Division of Food Science, Institute of Animal Reproduction and Food Research of the Polish Academy of Sciences, Tuwima Street 10, 10-474 Olsztyn, Poland.
Instituto de Fermentationes Industriales (CSIC), Juan de la Cierva 3, 2800 Madrid, Spain.
Int J Mol Sci. 2009 Dec 23;10(12):5513-5527. doi: 10.3390/ijms10125513.
Phenolic compounds were extracted from red lentil seeds using 80% (v/v) aqueous acetone. The crude extract was applied to a Sephadex LH-20 column. Fraction 1, consisting of sugars and low-molecular-weight phenolics, was eluted from the column by ethanol. Fraction 2, consisting of tannins, was obtained using acetone-water (1:1; v/v) as the mobile phase. Phenolic compounds present in the crude extract and its fractions demonstrated antioxidant and antiradical activities as revealed from studies using a beta-carotene-linoleate model system, the total antioxidant activity (TAA) method, the DPPH radical-scavenging activity assay, and a reducing power evaluation. Results of these assays showed the highest values when tannins (fraction 2) were tested. For instance, the TAA of the tannin fraction was 5.85 micromol Trolox eq./mg, whereas the crude extract and fraction 1 showed 0.68 and 0.33 micromol Trolox eq./mg, respectively. The content of total phenolics in fraction 2 was the highest (290 mg/g); the tannin content, determined using the vanillin method and expressed as absorbance units at 500 nm per 1 g, was 129. There were 24 compounds identified in the crude extract using an HPLC-ESI-MS method: quercetin diglycoside, catechin, digallate procyanidin, and p-hydroxybenzoic were the dominant phenolics in the extract.
采用 80%（v/v）水丙酮从红扁豆种子中提取酚类化合物。粗提物应用于 Sephadex LH-20 柱。由糖和低分子量酚组成的馏分 1 用乙醇从柱上洗脱。由单宁组成的馏分 2 用丙酮-水（1:1；v/v）作为流动相获得。粗提物及其馏分中存在的酚类化合物表现出抗氧化和抗自由基活性，这是从使用β-胡萝卜素-亚油酸模型系统、总抗氧化活性（TAA）方法、DPPH 自由基清除活性测定和还原能力评估研究中揭示的。当测试单宁（馏分 2）时，这些测定的结果显示出最高的值。例如，单宁馏分的 TAA 为 5.85 微摩尔 Trolox eq./mg，而粗提物和馏分 1 分别为 0.68 和 0.33 微摩尔 Trolox eq./mg。馏分 2 中的总酚含量最高（290mg/g）；使用香草醛法测定并以每 1g 在 500nm 处的吸光度单位表示的单宁含量为 129。使用 HPLC-ESI-MS 方法在粗提物中鉴定出 24 种化合物：槲皮素二糖苷、儿茶素、二没食子酰基原花青素和对羟基苯甲酸是提取物中的主要酚类化合物。
