the highest lipid productivity was 109.0 mg L d under a blue: red ratio of 2:1. Moreover, gas chromatography analysis demonstrated that the methyl in the range of C16-C18 in the system was higher than 70%. Fatty acid methyl esters (FAMEs) containing palmitic acid (C16:0) and oleic acid (C18:1) are beneficial for production of biodiesel, and the quality of fatty acid methyl ester used in biodiesel production can be improved using microalgae cultured under the mixed wavelengths of blue and red. Finally, Chlorella was cultured in PBR and reached the peak concentration of 2.45 g L by semi-continuous process with the HRT regulation.
利用淀粉废水（SW）生产微藻生物质是一种很有前途的方法，可以实现废物回收和降低成本，因为 SW 中含有丰富的营养物质和无毒化合物。然而，由于微藻的光合效率低，这种技术的应用受到了很大的限制。在这方面，我们提出了一种光调控策略，其特点是调整光照/黑暗（L/D）周期的数量和光波长的组成，这被证明是一种有效的方法，可以刺激细胞内光电子转移，提高光合效率，从而促进微藻生物质的积累。此外，还讨论了不同 L/D 周期和光波长下微藻的光生化转化响应和废水处理性能。实验结果表明，当 L/D 周期从 2 h:2 h-12 h:12 h 增加时，生物质产量增加。当 L/D 周期为 2 h:2 h 时，生物质产量达到 1.28 g/L 的最大值，比 L/D 周期为 12 h:12 h 时的对照组高出 19.6%。此外，对于单色光下微藻的生长，小球藻在蓝光下达到最大生物量浓度（1.25 g/L）和最大脂质含量（32.2%）；而在红光下则达到最小生物量浓度（1.05 g/L）和最小脂质含量（19.3%）。当红蓝混合光供应时，微藻生物量生产力高于白光，在蓝：红比为 2:1 时，最高脂质生产力为 109.0 mg/L·d。此外，气相色谱分析表明，系统中 C16-C18 范围内的甲基含量高于 70%。含有棕榈酸（C16:0）和油酸（C18:1）的脂肪酸甲酯（FAMEs）有利于生物柴油的生产，使用红蓝混合波长培养的微藻可以提高生物柴油生产中脂肪酸甲酯的质量。最后，通过 HRT 调控，在 PBR 中培养小球藻，采用半连续工艺达到 2.45 g/L 的峰值浓度。
