乌头碱的代谢产物去氧乌头碱的生物转化及其电喷雾串联质谱

采用人肠内细菌和乌头碱体外温孵的方法, 探讨去氧乌头碱在人肠内的生物转化. 利用离子阱和傅里叶变换离子回旋共振质谱直接分析去氧乌头碱的转化产物. 乌头类生物碱及其代谢产物在正离子电喷雾质谱条件下形成质子化分子(M+H]+), 通过多级串联质谱进行结构表征. 去氧乌头碱可被人肠内细菌转化, 通过脱酰基、脱甲基脱羟基以及酯化反应产生新型的单酯型、双酯型和脂类生物碱等10余种代谢产物. 双酯型的去氧乌头碱的毒性较高, 当它被肠内细菌转化为单酯型和脂类生物碱时会使其毒性降低.

Biotransformation of Deoxyaconitine of Metabolite of Aconitine by Human Intestinal Bacteria and Electrospray Ionization Tandem Mass Spectrometry

To study the biotransformation of deoxyaconitine in intestine, aconitine was incubated with human intestinal bacteria in vitro. The metabolites of deoxyaconitine were investigated by ion trap and Fourier transform ion cyclotron resonance electrospray ionization tandem mass spectrometry directly. Aconitine and its metabolites formed the protonated molecular ion M H] in the positive ion mode. According to the m/z of M H] , the molecular weight of the metabolite was determined and the structure was characterized by using MSn and the data in literature. The results show that deoxyaconitine could be transformed by human intestinal bacteria. Deoxyaconitine was converted into more than ten kinds of new metabolites such as mono-ester aconitum alkaloids, diester aconitines and lipo-alkaloids by deacetylation, debenzoylation, dehydroxylation, demethylation and esterification. Diester deoxyaconitine is very toxic. When deoxyaconitine was transformed into mono-ester aconitum alkaloids and lipo-alkaloids by human intestinal bacteria, the toxicity decreased.