阳春砂根茎多糖分离纯化、结构表征及抗氧化活性

Purification,structural characterization and antioxidant activity of polysaccharide from the rhizome of Amomum villosum Lour

该文以阳春砂根茎为原料,对阳春砂根茎多糖(Amomum villosrm rhizome polysaccharide,AVRP)进行分离纯化,并进一步研究结构特征和抗氧化活性,为后续开发利用提供依据。利用DEAE-52和Sephadex G-100柱色谱分离纯化得到AVRP-1。通过化学成分、高效凝胶渗透色谱、HPLC和傅里叶红外光谱分析对AVRP-1结构进行表征,以DPPH自由基和羟自由基清除率评价AVRP-1的抗氧化活性。结果显示,AVRP-1总糖含量为90.34%,蛋白质含量为0.64%,糖醛酸含量为43.59%;相对分子质量为3372.01 kDa,是一种大分子质量酸性多糖;由甘露糖、鼠李糖、葡萄糖醛酸、半乳糖醛酸、葡萄糖、半乳糖和阿拉伯糖7种单糖组成,摩尔比为4.14∶4.98∶5.10∶23.77∶17.30∶28.51∶16.19;α和β构型的糖苷键是同时存在的;AVRP-1具有抗氧化活性,对DPPH自由基和羟自由基的半数有效浓度(half-maximal effective concentration,EC_(50))分别为4.50和2.47 mg/mL。研究结果表明,AVRP-1可作为天然抗氧化剂用于医药和功能性食品行业,该研究结果为充分利用阳春砂提供了理论基础。

The rhizome of Amomum villosum was used as raw material to obtain the purified polysaccharide(AVRP-1),and the structural characteristics and antioxidant activities of AVRP-1 were further studied.DEAE-52 and Sephadex G-100 column chromatography were used to obtain AVRP-1.And the structure of AVRP-1 was characterized by chemical composition,high-performance gel permeation chromatography(HPGPC),HPLC and Fourier transform infrared(FT-IR)spectroscopy.The antioxidant activity of AVRP-1 was assessed based on the DPPH and hydroxyl radical scavenging rates in vitro.The results showed that the content of total sugar,protein and uronic acid of AVRP-1 was 90.34%,0.64%and 43.59%,respectively.The relative molecular weight of AVRP-1 was 3372.01 kDa.Moreover,AVRP-1 was composed of mannose,rhamnose,glucuronic acid,galacturonic acid,glucose,galactose and arabinose in the molar ratio of 4.14∶4.98∶5.10∶23.77∶17.30∶28.51∶16.19.The glycosidic bonds existed in both and configurations.The assay of antioxidant activity of AVRP-1 revealed that its half-maximal effective concentration(EC_(50))for DPPH and hydroxyl radical scavenging activity was 4.50 and 2.47 mg/mL,respectively.These results showed that AVRP-1 could be used as a natural antioxidant substance in the pharmaceutical and functional food industry,and provide a theoretical basis for making full use of A.villosum.