中文摘要：

【目的】探讨3种能源微藻细胞数量和藻液光密度之间的相关性，验证以光密度法测定细胞生长密度的可行性，为能源微藻的生长和生理生化研究提供简便方法与参考依据。【方法】选取三角褐指藻Phaeodactylumtricomutum、亚心形扁藻Platymonassubcordiformis和海洋小球藻Chlorellavulgaris3种能源微藻为生物材料，以添加f／2营养液的人工海水为培养介质，在植物培养箱中利用三角瓶进行一次性培养试验。利用显微镜计数法观测微藻的细胞密度，测定各藻液在680nm处的光密度值，并进行线性拟合获取回归方程，比较两种测定方法所得的藻细胞密度值。【结果】3种能源微藻的细胞密度与藻液光密度有显著的线性正相关，其回归方程分别为：三角褐指藻细胞密度（10^4个／mL）=14050D680-59．745，R2。=0．9942；亚心形扁藻细胞密度（104个＊／mL）=216．94OD680＋O．9743，R2=0．9947；海洋小球藻细胞密度（10^4个／mL）=2170．1OD680＋18．569，RZ=0．9927。在各微藻生长第5、7和9d中，利用显微镜计数法所得细胞数目和光密度法换算所得细胞数目没有明显差别。【结论】光密度法是一种可测定微藻细胞生长的快速、简便、有效的方法，可广泛应用于能源微藻的生长、生理生化研究。

英文摘要：

[Objective]The present study aimed to investigate the correlation between cell number and solution optical density （OD） of three energy microalgae and to explore the possibility of using the OD method to determine the cell growth density in order to provide a simple method and scientific base to better study the growth and physio- chemistry of energy microalgae. [Method ]Phaeodactylum tdcornutum, Platymonas subcordiformis, and Chlorella vulgans were cultured in artificial seawater enriched with f/2 solution in a plant growth chamber. Cells were counted with the help of a hemacytometer under microscope, and the OD of microalgal solution at wavelength of 680 nm was mea- sured. The regression equations were obtained by linear fitting, and the cell densities calculated by the cell count method and the OD method were compared and validated. [Result]There was a significant positive correlation between the cell numbers and OD~0 value. The regression equations were y=1405x-59.745 （R2=0.9942）, y=216.94x＋0.9743 （R2=0.9947）, and y=2170.1x＋18.569 （R2=0.9927） for P. tricomutum, P. subcordiformis, and C. vulgaris, respectively. The cell densities directly counted under the microscope were close to those converted from the regression equations. [ Conclusion ]The OD method was tested to be quick, simple, and efficient for determining microalgal cell growth, which could be widely apolied in the m＇owth and phvsioehemieal studies on energy mieroalgae.