玉米芯功能性低聚糖分级纯化及抗氧化活性研究

探究玉米芯功能性低聚糖分级纯化前后不同组分的组成、理化性质和抗氧化活性。以玉米芯为原料，采用活性炭柱层析法对玉米芯功能性低聚糖进行分级纯化，对纯化前后组分的聚合度、相对分子质量、阿魏酸基团以及红外光谱特性进行分析，并对酶解低聚糖粗提物（Enzymatic hyrolysates, EH）及其纯化组分的自由基清除能力和抑制脂质过氧化能力进行比较分析。结果表明：活性炭水洗脱低聚糖组分（Water elution oligosaccharides,WO）、醇洗脱低聚糖组分（Ethanol elution oligosaccharides, EO）均主要由木糖和阿拉伯糖组成，其中WO含有结合态阿魏酸，为阿魏酰阿拉伯低聚木糖；EO不含结合态阿魏酸，为阿拉伯低聚木糖。EH及其纯化组份WO、EO均具有一定的清除自由基（DPPH?、?OH、ABTS+?）能力和抑制脂质过氧化能力，且随浓度的增加而增加，WO抗氧化活性最强，EH次之，EO抗氧化活性较弱。

Fractional Purification and Antioxidant Activity of Functional Oligosaccharides from Corn Cob

The composition, physicochemical properties and antioxidant activity of different components of corn cob functional oligosaccharides before and after fractionation and purification were investigated. The functional oligosaccharides from corn cob were fractionated and purified by activated carbon column chromatography. The degree of polymerization, relative molecular mass, ferulic acid group and infrared spectral characteristics of the fractions before and after purification were analyzed. The free radical scavenging ability and lipid peroxidation inhibition ability of enzymatic hydrolysate oligosaccharides (EH) and its purified fractions were compared and analyzed. The results showed that the water elution oligosaccharides (WO) and ethanol elution oligosaccharides (EO) were mainly composed of xylose and arabinose, and WO contained bound ferulic acid, which was feruloyl arabinose oligosaccharides. EO does not contain bound ferulic acid and is an arabinoxylan oligosaccharide. EH and its purified components WO and EO had certain ability to scavenge free radicals (DPPH?,?OH, ABTS+) and inhibit lipid peroxidation, and increased with the increase of concentration. WO had the strongest antioxidant activity, followed by EH, and EO had weak antioxidant activity.