衍生化GC法测定生物转化产品L-山梨糖及其中残余D-山梨醇的含量

DETERMINATION OF LSORBOSE PREPARED BY BIOCONVERSIONAND RESIDUAL DSORBITOL IN IT BY DERIVATIVE GC METHOD

设计了生物转化产品Ｌ山梨糖及其中残余Ｄ山梨醇的衍生化ＧＣ测定方法。以乙酸酐—吡啶（１∶１）为衍生化试剂对样品中残余Ｄ山梨醇进行乙酰化ＧＣ测定，再以四氢硼钠为还原剂、乙酸酐为乙酰化试剂对样品中Ｌ山梨糖进行还原乙酰化ＧＣ测定。结果表明，Ｄ山梨醇及Ｌ山梨糖分别在００１９９９～２９９９μｇ及４００～２４００μｇ范围内呈线性。本法精密度及回收率均较好，可用于监测Ｌ山梨糖生物转化终点及其成品中Ｌ山梨糖及残余Ｄ山梨醇的含量。

A derivative GC method with ntetracosane as the internal standard was developed for the determination of Lsorbose prepared by bioconversion and residual Dsorbitol in it. The method includes two procedures. The first procedure involves acetylation of bioconversion samples with a solution of acetic anhydride: pyridine(1∶1) at 90℃ for 20 min. The resulting products were assayed by GC to determine residual Dsorbitol. The second procedure involves reduction of the bioconversion samples with NaBH4 in aqueous solution at 40℃ for 1 hour followed by reaction with the mixture of acetic anhydride: pyridine(1∶1) at 90℃ for 20 min. The resulting products were assayed by GC to determine Lsorbose. Chromatography was performed on a 5% OV17 stainless steel column(2 m×3 mm ID) with nitrogen as carrier gas. The detector was FID. The standard curves of Dsorbitol and Lsorbose were linear in the ranges of 001999～2999 μg and 4000～24000 μg respectively. The method has been applied to assay Lsorbose and residual Dsorbitol in bioconversion products and to monitor bioconversion termination point of Lsorbose.