海菜花结合酚的组成、抗氧化活性及其对DNA损伤的保护作用

Composition, Antioxidant Activity and DNA Damage Protective Effect of Bound Phenolics from Ottelia acuminata

采用福林-酚法、亚硝酸钠-氯化铝法分别测定海菜花花、茎、叶中结合酚总酚及黄酮含量,采用高效液相色谱(HPLC)分析结合酚的组成,并研究其抗氧化活性及其对过氧自由基(ROO·)介导的DNA损伤保护作用。结果表明,海菜花结合酚总酚含量为209.72~366.35 mg GAE/g提取物(Extract),黄酮含量为156.69~466.08 mg CAE/g Extract;海菜花结合酚主要含咖啡酸、槲皮素-3-O-葡萄糖苷、木犀草素、绿原酸和阿魏酸5种单体酚;花、茎、叶结合酚的Trolox等量抗氧化活性(TEAC)、1,1-二苯基-2-三硝基苯肼(DPPH)自由基清除能力、铁离子还原抗氧化能力(FRAP)以及对羟基自由基(·OH)清除率IC_(50)值的范围分别为:1.19~1.25μmol TE/g Extract、0.74~0.94 mmol/g Extract、3.61~4.75 mmol Fe^(2+)/g Extract、0.34~1.26 mg/mL,其中叶的抗氧化活性最强;在12.5~500 mg/mL浓度范围内花、茎、叶结合酚对ROO·介导的DNA损伤双螺旋百分比范围分别为22.74%~50.07%、18.25%~53.28%、25.93%~53.60%,其中叶的保护作用最强,其次为茎。研究表明,海菜花结合酚酚类化合物含量丰富,且具有较强的抗氧化活性以及对DNA损伤的保护作用。

Folin-Ciocalteu method and sodium nitrite-aluminum chloride method were used to determine total phenolic content and flavonoid content of bound phenolics from the inflorescences,peduncles and leaves of Ottelia acuminata(O.acuminata),respectively.The composition of bound phenolics was analyzed by high performance liquid chromatography(HPLC).The antioxidant activity and protective effect against ROO·mediated DNA damage were also investigated.The results showed that total phenolic content of O.acuminata was in the range of 209.72~366.35 mg GAE/g Extract while total flavonoid content was in the range of 156.69~466.08 mg CAE/g Extract.Five phenolics,namely,caffeic acid,quercetin-3-O-glucoside,luteolin,chlorogenic acid and ferulic acid were identified in bound phenolics of O.acuminata.Trolox equivalent antioxidant activity(TEAC),1,1-diphenyl-2-trinitrophenylhydrazine(DPPH)radical scavenging ability,iron ion reduction antioxidant ability(FRAP)and hydroxyl radical(·OH)scavenging rate IC_(50) value of different plant parts were in the range of 1.19~1.25μmol TE/g Extract,0.74~0.94 mmol/g Extract,3.61~4.75 mmol Fe^(2+)/g Extract,0.34~1.26 mg/mL,respectively,among which the leaves displayed the strongest antioxidant activity.In the concentration range of 12.5~500 mg/mL,the percentage of double helix DNA in bound phenolics of inflorescences,peduncles and leaves ranged from 22.74%to 50.07%,18.25%to 53.28%and 25.93%to 53.60%,respectively,among which the leaves showed the strongest DNA damage protective effect,followed by the peduncles.The results showed that O.acuminata was rich in bound phenolics which possessed strong antioxidant activity and DNA damage protective effect.