Bioprocess Engineering Laboratory, Department of Biotechnology, Indian Institute of Technology, Roorkee, India.
Bioresour Technol. 2012 Apr;109:131-9. doi: 10.1016/j.biortech.2012.01.039. Epub 2012 Jan 20.
Recently suitability of crude glycerol for trehalose and propionic acid productions was reported using Propionibacterium freudenreichii subspp. shermanii and it was concluded that presence of KCl in crude glycerol was the probable reason for higher trehalose accumulation with crude glycerol medium. To further improve trehalose production, an osmotic sensitive mutant of this strain (non-viable in medium with 3% NaCl) with higher trehalose yield was isolated. In mutant, trehalose yields achieved with respect to biomass and substrate consumed (391 mg/g of biomass, 90 mg/g of substrate consumed) were three and four times higher, respectively as compared to parent strain when crude glycerol was used as a carbon source. Other major fermentation products obtained were propionic acid (0.42 g/g of substrate consumed) and lactic acid (0.3g/g of substrate consumed). It was also observed that in mutant higher activity of ADP-glucose pyrophosphorylase was probably responsible for higher trehalose accumulation.
最近有报道称，粗甘油可用于生产海藻糖和丙酸，使用丙酸弗雷登斯氏菌亚种。谢尔曼和得出的结论是，粗甘油中存在 KCl 是导致粗甘油培养基中海藻糖积累更高的可能原因。为了进一步提高海藻糖的产量，从该菌株中分离出了一种对渗透压敏感的突变体（在含有 3%NaCl 的培养基中不可存活），该突变体的海藻糖产量更高。与亲本菌株相比，当使用粗甘油作为碳源时，突变体的海藻糖产量相对于生物质和消耗的底物分别提高了 3 倍和 4 倍（391mg/g 生物质，90mg/g 消耗的底物）。获得的其他主要发酵产物是丙酸（0.42g/g 消耗的底物）和乳酸（0.3g/g 消耗的底物）。还观察到，在突变体中，较高的 ADP-葡萄糖焦磷酸化酶活性可能是导致海藻糖积累较高的原因。
