Hosseinimehr Seyed Jalal, Pourmorad Fereshteh, Shahabimajd Naghi, Shahrbandy Kami, Hosseinzadeh Rasa
Department of Medicinal Chemistry, Faculty of Pharmacy, Mazandaran University of Medical Sciences, Sari, Iran.
Pak J Biol Sci. 2007 Feb 15;10(4):637-40. doi: 10.3923/pjbs.2007.637.640.
Extracts of five plants were investigated for their total flavonoids, phenol contents and their radical scavenging activity using DPPH assays: Polygonium hyrcanicum, Centaurea depressa, Sambucus ebulus, Mentha spicata and Phytolacca americana. Quercetin and butylated hydroxy toluene were used as standard reference with well-documented antioxidant activity. Total flavonoid content in these plants ranged from 31.6 to 109.5 mg g(-1) and the amount of free phenolic compounds was between 32 and 287.5 mg g(-1) extract powder. Free phenolic compounds content were in the order: P. hyrcanium > M. spicata > S. ebulus > C. depressa > P. americana. It was also observed that all methanolic extract samples of studied plants showed free radical scavenging activity. The highest antioxidant activity was found in P. hyrcanium with an IC 50 equal to 0.036 mg mL(-1) that is higher than BHT (IC 50 = 0.054). A correlation between radical scavenging capacities of extracts with total phenolic compounds content was observed. This result indicates that P. hyrcanium contains high levels of phenolic compounds that may contribute to higher free radical scavenging activity compared to the other extracts of the plants in this study.
利用DPPH法对5种植物提取物的总黄酮、酚类含量及其自由基清除活性进行了研究，这5种植物分别是：里海蓼、扁苞矢车菊、接骨木、留兰香和美洲商陆。槲皮素和丁基化羟基甲苯用作具有充分文献记载抗氧化活性的标准参照物。这些植物中的总黄酮含量在31.6至109.5毫克/克（-1）之间，游离酚类化合物的含量在32至287.5毫克/克（-1）提取物粉末之间。游离酚类化合物含量顺序为：里海蓼＞留兰香＞接骨木＞扁苞矢车菊＞美洲商陆。还观察到，所研究植物的所有甲醇提取物样品均表现出自由基清除活性。里海蓼的抗氧化活性最高，其半数抑制浓度（IC50）等于0.036毫克/毫升，高于丁基化羟基甲苯（IC50 = 0.054）。观察到提取物的自由基清除能力与总酚类化合物含量之间存在相关性。这一结果表明，与本研究中的其他植物提取物相比，里海蓼含有高水平的酚类化合物，这可能有助于其具有更高的自由基清除活性。
