以食品级原料进行植物乳杆菌发酵及其抗真菌活性的研究

Research on Antifungal Activity of Lactobacillus plantarum Fermented from Food Grade Medium

用食品级的大豆蛋白培养基代替MRS培养基进行植物乳杆菌发酵,并对其抗真菌活性进行研究,以期获得安全性较高的食品防腐剂.实验结果表明,植物乳杆菌IMAU10014发酵大豆蛋白培养基后的上清液对娄地青霉具有较高的抑菌活性.为了进一步提高植物乳杆菌IMAU10014发酵液抗真菌活性,对不同碳源、氮源、pH和温度进行单因素研究,并通过L9(34)正交实验优化得到最佳培养基组合及培养条件:葡萄糖20,g/L、大豆蛋白5,g/L、pH 6.5、温度37,℃植物乳杆菌IMAU10014发酵48,h时抑菌效果最佳.对抑菌物质的理化性质分析结果表明:植物乳杆菌IMAU10014发酵浓缩上清液的抑菌活性对温度的变化不敏感;抑菌活性随着pH的升高而降低,经过蛋白酶K和胰蛋白酶处理后抑菌活性有所降低.

In order to obtain high security food preservatives,MRS medium for the fermentation ofLactobacillus plantarum was replaced by food grade medium,which was composed of soyabean protein and glucose. The result showed that the high antifungal activity againstPenicillium roqueforti was observed in the liquid supernatant ofL. plantarumIMAU10014. After optimization of the fermentation medium,optimal conditions forL. plantarum IMAU10114 were obtained：glucose 20,g/L, soyabean protein 5,g/L,pH 6.5,and temperature 37,℃ for 48,h. Moreover,the physical and chemical chatacteristics of the antifungal substance were analyzed.L. plantarum IMAU10014 was resistant to temperature. The antifungal activity de-creased with the increase of pH value after the treatment of proteinase K and trypsin.