Cho Byoung-Ok, Nchang Che Denis, Yin Hong-Hua, Jang Seon-Il
Research Institute, Ato Q&A Corporation, Jeonju 55069, Republic of Korea.
Department of Health Care & Science, Jeonju University, 303 Cheonjam-ro, Wansan-gu, Jeonju 55069, Republic of Korea.
J Radiat Res. 2017 Sep 1;58(5):647-653. doi: 10.1093/jrr/rrx013.
The aim of this study was to compare the anti-oxidative and anti-inflammatory activities of gamma-irradiated persimmon leaf extract (GPLE) with those of non-irradiated persimmon leaf extract (PLE). Ethanolic extract of persimmon leaf was exposed to gamma irradiation at a dose of 10 kGy. After gamma irradiation, the color of the extract changed from dark brown to light brown. The anti-oxidative and anti-inflammatory activities of GPLE and PLE were assessed from: total polyphenol and total flavonoid contents; 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay; 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) assay, and levels of pro-inflammatory mediators such as nitric oxide (NO), prostaglandin E2 (PGE2), tumor necrosis factor alpha (TNF-α) and interleukin-6 (IL-6). The total polyphenol contents of GPLE and PLE were determined to be 224.44 ± 1.54 and 197.33 ± 5.81 mg gallic acid equivalents (GAE)/g, respectively, and the total flavonoid contents of GPLE and PLE were 206.27 ± 1.15 and 167.60 ± 2.00 mg quercetin equivalents (QUE)/g, respectively. The anti-oxidant activities of GPLE and PLE as measured by DPPH assays were 338.33 ± 30.19 μg/ml (IC50) and 388.68 ± 8.45 μg/ml (IC50), respectively, and those measured by ABTS assays were 510.49 ± 15.12 μg/ml (IC50) and 731.30 ± 10.63 μg/ml (IC50), respectively. IC50 is the inhibitor concentration that reduces the response by 50%. GPLE strongly inhibited the production of NO, PGE2 and IL-6 compared with PLE in lipopolysaccharide-stimulated RAW264.7 macrophages. Furthermore, GPLE significantly inhibited the production of TNF-α and IL-6 cytokines compared with PLE in phorbol 12-myristate 13-acetate (PMA) plus A23187-stimulated HMC-1 human mast cells. These results indicate that gamma irradiation of PLE can enhance its anti-oxidative and anti-inflammatory activities through elevation of the phenolic contents. Therefore, gamma-irradiated PLE has potential for use in the food and cosmetic industries.
本研究旨在比较γ射线辐照柿叶提取物（GPLE）与未辐照柿叶提取物（PLE）的抗氧化和抗炎活性。将柿叶乙醇提取物以10 kGy的剂量进行γ射线辐照。γ射线辐照后，提取物的颜色从深棕色变为浅棕色。通过以下方面评估GPLE和PLE的抗氧化和抗炎活性：总多酚和总黄酮含量；2,2-二苯基-1-苦基肼（DPPH）法；2,2'-联氮-双-（3-乙基苯并噻唑啉-6-磺酸）（ABTS）法，以及促炎介质如一氧化氮（NO）、前列腺素E2（PGE2）、肿瘤坏死因子α（TNF-α）和白细胞介素-6（IL-6）的水平。GPLE和PLE的总多酚含量分别测定为224.44±1.54和197.33±5.81 mg没食子酸当量（GAE）/g，GPLE和PLE的总黄酮含量分别为206.27±1.15和167.60±2.00 mg槲皮素当量（QUE）/g。通过DPPH法测定的GPLE和PLE的抗氧化活性分别为338.33±30.19 μg/ml（IC50）和388.68±8.45 μg/ml（IC50），通过ABTS法测定的分别为510.49±15.12 μg/ml（IC50）和731.30±10.63 μg/ml（IC50）。IC50是使反应降低50%的抑制剂浓度。与PLE相比，在脂多糖刺激的RAW264.7巨噬细胞中，GPLE强烈抑制NO、PGE2和IL-6的产生。此外，与PLE相比，在佛波醇12-肉豆蔻酸酯13-乙酸酯（PMA）加A23187刺激的HMC-1人肥大细胞中，GPLE显著抑制TNF-α和IL-6细胞因子的产生。这些结果表明，PLE的γ射线辐照可通过提高酚类含量增强其抗氧化和抗炎活性。因此，γ射线辐照的PLE在食品和化妆品工业中有潜在用途。
