The aim of the study was to identify the optimum cultivation conditions for the microalgal growth and lipid production of the oleaginous microalga Chlorella pyrenoidosa Chick (IPPAS C2). Moreover, an appropriate NO3- concentration in the cultivation medium for maximized lipid accumulation was determined. The experimental design involved a biphasic cultivation strategy with an initial biomass accumulating phase under optimized light (400 μmol/m2 per s), temperature (25 °C), and elevated CO2 concentration in the air mixture (3%), followed by a mid-elevated CO2 concentration (0.5%) for lipid induction. The highest lipid yields of 172.47 ± 18.1 and 179.65 ± 25.4 mg/L per day were detected for NO3- concentrations of 100 and 150 mg/L. The optimization approach presented here led not only to the maximization of lipid yield but also to the development of a biphasic cultivation strategy easily applicable to the cultivation process without the necessity for algal cell harvesting between the first and second cultivation phases.

中文翻译：

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通过微藻小球藻小球藻脂质生产最大化的双相优化方法。

该研究的目的是确定油性微藻小球藻小球藻（IPPAS C2）的微藻生长和脂质产生的最佳培养条件。此外，确定了培养基中适当的NO3-浓度以使脂质积累最大化。实验设计涉及一种双相培养策略，即在优化的光照（400μmol/ m2 / s），温度（25°C）和空气混合物中的CO2浓度升高（3％）的条件下，初始生物质积累阶段。 -提高脂质诱导的CO2浓度（0.5％）。对于NO3浓度为100和150 mg / L的最高脂质产量为每天172.47±18.1和179.65±25.4 mg / L。