真氧产碱杆菌利用混合有机酸生物合成聚羟基烷酸酯

研究了真氧产碱杆菌利用混合有机酸作为碳源进行聚羟基烷酸酯的生物合成.实验表明，在由乙酸、丙酸、乳酸、丁酸组成的混合酸中，各有机酸在细胞生长以及聚羟基烷酸酯的合成过程中所起的作用各不相同.另外，通过5 L罐进行的分批以及流加发酵实验证实，流加发酵，特别是经优化后的流加发酵，可以获得更高的细胞干质以及PHAs产量，但聚合物中聚羟基戊酸酯组分的比例明显低于分批发酵.

BIOSYNTHESIS OF POLYHYDROXYALKANOATES BY Ralstonia eutropha WITH MIXED ORGANIC ACIDS AS CARBON SOURCE

Different proportions of mixed organic acids containing acetic acid, propionic acid, lactic acid and butyric acid were used as carbon source for biosynthesis of polyhydroxyalkanoates by Ralstonia eutropha The utilization of four acids for cell growth and PHAs biosynthesis were investigated In contrast with batch culture, fed batch, especially the optimized fed batch was more efficient in the cell growth and PHAs biosynthesis However, the yield of hydroxyvalerate from propionic acid by fed batch is markedly lower than that of the batch culture, for more propionic acid was used for the synthesis of cell components and hydroxybutyrate unit than hydroxyvalerate unit of the polyhydroxalkanoates when propionic acid was continuously fed