燕麦β-葡聚糖-槲皮素复合物的制备及其对秀丽隐杆线虫寿命的影响

Preparation of Complex of Oats β-glucan and Quercetin and Its Effect on Lifespan of Caenorhabditis elegans

摘要:

为探究糖酚复合物的结构及功能特性,采用自由基催化、氢键吸附技术分别制备燕麦β-葡聚糖与槲皮素共价(COGQ)及非共价复合物(NOGQ),利用高效排阻色谱、红外光谱和核磁波谱等方法分析其结构特性,以秀丽隐杆线虫(简称线虫)为模型,研究复合物的抗衰老活性。高效排阻色谱显示,NOGQ和COGQ的相对分子质量分别为354、349kDa,两者相差不大；红外光谱显示,复合物在1660、1562、1243cm-1处有新的红外吸收峰,呈非晶态相,无定型状态；核磁波谱表明,复合物在化学位移为6.5~8.5处可产生3个属于苯基质子的新质子信号,有3个单糖残基；抗衰老活性研究表明,与空白组相比,COGQ与NOGQ均能显著提高秀丽隐杆线虫的平均寿命(P＜0.05),且两组中线虫体内的超氧化物岐化酶和过氧化氢酶活性均显著提高(P＜0.01),揭示两种复合物可能通过提高机体的抗氧化能力,进而发挥其延长寿命的功效。研究结果旨在为糖酚复合物的制备及新型食品抗氧化剂的开发提供参考。

Abstract:

The covalent and non-covalent complex of β-glucan of oats and quercetin were prepared using radical catalysis and hydrogen bond adsorption methods, named COGQ and NOGQ, respectively. Their molecular structures were characterized using HPSEC (high performance size exclusion chromatography), FT-IR spectrometry and NMR (nuclear magnetic resonance) spectroscopy. The anti-aging activities of the complex were evaluated by Caenorhabditis elegans(C. elegans) model. Results from HPSEC showed that the relative molecular weights of NOGQ and COGQ were 354kDa and 349kDa, respectively, which were not much different. Compared with β-glucan of oats, both complexes demonstrated several new infrared absorption peaks at 1660cm-1, 1243cm-1 and 1562cm-1 and polysaccharide and polyphenols conjugates are amorphous. According to the NMR data, three monosaccharide residues were observed in the anomeric region of ¹H spectrum and three new proton signals at 6.5-8.5 were attributed to phenyl groups in the complex. Compared with the control group, COGQ and NOGQ significantly increased the average lifespan of C. elegans (P<0.05), and the activities of SOD and CAT in both groups were significantly increased (P<0.01), suggesting that COGQ and NOGQ composites may prolong the lifespan of C. elegans by improving the antioxidant capacity of the body. The results could provide a reference for the preparation of polysaccharides and polyphenol composites and the development and utilization of them as novel food antioxidants.