石菖蒲中乙酰胆碱酯酶抑制剂的筛选

Screening of acetylcholinesterase inhibitors in root of Acorus tatarinowii

目的从石菖蒲中筛选天然乙酰胆碱酯酶(AChE)抑制剂。方法采用高效薄层色谱(HPTLC)-生物自显影,筛选石菖蒲提取物和固相萃取小柱分段部位的乙酰胆碱酯酶抑制斑点并定位,采用薄层色谱-质谱(TLC-MS)分析薄层板上的目标物并获取分子量和碎片信息,结合文献数据鉴定化合物,并采用分子对接技术测算化合物与AChE蛋白的亲和力以及结合方式,验证其活性。结果从石菖蒲提取物中共发现5个活性斑点,薄层色谱-质谱鉴定出4个斑点可能为β-细辛醚(与α-细辛醚斑点重合)、亚油酸、菖蒲螺酮烯和桔利酮,其中β-细辛醚、α-细辛醚和亚油酸与对照品对照得到验证。分子对接结果显示,5个化合物与AChE分子具有较好的结合能力,可能是通过TRP86、TRP337和PHE338等氨基酸与乙酰胆碱酯酶产生氢键作用或疏水作用。结论菖蒲螺酮烯、桔利酮、β-细辛醚、α-细辛醚和亚油酸为石菖蒲中主要乙酰胆碱酯酶抑制活性成分。

AIM To screen natural acetylcholinesterase(AChE)inhibitors from the root of Acorus tatarinowii Schott.METHODS Anti-AChE constituents from the root extract of A.tatarinowii screened by High-performance thin-layer chromatogrophy(HPTLC)-bioautography had their structures analyzed and identified by the electrospray ionization-mass spectrometry linked with TLC-MS interface;and their activities verified via investigation of their binding energy and the interactive mechanism of the target constituents with AChE by molecular simulation.RESULTS Among the five zones for active AChE inhibitors,four constituents including acorenone,zierone,β-asarone(presenting the same R_(F) value and similar features withα-asarone),and linoleic acid were screened and identified based on molecular mass and fragment ions by HPTLC-MS analysis,and verified by reference substances partly.Molecular docking revealed the five compounds’good binding abilities with the protein receptor,and their possible hydrogen bonding or hydrophobic interaction with AChE through amino acids such as TRP86,TRP337 and PHE338.CONCLUSION Acorenone,zierone,β-asarone,α-asarone and linoleic acid are the active AChE inhibitors in the root extract of A.tatarinowii.