Aqil Farrukh, Munagala Radha, Vadhanam Manicka V, Kausar Hina, Jeyabalan Jeyaprakash, Schultz David J, Gupta Ramesh C
James Graham Brown Cancer Center, University of Louisville, Louisville, KY 40202, USA.
Food Res Int. 2012 Nov 1;49(1):345-353. doi: 10.1016/j.foodres.2012.07.059. Epub 2012 Aug 7.
Ellagitannins are the most abundant polyphenols in pomegranate () husk and contribute greatly towards its biological properties. A pre-enriched pomegranate husk powder was extracted with water and then further purified by an Amberlite XAD-16 column. Punicalagin (PC) anomers were eluted using a gradient of methanol and water. Fractions eluted with 20% and 25% methanol yielded 1.08 g of light brown powder (purity > 97%) from a total of 40 g of extract. This fraction was identified as PC by HPLC-UV using reference compounds and confirmed by FTICR-MS analysis. PC (10-40 µM) was found to significantly inhibit oxidative DNA products, about 70% inhibition at 40 µM (p=0.0017), resulting from Cu-catalyzed redox cycling of 4-hydroxy-17β-estradiol as analyzed by P-postlabeling. Evidence of high antioxidant activity of PC was also obtained based on ORAC assay (1556±79 µmol of TE/g), as well as by 2,2'-azino-bis (3-ethylbenzthiazoline-6-sulphonic acid) (ABTS)-, 2,2-diphenyl-1-picrylhydrazyl (DPPH)-, hydrogen peroxide (HO) scavenging and ferrous ion-chelating activities (IC=1.1, 17.1, 24 and 45.4 µg/ml, respectively). Further, PC exhibited strong anti-proliferative activity against the human lung, breast and cervical cancer cell lines. Together, these data suggest that PC can be isolated in its purified form by simple column chromatography, inhibits oxidative DNA damage and possesses high anti-proliferative activity.
鞣花单宁是石榴皮中含量最为丰富的多酚类物质，对石榴皮的生物学特性贡献巨大。取预先富集的石榴皮粉末用水进行提取，然后通过Amberlite XAD - 16柱进一步纯化。使用甲醇和水的梯度洗脱石榴皮素（PC）的异头物。用20%和25%甲醇洗脱的馏分从总共40 g提取物中得到1.08 g浅棕色粉末（纯度>97%）。通过使用参考化合物的HPLC - UV将该馏分鉴定为PC，并通过傅里叶变换离子回旋共振质谱（FTICR - MS）分析进行确认。发现PC（10 - 40 μM）能显著抑制氧化性DNA产物，在40 μM时抑制率约为70%（p = 0.0017），这是通过P - 后标记法分析4 - 羟基 - 17β - 雌二醇的铜催化氧化还原循环所导致的。基于氧自由基吸收能力（ORAC）测定（1556±79 μmol TE/g）以及通过2,2'-联氮 - 双 -（3 - 乙基苯并噻唑啉 - 6 - 磺酸）（ABTS）、2,2 - 二苯基 - 1 - 苦基肼（DPPH）、过氧化氢（HO）清除和亚铁离子螯合活性（IC分别为1.1、17.1、24和45.4 μg/ml）也获得了PC具有高抗氧化活性的证据。此外，PC对人肺癌、乳腺癌和宫颈癌细胞系表现出强大的抗增殖活性。总之，这些数据表明PC可以通过简单的柱色谱法以纯化形式分离出来，抑制氧化性DNA损伤并具有高抗增殖活性。
