Basic Science Department, Faculty of Agriculture, Lilongwe University of Agriculture and Natural Resources, Bunda Campus, P.O. Box 219, Lilongwe, Malawi.
Pharmacy Department, Kamuzu University of Health Sciences (KUHeS), P.O. Box 360, Chichiri, Blantyre 3, Malawi.
BMC Complement Med Ther. 2024 Aug 27;24(1):317. doi: 10.1186/s12906-024-04619-7.
This study evaluated and compared the phytochemical and antioxidant properties of the solvent extracts of Azadirachta indica A. Juss and Vernonia amygdalina Del leaves. Methanolic and aqueous extracts showed high (P ≤ 0.05) extract yields (in %), compared to chloroform and ethyl acetate extracts from both V. amygdalina and A. indica leaves. The study exhibited high phytochemical content in methanol and aqueous extracts compared to chloroform and ethyl acetate extracts, confirming the potential for medicinal use. V. amygdalina methanol and aqueous extracts had higher (P ≤ 0.05) total phenolic content (TPC), in mg GAE/gDW, (158.810±0.846 and 217.883±0.265, respectively) than chloroform (37.574±0.118) and ethyl acetate (104.758±0.236) but higher ethyl acetate content in A. indica extracts. Low polar solvents extracted high (P ≤ 0.05) total flavonoids, in mgQE/gDW, (367.051±0.858 and 149.808±0.009) compared to high polar solvents (14.863±0.071 and 54.226±0.014 ) in V. amygdalina while as in A. indica leaf extracts, low polar solvents showed high TFC ( 658.469±3.451 and 275.288±10.490) compared to high polar solvents (26.312±0.063 and 48.858±0.063) respectively. In vitro total antioxidant capacity, in mg/g, was higher in polar solvents than in low-polar solvents, ranging from 34.300±1.784 to 121.015±6.839 for A. indica ethyl acetate and methanolic extracts. A strong correlation between TPC and tannic acid content was observed, except in A. indica methanolic extracts of A. indica. Ferric reducing power was high, except for V. amygdalina chloroform and methanol leaf extracts, which were lower (P≤ 0.05) than that of the standard ascorbic acid. The study revealed that high polar solvents, such as methanol and water, are more efficient in the extraction of antioxidants from A. indica but lower in V. amygdalina extracts. High phytochemical content and antioxidative capacity could be significant in treating various diseases in humans.
本研究评估和比较了印楝（Azadirachta indica A. Juss）和苦艾（Vernonia amygdalina Del）叶的溶剂提取物的植物化学成分和抗氧化特性。与来自苦艾和印楝的氯仿和乙酸乙酯提取物相比，甲醇和水提取物的提取产率（%）较高（P≤0.05）。研究表明，与氯仿和乙酸乙酯提取物相比，甲醇和水提取物中的植物化学成分含量较高，证实了其药用潜力。苦艾甲醇和水提取物的总酚含量（mg GAE/gDW）较高（158.810±0.846 和 217.883±0.265，分别），高于氯仿（37.574±0.118）和乙酸乙酯（104.758±0.236），而印楝提取物中的乙酸乙酯含量较高。低极性溶剂提取的总黄酮（mgQE/gDW）较高（367.051±0.858 和 149.808±0.009），高于高极性溶剂（14.863±0.071 和 54.226±0.014），而在印楝叶提取物中，低极性溶剂的 TFC 较高（658.469±3.451 和 275.288±10.490），高于高极性溶剂（26.312±0.063 和 48.858±0.063）。体外总抗氧化能力（mg/g）在极性溶剂中高于在低极性溶剂中，范围从印楝乙酸乙酯和甲醇提取物的 34.300±1.784 到 121.015±6.839。在印楝叶提取物中，除了鞣酸含量外，观察到总酚含量与鞣酸含量之间存在很强的相关性。铁还原能力较高，除了苦艾叶的氯仿和甲醇提取物较低（P≤0.05）外，均低于标准抗坏血酸。研究表明，高极性溶剂（如甲醇和水）从印楝中提取抗氧化剂的效率更高，但从苦艾中提取的效率较低。高植物化学成分含量和抗氧化能力可能对治疗人类的各种疾病具有重要意义。
