Bioprocess Engineering, Wageningen University, P.O. Box 8129, 6700 EV Wageningen, The Netherlands.
Mar Biotechnol (NY). 2010 Nov;12(6):708-18. doi: 10.1007/s10126-010-9258-2. Epub 2010 Feb 23.
The biomass yield on light energy of Dunaliella tertiolecta and Chlorella sorokiniana was investigated in a 1.25- and 2.15-cm light path panel photobioreactor at constant ingoing photon flux density (930 µmol photons m⁻² s⁻¹). At the optimal combination of biomass density and dilution rate, equal biomass yields on light energy were observed for both light paths for both microalgae. The observed biomass yield on light energy appeared to be based on a constant intrinsic biomass yield and a constant maintenance energy requirement per gram biomass. Using the model of Pirt (New Phytol 102:3-37, 1986), a biomass yield on light energy of 0.78 and 0.75 g mol photons⁻¹ and a maintenance requirement of 0.0133 and 0.0068 mol photons g⁻¹ h⁻¹ were found for D. tertiolecta and C. sorokiniana, respectively. The observed yield decreases steeply at low light supply rates, and according to this model, this is related to the increase of the amount of useable light energy diverted to biomass maintenance. With this study, we demonstrated that the observed biomass yield on light in short light path bioreactors at high biomass densities decreases because maintenance requirements are relatively high at these conditions. All our experimental data for the two strains tested could be described by the physiological models of Pirt (New Phytol 102:3-37, 1986). Consequently, for the design of a photobioreactor, we should maintain a relatively high specific light supply rate. A process with high biomass densities and high yields at high light intensities can only be obtained in short light path photobioreactors.
在恒定入射光子通量密度（930 μmol 光子 m ⁻² s ⁻¹ ）下，研究了在 1.25 和 2.15 cm 光程板光生物反应器中杜氏盐藻和普通小球藻的光能生物量产量。在生物量密度和稀释率的最佳组合下，两种微藻在两种光路径下的光能生物量产量相等。观察到的光能生物量产量似乎基于恒定的内在生物质产量和每克生物质的恒定维持能量需求。使用 Pirt 模型（New Phytol 102:3-37, 1986），分别为 D. tertiolecta 和 C. sorokiniana 找到了光能生物量产量为 0.78 和 0.75 g mol 光子 ⁻¹ 和维持需求为 0.0133 和 0.0068 mol 光子 g ⁻¹ h ⁻¹ 。在低光照供应速率下，观察到的产率急剧下降，根据该模型，这与可利用光能向生物质维持的转移量增加有关。通过这项研究，我们证明了在高生物量密度下短光程生物反应器中观察到的光能生物量产量下降，因为在这些条件下维持需求相对较高。我们对两种测试菌株的所有实验数据都可以用 Pirt 的生理模型（New Phytol 102:3-37, 1986）来描述。因此，对于光生物反应器的设计，我们应该保持相对较高的比光供应量。只有在短光程光生物反应器中，才能在高光强下获得高生物量密度和高产量的过程。
