本文研究了不同生长期在培养基中添加柠檬酸钠和生物素对白色链霉菌生长及产ε-PL的影响，结果表明添加不同浓度柠檬酸钠对菌体生长的影响不明显，但对白色链霉菌ε-PL合成有正向促进作用。0 h添加2 g/L的柠檬酸钠可获得最大的ε-PL产量0.92 g/L。随着柠檬酸钠浓度的增加，ε-PL产量先增加后降低。在0 h添加2 g/L柠檬酸钠并在36 h添加300 μg/L生物素，发酵72 h后菌体干重和ε-PL产量分别达到了7.86 g/L和1.10 g/L，是空白对照组的1.30倍和1.93倍，说明外源添加柠檬酸钠和生物素对白色链霉菌发酵生产ε-PL有促进作用。

The effect of sodium citrate on ε-PL fermentation of S. albulus was investigated. The results showed that sodium citrate concentrations had slight effect on cell growth, but significantly affect the synthesis of ε-PL. The addition of 2 g/L sodium citrate at 0 h resulted in the highest ε-PL concentration of 0.92 g/L. By adding 2 g/L sodium citrate at 0 h and 300 μg/L biotin at 36 h to fermentation media, the cell dry weight and ε-PL yield reached the highest values of 7.86 g/L and 1.10 g/L, respectively, being 1.30 and 1.93 folds to the control respectively. It was demonstrated that sodium citrate and biotin will promote cell growth and ε-PL yield of fermentation of S. albulus.

广东省教育部产学研合作项目（2009B090300300）;国家自然科学基金项目（31271925）