固定化细胞法生产醋酸的工艺研究

论文编号:HG238  论文字数:13541,页数:24

摘要：目前对于细胞固定化的动力学研究，工业上生产大多以专家经验为主，对其深入的探讨不是很多，由于固定化细胞的优势在未来的工业生产和研究方面会有越来越重要的地位。本论文设计了固定化细胞法生产醋酸的工艺，用海藻酸钠包埋法制备了平均直径为 5.0mm的固定化醋酸菌颗粒，将制得的固定化颗粒放入发酵培养基中培养，对菌种扩大培养的条件进行了优化，获得最佳接种量为15环，最佳培养时间为43h。研究了葡萄糖浓度与葡萄糖OD值的关系，得到其标准曲线为：y=0.2117x；研究了菌体浓度于细胞OD值的关系，得到其标准曲线为：y =447.55x-44.161。研究了不同乙醇初始浓度下固定化醋酸菌的生长动力学，基质消耗动力学和产物生成动力学。研究了乙醇初始浓度的变化对菌体生长的影响：随着乙醇浓度的增加菌体的延滞期会延长。获得固定化细胞法生产醋酸的最佳发酵时间为96h。
 关键词：固定化细胞；动力学模型；醋酸菌；生长动力学；发酵

Abstract: At Present, study on the bioreactor system was focused on macro-dynamics. A lot of research has been done to the dynamics of immobilized enzyme, however, study on dynamics of immobilized cells remained low level. Actually, industrial production was charged with experience of the experts. For the immobilized cells has comparative advantage, which will play more and more important part in industrial production and academic research in future, a new acetic acid production process was designed in this paper. Immobilized cells were main used in the Craft. Immobilized acetic acid bacteria was prepared by calcium alginate embedding, the average diameter of immobilized cell of 5.0 mm was obtained. The best Strain expanding condition was measured : vaccination 15 rings and cultivate 43 hours. The standard curve of glucose (OD540) was measured : y=0.2117x; and the standard curve of the bacterial cell (OD) was measured: y=402.88x. growth curve of the immobilized acetic acid bacteria basis on different alcohol concentrations and the relational curve between substrate consumption (ethanol and glucose) and production (acetic acid) have been measured. As initial concentration of ethanol changes, the acid production and the bacteria growth would be impacted: acid production was effected when alcohol concentration was too high or too low. As the concentration of ethanol increasing, bacteria for the extension of demurrage will be extended. The range of suitable initial ethanol concentration was 4% to 8%, and best fermentation time were 96 hours.
 Key words: Immobilized cells；dynamic model；acetic acid bacteria； the growth curve； fermentation

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