副干酪乳杆菌副干酪亚种L1的培养条件及絮凝活性研究

Culture condition and flocculating activity of Lactobacillus paracasei subsp. paracasei L1

酸浆是我国传统的鲜薯(或绿豆)淀粉生产工艺中用于淀粉分离净化的生物絮凝剂。本实验对从自然发酵的甘薯酸浆中分离的、对甘薯淀粉具有高絮凝活性的副干酪乳杆菌副干酪亚种L1的培养条件和絮凝活性进行了研究。结果表明,副干酪乳杆菌副干酪亚种L1为兼性厌氧菌,在改良TJA培养基初始pH为7.0,在25℃培养48～60h时,菌体的生长状况和絮凝活性最好;Na+、K+对L1的絮凝活性有显著的增强作用,但对高温和胰蛋白酶敏感。

Sweet potato acid steeping liquor was a bioflocculant of separation and purification in sweet potato starch production. It was studied that the culture condition and flocculating activity of Lactobacillus paracasei subsp. paracasei L1 isolated from natural fermentation of sweet potato acid steeping liquor. Lactobacillus paracasei subsp. paracasei L1 was facultative aerobe. The optimal growth condition was regarded as follows：the optimum temperature and initial pH was 25℃ and 7. 0,and cultured for 48 ~ 60h. Na＋ and K＋ could promote the flocculant formation and the flocculation of L1 was sensitive to high temperature（50℃） and trypsin.