利用甲烷氧化菌Methylosinus trichosporium OB3b生产四氢嘧啶的研究

A preliminary study on the production of ectoine by Methylosinus trichosporium OB3b

在盐浓度为0.03%(最适生长盐浓度)条件下培养甲基弯菌Methylosinus trichosporium OB3b,选用有机溶剂法提取胞内与胞外的四氢嘧啶,选用紫外-可见光谱、薄层色谱、红外色谱定性分析和高效液相色谱进行定量检测。结果表明,甲基弯菌OB3b在最适盐浓度下可以合成并分泌四氢嘧啶,平均产量为(84.9±5.49)mg/(g·d),最大产量为139.75 mg/(g·d)。该产量略高于目前国际上经常报道的甲烷氧化菌Methylomicrobium alcaliphilum 20Z合成四氢嘧啶的产量。虽然甲烷氧化菌合成四氢嘧啶的产量低于目前工业所使用菌株,但其可用以甲烷为唯一碳源的无机盐液体培养基培养,在较低盐条件下合成四氢嘧啶,分离纯化容易,经济价值高。

The salt concentration of 0.03%(the optimal growth salt concentration)was used under the condition of cultivation of Methylosinus trichosporium OB3b.Organic solvent has been used to extract ectoine in intracellular and extracellular from Methylosinus trichosporium OB3b.UV-visible spectrum(UV-Vis),thin-layer chromatography(TLC)and infrared spectrum were used to analyze the sample qualitatively.High performance liquid chromatography(HPLC)was used to analyze the sample quantitatively.The results showed that Methylosinus trichosporium OB3b could synthesize ectoine under the optimum salt concentration with the average yield of(84.9±5.49)mg/(g·d)and the maximum yield of 139.75 mg/(g·d),which is slightly higher than that of Methylomicrobium alcaliphilum 20Z that was frequently reported internationally.Although the yield of ectoine synthesized by moderate halophile Methylosinus trichosporium OB3b lower than that of hyperhalophilic strains currently used in industry,Methylosinus trichosporium OB3b can synthesize ectoine under lower salt conditions by using methane as its sole carbon source and inorganic salt as growth medium,which demonstrate the advantages of easy separation and high application value.