Bäckermann S, Poel C, Ternes W
Center for Food Sciences, Institute for Food Toxicology and Chemical Analytics, University of Veterinary Medicine Hannover, Bischofsholer Damm 15/123, D-30173, Hannover, Germany.
Poult Sci. 2008 Jan;87(1):108-15. doi: 10.3382/ps.2007-00158.
The thiamin (TH), thiamin monophosphate (TMP), thiamin diphosphate (TDP), and thiamin triphosphate (TTP) content was analyzed in yolk plasma and yolk granules of unincubated and incubated chicken eggs and in 5- and 7-day-old chick embryos. Analytes were extracted from samples weighing approximately 1 g, with trichloroacetic acid (0.4 g/L), isolated with solid-phase extraction, and determined with HPLC. Before solid-phase extraction with a C-18 cartridge and a strong anion exchange cartridge, analytes were converted to thiochromes with cyanogen bromide. For HPLC, a C-8 pre-column and a C-8 column connected to a NH(2) column were used with a fluorescence detector. No thiamin phosphates were found in egg yolk plasma or granules in native and embryonated eggs. The TH content in DM was 3,400 +/- 700 ng/g for yolk plasma, 1,500 +/- 140 ng/g for yolk granules of unincubated eggs, and 4,400 +/- 1,100 ng/g for yolk plasma and 2,100 +/- 450 ng/g for yolk granules of 5-d embryonated eggs. In chick embryos, TH as well as thiamin phosphates were found. The mean content in 5-d-old embryos was 1,200 +/- 400 ng of TH and 8,000 +/- 1,000 ng of TDP/g of DM. In 7-d-old embryos, the content of TH was 900 +/- 200 ng, TMP was 400 +/- 200 ng, and TDP was 5,500 +/- 1,300 ng/g of DM. Thiamin triphosphate was not detected, and the minimum detectable limit for T was 0.3 ng/mL, for TMP 0.5 ng/mL, and for TDP 0.9 ng/mL, respectively. Recovery was 71% for TMP and 64% TDP in plasma and 58% TMP and 47% TDP in granules. It was demonstrated that only TH is present in egg yolk fractions in native and embryonated eggs of hens and that thiamin phosphates can be found in 5- and 7-d-old embryos, which indicates that they are synthesized by the chick embryo. According to its assumed unique role in highly specialized tissues, TTP was not found in early embryos.
分析了未孵化和已孵化鸡蛋的卵黄血浆和卵黄颗粒以及5日龄和7日龄鸡胚中的硫胺素（TH）、硫胺素单磷酸酯（TMP）、硫胺素二磷酸酯（TDP）和硫胺素三磷酸酯（TTP）含量。用三氯乙酸（0.4 g/L）从约1 g重的样品中提取分析物，通过固相萃取进行分离，并用高效液相色谱法进行测定。在用C-18柱和强阴离子交换柱进行固相萃取之前，用溴化氰将分析物转化为硫色素。对于高效液相色谱法，使用连接到NH(2)柱的C-8预柱和C-8柱以及荧光检测器。在未孵化和已孵化鸡蛋的卵黄血浆或颗粒中未发现硫胺素磷酸盐。未孵化鸡蛋的卵黄血浆中DM的TH含量为3400±700 ng/g，卵黄颗粒中为1500±140 ng/g；5日龄已孵化鸡蛋的卵黄血浆中为4400±1100 ng/g，卵黄颗粒中为2100±450 ng/g。在鸡胚中，发现了TH以及硫胺素磷酸盐。5日龄胚胎中TH的平均含量为1200±400 ng，TDP为8000±1000 ng/g DM。在7日龄胚胎中，TH含量为900±200 ng，TMP为400±200 ng，TDP为5500±1300 ng/g DM。未检测到硫胺素三磷酸酯，T的最低检测限分别为0.3 ng/mL，TMP为0.5 ng/mL，TDP为0.9 ng/mL。血浆中TMP的回收率为71%），TDP为64%；颗粒中TMP为58%，TDP为47%。结果表明，母鸡未孵化和已孵化鸡蛋的卵黄部分中仅存在TH，而在5日龄和7日龄胚胎中可发现硫胺素磷酸盐，这表明它们是由鸡胚合成的。根据其在高度特化组织中假定的独特作用，在早期胚胎中未发现TTP。
