Text this: Use of Capillary Electrophoresis Method in Determination of Quantitative Content of Mangiferin in Grass of Species of Genus Hedysarum (Hedysarum Caucasicum M.Bieb., Hedysarum Grandiflorum Pall., Hedysarum Daghestanicum Rupr. ex Boiss) of flora of the North Caucasus