State Key Laboratory of Materials-Oriented Chemical Engineering, College of Food Science and Light Industry, Nanjing University of Technology, No. 5 Xinmofan Road, Gulou District, Nanjing 210009, China.
Bioprocess Biosyst Eng. 2011 Jan;34(1):95-102. doi: 10.1007/s00449-010-0450-6. Epub 2010 Jul 17.
Batch fermentative production of welan gum by Alcaligenes sp. CGMCC2428 was investigated under various oxygen supply conditions using regulating agitation speed. Based on a three kinetic parameters analysis that includes specific cell growth rate (μ), specific glucose consumption rate (q (s)), and specific welan formation rate (q (p)), a two-stage agitation speed control strategy was proposed to achieve high concentration, high yield, and high viscosity of welan. During the first 22 h, the agitation speed in 7.5 L fermenter was controlled at 800 rpm to maintain high μ for cell growth. The agitation was then reduced step-wise to 600 rpm to maintain a changing profile with stable dissolved oxygen levels and obtain high qp for high welan accumulation. Finally, the maximum concentration of welan was reached at 26.3 ± 0.89 g L(-1) with a yield of 0.53 ± 0.003 g g(-1) and the welan gum viscosity of 3.05 ± 0.10 Pa s, which increased by an average of 15.4, 15.2, and 20.1% over the best results controlled by constant agitation speeds.
采用调节搅拌转速的方法，在不同供氧条件下，研究了希瓦氏菌 CGMCC2428 分批发酵生产结冷胶的情况。基于包括比细胞生长速率（μ）、比葡萄糖消耗速率（q（s））和比结冷胶形成速率（q（p））在内的三个动力学参数分析，提出了一种两阶段搅拌速度控制策略，以实现高浓度、高产量和高结冷胶黏度。在 7.5 L 发酵罐中，前 22 h 将搅拌速度控制在 800 rpm，以保持高μ促进细胞生长。然后逐步降低搅拌速度至 600 rpm，以保持稳定的溶解氧水平和获得高 qp，从而实现高结冷胶积累。最终，结冷胶的最大浓度达到 26.3±0.89 g/L，产率为 0.53±0.003 g/g，结冷胶黏度为 3.05±0.10 Pa·s，与恒速搅拌控制的最佳结果相比，分别提高了 15.4%、15.2%和 20.1%。
