Demirtas Meltem U, Kolhatkar Arati, Kilbane John J
Illinois Institute of Technology, Chemical and Environmental Engineering Department, Chicago, IL 60616, USA.
J Biosci Bioeng. 2003;95(2):113-7.
The growth kinetics of Thermus thermophilus HB27 was investigated in rich medium (Thermus medium) under batch cultivation at 65 degrees C in 3-l fermentors. The growth and oxygen consumption rates were highly dependent on the aeration and agitation rates. Volumetric mass transfer coefficient (K(L)a, h(-1)) and hence oxygen transfer rate (OTR, mol m (-3) h(-1)) into the fermentation broth increased with increased aeration and/or agitation rates. A K(L)a and OTR of 175.4 h(-1) and 31.7 mol m(-3)h(-1) respectively, corresponding to 500 rpm agitation and 2 vvm aeration with a mixture of air and oxygen, were required to avoid oxygen limitation. The maximum growth rate (mu(max), h(-1)), doubling time (t(D), h), and dry cell weight determined for T. thermophilus HB27 growing under these conditions were 0.27 h(-1), 2.67 h, and 3g/l respectively. This cell yield is higher than any previously published reports for growth of Thermus cultures, including studies that employed pressurized bioreactors.
在3升发酵罐中，于65℃下对嗜热栖热菌HB27在丰富培养基（嗜热栖热菌培养基）中进行分批培养，研究其生长动力学。生长速率和耗氧速率高度依赖于通气速率和搅拌速率。进入发酵液的体积传质系数（K(L)a，h⁻¹）以及因此的氧传递速率（OTR，mol m⁻³ h⁻¹）随着通气和/或搅拌速率的增加而增加。为避免氧限制，分别需要175.4 h⁻¹的K(L)a和31.7 mol m⁻³ h⁻¹的OTR，这对应于500 rpm的搅拌和2 vvm的通气（空气和氧气的混合物）。在这些条件下生长的嗜热栖热菌HB27的最大生长速率（μ(max)，h⁻¹）、倍增时间（t(D)，h）和干细胞重量分别为0.27 h⁻¹、2.67 h和3 g/l。该细胞产量高于之前发表的任何关于嗜热栖热菌培养生长的报告，包括使用加压生物反应器的研究。
