一株快速生长酯化菌的酯化方式

Esterification Way of an Esterying Strain with High Growing—up Speed

采用常规诱变选育方法获得的RH304菌株,具有酯化活力强、培养温度低、生长迅速等优点。RH304菌株从固态发酵和液态发酵获得的菌体细胞,以及从液体发酵液获得的沉降酶,均具有很高的己酸乙酯酯化能力。但固体培养物重复使用寿命低于液体培养物,用海藻酸钠和PVA包埋固定化菌体和孢子,其酯化活性也低于处理后全细胞。全细胞在有机相中催化己酸乙酯合成,连续使用8次酯化率维持在95%以上。在无溶剂相酯化系统中,经1月反应酯化率为70%左右,己酸乙酯生成量可达50～70 g/L.

RH304 strain with high esterification activity, lower cultivating temperiture, quickly growing up and other advantages was gained by usual mutation and screening methods. The cell from the solid state fermentation and liquid fermentation of RH304 strain and subsidence enzyme from fermenting liquor, both had high ability of esterifying into acetic ether. However, the solid cultivation had a shorter life than liquid cultivation during repeatedly using. The esterification activity of cell and spore wrapped by sodium alginate and PVA was lower than the whole cell after treatment. The esterifying ratio of synthesizing acetic ether catalysised by the whole cell in organic phase kept more than 95%. It was about 70% after one month reaction in the inorganic phase, and the producing quantity of acetic ether was 50 ～70 g/L.