Bezzubov A A, Gessler N N
Prikl Biokhim Mikrobiol. 1977 Mar-Apr;13(2):301-9.
A quantitative gas-chromatographic method to assay S-methyl methionine (vitamin U) in plants has been developed. The method is based on the disintegration of S-methyl methionine in the alkaline medium to form equimolecular quantities of dimethyl sulphide and homoserine. Dimethyl sulphide is distilled in the flow of an inert gas (nitrogen) and trapped in the toluene trap cooled to--78 degrees. The toluene solution containing dimethyl sulphide and carbon tetrachloride as an inner reference is analyzed in a gas chromatograph. Optimal conditions for the reaction to form 91.1% dimethyl sulphide from S-methyl methionine sulphonium chloirde at concentrations ranging from 0.1--5.0 mg% have been established. The standard error of measurements is +/- 1.5%.
已开发出一种定量气相色谱法来测定植物中的S-甲基蛋氨酸（维生素U）。该方法基于S-甲基蛋氨酸在碱性介质中分解形成等摩尔量的二甲基硫和高丝氨酸。二甲基硫在惰性气体（氮气）流中蒸馏，并捕集在冷却至-78℃的甲苯阱中。含有二甲基硫和作为内标的四氯化碳的甲苯溶液在气相色谱仪中进行分析。已确定了在浓度范围为0.1-5.0mg%时由S-甲基蛋氨酸氯锍盐形成91.1%二甲基硫的反应的最佳条件。测量的标准误差为±1.5%。
