Do Mai Nguyen Phuong et al. 2026. INVESTIGATION OF SOME FACTORS AFFECTING THE EXTRACTION OF POLYPHENOL AND FLAVONOID COMPOUNDS FROM Ruellia tuberosa L. HUIT Journal of Science. 26, 1 (Feb. 2026), 25–36. DOI:https://doi.org/10.62985/j.huit_ojs.vol26.no1.382.