五没食子酰葡萄糖锗的合成及其体外抗肿瘤活性

Study on synthesis of 1,2,3,4,6-pentagalloylglucose-germanium( IV)complex and its in vitro antitumor activity

以单宁酸为原料,通过甲醇醋酸溶液降解、乙酸乙酯萃取、葡聚糖凝胶色谱柱纯化,制得1,2,3,4,6-O-五没食子酰葡萄糖(PGG),得率为18%,经HPLC分析纯度为99.90%。采用FT-IR、~1H-NMR、^(13)C-NMR及ESI-MS等分析手段对PGG的结构进行了表征。利用PGG与锗离子在溶液中进行络合反应,反应液经冷冻沉淀、离心、冷冻干燥得到PGG-Ge络合物,采用FT-IR对络合物的结构进行了表征。采用CCK8法研究了PGG-Ge络合物对人结肠癌细胞HCT116、人宫颈癌细胞Hela、人胰腺癌细胞Bx PC3、人小细胞肺癌细胞A549、人胃癌细胞SGC7901及人乳腺癌细胞MCF7增殖的影响。结果表明:PGG-Ge络合物对6种肿瘤细胞的增殖均具有明显的抑制作用,且随着浓度的增加,抑制作用也逐渐增强。当浓度达到160μg/m L时,对6种肿瘤细胞增殖的抑制率均达到了80%左右。而相同浓度下对照品顺铂对受试肿瘤细胞增殖的抑制率只有4.30%～18.54%。PGG-Ge络合物对各肿瘤细胞增殖的IC_(50)值均小于90μg/m L,表现出良好的抗肿瘤活性。

Organic germanium( Ge) compound has wide applications as additives in food and cosmetic products due to its antitumor property. In this study,1,2,3,4,6-Pentagalloylglucose( PGG),which is present at relatively low levels in tannic acid and at even lower levels in plants,was prepared from the degradation of tannic acid with methanolic acetic acid. PGG was then extracted with ethyl acetate,and purified with a Sephadex LH-20 chromatography column.The yield of PGG could reach 18% and the purity was up to 99.90%,which determined by HPLC analysis. The chemical structure of PGG was determined with FT-IR,1 H-NMR,13C-NMR and ESI-MS. PGG-Ge complex was prepared by complexation reaction of PGG with germanium ions followed by cry precipitation,centrifugation,and cryodesiccation.The chemical structure of the complex was characterized by FT-IR. The effects of PGG-Ge on the proliferation of human colon cancer cell HCT116,human cervical cancer Hela,human pancreatic cancer cell BxPC3,human small cell lung cancer cell A549,human gastric cancer cell SGC7901 and human breast cancer cell MCF7 were examined by using CCK8 method. The results showed that the PGG-Ge complex had a significant inhibitory effect on the proliferation of the aforementioned six tumor cells. In addition,the inhibitory effect gradually enhanced with the increase of the PGG-Ge concentration. When the concentration reached 160 μg/mL,the inhibition rate of six tumor cells reached about80%. As a comparison,the inhibition rate for tumor cells of cisplatin was calculated to be only 4.30%-18.54%at the same concentration. The minimum half-inhibiting concentration of proliferation( IC50) of PGG-Ge to each tumor cell was less than 90 μg/mL,indicating good inhibitory effect on proliferation for all aforementioned tumor cells. The result reported in this study is a new polyphenol( PGG)-germanium complex synthesized for the first time.