title: Ultrasonically assisted extraction of total phenols and flavonoids from Rhodiola rosea.
abstract: This work deals with ultrasonically assisted extraction (UAE) of biologically active compounds from rhizomes of Rhodiola rosea, a popular medicinal plant. The influence of temperature, type of solvent and solid/solvent ratio on the yield of total extracts, total phenols and flavonoids was established. The best extraction of total phenols and flavonoids was achieved by using 50% aqueous EtOH and MeOH, respectively. Five times increase of solid/solvent ratio (from 1:20 to 1:100 (w/v)) leads to slow increase of the yield of total phenols and flavonoids. The extraction effectiveness of conventional maceration with 50% EtOH and UAE performed for 1 h at 25 degrees C using the same solvent with respect of total phenols was comparable.
authors.affiliation: Institute of Organic Chemistry with Centre of Phytochemistry, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria. staneva@orgchm.bas.bg
authors.forename: Jordanka
authors.initials: J
authors.lastname: Staneva
authors.forename: Milka
authors.initials: M
authors.lastname: Todorova
authors.forename: Neyko
authors.initials: N
authors.lastname: Neykov
authors.forename: Ljuba
authors.initials: L
authors.lastname: Evstatieva
mesh_terms: D002138:Calibration; D000431:Ethanol; D005419:Flavonoids / Q000737:chemistry* / Q000302:isolation & purification; D000432:Methanol; D010636:Phenols / Q000737:chemistry* / Q000302:isolation & purification; D010936:Plant Extracts / Q000737:chemistry; D029771:Rhodiola / Q000737:chemistry*; D012997:Solvents; D013056:Spectrophotometry, Ultraviolet; D014465:Ultrasonics
chemical_list: D005419:Flavonoids; D010636:Phenols; D010936:Plant Extracts; D012997:Solvents; D000431:Ethanol; D000432:Methanol