中文摘要：

本文用实验室现有菌株Y17,直接利用海水进行发酵,并利用废弃的油脂作为碳源。通过测定发酵液的表面张力、排油圈、鼠李糖脂含量,结合傅里叶红外光谱分析,探究产表面活性剂培养基的盐度对产表活性能的影响以及海水发酵对生物表面活性剂产量和结构的影响。结果显示,盐度梯度和发酵产量呈负相关,在发酵产量上海水发酵培养基优于近似盐度的合成培养基,利用陈家港海水进行发酵后的发酵液中鼠李糖脂产量为17.33 g/L,接近0.5%NaCl浓度下的发酵产量20.5 g/L,但成本却比合成培养基低的多。同时傅里叶红外光谱分析表明海水发酵的产物是鼠李糖脂。实验证明海水发酵在理论上是可行的,本研究为进行海水发酵及其在沿海地区的产业化奠定了基础。

英文摘要：

In this study,one isolated strain Y17 was used for fermentation with seawater by using the waste vegetable oil as the sole carbon source .The surface tension , oil expelling circle and rhamnolipid concentration were measured .By combining with Fourier transform infrared spectroscopy ( FIR) analysis, the influences of salinity of culture media were indicated on biosurfactant producing capacity and the influences of seawater fermentation on biosurfactant production and structure were explored .The experimental results showed that negative correlation was observed between the fermentation yield of rhamnolipid and salt concentration of culture media and in fermentation yield the seawater fermentation media performed better than synthetic media with similar salinity .The rhamnolipid production in fermented broth by Chenjiagang seawater was 17.33 g/L, close to that of synthetic media with 0.5%NaCl,while the fermentation cost was much lower than synthetic media .At the same time, Fourier transform infrared spectroscopy showed that rhamnolipid fermentation was the product of the seawater .The experiments proved that the seawater fermentation was feasible in theory .This study laid foundation for seawater fermentation and its industrialization in coastal areas .