Amensour Mahassine, Sendra Esther, Abrini Jamal, Bouhdid Samira, Pérez-Alvarez José Angel, Fernández-López Juana
Department of Biology, Faculty of Science, Abdelmalek Essaadi University, BP 2121 93002, Tetouan, Morocco.
Nat Prod Commun. 2009 Jun;4(6):819-24.
The total phenolic content and antioxidant activity of methanolic, ethanolic and aqueous extracts of myrtle (Myrtus communis) leaves and berries were measured to find new potential sources of natural antioxidants. Total phenolic content was assessed by the Folin-Ciocalteau assay, while the antioxidant activity was evaluated by three methods: diphenyl-1-picrylhydrazyl (DPPH) radical scavenging capacity assay, the reducing antioxidant power assay and beta-carotene linoleic acid assay. The total phenol content of myrtle extracts ranged between 9.0 and 35.6 mg GAE per g extract. For each solvent, leaf extracts contained significantly higher amount of total phenolic compounds than berry extracts. All of the extracts presented antioxidant capacity assessed by the three methods, but at different levels depending on the concentration, the extraction solvent and the part of the plant used. Generally, leaf extracts showed higher antioxidant activities than berry extracts, while the overall antioxidant strength was in the order methanol > water > ethanol in leaf extracts and methanol > ethanol > water in berry extracts. The phenolic content exhibited a positive correlation with the antioxidant activity: DPPH assay showed the highest correlation (r = 0.949), followed by the reducing power assay (r = 0.914) and the lowest for the beta-carotene linoleic acid assay (r = 0.722).
测定了桃金娘（Myrtus communis）叶和果实的甲醇提取物、乙醇提取物及水提取物中的总酚含量和抗氧化活性，以寻找天然抗氧化剂的新潜在来源。通过福林-酚法测定总酚含量，同时采用三种方法评估抗氧化活性：二苯基-1-苦基肼（DPPH）自由基清除能力测定法、还原抗氧化能力测定法和β-胡萝卜素亚油酸测定法。桃金娘提取物的总酚含量在每克提取物9.0至35.6毫克没食子酸当量之间。对于每种溶剂，叶提取物中总酚类化合物的含量均显著高于果实提取物。所有提取物通过这三种方法评估均具有抗氧化能力，但根据浓度、提取溶剂和所用植物部位的不同而处于不同水平。一般来说，叶提取物的抗氧化活性高于果实提取物，而叶提取物的总体抗氧化强度顺序为甲醇＞水＞乙醇，果实提取物中则为甲醇＞乙醇＞水。酚含量与抗氧化活性呈正相关：DPPH测定法显示的相关性最高（r = 0.949），其次是还原能力测定法（r = 0.914），β-胡萝卜素亚油酸测定法的相关性最低（r = 0.722）。
