Aromatic and Medicinal Plants Unit, Biotechnological Center in Borj-Cedria Techno-park, 901 Hammam-Lif, Tunisia.
Phytochemistry. 2011 Nov;72(16):2031-6. doi: 10.1016/j.phytochem.2011.07.009. Epub 2011 Aug 16.
Withanolide-type steroids, withametelin Q (1) and 12α-hydroxydaturametelin B (2) along with three known withanolides, were isolated from leaves of Datura metel L. (Solanaceae). The respective structures, characterized mainly by NMR spectroscopy, were identified as (20R,22R,24R)-21,24-epoxy-1α,3β-dihydroxywitha-5,25(27)-dienolide-3-O-β-D-glucopyranoside (1) and (20R,22R,24R)-12α,21,27-trihydroxy-1-oxowitha-2,5,24-trienolide-27-O-β-D-glucopyranoside (2). The cytotoxicity of isolated compounds was evaluated against human lung carcinoma cells (A549) and human colorectal adenocarcinoma cells (DLD-1), respectively. Compound 2 exhibited cytotoxicity against A549 and DLD-1 cell lines, with IC50 values of 7 and 2.0 μM, respectively. However, for compounds 6 and 7, cytotoxicities were higher against DLD-1 cells with IC(50) values of 0.6 and 0.7 μM. Both compounds blocked the cell cycle in the S-phase and induced apoptosis.
从曼陀罗（茄科）的叶子中分离得到了 5 个甾体化合物，包括 withametelin Q（1）和 12α-羟基杜塔 metelin B（2）以及 3 个已知的 withanolides。主要通过 NMR 光谱学特征鉴定了它们的结构，分别为（20R,22R,24R）-21,24-环氧-1α,3β-二羟基 witha-5,25(27)-二烯醇-3-O-β-D-吡喃葡萄糖苷（1）和（20R,22R,24R）-12α,21,27-三羟基-1-氧代 witha-2,5,24-三烯醇-27-O-β-D-吡喃葡萄糖苷（2）。分别评估了分离得到的化合物对人肺癌细胞（A549）和人结肠直肠腺癌细胞（DLD-1）的细胞毒性。化合物 2 对 A549 和 DLD-1 细胞系表现出细胞毒性，IC50 值分别为 7 和 2.0 μM。然而，对于化合物 6 和 7，它们对 DLD-1 细胞的细胞毒性更高，IC50 值分别为 0.6 和 0.7 μM。这两种化合物都能阻断 S 期细胞周期并诱导细胞凋亡。
