School of Pharmaceutical Sciences, Universiti Sains Malaysia, 11800 Minden, Malaysia.
USM-RIKEN Centre for Aging Science (URICAS), Universiti Sains Malaysia, 11800 Minden, Malaysia.
Molecules. 2020 Oct 4;25(19):4545. doi: 10.3390/molecules25194545.
Seventeen methanol extracts from different plant parts of five different species, including , , , , and were screened against acetylcholinesterase (AChE). extracts were found to exhibit the highest inhibition towards AChE whereby the leaf, stem, and flower methanol extracts showed 94-97% inhibition. As far as we are aware, is one of the least explored spp. for bioactivity. Further fractionation led to the identification of six compounds, isolated for the first time from : 3-methoxyquercetin (), benzenepropanoic acid (), 9,12,15-octadecatrienoic acid (), β-sitosterol (), stigmasterol (), and 1-octadecanol (). Compound showed moderate inhibition towards AChE (IC: 83.71 μM), while the other compounds exhibited poor to slightly moderate AChE inhibitory activity. Molecular docking revealed that the methoxy substitution of formed a hydrogen bond with TYR121 at the peripheral anionic site (PAS) and the hydroxyl group at C5 formed a covalent hydrogen bond with ASP72. Additionally, the OH group at the C3' position formed an interaction with the protein at the acyl pocket (PHE288). This possibly explains the activity of in blocking the entry of acetylcholine (ACh, the neurotransmitter), thus impeding the hydrolysis of ACh.
从五个不同物种的 17 种不同植物部位的甲醇提取物中筛选出对乙酰胆碱酯酶（AChE）具有抑制作用的提取物。其中，叶子、茎和花的甲醇提取物对 AChE 的抑制作用最高，达到 94-97%。据我们所知，是生物活性研究最少的 spp. 之一。进一步的分离导致鉴定出 6 种化合物，这是首次从 中分离出来的：3-甲氧基槲皮素（）、苯丙酸（）、9,12,15-十八碳三烯酸（）、β-谷甾醇（）、豆甾醇（）和 1-十八烷醇（）。化合物 对 AChE 表现出中等抑制作用（IC：83.71 μM），而其他化合物对 AChE 表现出较差到中等适度的抑制活性。分子对接表明，的甲氧基取代基与外周阴离子部位（PAS）的 TYR121 形成氢键，C5 上的羟基与 ASP72 形成共价氢键。此外，C3' 位置的 OH 基团与酰基口袋（PHE288）中的蛋白质形成相互作用。这可能解释了 阻止乙酰胆碱（ACh，神经递质）进入的活性，从而阻碍 ACh 的水解。
