Methods have been developed for the quantitative determination of biologically active compounds - flavonoids and vitamin K1 in the liquid extract "Extradent" obtained from the aerial part of the knotweed (Polygonum hidropiper L.), shepherd's purse (Bursa pastoris), calendula flowers (Calendulae officinalis) and nettle leaves (Urtica dioica). L.), by high performance liquid chromatography (HPLC). As a result, components corresponding to the retention time of standard samples of robinin, rutin, and quercetin were found on the chromatogram of the extract. It was revealed that the content of robinin was 0.37%, rutin 0.014%, quercetin 0.00045%, and vitamin K1 0.005%. The same method of mass spectrometry with inductively coupled plasma (ICP-MS) was used to determine the quantitative content of macro- and microelements of the liquid extract "Extradent". The highest content of macroelements is in the proportion of potassium (0.65%), phosphorus (0.2%), and among the microelements of iron is 15.716 mg/l, selenium – 0.046 mg/l. The content of heavy metal salts in the liquid extract is within the normal range and totals 1.155 mg/l. Of these, the main content is zinc and copper.