title: Optimized ultrasonic assisted extraction-dispersive liquid-liquid microextraction coupled with gas chromatography for determination of essential oil of Oliveria decumbens Vent.
abstract: Ultrasonic assisted extraction-dispersive liquid-liquid microextraction (UAE-DLLME) coupled with gas chromatography (GC) was applied for extraction and determination of essential oil constituents of the plant Oliveria decumbens Vent. Scanning electron microscopy (SEM) was used to see the effect of ultrasonic radiation on the extraction efficiency. By comparison with hydrodistillation, UAE-DLLME is fast, low cost, simple, efficient and consuming small amount of plant materials (∼1.0 g). The effects of various parameters such as temperature, ultrasonication time, volume of disperser and extraction solvents were investigated by a full factorial design to identify significant variables and their interactions. The results demonstrated that temperature and ultrasonication time had no considerable effect on the results. In the next step, a central composite design (CCD) was performed to obtain the optimum levels of significant parameters. The obtained optimal conditions were: 0.45 mL for disperser solvent (acetonitrile) and 94.84 μL for extraction solvent (chlorobenzene). The limits of detection (LODs), linear dynamic range and determination coefficients (R(2)) were 0.2-29 ng mL(-1), 1-2100 ng mL(-1) and 0.995-0.998, respectively. The main components of the essential oil were: thymol (47.06%), carvacrol (23.31%), gamma-terpinene (18.94%), p-cymene (8.71%), limonene (0.76%) and myristicin (0.63%).
authors.affiliation: School of Chemistry, University College of Science, University of Tehran, Tehran, Iran. sereshti@khayam.ut.ac.ir
authors.forename: Hassan
authors.initials: H
authors.lastname: Sereshti
authors.forename: Yahya
authors.initials: Y
authors.lastname: Izadmanesh
authors.forename: Soheila
authors.initials: S
authors.lastname: Samadi
mesh_terms: D000081248:Allylbenzene Derivatives; D000704:Analysis of Variance; D019661:Apiaceae / Q000737:chemistry*; D001593:Benzyl Compounds / Q000032:analysis; D005591:Chemical Fractionation / Q000379:methods*; D002849:Chromatography, Gas / Q000379:methods*; D004148:Dioxolanes / Q000032:analysis; D016014:Linear Models; D039821:Monoterpenes / Q000032:analysis; D009822:Oils, Volatile / Q000737:chemistry*; D010936:Plant Extracts / Q000737:chemistry*; D010938:Plant Oils / Q000737:chemistry*; D011748:Pyrogallol / Q000031:analogs & derivatives / Q000032:analysis; D012680:Sensitivity and Specificity; D012997:Solvents; D013010:Sonication
chemical_list: D000081248:Allylbenzene Derivatives; D001593:Benzyl Compounds; D004148:Dioxolanes; D039821:Monoterpenes; D009822:Oils, Volatile; D010936:Plant Extracts; D010938:Plant Oils; D012997:Solvents; D011748:Pyrogallol; C005246:myristicin