###### Abstract
);[EMAIL_ADDRESS] (A.M.-S.);[PERSON]RESS] (A.M.-S.);[EMAIL_ADDRESS] (A.M.-S.);[EMAIL_ADDRESS] (A.M.-S.);[PERSON]RESS] (A.M.-S.);[EMAIL_ADDRESS] (A.M.-S.);[PERSON]RESS] (A.M.-S.);[EMAIL_ADDRESS] (A.M.-S.);[EMAIL_ADDRESS] (A.M.-S.);[EMAIL_ADDRESS] (A.M.-S.);[EMAIL_ADDRESS] (A.M.-S.);[EMAIL_ADDRESS] (A.M.-S.);[EMAIL_ADDRESS] (A.M.-S.);[EMAIL_ADDRESS] (A.M.-S.);[EMAIL_ADDRESS] (A.M.-S.);[EMAIL_ADDRESS] (A.M.-S.);[EMAIL_ADDRESS] (A.M.-S.);[EMAIL_ADDRESS] (A.M.-S.);[PERSON]RESS] (A.M.-S.);[EMAIL_ADDRESS] (A.M.-S.);[EMAIL_ADDRESS] (A.M.-S.);[PERSON]RESS] (A.M.-S.);[EMAIL_ADDRESS] (A.M.-S.);[PERSON]RESS] (A.M.-S.);[EMAIL_ADDRESS] (A.M.-S.);[EMAIL_ADDRESS] (A.M.-S.);[PERSON]RESS] (A.M.-S.);[EMAIL_ADDRESS] (A.M.-S.);[EMAIL_ADDRESS] (A.M.-S.);[EMAIL_ADDRESS] (A.M.-S.);[PERSON]RESS] (A.M.-S.);[EMAIL_ADDRESS] (A.M.-S.);[EMAIL_ADDRESS] (A.M.-S.);[PERSON]RESS] (A.M.-S.);[EMAIL_ADDRESS] (A.M.-S.);[EMAIL_ADDRESS] (A.M.-S.);[PERSON]RESS] (A.M.-S.);[EMAIL_ADDRESS] (A.M.-S.);[PERSON]RESS] (A.M.-S.);[EMAIL_ADDRESS] (A.M.-S.);[EMAIL_ADDRESS] (A.M.-S.);[EMAIL_ADDRESS] (A.M.-S.);[EMAIL_ADDRESS] (A.M.-S.);[EMAIL_ADDRESS] (A.M.-S.);[PERSON]RESS] (A.M.-S.);[EMAIL_ADDRESS] (A.M.-S.);[EMAIL_ADDRESS] (A.M.-S.);[EMAIL_ADDRESS] (A.M.-S.);[EMAIL_ADDRESS] (A.M.-S.);[PERSON]RESS] (A.M.-S.);[EMAIL_ADDRESS] (A.M.-S.);[EMAIL_ADDRESS] (A.M.-S.);[EMAIL_ADDRESS] (A.M.-S.);[EMAIL_ADDRESS] (A.M.-S.);[EMAIL_ADDRESS] (A.M.-S.);[EMAIL_ADDRESS] (A.M.-S.);anna. The efficiency of the extraction of biologically active compounds from plant material depends on many factors, including the method of preparation and concentration of the material used for the extraction process, the selection of solvent and isolation techniques for active compounds, as well as the choice of extraction parameters (time or temperature, among others). Therefore, the optimisation of the process parameters is crucial to obtain the highest possible content of the desired active compounds in the extract [4]. One of the most frequently used methods for optimising plant material extraction processes is the response surface methodology (RSM). This optimisation tool allows for the identification of interdependencies between variables used in research, including those related to plant material extraction or food technology. The RSM develops an experimental design that integrates independent variables and uses input data from the experiment to generate a series of equations that can determine a theoretical value for the output. The outputs result from a well-designed regression analysis grounded in controlled independent variable values. As a result, based on the new values of the independent variables, the dependent variable can be predicted [5]. The use of mathematical modelling allows for a reduction in the number of experimental samples compared to the standard one-dimensional approach, which has a direct impact on reducing the final cost of the process, among other things, by limiting the consumption of energy or reagents [1; 6]. In addition to increasing the efficiency of laboratory testing, parameter estimation can help identify variables that significantly influence the model. To design an experiment in RSM, we can use, for example, the Box Behnken Design (BBD) and the Central Composite Design (CCD) [5]. The experimental points in the BBD are located on a hypersphere equidistant from the central point. In the CCD, we distinguish points of factorial design, axial points, and the central point [7]. The RSM-CCD model is successfully used in the optimisation of plant raw material extraction processes [8; 9; 10; 11]. _Sanguisorba officinalis_ L, called great burnet, is a plant belonging to the Rosaceae family. The most common raw material used in medicine is a root (_Sanguisorbae radix_). Because the aerial parts of _S. officinalis_ are also a valuable source of biologically active compounds, the leaves, flowers, and stalks are increasingly assessed for their health-promoting properties [12; 13; 14; 15].