关键词:

乳化-内部凝胶化, 海藻酸钠, 微生物, 固定化培养

Abstract:

The emulsification-internal gelation technology has attracted considerable interest in scale-up preparation of calcium alginate gel beads with controllable size and uniform size distribution, and has been used as controlled release carriers of enzymes, proteins and poly-peptide drugs and in immobilization of enzymes. In this paper, the idea of preparing immobilization carrier of microbes using the emulsification-internal gelation technology was put forward with S. cerevisiae BY4741 (yeast cells) as a model. The influence of process parameters on the survival rate of microbes was firstly evaluated, which showed that acetic acid was harmful to yeast cells. Based on the mechanism analysis of internal gelation, the process parameters were adjusted and improved to benefit the survival and growth of microbes. As a result, the survival rate of yeast cells could reach 77.0%, and the volumetric yield rate of gel beads was 93.5%. Furthermore, alginate-chitosan (AC) microcapsules entrapping yeast cells were prepared, and the growth kinetics of AC microencapsulated yeast cells was investigated. The results showed that AC microcapsules kept intact with the immobilized culture process, and the growth kinetics of AC microencapsulated cells was better than that of free culture. Therefore, the emulsification-internal gelation technology is expected to be used for the scale-up production of high-value drugs or fine chemicals with immobilized culture of microbes.

Key words:

乳化-内部凝胶化, 海藻酸钠, 微生物, 固定化培养