Chemical study of Adenocalymma axillarum crude leaf extract and isolated compounds

Abstract Adenocalymma axillarum (K.Schum.) L.G. Lohmann is a liana belonging to the family Bignoniaceae. In traditional medicine, the genus Adenocalymma is used to treat fever, skin ailments, and body, joint, and facial muscle pains, and it is also applied as cosmetic. Biological assays conducted with the A. axillarum crude leaf ethanol extract have indicated leishmanicidal activity and absence of cytotoxicity. This study aimed to analyze the A. axillarum leaf ethanol crude extract by high-performance liquid chromatography-high-resolution mass spectrometry- diode array detector (HPLC-HRMS-DAD) and to evaluate the leishmanicidal and cytotoxic activities of this crude extract, its fractions, and isolated compounds. HPLC-HRMS-DAD analysis of this extract revealed that it consisted mainly of flavonoids, with nine major compounds. Extract purification yielded 4-hydroxy-N-methylproline, 6-β-hydroxyipolamiide, quercetin-3-O-robinobioside, hyperin, isorhamnetin-3-O-robinobioside, and 3’-O-methylhyperin, which were identified by Nuclear Magnetic Resonance. The isolated compounds were inactive against Leishmania amazonensis promastigotes and human lung fibroblast cells.

摘要 腋花腺萼藤（Adenocalymma axillarum (K.Schum.) L.G. Lohmann）是隶属于紫葳科（Bignoniaceae）的木质藤本植物。在传统医学应用中，腺萼藤属（Adenocalymma）植物可用于治疗发热、皮肤病症，以及躯体、关节与面部肌肉疼痛，同时还可作为化妆品使用。针对腋花腺萼藤叶片粗乙醇提取物开展的生物学实验显示，其具备抗利什曼虫活性，且无细胞毒性。本研究旨在通过高效液相色谱-高分辨质谱-二极管阵列检测器（high-performance liquid chromatography-high-resolution mass spectrometry-diode array detector, HPLC-HRMS-DAD）对该叶片粗乙醇提取物进行分析，并评价该粗提取物、其分级组分以及分离得到的单体化合物的抗利什曼虫活性与细胞毒性。经HPLC-HRMS-DAD分析发现，该提取物的主要成分为黄酮类化合物，共包含9种主要化合物。通过分离纯化，本研究得到了4-羟基-N-甲基脯氨酸、6-β-羟基伊波米苷、槲皮素-3-O-刺槐二糖苷、金丝桃苷、异鼠李素-3-O-刺槐二糖苷以及3’-O-甲基金丝桃苷，上述化合物均通过核磁共振（Nuclear Magnetic Resonance, NMR）技术完成结构鉴定。实验结果表明，所分离得到的单体化合物对亚马逊利什曼虫前鞭毛体以及人肺成纤维细胞均无活性。