粘质沙雷氏菌高产发酵灵菌红素的工艺优化及抗病毒活性

为提高粘质沙雷氏菌S3菌株的灵菌红素产率，本研究对粘质沙雷氏菌S3发酵过程中重要的发酵条件参数和关键组分进行逐项优化，并验证了发酵液灵菌红素提取物对本氏烟草病毒的抑制效果。结果表明，最佳培养基配方为：丙三醇0.5%，蛋白胨1.5%，氯化钠0.5%，氯化钾0.25%；最佳发酵条件为：接种量为10%，装液量为60%~70%，pH恒定为6.0，培养温度为28℃，振摇速度160r/min，发酵周期为60h。在该发酵条件下，既有利于粘质沙雷氏菌菌体生长，又能够使灵菌红素的产量达到最大化。按照该优化条件进行发酵后，其灵菌红素提取物溶液喷施于接种TMV、CMV和PVY的本氏烟，烟叶中TMV、CMV和PVY病毒量分别为空白对照的12.61%、29.41%和17.69%，对病毒的抑制效果优于氨基寡糖素。试验所得的发酵制备条件能够提高灵菌红素产量，提取物具备显著抗病毒特性，具有产业化开发潜力和经济应用价值。

Process Optimization and Antiviral Activity of High Yielding Prodigiosin from Serratia Marcescens

In order to improve the yield of prodigiosin in the industrial fermentation of Serratia marcescens-S3, the important fermentation condition parameters and key components of the fermentation broth of Serratia marcescens-S3 were optimized, and the inhibitory effect of the extracts of fermentation broth on viral diseases was verified. The results showed that the best medium formulation was: 0.5% of glycerol, 1.5% of peptone, 0.5% of sodium chloride and 0.25% of potassium chloride. The optimal fermentation conditions were: 10% inoculum, 60%-70% loading, constant pH of 6.0, incubation temperature of 28 ℃, stirring speed of 160 r/min, and 60 h fermentation cycle, which not only facilitated the growth of Serratia marcescens-S3, but also maximized the production of prodigiosin. After fermentation under the optimized conditions, the extract solution of prodigiosin was sprayed on Nicotiana benthamiana inoculated with TMV, CMV and PVY, and the amount of TMV, CMV and PVY viruses in leaves was 12.61%, 29.41% and 17.69% of that in the blank control, respectively. The inhibitory effect on viruses was better than that of chitosan oligosaccharide. The fermentation conditions obtained from this study can improve the yield of prodigiosin, and the extracts have significant antiviral property, which has the potential for industrial development and economic application value.