以地沟油为原料,以解脂耶罗维亚酵母菌(Yarrowia lipolytica)为发酵菌株,进行柠檬酸和胞内油脂的同时发酵。结果发现,发酵过程中柠檬酸和胞内油脂同时保持较高产量的最佳发酵条件为:接种量为5×108个细胞/L培养基,碳源质量浓度为80.0 g/L,摇床培养转速为180 r/min。在该条件下,柠檬酸和胞内油脂的产量分别达到33.6 g/L和44.9 g/100 g(细胞干重)。进一步研究发现,Y.lipolytica以地沟油为原料合成柠檬酸和胞内油脂的发酵过程包括3个阶段:细胞生长阶段、油脂合成阶段和柠檬酸合成阶段。地沟油转化为胞内油脂后,其脂肪酸饱和程度降低。

In this study,citric acid and lipid were simultaneously produced by Yarrowia lipolytica from illegal cooking oil. We found that the conditions for both high yields of citric acid and intracellular lipid were as follows: the optimal inoculum size was 5 × 108 cells / L medium; the best initial concentration of carbon resource was 80. 0 g / L;the rotate speeds of the cultivation was 180 r / min. Under these conditions the yields of citric acid and intracellular lipid reached 33. 6 g / L and 44. 9 g /100 g cell dry weight respectively. The whole fermentation contains three distinct phases,namely growth phase,lipogenic phase,and citric acid production phase. The fatty acid of intracellular lipid was more unsaturated compared to that of illegal cooking oil.