METHOD FOR QUANTIFYING AMOUNT OF FLAVONOIDS IN LEAVES OF ORDINARY LILAC Russian patent published in 2021 - IPC A61K36/63 A61K31/352 G01N33/15 

FIELD: chemical and pharmaceutical industry.

SUBSTANCE: invention relates to the chemical and pharmaceutical industry and can be used in drug quality control centers and control and analytical laboratories for the quantitative determination of the amount of flavonoids in the leaves of ordinary lilac (Syringa vulgaris L.). A method is described for the quantitative determination of the amount of flavonoids in the leaves of ordinary lilac by obtaining an aqueous-alcohol extract from vegetable raw materials by extraction of 1 g of an exact sample of vegetable raw materials crushed to a particle size of 1 mm with 70% ethyl alcohol, followed by sample preparation and determination of optical density by differential spectrophotometry using a standard sample of rutin, and in its absence, using a theoretical specific absorption index, the extraction of crushed leaves of ordinary lilac is carried out for 45 minutes at a ratio of raw materials: extractant 1:50; quantitative determination of the amount of flavonoids in ordinary lilac leaves is carried out at a wavelength of 412 nm in terms of rutin and the content of the amount of flavonoids in terms of rutin and absolutely dry raw materials is calculated by the formula

where x is the content of the sum of flavonoids in terms of rutin,%; D is the optical density of the test solution; D_o is the optical density of the solution of the State Standard sample of rutin; m is the mass of raw materials, g; m_o is the mass of the State Standard sample of rutin, g; W is the mass loss during drying,%, in the absence of a standard sample of rutin, it is advisable to use the theoretical value of its specific absorption index equal to 240:

where x is the content of the amount of flavonoids in terms of rutin,%; D is the optical density of the test solution; m is the mass of raw materials, g; m_o is the mass of the State Standard sample of rutin, g; 240 is the specific absorption index of the State Standard sample of rutin at 412 nm ; W is the mass loss during drying,%.

EFFECT: described method is effective for quantifying the amount of flavonoids in the leaves of ordinary lilac.

1 cl, 3 dwg, 4 tbl, 2 ex