National Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, PO Box 353, Beijing 100190, PR China.
J Biotechnol. 2011 Feb 10;151(3):271-7. doi: 10.1016/j.jbiotec.2010.12.012. Epub 2010 Dec 17.
The growth characteristics of microalgae under different light conditions (continuous or intermittent) are essential information for photobioreactor design and operation. In this study, we constructed a thin-layer (10mm) flat plate photobioreactor device with a light/dark (L/D) alternation system to investigate the growth of Spirulina platensis under two different light regimes: (1) continuous illumination in a wide range of light intensities (1.00-77.16 mW cm(-2)); (2) intermittent illumination in medium frequency (0.01-20 Hz). Specific growth rate and light efficiency based on biomass production were determined for each round of experiment. Four regions (light limited region, intermediate region, light saturated region and light inhibition region) were recognized according to the results under continuous illumination. Under intermittent illumination, when L/D frequency increased from 0.01 Hz to 20 Hz, specific growth rate and light efficiency were enhanced. However, the enhancement was different, depending on the applied light intensity and light fraction. The higher the light intensity, the greater the enhancement would be when L/D frequency increased from 0.01 Hz to 20 Hz; and the higher the light intensity, the lower the light fractions is needed to maintain light efficiency as high as that under continuous illumination in light limited region.
不同光照条件（连续或间歇）下微藻的生长特性是光生物反应器设计和运行的重要信息。本研究构建了一个具有光/暗（L/D）交替系统的薄层（10mm）平板光生物反应器装置，以研究在两种不同光照条件下螺旋藻的生长：（1）在较宽的光强范围内（1.00-77.16 mW cm(-2))进行连续光照；（2）在中频（0.01-20 Hz）下进行间歇光照。对于每一轮实验，都确定了基于生物量生产的比生长速率和光效率。根据连续光照下的结果，识别出四个区域（光限制区域、中间区域、光饱和区域和光抑制区域）。在间歇光照下，当 L/D 频率从 0.01 Hz 增加到 20 Hz 时，比生长速率和光效率得到提高。然而，增强效果因应用的光强度和光分数而异。当 L/D 频率从 0.01 Hz 增加到 20 Hz 时，光强度越高，增强效果越大；而且光强度越高，在光限制区域下维持与连续光照一样高的光效率所需的光分数就越低。
