ДОСЛІДЖЕННЯ АМІНОКИСЛОТНОГО СКЛАДУ СИРОВИНИ RUMEX CONFERTUS WILLD

The genus Rumex comprises 152 species, among which the rhizomes and roots of Rumex confertus are utilized globally, including in Ukraine, where this plant material remains unofficial. Containing phenolic compounds, terpenes, alkaloids, lignans, and organic acids, these underground organs have not been previously analyzed for their qualitative and quantitative amino acid profile, rendering the present investigation highly relevant. The aim of the study. To establish the amino acid composition of the rhizomes and roots of Rumex confertus. Materials and methods. Three series of plant material harvested in autumn 2025 were analyzed to determine the qualitative composition and quantitative content of free and bound amino acids via gas chromatography-mass spectrometry (GC-MS) using an Agilent 6890N/5973 inert GC-MS system (Agilent Technologies, USA). Amino acid identification was performed by comparing the retention times of standards and detecting representative molecular and fragment ions, while quantification was achieved by introducing norvaline (150 μg/sample) as an internal standard. The bound amino acid content was subsequently calculated by subtracting the free amino acid fraction from the total content. This investigation was conducted as part of the National University of Pharmacy research project entitled "Pharmacognostic research of medicinal plant raw materials and development of phytotherapeutic agents based on them" (state registration number 0114U000946). Research results and their discussion. Sixteen free and bound amino acids were identified and quantified in the underground organs of Rumex confertus, with non-essential amino acids predominating across all sample series, ranging from 53% in series 2 to 58% in series 3. The free amino acid fraction remained minimal across all three series, not exceeding 8% of the total amino acid content. In series 1 and 2, the non-essential amino acid glycine predominated in the free fraction, whereas leucine was the major bound essential amino acid; series 3, however, was characterized by the predominance of the non-essential aspartic acid in both free and bound states. The analyzed plant material contained substantial amounts of proline (≥ 6 mg/g), whereas the essential amino acid methionine was accumulated in the lowest quantities. Conclusions. This study provides the first identification and quantification of 16 free and bound amino acids (7 essential and 9 non-essential) in the rhizomes and roots of Rumex confertus. The non-essential amino acid fraction predominates across plant materials from various collection sites, with aspartic acid and proline present in the highest amounts, while leucine represents the most abundant essential amino acid. Containing minimal free amino acids (≤ 8% of the total content), the rhizomes and roots of R. confertus present a specific profile that will inform future investigations aimed at developing herbal medicinal products.