Abstract
Plant polyphenols represent an important group of bioactive compounds known for their pronounced antioxidant properties. These compounds are capable of neutralizing free radicals, reducing oxidative stress, and preventing the development of chronic diseases, including cardiovascular, neurodegenerative, and inflammatory conditions. The aim of the present study was to compare the efficiency of different extraction methods for polyphenols from three medicinal plants: sweet clover (Melilotus officinalis), St. John’s wort (Hypericum perforatum), and purslane (Portulaca oleracea). The study evaluated three extraction techniques: maceration, percolation using a Soxhlet apparatus, and an environmentally friendly method involving the use of curd whey as a natural solvent. Optimal parameters such as temperature, liquid-to-solid ratio (hydromodule), and extraction time were thoroughly investigated and adjusted. Experimental results demonstrated that the highest yield of phenolic compounds was achieved through the percolation method using 70% ethanol. Although the use of curd whey resulted in a lower polyphenol yield, it offers ecological advantages and is suitable for integration into alcohol-free food technologies. The findings of this study may be applied in the development of functional food products and natural antioxidant additives with enhanced biological activity, as well as in the pharmaceutical and nutraceutical industries