Abstract:
Lippia alba (Mill.) N.E. Brown (Verbenaceae), popularly known as \"erva cidreira\", is one of the most used plants in Brazilian folk medicine. The species has several chemotypes and its volatile constituents have already been characterized, and present different chemical markers with known pharmacological properties, such as analgesic, sedative and antifungal properties. The objective of this study was to evaluate the anticholinesterase activity (AChE) of the essential oil of three chemotypes of Lippia alba and, by using molecular anchoring, determine the best receptor-ligand interaction energies of the main constituents present in the samples of oil. The essential oils were obtained via hydrodistillation (LA1 and LA2) and steam drag (LA3), and their volatile constituents determined using GC-MS. For the determination of anticholinesterase activity, direct bioautography and colorimetry assays based on Ellman\'s method were used. Molecular docking was performed using a multiple solution genetic algorithm and Merck molecular force field 94 (MMFF94) as the scoring function. In the main constituents of the oil samples, three chemotypes were identified for L. alba: LA1 is rich in citral, LA2 is rich in carvone and LA3 is rich in linalool. All L. alba chemotypes showed AChE enzyme inhibition with an IC50 of 3.57 μg/mL (LA1), 0.1 μg/mL (LA2) and 4.34 μg/mL (LA3). The molecular docking study complemented the results of the experiment and demonstrated significant interactions between the main constituents of the oils and the amino acid residues of the AChE enzyme. Irrespective of the chemotype, Lippia alba presents biotechnological potential for the discovery of anticholinesterase substances, with the chemotype LA2 (rich in carvone) being the most active.
摘要:
Lippiaalba(磨坊。)N.E.布朗(马鞭草科),俗称“埃尔瓦·西德雷拉”,是巴西民间医学中最常用的植物之一。该物种具有几种化学类型,其挥发性成分已经被表征,并呈现具有已知药理特性的不同化学标记,如镇痛药,镇静和抗真菌特性。这项研究的目的是评估三种化学型Lippiaalba精油的抗胆碱酯酶活性(AChE),通过使用分子锚定,确定油样品中主要成分的最佳受体-配体相互作用能。精油是通过加氢蒸馏(LA1和LA2)和蒸汽阻力(LA3)获得的,以及使用GC-MS测定的挥发性成分。为了测定抗胆碱酯酶活性,使用基于Ellman方法的直接生物自显影和比色法测定。使用多解遗传算法和Merck分子力场94(MMFF94)作为评分函数进行分子对接。在油样的主要成分中,对L.alba鉴定了三种化学类型:LA1富含柠檬醛,LA2富含香芹酮,LA3富含芳樟醇。所有L.alba化学型显示AChE酶抑制,IC50为3.57μg/mL(LA1),0.1μg/mL(LA2)和4.34μg/mL(LA3)。分子对接研究补充了实验结果,并证明了油的主要成分与AChE酶的氨基酸残基之间的显着相互作用。不管化学类型,Lippiaalba提出了发现抗胆碱酯酶物质的生物技术潜力,化学型LA2(富含香芹酮)最活跃。