Phaseolus vulgaris Linn. is a medicinal and edible plant resource. The edible value of white kidney beans lies in their rich amino acid content. The medicinal value lies in the alpha-amylase inhibitor in White Kidney Bean Extract. In addition, the polysaccharides, polyphenols, and mineral elements in white kidney beans provide them with a wide range of biological activities, such as antioxidant, anti-obesity, etc. The above factors make it a medicinal and edible homologous plant with great development potential, and it has attracted great attention from food and drug companies and related research institutions.
Functional Components of White Kidney Bean
1. Glycoprotein: α-AI (α-amylase inhibitor)
α-AI acts mainly on mammalian and insect α-amylases. The α-AI three-dimensional structure is completely devoid of carbohydrate surface-binding loops. It has no carbohydrate binding capacity and is a non-competitive inhibitor. Therefore, its inhibitory effect on α-amylase with higher activity is not obvious. And its inhibitory effect is not affected by starch concentration, and can be widely used to inhibit the starch hydrolysis of daily diet by α-amylase. It can effectively reduce postprandial blood sugar levels, providing a new choice for diabetic diets.
2. Polysaccharides
White kidney bean polysaccharide is a mixture rich in various types of pectin, which has the functions of lowering blood sugar, lowering blood lipid and good in vitro antioxidant
chemical effect. The molecular structure characteristics of polysaccharide determine its functional activity, so it is of certain value to study the structure and composition of white kidney bean polysaccharide for its application.
3. Dietary fiber
The hull quality of white kidney beans accounts for 7.5%~8.0% of the granule quality, which is higher than that of soybeans. It is an excellent raw material for dietary fiber.
The mass scores of soluble dietary fiber and unable to soluble dietary fibers were 3.5%and 19.8%, respectively.
Bean flour contains 1.14%of water -soluble fibers, and bean slag contains 43.49%insoluble dietary fiber. The soluble dietary fiber of white kidney beans is mainly composed of arabinose, galactose, glucose, mannose and galacturonic acid, of which arabinose and galactose are the two main neutral sugars, and the content of arabinose is higher than that of galactose.
4. resistance starch
Resistant starch is similar in properties to soluble fiber, has a certain effect of regulating body fat, and can prevent diabetes and obesity. The content of resistant starch in white kidney beans was detected to be 9.13%-16.35%. Due to the different treatment effects of chemical extraction and enzymatic hydrolysis on white kidney beans, there will be differences in resistant starch content. In addition, the variety and planting region will also affect the level of resistant starch.
5. Polyphenol
The antioxidant activity of white kidney beans is reflected in the richness of polyphenols. The mass fraction of total phenols was 0.67~2.22 mg RTE/g DW. The mass fraction of total flavonoids was 0.78-1.33 mg RTE/g DW. The extraction rate of sprouts polyphenols was also 2.76%, and the purity was 32.29%. Studies have shown that white kidney beans contain 14 kinds of phenolic acid and derivatives such as sulutic acid, cordinoplasma, and non -meal acid. The gallic acid content is nearly 10 times that of black beans. In addition, white kidney beans have other active components, such as peroxidase, oligosaccharides, saponins, beta-carotene tocopherols, saponins, and rich minerals such as K, Ca, and Mg. This lays the material basis for its wide range of biological activities.