Приведена методика дифференциального количественного определения дубильных веществ (ДВ) в лекарственном растительном сырье и лекарственных растительных препаратах. Основной особенностью описанной методики является возможность изменения условий определения (стандартное вещество, аналитическая длина волны, навеска испытуемого образца) с учетом групповой принадлежности основной массы экстрагируемых ДВ.

The quality control of the «Valerian rhizome and roots» herbal substance is carried out using high performance liquid chromatography (HPLC) according to the State Pharmacopoeia of the Russian Federation, XIV edition. The quantitative analysis of the active ingredients in valerian tincture is performed using a non-specific and non-selective spectrophotometric method. Therefore, it is important to introduce in Russia a more modern test procedure for quantitative determination of active ingredients in valerian tincture.The aim of the study was to develop a selective and sensitive HPLC procedure for quantitative determination of the total content of sesquiterpenic acids, expressed as valerenic acid, for the purpose of valerian tincture standardisation.Materials and methods: valerian tincture samples produced by seven Russian manufacturers were used as test samples, and valerenic acid was used as the reference standard. The quantitative analysis of the active ingredients was performed by two methods: spectrophotometry at 512 nm following the reaction of valerenic acid ethylester with hydroxyalamine and ferric chloride, and by HPLC using a Nucleosil C18 column, 125×4.6 mm, 5 µm particle size, in gradient elution mode, with detection at 220 nm.Results: the spectrophotometric technique was shown to be insufficiently specific. The authors of the study validated the chromatographic test procedure, established system suitability criteria, and compared the results obtained by the two test procedures. They also determined a tentative standard of the total content of sesquiterpenic acids, expressed as valerenic acid, obtained by HPLC.Conclusions: the HPLC assay developed for quantitative determination of active ingredients in valerian tincture is more specific as compared to the spectrophotometric technique, as the sum of the peaks of valerenic and acetoxyvalerenic acids and the results for the reference standard are taken into account during calculations. The new test procedure is in line with the cross-cutting standardisation principle and can be recommended for inclusion into the draft monograph «Valerian tincture».

The process of harmonisation of Russian and foreign approaches and requirements in the field of medicines quality assurance calls for revision of quality control procedures included in various regulations and guidelines. The monograph FS.2.5.0062.18 “Hawthorn flowers” of the State Pharmacopoeia of the Russian Federation XIV edition includes a test procedure for determination of flavonoids by a chromatospectrophotometric method. This procedure does not take into account current scientific capabilities and has a number of shortcomings, therefore it was necessary to revise the existing test procedure and develop a new approach to the standardisation of the hawthorn flower herbal substance.The objective of the study was to develop an assay method for standardisation and evaluation of hawthorn flower using high performance liquid chromatography (HPLC).Materials and methods: the study was performed using samples of hawthorn flowers by Russian manufacturers. Quercetin (USP RS) and Hyperoside (HWI, primary standard) were used as the reference standards. The HPLC analysis was performed using an Infinity II 1260 DAD LC system (Agilent), and the UV spectra were recorded on a Cary 100 Varian spectrophotometer. A TLC Visualizer (CAMAG) was used to obtain digital images of thin layer chromatography plates.Results: the authors developed an HPLC test procedure for quantitative determination of total flavonoids, expressed as hyperoside, in hawthorn flowers. The developed procedure gives reliable and reproducible results and is characterised by high sensitivity and selectivity. The results of quantitative determination of the total flavonoid content in hawthorn flowers were used to propose the standard for the total content of flavonoids, expressed as hyperoside, of “not less than 0.5%”.Conclusions: the developed assay method for determination of active pharmaceutical ingredients in hawthorn flower products by HPLC can be recommended for inclusion into the Assay part of the “Hawthorn Flowers” monograph of the State Pharmacopoeia of the Russian Federation.

Specialists in pharmacognosy are facing an important task of improving quality control methods for combination herbal medicinal products in order to enable reliable assessment of the content of active substances that are responsible for the drug’s pharmacological effect.The aim of the study was to investigate the possibility of using the European Pharmacopoeia method to determine the total content of anthracene derivatives in the antihaemorrhoidal medicinal herb mixture Proctophytol® and to propose limit values for the total content of anthracene derivatives.Materials and methods: individual mixture components containing anthracene derivatives, such as senna leaves and frangula bark, as well as model mixtures containing these individual components in a 1:1 ratio, and a model mixture imitating Proctophytol® were used in the study. The determination of the anthracene derivatives content was carried out using spectrophotometry.Results: it was demonstrated that the European Pharmacopoeia method could be used to assess the quality of Proctophytol® in terms of anthracene derivatives total content. The spectrophotometric method described in the European Pharmacopoeia has advantages over the methods described in manufacturer specifications for Russian products, because it allows for thorough extraction of the active substances and is standardized for anthracene derivatives.Conclusions: the European Pharmacopoeia method was adjusted to determine anthracene derivatives in the medicinal herb mixture Proctophytol®. It was proposed to use 70% ethanol instead of 70% methanol as extraction solvent. The authors identified optimum sample weights and test solution dilutions, and calculated and verified the limit for anthracene derivatives content—“Not less than 1.9%”. The adjusted method can be recommended for inclusion in the monographs of the State Pharmacopoeia of the Russian Federation for medicinal herb mixtures similar to Proctophytol®.