应用煎炸废油发酵制备槐糖脂生物表面活性剂

Utilization of Waste Fried Oil for Production of Sophorolipid Biosurfactants by fermentation

摘要:

应用正交实验，优化了假丝酵母菌O-13-1以煎炸废油为油溶性碳源发酵槐糖脂的条件，并应用高效液相色谱-高分辨串联质谱（HPLC-MS/MS）鉴定了所产槐糖脂同系物的组成及结构。结果表明，经正交实验优化的O-13-1菌株以煎炸废油为底物制备槐糖脂的摇瓶发酵条件为：摇床转速200r/min，双碳源添加量均为90g/L，温度为25℃，接种量为体积分数12%，槐糖脂产量在菌株稳定生长期的后期即204h时达到最大，为57.64g/L；O-13-1菌株以煎炸废油为底物所合成槐糖脂由9种乙酰基取代的内酯型和酸型槐糖脂同系物构成，内酯型槐糖脂同系物所占质量分数达76%。基于摇瓶得到的以煎炸废油为油溶性碳源的优化发酵条件，O-13-1菌株在5L自动发酵罐中转速500r/min时发酵合成槐糖脂产量可达163.28g/L。以煎炸废油为碳源发酵槐糖脂的原料成本较普通大豆油降低18%，在有效降低槐糖脂生产成本的同时，实现了煎炸废油的资源化利用。

Abstract:

The fermentation conditions of sophorolipids (SLs) by Candida bombicola O-13-1 with waste fried oil (WFO) as lipid substrates were optimized through orthogonal experiment, and the structures of individual SL components were quantified and identified by HPLC-MS/MS. The results showed that the optimized conditions in shake-flask were determined as follows: agitation 200r/min, carbon source added amount 90g/L, temperature 25℃, inoculum size 12% (volume fraction). The highest yield of SLs of 57.64g/L was obtained at the end of the stationary phase of yeast cell growth, i.e. 204h. The products were composed of 9 kinds of acetylated lactonized and acidic SLs, and the lactonic forms accounted for up to 76% (mass fraction). Moreover, the yield of SLs was as high as 163.28g/L in a 5L automatic fermentor under the optimized conditions of shake-flask with the exception of agitating of 500r/min. The material cost of SLs fermentation with WFO as carbon source reduced by 18% compared with soybean oil, and the resource utilization of WFO could be realized while effectively reducing the production cost of SLs.