Lins Patricia Goldschmidt, Marina Piccoli Pugine Silvana, Scatolini Antonio Márcio, de Melo Mariza Pires
Department of Basic Science, Faculty of Animal Science and Food Engineering (FZEA), University of São Paulo, Pirassununga, SP, Brazil.
Heliyon. 2018 Sep 20;4(9):e00805. doi: 10.1016/j.heliyon.2018.e00805. eCollection 2018 Sep.
This study aimed to evaluate antioxidant capacity of olive leaf extract (OLE), L., and its protective effect on peroxyl radical-induced oxidative damage in human erythrocytes.
The OLE was evaluated by the following assays: i) total phenolic and flavonoid content; ii) oleuropein content; iii) Ferric reducing antioxidant power (FRAP); iv) antioxidant activity against ABTS, DPPH and reactive oxygen and nitrogen species: superoxide anion ( ), hypochlorous acid (HOCl) and nitric oxide (NO) and v) protective effect on peroxyl radical-induced oxidative damages in human erythrocytes as hemolysis, thiobarbituric acid reactive substances (TBARS) formation and oxyhemoglobin oxidation.
Total phenolic and flavonoid contents were 131.7 ± 9.4 mg gallic acid equivalents/g dry weight (dw) and 19.4 ± 1.3 mg quercetin equivalents/g dw, respectively. Oleuropein content was 25.5 ± 5.2 mg/g dw. FRAP analysis was 281.8 ± 22.8 mg trolox equivalent/g dw and OLE inhibited ABTS (50% effective concentration (EC) = 16.1 ± 1.2 μg/mL) and DPPH (EC = 13.8 ± 0.8 μg/mL). The extract demonstrated effective ability to scavenge (EC = 52.6 ± 2.1 μg/mL), NO (EC = 48.4 ± 6.8 μg/mL) and HOCl (EC = 714.1 ± 31.4 μg/mL). The extract inhibited peroxyl radical-induced hemolysis (EC = 11.5 ± 1.5 μg/mL), TBARS formation (EC = 38.0 ± 11.7 μg/mL) and hemoglobin oxidation (EC = 186.3 ± 29.7 μg/mL) in erythrocytes.
OLE is an important source of natural antioxidants; it has effective antioxidant activity against different reactive species and protects human erythrocytes against oxidative damage.
本研究旨在评估油橄榄叶提取物（OLE）的抗氧化能力及其对过氧自由基诱导的人体红细胞氧化损伤的保护作用。
通过以下测定评估OLE：i）总酚和黄酮含量；ii）橄榄苦苷含量；iii）铁还原抗氧化能力（FRAP）；iv）针对ABTS、DPPH以及活性氧和氮物种（超氧阴离子、次氯酸（HOCl）和一氧化氮（NO））的抗氧化活性；v）对过氧自由基诱导的人体红细胞氧化损伤（如溶血、硫代巴比妥酸反应性物质（TBARS）形成和氧合血红蛋白氧化）的保护作用。
总酚和黄酮含量分别为131.7±9.4毫克没食子酸当量/克干重（dw）和19.4±1.3毫克槲皮素当量/克dw。橄榄苦苷含量为25.5±5.2毫克/克dw。FRAP分析结果为281.8±22.8毫克Trolox当量/克dw，且OLE抑制ABTS（半数有效浓度（EC）=16.1±1.2微克/毫升）和DPPH（EC=13.8±0.8微克/毫升）。该提取物表现出有效清除超氧阴离子（EC=52.6±2.1微克/毫升）、NO（EC=48.4±6.8微克/毫升）和HOCl（EC=714.1±31.4微克/毫升）的能力。该提取物抑制过氧自由基诱导的红细胞溶血（EC=11.5±1.5微克/毫升）、TBARS形成（EC=38.0±11.7微克/毫升）和血红蛋白氧化（EC=186.3±29.7微克/毫升）。
OLE是天然抗氧化剂的重要来源；它对不同的活性物种具有有效的抗氧化活性，并保护人体红细胞免受氧化损伤。
