Study of Epilobium angustifolium L. amino acids content by HPLC method

The use of plant raw materials is one of the areas of modern pharmaceutical science in the production of herbal drugs. The genus Epilobium counts more than 200 species, many species of which are used in traditional medicine. Among the Epilobium species, Epilobium angustifolium is one of the well-known medicinal plants which have been used worldwide in habitual medicine. There is insufficient information in the literature on the biologically active substances of Epilobium angustifolium L. The presence of three major polyphenol groups: phenolic acids, flavonoids, and ellagitannins were identified in E. angustifolium extracts. Traditionally, the infusion of leaves of this plant could be useful for headaches, cold and gastrointestinal disorder. The Epilobium angustifolium L. as an insufficiently studied plant is a promising object of study, including amino acids composition. To assess the relationship between the production of primary metabolites and their possible therapeutic properties, we analyzed the amino acid profile of the plant Epilobium angustifolium used in traditional medicine. The study of compounds generated by plants as a result of defense mechanisms permits an understanding of the molecular mechanism involved in their medicinal properties. The aim. Thus, the aim of the study was to conduct an HPLC analysis of the amino acids of E. angustifolium to establish the prospects for the use of the raw materials in medical and pharmaceutical practice. The results of the current study will be used in further breeding programs aimed to obtain an industrial form of E. angustifolium suitable for pharmaceutical and food applications. Materials and methods. The determination of amino acids composition of Epilobium angustifolium was conducted using Agilent 1200 (Agilent Technologies, USA). Results. The HPLC method identified sixteen free amino acids and seventeen bound amino acids in the Epilobium angustifolium herb. The studies have shown that Epilobium angustifolium L. herb is mainly composed of free amino acids such as L-phenylalanine (1.65 µg/mg), L-glutamic acid (1.51 µg/mg), L-arginine (1.24 µg/mg), L-alanine (0.98 µg/mg) and L-aspartic acid (0.57 µg/mg), which were presents in the greatest amount. The dominant bound amino acids in the studied raw material were L-glutamic acid, L-aspartic acid, L-leucine, and L-alanine, the content of which was 32.37 µg/mg, 10.59 µg/mg, 8.70 µg/mg, and 6.22 µg/mg respectively. Conclusions. Using the HPLC method determined the amino acids in the herb of Epilobium angustifolium L. The concentrations of L-aspartic acid, L-glutamic acid, L-arginine, L-alanine and L-phenylalanine are predominate among free and bound amino acids in the Epilobium angustifolium L. herb. The result shows that Epilobium angustifolium L. is the source of amino acids, so the use of this plant raw material for new remedies is possible in the future