为提高丙酸发酵效率，进行了固定化费氏丙酸菌发酵丙酸的研究．采取吸附-包埋结合法，先以麸皮进行吸附，再用海藻酸钠-聚乙烯醇进行包埋制备固定化细胞．通过正交实验确定了固定化细胞的工艺条件：菌液与麸皮比例为5,mL∶0.6,g，吸附时间为15,min，包埋剂选用海藻酸钠和聚乙烯醇混合物，质量比为3∶3，此条件下的包埋效率达到96.86%．初步研究了碳源及其质量浓度对固定化细胞生产丙酸的影响，确定了以乳酸钠为碳源，质量浓度为40,g/L，丙酸产量可达13.75,g/L．%In order to improve the efficiency of propionic acid fermentation,propionic acid fermentation with immobilized Propionibacterium freudenreichii were investigated. Adsorption-entrapping method was used to prepare immobilized cells with bran as the adsorbent and CA-PVA as the entrapping material. Through orthogonal experiment,the propionic acid im-mobilized cells’ fermentation process conditions were determined. The proportion of bacterium solution to bran was 5,mL∶0.6 g,the adsorption time was 15,min,the entrapping agent was the mixture of CA and PVA,the mass ratio was 3∶3. Under this immobilization conditions,the encapsulation efficiency reached 96.86%. The effect of the carbon sources and their con-centration on propionic acid production were investigated. The experimental results showed that the sodium lactate was a better carbon source.When the sodium lactate concentration was 40,g/L,the yield of propionic acid reached 13.75,g/L.
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