LC-MSn characterization of steroidal saponins in Helleborus niger L. roots and their conversion products during fermentation
LC-MSn characterization of steroidal saponins in Helleborus niger L. roots and their conversion products during fermentation
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DOI：
10.1016/j.steroids.2014.09.011
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发表时间：
2015-01-01
期刊：
影响因子：
2.7
通讯作者：
Stintzing, Florian C.
中科院分区：
文献类型：
--
作者：
Duckstein, Sarina M.;Stintzing, Florian C.
甾体皂苷是药用植物铁筷子（Helleborus尼日尔L.）次生代谢产物的重要组成部分。（black hellebore）.通过LC-MSn研究来自根的皂苷级分，得到38种皂苷和β-蜕皮激素。9个薯蓣皂苷基型糖苷，主要是呋甾组成的苷元薯蓣皂苷元，macranthogenin，sceptumgenin，和sarsasapogenin伴随着5个薯蓣皂苷基型皂苷表现出一个苷元与一个额外的OH基团。然而，最相关的化合物是24个乙酰化的多羟基皂苷，包括hellebosaponins A和D。酶葡萄糖醛酸酶，β-葡萄糖苷酶，和果胶酶被用来获得一个想法的潜在发酵转化反应，通过孵育分离的模型皂苷macranthoside I和hellebosaponin A。在第二步中，将H.在发酵和12个月的储存期间监测含有更大范围的皂苷的尼日尔提取物。通过LC-MSn和靶向提取离子电流（EIC）扫描分析检查并分配代谢产物。模型化合物的测定结果与整个水发酵提取物的测定结果吻合较好，天然薯蓣皂苷类呋甾皂苷在己糖的断裂作用下转化为螺甾醇。乙酰化的多羟基皂苷，专门螺甾烷醇的改变发生在乙酰基和末端脱氧己糖裂解后。最有趣的是，糖链C（1）处的戊糖不受影响。乙酰化的多羟基皂苷的转化导致最终的结构类型，即使在发酵和储存12个月后，该结构类型也是稳定的和可检测的。(C)2014 Elsevier Inc. All rights reserved.
Steroidal saponins comprise a substantial part of the secondary metabolite spectrum in the medicinal plant Helleborus niger L. (black hellebore). The saponin fraction from the roots was investigated by LC-MSn resulting in 38 saponins and beta-ecdysone. Nine diosgenyl-type glycosides, mainly furostanols consisting of the aglycones diosgenin, macranthogenin, sceptrumgenin, and sarsasapogenin were accompanied by 5 diosgenyl-type saponins exhibiting an aglycone with an additional OH group. However, the most relevant compounds were 24 acetylated polyhydroxy saponins including hellebosaponins A and D.The enzymes glucuronidase, beta-glucosidase, and pectinase were used to obtain an idea on potential fermentative transformation reactions by incubation of the isolated model saponins macranthosid I and hellebosaponin A. In a second step, aqueous H. niger extracts containing a much greater range of saponins were monitored during fermentation and 12 months of storage. The metabolites were examined and assigned by LC-MSn and targeted extracted ion current (EIC) scan analyses. Good agreement was found among the results from the model compounds and the whole aqueous fermented extracts.The native diosgenyl-type furostanol saponins were converted to spirostanols under scission of hexoses. Alteration of the acetylated polyhydroxy saponins, exclusively spirostanols, took place following cleavage of acetyl groups and terminal deoxyhexoses. Most interestingly, the pentoses of the sugar chain at C(1) were not affected. Conversion of acetylated polyhydroxy saponins resulted in a final structure type which was stable and detectable, even after 12 months of fermentation and storage. (C) 2014 Elsevier Inc. All rights reserved.