Optimization of methods and modes of extraction of biologically active substances from plant raw materials

The paper considers traditional and modern methods of obtaining phenolic compounds from plant raw materials and cellular (in vitro) plant cultures and provides a comparative analysis. Hypericum perforatum (kombucha), Melilotus officinalis (verbena) and Portulaca oleracea (purslane) were selected as the objects of research.The relevance of the study is due to the increased demand for natural phenolic compounds as sources of antioxidants and functional ingredients, as well as the need to develop effective, economically and environmentally friendly technologies for their production.The purpose of the study – determination of the optimal method for obtaining phenolic compounds in terms of yield, stability and technological effectiveness of bioactive compounds.70% ethanol extractant was used in the work, and three methods were compared – maceration, Soxlet extraction and Ultrasonic extraction (UAE).According to the results of the study, the largest amount of phenolic compounds was obtained by the Soxlet method: in natural plant raw materials, 61.2±2.4 mg GAE/g for Hypericum perforatum, 56.3±1.9 mg GAE/g for melilotus officinalis and 45.7±1.5 mg GAE/g for Portulaca oleracea were recorded. The ultrasonic extraction method showed GAE/g values of 58.4±2.1; 44.1±1.5 and 32.8±1.1 mg, respectively, which is higher than that of the maceration method, but lower than that of Soxlet. The lowest values were observed during maceration (in the range of 24.2-42.6 mg GAE/g).It was found that in extracts obtained from In vitro cultures, the content of phenolic compounds is on average 10-20% lower than in natural plant raw materials.As a result of optimization of extraction parameters, it was found that 70% ethanol and a temperature range of 50-70 °C are optimal for the effective production of phenolic compounds, while the maximum values were recorded at 70 °C. Comparative analysis has shown that the Soxlet method provides maximum yield, but requires high temperatures and energy consumption. Although the ultrasonic extraction method has a slightly lower yield, it is more effective and promising in terms of a short extraction time (30 minutes), lower solvent consumption and preservation of biologically active compounds. Thus, the results of the study showed that the choice of a method for producing phenolic compounds should depend on a specific goal: for maximum yield, the Soxlet method is used, and for technological efficiency, energy efficiency and product quality preservation, the ultrasonic extraction method is proposed. The results obtained can be used in the development of technologies for the production of plant extracts in the food industry and the production of functional products.