METHOD FOR QUANTITATIVE DETERMINATION OF SUM OF FLAVONOIDS IN QUEBEC HAWTHORN BERRIES Russian patent published in 2019 - IPC G01N21/00 

FIELD: pharmaceuticals.

SUBSTANCE: invention relates to chemical-pharmaceutical industry, in particular to a method for quantitative determination of the sum of flavonoids in Quebec hawthorn (Crataegus submollis Sarg) berries. Method for quantitative determination of the amount of flavonoids in Quebec hawthorn berries softened with preliminary production of water-alcohol extraction by way of extraction of Quebec hawthorn berries milled with ethyl alcohol in terms of a substance of flavonoid nature by direct spectrophotometry, involves extraction of raw material using as extracting ethyl alcohol with concentration of 70 %, quantitative determination of sum flavonoids in Quebec hawthorn berries is carried out at wavelength 282 nm in terms of catechin; content of sum of flavonoids (X in percentage) in terms of catechine and absolutely dry raw material is calculated by formula:

where: D is the optical density of the test solution; D_o is the optical density of the solution of the standard sample of catechin; m is weight of raw material, g; m_o is mass of standard sample of catechine, g; W is weight loss during drying in percentage. If there is no standard sample of catechine content of sum of flavonoids (X in percentage) in terms of catechine and absolutely dry raw material, it is reasonable to use theoretical value of its specific absorption coefficient equal to 144:

where: D is the optical density of the test solution; m is weight of raw material, g; 144 is specific absorption index (E^1%_1cm) of a standard sample of catechin at 282 nm; W is weight loss during drying in percentage.

EFFECT: method for quantitative determination of sum of flavonoids in Quebec hawthorn berries in terms of catechin.

1 cl, 3 tbl, 3 dwg