Rodrigues Roberta B, Lichtenthäler Ramona, Zimmermann Benno F, Papagiannopoulos Menelaos, Fabricius Heinz, Marx Friedhelm, Maia José G S, Almeida Ossalin
Institute of Nutrition and Food Sciences, Department of Food Chemistry I, University of Bonn, Endenicher Allee 11-13, D-53115 Bonn, Germany.
J Agric Food Chem. 2006 Jun 14;54(12):4162-7. doi: 10.1021/jf058169p.
The antioxidant capacity of methanol and ethanol seed extracts from Euterpe oleracea Mart. (açaí) against the reactive oxygen species (ROS) peroxyl radicals, peroxynitrite, and hydroxyl radicals was studied with the total oxidant scavenging capacity (TOSC) assay in a modified and automated version. Cold methanol digestion was the most efficient extraction method with respect to the antioxidant capacity. The extracts exhibit good antioxidant capacity against peroxyl radicals, similar to the capacity of the pulp. The antioxidant capacity against peroxynitrite and hydroxyl radicals is even higher. The main antioxidants identified by HPLC-MS and HPLC-CEAD are five different procyanidins (di- through pentamers); furthermore, protocatechuic acid and epicatechin were identified as minor compounds. Determination of TOSC values of HPLC seed extract fractions indicates that the procyanidins contribute substantially to the overall antioxidant capacity. In addition, however, other compounds that have not yet been identified are responsible for a large part of the observed antioxidant capacity.
对来自巴西莓（Euterpe oleracea Mart.）的甲醇和乙醇种子提取物针对活性氧（ROS）过氧自由基、过氧亚硝酸根和羟基自由基的抗氧化能力，采用改良的自动化总抗氧化清除能力（TOSC）测定法进行了研究。就抗氧化能力而言，冷甲醇消化是最有效的提取方法。提取物对过氧自由基表现出良好的抗氧化能力，与果肉的能力相似。对过氧亚硝酸根和羟基自由基的抗氧化能力甚至更高。通过HPLC-MS和HPLC-CEAD鉴定出的主要抗氧化剂是五种不同的原花青素（二聚体至五聚体）；此外，原儿茶酸和表儿茶素被鉴定为次要化合物。对HPLC种子提取物馏分的TOSC值测定表明，原花青素对总体抗氧化能力有很大贡献。然而，此外，其他尚未鉴定的化合物对观察到的大部分抗氧化能力也有作用。
