DEAE-52纤维素柱层析纯化处理对西梅可溶性膳食纤维的影响

Effect of DEAE-52 cellulose column chromatography on soluble dietary fiber of prune

以西梅为研究对象,采用DEAE-52纤维素柱层析纯化粗提西梅可溶性膳食纤维(prune soluble dietary fiber,PSDF)。通过仪器分析法对纯化前后的PSDF进行初步结构表征,并测定其纯度、基本成分、抗氧化活性和理化特性。结果表明,PSDF纯化处理后纯度由(77.54±0.52)%提高至(93.16±0.44)%,纯化效果良好。紫外光谱显示,纯化处理后的PSDF蛋白质被去除,红外光谱显示2种PSDF均为含有α-糖苷键且具有吡喃环的多糖。扫描电镜结果显示,纯化处理可使PSDF的比表面积大幅度增大,其表面结构由光滑平坦状变为蜂巢型的多孔网状结构,有助于理化性质的提高。GC-MS结果显示,PSDF是由葡萄糖、果糖、甘露糖和阿拉伯糖组成的杂多糖。抗氧化活性测定结果表明,纯化处理导致PSDF抗氧化活性下降,样品质量浓度为2.0 mg/mL时,粗提PSDF和纯化PSDF对ABTS阳离子自由基清除率的IC 50值分别为0.933、1.278 mg/mL,对DPPH自由基清除率的IC 50值分别为1.071、2.178 mg/mL,对超氧阴离子自由基清除率的IC 50值分别为1.826、2.243 mg/mL。理化特性结果显示,纯化处理后PSDF持水力、持油力、膨胀力和胆固醇吸附能力均显著提高(P<0.05),分别达(8.51±0.06)g/g、(5.07±0.1)g/g、(13.94±0.14)mL/g、(13.41±0.21)mg/g,葡萄糖吸附能力下降至(4.82±0.08)mg/g。综上结果表明,该纯化方法是一种较好的纯化膳食纤维的方法,可为膳食纤维的纯化加工提供理论依据,对提高西梅膳食纤维利用率和开发相关功能性产品提供参考。

In this study,the crude extracted prune soluble dietary fiber(prune soluble dietary fiber,PSDF)was purified by DEAE-52 cellulose column chromatography using prune as the research object.The preliminary structural characterization of PSDF before and after purification was carried out by instrumental analysis,and its purity,basic components,antioxidant activity,and physicochemical properties were determined.Results showed that the purity of PSDF increased from(77.54±0.52)%to(93.16±0.44)%after the purification treatment.The ultraviolet spectrum showed that the protein of PSDF was removed after purification treatment,and the infrared spectrum showed that both PSDF were polysaccharides containingα-glycosidic bond with the pyran ring,and the results of scanning electron microscopy showed that the purification treatment could make the specific surface area of PSDF increase greatly,and the surface structure of the PSDF was changed from smooth and flat to honeycomb porous mesh structure,which could help to improve the physicochemical properties,and the results of GC-MS showed that PSDF was composed of glucose,fructose,mannose and arabinose.The results of antioxidant activity assay showed that the purification treatment led to a decrease in the antioxidant activity of PSDF,and the IC 50 values of the scavenging rate of ABTS cationic radicals were 0.933 and 1.278 mg/mL for crude and purified PSDF,respectively,and the IC 50 values of the scavenging rate of DPPH free radicals were 1.071 and 2.178 mg/mL,respectively,and the IC 50 values of the scavenging rate of·O 2-radicals were 1.826 and 2.243 mg/mL,respectively.The results of physicochemical characterization showed that the water-holding capacity,oil-holding capacity,swelling capacity,and cholesterol adsorption capacity of PSDF were significantly increased after purification treatment(P<0.05),amounting to(8.51±0.06)g/g,(5.07±0.1)g/g,(13.94±0.14)mL/g,(13.41±0.21)mg/g,and the glucose adsorption capacity decreased to(4.82±0.08)mg/g.In summary,the conclusions indicate that the purification method is a better way to purify dietary fiber,which can provide a theoretical basis for the purification and processing of the dietary fiber,and provide a reference to improve the utilization rate of dietary fiber in prunes and develop related functional products.