Nejatzadeh-Barandozi Fatemeh
Department of Horticulture, Faculty of Agriculture, Khoy Branch, Islamic Azad University, P,O, Box 58168-44799, Khoy, Iran.
Org Med Chem Lett. 2013 Jul 19;3(1):5. doi: 10.1186/2191-2858-3-5.
The aim of this study was to identify, quantify, and compare the phytochemical contents, antioxidant capacities, and antibacterial activities of Aloe vera lyophilized leaf gel (LGE) and 95% ethanol leaf gel extracts (ELGE) using GC-MS and spectrophotometric methods.
Analytically, 95% ethanol is less effective than ethyl acetate/diethyl ether or hexane (in the case of fatty acids) extractions in separating phytochemicals for characterization purposes. However, although fewer compounds are extracted in the ELGE, they are approximately 345 times more concentrated as compared to the LGE, hence justifying ELGE use in biological efficacy studies in vivo. Individual phytochemicals identified included various phenolic acids/polyphenols, phytosterols, fatty acids, indoles, alkanes, pyrimidines, alkaloids, organic acids, aldehydes, dicarboxylic acids, ketones, and alcohols. Due to the presence of the antioxidant polyphenols, indoles, and alkaloids, the A. vera leaf gel shows antioxidant capacity as confirmed by ORAC and FRAP analyses. Both analytical methods used show the non-flavonoid polyphenols to contribute to the majority of the total polyphenol content. Three different solvents such as aqueous, ethanol, and acetone were used to extract the bioactive compounds from the leaves of A. vera to screen the antibacterial activity selected human clinical pathogens by agar diffusion method. The maximum antibacterial activities were observed in acetone extracts (12 ± 0.45, 20 ± 0.35, 20 ± 0.57, and 15 ± 0.38 nm) other than aqueous and ethanol extracts.
Due to its phytochemical composition, A. vera leaf gel may show promise in alleviating symptoms associated with/or prevention of cardiovascular diseases, cancer, neurodegeneration, and diabetes.
本研究的目的是使用气相色谱 - 质谱联用（GC - MS）和分光光度法鉴定、定量并比较库拉索芦荟冻干叶凝胶（LGE）和95%乙醇叶凝胶提取物（ELGE）的植物化学成分、抗氧化能力和抗菌活性。
从分析角度来看，在分离用于表征目的的植物化学成分时，95%乙醇在提取效果上不如乙酸乙酯/乙醚或己烷（对于脂肪酸而言）。然而，尽管ELGE中提取的化合物较少，但与LGE相比，其浓度大约高345倍，因此证明ELGE可用于体内生物学功效研究。鉴定出的个别植物化学成分包括各种酚酸/多酚、植物甾醇、脂肪酸、吲哚、烷烃、嘧啶、生物碱、有机酸、醛、二羧酸、酮和醇。由于存在抗氧化多酚、吲哚和生物碱，经氧自由基吸收能力（ORAC）和铁离子还原抗氧化能力（FRAP）分析证实，库拉索芦荟叶凝胶具有抗氧化能力。所使用的两种分析方法均表明，非黄酮类多酚占总多酚含量的大部分。使用水、乙醇和丙酮三种不同溶剂从库拉索芦荟叶中提取生物活性化合物，通过琼脂扩散法筛选对选定人类临床病原体的抗菌活性。除水提取物和乙醇提取物外，丙酮提取物的抗菌活性最高（12±0.45、20±0.35、20±0.57和15±0.38纳米）。
由于其植物化学成分，库拉索芦荟叶凝胶在缓解与心血管疾病、癌症、神经退行性疾病和糖尿病相关的症状及/或预防这些疾病方面可能具有前景。
