title: Simplified procedure of silymarin extraction from Silybum marianum L. Gaertner.
abstract: Silymarin, a mixture of flavonolignans exhibiting many pharmacological activities, is obtained from the fruits of milk thistle (Silybum marianum L. Gaertner). Due to the high lipid content in thistle fruits, the European Pharmacopoeia recommends a two-step process of its extraction. First, the fruits are defatted for 6 h, using n-hexane; second, silymarin is extracted with methanol for 5 more hours. The presented data show that this extremely long traditional Soxhlet extraction process can be shortened to a few minutes using pressurized liquid extraction (PLE). PLE also allows to eliminate the defatting stage required in the traditional procedure, thus simplifying the silymarin extraction procedure and preventing silymarin loss caused by defatting. The PLE recoveries obtained under the optimized extraction conditions are clearly better than the ones obtained by the Pharmacopoeia-recommended Soxhlet extraction procedure. The PLE yields of silychristin, silydianin, silybin A, silybin B, isosilybin A and isosilybin B in acetone are 3.3, 6.9, 3.3, 5.1, 2.6 and 1.5 mg/g of the non-defatted fruits, respectively. The 5-h Soxhlet extraction with methanol on defatted fruits gives only ∼72% of the silymarin amount obtained in 10 min PLE at 125°C.
authors.affiliation: Faculty of Chemistry, Department of Chromatographic Methods, Maria Curie-Sklodowska University, Pl. Maria Curie-Sklodowska 3, Lublin 20-031, Poland dorota.wianowska@poczta.umcs.lublin.pl.
authors.forename: Dorota
authors.initials: D
authors.lastname: Wianowska
authors.affiliation: Faculty of Chemistry, Department of Chromatographic Methods, Maria Curie-Sklodowska University, Pl. Maria Curie-Sklodowska 3, Lublin 20-031, Poland.
authors.forename: Mariusz
authors.initials: M
authors.lastname: Wiśniewski
mesh_terms: D000096:Acetone / Q000737:chemistry; D002851:Chromatography, High Pressure Liquid; D006586:Hexanes / Q000737:chemistry; D059625:Liquid-Liquid Extraction / Q000379:methods*; D020944:Silybum marianum / Q000737:chemistry*; D012838:Silymarin / Q000032:analysis / Q000737:chemistry* / Q000302:isolation & purification*; D012997:Solvents / Q000737:chemistry; D013696:Temperature
chemical_list: D006586:Hexanes; D012838:Silymarin; D012997:Solvents; D000096:Acetone