Dhouafli Zohra, Ben Jannet Hichem, Mahjoub Borhane, Leri Manuela, Guillard Jérôme, Saidani Tounsi Moufida, Stefani Massimo, Hayouni El Akrem
a Faculté des Sciences de Tunis , Université de Tunis El Manar , Tunis , Tunisia.
b Laboratoire des Plantes Aromatiques et Médicinales (LPAM- LR15CBBC06), Centre de Biotechnologie de Borj-Cédria , Hammam-Lif , Tunisia.
Nat Prod Res. 2019 May;33(10):1406-1414. doi: 10.1080/14786419.2017.1419229. Epub 2017 Dec 29.
Mounting evidence indicates free radicals as toxic species causing damage to human cells leading to the pathogenesis of many diseases such as neurodegenerative disease. Plant derived antioxidants are considered as promising strategy to prevent free radical toxicity. In this study, the crude extract (CE), 50%MeOH, Petroleum Ether (PE) and Ethyl acetate (EA) fractions of leaves were investigated for their antioxidant activity and their ability to counteract amyloid-β (Aβ) aggregation. Elution of the most bioactive fraction (EA) on silica gel column chromatography led to six sub-fractions. The most active sub-fraction (1) was further resolved on silica gel column chromatography. A new compound with powerful antioxidant and anti-Aβ aggregation properties was purified and characterised by spectroscopic methods as 1,2,4-trihydroxynaphthalene-2--β-D-glucopyranoside (THNG). This finding suggests that the antioxidant and anti-Aβ aggregation activities of leaves are strongly correlated to this compound.
越来越多的证据表明，自由基作为有毒物质会对人体细胞造成损害，导致许多疾病如神经退行性疾病的发病机制。植物来源的抗氧化剂被认为是预防自由基毒性的一种有前景的策略。在本研究中，对叶片的粗提物（CE）、50%甲醇、石油醚（PE）和乙酸乙酯（EA）馏分进行了抗氧化活性及其对抗淀粉样β蛋白（Aβ）聚集能力的研究。将生物活性最高的馏分（EA）在硅胶柱色谱上洗脱，得到六个亚馏分。活性最高的亚馏分（1）在硅胶柱色谱上进一步分离。通过光谱方法纯化并鉴定了一种具有强大抗氧化和抗Aβ聚集特性的新化合物，为1,2,4-三羟基萘-2--β-D-吡喃葡萄糖苷（THNG）。这一发现表明，叶片的抗氧化和抗Aβ聚集活性与该化合物密切相关。
