溶氧状况对甘蔗糖蜜发酵产黄原胶的影响

Effects of oxygen conditions on xanthan gum production by sugar-cane molasses

黄原胶是一种具有重要商业价值的微生物胞外多糖,甘蔗糖蜜是糖厂生产过程中的主要副产品、是一种理想的发酵原料,利用甘蔗糖蜜发酵生产黄原胶具有一定的经济效益和社会效益。本研究在前期菌种选育和发酵条件优化实验的基础上,进一步研究了溶氧浓度对甘蔗糖蜜发酵生产黄原胶的影响,溶氧浓度是需氧发酵过程中提高产量的限制性因素,实验研究了氧载体、表面活性剂、摇床转速、装液量四个影响溶氧浓度的因素对甘蔗糖蜜发酵生产黄原胶的影响,实验结果显示:发酵液添加0.4%的Tween80,发酵至24h,再加入3%的大豆油,装液量150mL/500mL,摇床转速180r/min,28℃培养86h,在此条件下,黄原胶的产量为34.23g/L,是原始发酵液的1.55倍。实验结果表明:增加溶氧可以有效的增加黄原胶的发酵产量。

Xanthan gum is a microbial polysaccharide with great commercial value. Sugarcane molasses was the main by - product in sugar production, and it is a good fermentation raw material. Using sugar cane molasses to produce xan- than gum has both economic benefits and social benefits. Based on our previous experiments of strain screening and fer- mentation conditions optimization, further research on the concentration of dissolved oxygen was studied. Because dis- solved oxygen can increase the yield of fermentation. In this study, the dissolved oxygen, surface active agents, shak- er speed and liquid volume were. The results were ： The optimal Tween 80 concentration was 0.4%, 3% the soybean oil was added after fermentation for 24hours, the liquid volume was 150mL/500mL culture was shook at 180r/min at 28~C for about 86h. Under the above conditions, the xamthan gum content was 34. 23g/L, 55% higher than the initial fermentation conditions. The increase of dissolved oxygen can effectively increase the yield of xanthan gum.