Why can't rutin be boiled slowly in cold water at first, but directly in boiling water?

In order to avoid the decomposition of flavonoid glycosides in the extraction process, boiling water was used to destroy the enzyme activity in advance.

High temperature will destroy the activity of enzyme, so that the glycoside in Sophora japonica will not be converted into aglycone by enzyme. The solubility of rutin in Sophora japonica in water changes significantly with temperature. Almost insoluble in cold water, but very soluble in hot water.

Rutin has four phenolic hydroxyl groups in the molecule, and its acidity is weak. Rutin has little solubility in water. When the pH value is too high, rutin is easy to form salt, its solubility increases, and crystallization is less or difficult. If the pH value is too high, there will be too many acidic impurities in rutin.

Extended data:

Rutin has vitamin P-like effect and anti-inflammatory effect, which can alleviate the inflammation caused by mustard oil on animals' eyes or skin and has antiviral effect. When the concentration was 200 μ g mL-1,it had the greatest inhibitory effect on vesicular stomatitis virus. It has a strong antioxidant effect, and the formation of lipid peroxide can be inhibited by adding rutin to lysosomal homogenate. It can strongly absorb 280 ~ 335 nm ultraviolet rays and can be used for sunscreen and whitening cosmetics.

It has the functions of maintaining vascular resistance, reducing its permeability and reducing brittleness. Can be used for preventing and treating diseases such as cerebral hemorrhage, hypertension, retinal hemorrhage, purpura and acute hemorrhagic nephritis.

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