RESUMEN
Abstract: In this article, we report a study of assay of sesquiterpene lactones (alantolactone, isoalantolactone) in plant extraction derived by ultrasound-assisted extraction, оrthogonal test design and reflux extraction from medicinal plant’s composition (Salsola laricifolia turcz.e litv+Inula helenium). High-performance liquid chromatography (HPLC) method was used for determination of the contents of alantolactone and isoalantolactone in the investigated extracts. The result shown that the amount of alantolactone was 0.64±0.03%, and isoalantolactone 0.59±0.01% in the plant extraction derived by reflux condensation extraction. Key words: Alantolactone, Isoalantolactone, HPLC, Salsola laricifolia turcz.ex litv, Inula helenium, Reflux method, Ultrasound- assisted extraction.