本文通过初筛和复筛考察不同乳酸菌的抗真菌活性,并将小麦胚芽油添加入乳酸菌培养液中进行发酵,旨在明确乳酸菌协同小麦胚芽油发酵对抗黑曲霉活性的影响。研究表明,小麦胚芽油不具有抑制黑曲霉生长的能力,而乳杆菌LF5发酵液抑菌率随着小麦胚芽油浓度的升高明显提升,且该现象具有菌株特异性。通过加热、中和pH、添加蛋白酶及过氧化氢酶发现,乳酸菌协同发酵上清液中的抗真菌活性物质主要由有机酸以及部分具有良好热稳定性的非蛋白类组分组成。此外,采用乳杆菌LF5协同小麦胚芽油发酵制备面包,在第5 d发现肉眼可见霉菌,与空白组(第2~3 d)相较具有显著抑制黑曲霉生长活性的作用,为乳酸菌在发酵米面食品中的应用提供了新的方向。
In this paper,the antifungal activities of different lactic acid bacteria were investigated by primary screening and secondary screening,and wheat germ oil was added to the culture medium of lactic acid bacteria for fermentation,in order to clarify the effect of lactic acid bacteria and wheat germ oil fermentation on the antifungal activity of Aspergillus niger. The results showed that wheat germ oil did not have the ability to inhibit the growth of Aspergillus niger,but the inhibition rate of LF5 fermentation liquid significantly increased with the increase of wheat germ oil concentration,and the phenomenon was strain specific. By heating,neutralizing pH,adding protease and catalase,it was found that the antifungal active substances in the supernatant of Lactobacillus cooperative fermentation were mainly composed of organic acids and some non protein components with good thermal stability. In addition,Lactobacillus fermentans LF5 was used to prepare bread with wheat germ oil fermentation. On the 5th day,mold was found to be visible to the naked eye,which significantly inhibited the growth activity of Aspergillus niger compared with the blank group,providing a new direction for the application of Lactobacillus in fermented food.