Kuppusamy M, Balaraman K
Vector Control Research Centre, Pondicherry, India.
Indian J Exp Biol. 1991 Nov;29(11):1031-4.
Cell yield and toxicity of B. thuringiensis H-14 was improved markedly by adopting a simple fed-batch fermentation technique based on controlling glucose concentration. Maintenance of steady glucose concentration (0.3-0.5%) in the culture medium was achieved by the continuous addition of concentrated glucose solution. Addition of glucose at 3 g/hr/l of culture starting from 3rd hr till 16th hr of fermentation was found to yield cell densities of 80 g/l (wet weight) which represented a nearly 3-fold increase over the batch mode. A fivefold increase in toxicity was obtained by fed-batch fermentation. Cultivation of B. thuringiensis H-14 to high cell densities had no negative effect on sporulation and toxin synthesis. The rate of pH drop and dissolved oxygen level were within manageable limits.
通过采用基于控制葡萄糖浓度的简单补料分批发酵技术，苏云金芽孢杆菌H-14的细胞产量和毒性得到了显著提高。通过连续添加浓缩葡萄糖溶液，可使培养基中的葡萄糖浓度保持稳定（0.3-0.5%）。发现在发酵第3小时至第16小时期间，以3 g/hr/l的培养物添加葡萄糖，可获得80 g/l（湿重）的细胞密度，这比分批模式增加了近3倍。补料分批发酵使毒性提高了5倍。将苏云金芽孢杆菌H-14培养至高细胞密度对芽孢形成和毒素合成没有负面影响。pH下降速率和溶解氧水平在可控范围内。
