马乳酒样乳杆菌(Lactobacillus kefiranofaciens)合成开菲尔多糖培养基组成的优化

Medium optimization for kefiran synthesis by Lactobacillus kefiranofaciens

研究了发酵培养基组成对Lactobacillus kefiranofaciens的菌体生长以及合成开菲尔多糖(Kefiran)的影响。通过比较L. kefiranofaciens利用各种糖类和麦芽汁的发酵情况,发现麦芽汁最利于菌体生长及发酵产糖;各种氮源对L. kefiranofaciens发酵影响不同,其中以酵母粉最好,采用一品鲜酵母粉发酵的最佳浓度为10%;正交实验和RSA方法确定对发酵影响显著的三个无机盐是MnSO4.4H2O、MgSO4.7H2O和KH2PO4,最佳用量为0.2g/L,1g/L,4g/L,此时发酵获得开菲尔多糖产量为2.6±0.05g/L。L. kefiranofaciens发酵生产开菲尔多糖96h时可达到最佳发酵结果。

The effects of meditum composition on the cell growth and kefiran synthesis were studied. Based on the comparison of several saccharides and malt extract, the malt extract was the best for the cell growth and kefiran synthesis. Nitrogen sources had influence on the L.kefiranofaciens fermentation and the yeast powder with 10% concentration was selected. Three inorganic salts, such as MnSO4 ·4H2O, MgSO4·7H2O and KH2PO4, were found to play an important role by using orthogonal design and RSA method. The production of 2.6g/L kefiran could be obtained after 96h fermentation by adding 0.2g/L MnSO4·4H2O,1g/ L MgSO4·7H2O and 4g/L KH2PO4 into the culture medium.