酶解法对蒙古栎实壳提取物活性成分及抗氧化活性的影响

Effects of extraction methods on extraction components and antioxidant activity of Quercus mongolica shell

【目的】蒙古栎实壳富含多酚、黄酮等活性化合物,具有抗氧化和抑菌等功能。为了深度开发蒙古栎资源,获得抗氧化活性高且高效的制备方法,对不同方法提取的蒙古栎实壳提取物活性成分和抗氧化活性进行比较研究。【方法】采用分光光度法测定溶剂浸提法、高剪切法、超声波法和酶解法这4种方法提取物的总酚、总黄酮、总三萜和可溶性糖物质含量,采用傅里叶变换红外光谱分析4种提取方法对蒙古栎实壳提取物的官能团变化的影响。【结果】4种提取方法对蒙古栎实壳提取物的提取效果和抗氧化活性影响均存在显著性差异,其中酶解法对蒙古栎实壳中酚类化合物的提取效果最好,每100 g蒙古栎实壳的等量总酚含量高达(1.090±0.570) g,FTIR显示酶解法提取的蒙古栎实壳提取物在3 401、1 039 cm^(-1)处的吸收峰强度最大,分别为酚类物质特征基团羟基O-H的伸缩振动和黄酮类物质特征基团C-O-C的伸缩振动。体外抗氧化试验结果表明酶解法提取的蒙古栎实壳提取物抗氧化作用最强,当提取物溶液的质量浓度在0.80 g/L时,·OH清除率高达98.55%,高于VC的清除率(82.03%)。相关性分析表明多酚类物质起主要抗氧化作用。【结论】对溶剂浸提法、高剪切法、超声波法和酶解法提取物活性成分和抗氧化能力进行比较,发现酶解法提取物的活性物质含量最高,抗氧化活性最高。因此,酶解法是从蒙古栎实壳中提取富含抗氧化活性物质的有效方法,且酶解法提取操作简便、成本低,可用于蒙古栎实壳活性物质的制备和天然抗氧化剂的开发。本研究结果为蒙古栎实壳提取物提取技术的选择及抗氧化剂的开发利用提供了理论依据。

[Objective] The solid shell of Quercus mongolica is rich in polyphenols, flavonoids and other active compounds with a variety of functions. In order to further develop Q. mongolica resources and obtain high antioxidant activity and efficient preparation methods, the active components and antioxidant activity of Q. mongolica shell extracts extracted by different methods were compared. [Method] The contents of total phenols, total flavonoids, total triterpenoids and soluble sugar were determined by spectrophotometry.Fourier transform infrared spectroscopy(FTIR) was used to analyze the functional group changes of the extracts of Q. mongolica with 4 extraction methods. [Result] There were significant differences in the effects of the four extraction methods on the extraction efficiency and antioxidant activity of Q. mongolica shell, among which enzymatic hydrolysis method had the best extraction effect on phenolic compounds from Q. mongolica shell, and the total phenolic content per 100 g was as high as(1.090 ± 0.570) g. FTIR showed that the absorption peak intensity was the highest at 3 401 and 1 039 cm^(-1), which were the stretching vibration of hydroxyl O-H and C-O-C of phenolic substances, respectively. In vitro antioxidant test results showed that the antioxidant activity of the extract was the strongest. When the concentration of the extract solution was 0.80 g/L, the scavenging rate of ·OH was 98.55%, which was higher than that of VC(82.03%). Correlation analysis showed that polyphenols played a major role in antioxidant activity.[Conclusion] The active components and antioxidant capacity of extracts extracted by solvent extraction,high shear method, ultrasonic method and enzymatic hydrolysis method were compared. It is found that enzymatic hydrolysis method has the highest content of active substances and antioxidant activity.Therefore, the enzymatic hydrolysis method is an effective method to extract rich antioxidant active substances from Q. mongolica shell, and the enzymatic hydrolysis extraction is simple, low cost, which can be used for the preparation of active substances and natural antioxidant development of Q. mongolica shell.The results of this study provide theoretical basis for the selection of extraction technology of Q. mongolica shell extract and the development and utilization of antioxidants.