Method for extracting alpha-amylase inhibitor from white kidney beans by use of microwave-compound enzyme coupling method

The invention discloses a method for extracting an alpha-amylase inhibitor from white kidney beans by use of a microwave-compound enzyme coupling method. According to the method, the white kidney beans are used as raw materials; the alpha-amylase inhibitor in the white kidney beans can be dissolved and separated out from the white kidney beans in an acceleration manner through microwave-compound enzyme coupling treatment after the white kidney beans are smashed; meanwhile, impurities such as fat, proteins and saccharides can be removed from the white kidney beans by only dozens of minutes through enzyme hydrolysis by one step under microwave-compound enzyme coupling catalytic hydrolysis, so that the purity of the alpha-amylase inhibitor in a coarse extract is much higher than that of the alpha-amylase inhibitor extracted by the common coarse extraction method; a pure high-activity alpha-amylase inhibitor can be obtained through ultrafiltration and ion column chromatographic refining. According to the method disclosed by the invention, the extraction condition is mild; water is used as a solvent, so that the pure nature of the product can be guaranteed; furthermore, due to the microwave-compound enzyme coupling method, the time for extracting the pure product is greatly shortened, and the inhibition activity of the product is over 90 percent; basic raw materials can be supplied to promotion of the development of a sugar reduction and fat reduction market in China.