中文摘要：

研究了不同pH调控方式和不同5-氨基乙酰丙酸（ALA）浓度对小球藻生长及油脂积累的影响.在Mf2培养基中添加50mmol/L磷酸钾缓冲液和体积分数为5%的CO2均可维持培养液pH值为7.0~8.0,两者同时加入使小球藻的生物量质量浓度提高了186.4%.在4种不同培养基中分别添加0.597~59.7μmol/L的ALA均可提高小球藻的生物量和总油脂的质量浓度,其中在Mf2＋P＋C培养基中效果最好,添加2.98μmol/L的ALA使小球藻的生物量质量浓度提高了19.2%,总油脂的质量浓度提高了16.8%.优化ALA的添加方式后,小球藻的生物量和总油脂的质量浓度分别达1.66g/L和0.336g/L.外源ALA的浓度与小球藻生物量质量浓度的对应曲线呈＂N＂形,说明ALA在小球藻中有作为叶绿素合成前体和生长调节剂的两种作用机理.添加ALA对小球藻的比油脂含量及其组成影响不显著（P〉0.05）.

英文摘要：

The effects of different pH control methods and 5-aminolevulinic acid（ALA）concentrations on Chlorellagrowth and lipid accumulation were studied.The additions of 50mmol/L potassium phosphate buffer and volume fraction of 5% CO2either or both,in Mf2medium,could maintain culture medium pH within 7.0-8.0,and the biomass concentration of Chlorella was 186.4%increased by adding both phosphate buffer and volume fraction of 5% CO2.The addition of 0.597-59.7μmol/L exogenous ALA enhanced the biomass concentration and total lipid concentration in all four kinds of media.The best enhancement effect was received in Mf2＋P＋C medium.The addition of 2.98μmol/L ALA increased the biomass concentration and total lipid concentration by 19.2% and 16.8%,respectively.After further optimization of ALA adding methods,the biomass concentration and total lipid concentration reached as high as 1.66g/L and 0.336g/L,respectively.The relationship between exogenous ALA concentration and Chlorella biomass concentration was shown as an N-shaped curve,which indicated that ALA acted as not only precursor of chlorophyll,but also growth regulator in Chlorella.Moreover,the addition of ALA did not change the specific lipid content and lipid components remarkably（P0.05）.