生物破乳剂产生菌混合培养及其发酵条件的优化

【目的】对菌株L1和XH1的混合发酵条件进行优化，为混合菌发酵生物破乳剂的实际生产和应用提供理论依据。【方法】利用响应面实验(RSM)的中心组合旋转设计方法(CCRD)针对混合菌的发酵条件进行优化，通过对模型乳状液进行破乳实验，以排油率作为发酵液破乳效能的评价标准。【结果】经模型的分析与验证，确定最佳发酵条件为：种子液比例(L1:XH1)为3:2，葡萄糖投加时间为第4天，投加葡萄糖后再培养21 h，液体石蜡含量3.6% (体积比)。【结论】与破乳菌XH1和L1单独培养相比，经混合培养后获得复合生物破乳剂具有投加量少、破乳接触时间短的优势。同时双株破乳菌复配培养有效地提高了培养基中主要营养物质的利用率，减少了对底物的浪费。

Mixed cultivation and optimization of fermentation conditions of demulsifying bacteria

[Objective] To provide theoretical basis for production and application of mix cultivated bio-demulsifier, the optimal conditions of mixed cultivation of strains L1 and XH1 were studied in this research. [Methods] Response surface methodology (RSM) based on the central composite rotation design (CCRD) was used to optimize fermentation conditions, and the demulsifying ratio was used to evaluate the demulsifying ability of fermentation broth. [Results] According to the results of the model analysis and verification, the optimal conditions were as follow: 3:2 inoculum proportion (strain L1:XH1), 3.6% (v/v) liquid paraffin contents, feeding glucose on the 4th day, and 21 h continuous incubation after feeding glucose. [Conclusion] Compared with single strain culture, the compound bio-demulsifier produced by complex culture of L1 and XH1 exhibited less dose and shorter demulsifying time. The complex culture increased the utilization ratio of main nutrients in the medium.