苦荞麸皮多酚抑制人结肠癌细胞Caco-2增殖活性研究

研究了产自重庆酉阳的苦荞(Fagopyrum tartaricum L.Gaerth,FG1)麸皮和四川西昌的苦荞(Fagopyyrum tartaricum L.Gaerth,FG2)麸皮中酚类化合物的含量、抗氧化和抗增殖活性。结果表明:FG1和FG2 2种苦荞麸皮总酚含量分别为(26.40±0.41)和(27.00±0.72)mg GAE/g DW,且游离态是其酚类化合物的主要存在形式(约占其总酚含量的93%);2种苦荞麸皮酚提取物均表现出一定的抗氧化性,并且FG2的抗氧化能力强于FG1(P0.05),FG1和FG2的DPPH自由基清除能力总IC50值分别为(39.56±2.76)和(24.69±0.33)μg·mL~(-1);还原力总EC_(50)值分别为(97.92±1.4)和(73.18±4.32)μg·mL~(-1);在抗增殖试验中,与对照组相比,FG1和FG2游离酚提取物均能明显抑制人结肠癌细胞Caco-2增殖(P0.05)。然而,在不产生细胞毒性的浓度范围内,其结合酚提取物却表现出极弱的抗增殖作用。

Antiproliferative Activity toward Human Colon Cancer Cell (Caco-2) of Phenolic compounds in Fagopyrum tartaricum (L.) Gaertn Brans

The extracts from two Fagopyrum tartaricum (L.) Gaertn brans which were harvested from Youyang County, Chongqing (FG1) and Xichang City, Sichuan (FG2) were screened for free and bound phenolic content or total phenolic content (TPC) , as well as antioxidant and antiproliferative activity.The results showed that the TPC of FG1 and FG2 were 26.40± 0.41 and 27.00± 0.72 mg GAE/g DW, respectively. Free phenolics, which account for about 93% of the TPC, were predominant in the two buckwheat brans. Phenolic compounds of FG1 and FG2 all exhibited antioxidant activity with the total IC50 39.56±2.76 and 24.69±0.33 ug?mL-1(DPPH free radical scavenging activity), respectively; EC50 97.92±1.4 and 73.18±4.32 ug?mL-1(reducing power), respectively. In the antiproliferative activity assay, the free phenolic extracts of FG1 and FG2 showed significantly antiproliferative activity toward human colon cancer cells (Caco-2) in vitro, when compared to the control (P< 0.05). However, the bound phenolics of FG1 and FG2 showed extrmely weak inhibitory toward Caco-2 cells within non-cytotoxic concentrations.