Li Xiangpeng, Manuel Jacob, Slavens Shelyn, Crunkleton Daniel W, Johannes Tyler W
Russell School of Chemical Engineering, The University of Tulsa, Tulsa, OK, 74104, USA.
Appl Microbiol Biotechnol. 2021 Jan;105(2):587-597. doi: 10.1007/s00253-020-11068-y. Epub 2021 Jan 4.
Light management strategy can be used to improve algal biomass and nutrient production. However, the response of algal metabolism to different light qualities, especially their interaction with other environmental factors, is not well understood. This study focuses on the interactive effects of light quality and culturing temperature on algal protein content and carbohydrate content of C. reinhardtii. Three LED light sources (blue light, red-orange light, and white-yellow light) were applied to grow algae in batch cultures with a light intensity of 105 μmol/ms under the temperatures of 24 °C to 32 °C. The protein and carbohydrate content were measured in both the late exponential growth phase and the late stationary growth phase. The results revealed that there was an interactive effect of light quality and culturing temperature on the protein and carbohydrate content. The combined conditions of blue light and a temperature of 24 °C or 28 °C, which induced a larger algal cell size with a prolonged cell cycle and a low division rate, resulted in the highest protein content; the protein mass fraction and concentration were 32% and 52% higher than that under white-yellow light at 32 °C. The combined conditions of red-orange light and a temperature of 24 °C, which promoted both the cell division and size growth, enhanced the carbohydrate content; the carbohydrate mass fraction and concentration were 161% and 155% higher than that under white-yellow light at 24 °C. When there was temperature stress (32 °C) or nutrient stress, the effect of light quality reduced, and the difference of protein and carbohydrate content among the three light qualities decreased. KEY POINTS: • Studied light quality-temperature interactive effect on protein, carbohydrate synthesis. • Protein content was high under low cell division rate. • Carbohydrate content was high under high cell division and cell size growth rate.
光管理策略可用于提高藻类生物量和养分产量。然而，藻类代谢对不同光质的响应，尤其是它们与其他环境因素的相互作用，目前尚不清楚。本研究聚焦于光质和培养温度对莱茵衣藻蛋白质含量和碳水化合物含量的交互作用。采用三种LED光源（蓝光、红橙光和白黄光），在24℃至32℃的温度下，以105μmol/ms的光强进行分批培养藻类。在指数生长后期和稳定生长后期测定蛋白质和碳水化合物含量。结果表明，光质和培养温度对蛋白质和碳水化合物含量存在交互作用。蓝光与24℃或28℃的组合条件，诱导出更大的藻细胞尺寸，细胞周期延长且分裂率低，导致蛋白质含量最高；蛋白质质量分数和浓度比32℃下白黄光条件下分别高32%和52%。红橙光与24℃的组合条件，促进了细胞分裂和细胞尺寸增长，提高了碳水化合物含量；碳水化合物质量分数和浓度比24℃下白黄光条件下分别高161%和155%。当存在温度胁迫（32℃）或营养胁迫时，光质的影响减弱，三种光质下蛋白质和碳水化合物含量的差异减小。要点：• 研究了光质-温度对蛋白质、碳水化合物合成的交互作用。• 低细胞分裂率下蛋白质含量高。• 高细胞分裂和细胞尺寸增长率下碳水化合物含量高。
