利用聚乙烯醇-海藻酸钙固定化Propionibacterium freudenreichii NX-4制备丙酸

PVA-calcium alginate immobilization with Propionibacterium freudenreichii NX-4 for propionic acid production

以Propionibacterium freudenreichii NX-4为研究对象,采用聚乙烯醇(PVA)和海藻酸钠互配作为固定化载体,考察了其制备丙酸的最佳固定化条件:ρ(PVA)为10.7 g/L,ρ(海藻酸钠)为1.4 g/L,包埋量16%(质量分数),ρ(硼酸)为50 g/L,固定化时间18 h.经15批次的发酵验证,产量稳定,丙酸平均产量为19.64 g/L(葡萄糖40 g/L).以80 g/L的葡萄糖为C源固定化制备丙酸192 h,丙酸产量达35.4 g/L.

Propionic acid was produced by polyvinyl alconhol （PVA） and calcium alginate immobilization with Propionibacteriumfreudenreichii NX-4 and embedding conditions were investigated. The results showed that the optimal concentration of PVA and sodium alginate was 10. 7 g/L and 1.4 g/L, respectively. The gel was immobilized in the stationary liquid including calcium chloride （2%） and boric acid （5%） for 18 h, and an efficient production of propionic acid was achieved. The production of propionic acid was about 19.64 g/L after 15 batches of fermentation （40 g/L of glucose）. After 192 h fermentation, the production of propionic acid reached 35.4 g/L with 80 g/L of glucose.