title: Multivariate optimization of hydrodistillation-headspace solvent microextraction of thymol and carvacrol from Thymus transcaspicus.
abstract: In this paper multivariate response surface methodology (RSM) has been used for the optimization of hydrodistillation-headspace solvent microextraction (HD-HSME) of thymol and carvacrol in Thymus transcaspicus. Quantitative determination of compounds of interest was performed simultaneously using gas chromatography coupled with flame ionization detector (GC-FID). Parameters affecting the extraction efficiency were assessed and the optimized values were 5 min, 2 microL and 3 min for the extraction time, micro-drop volume and cooling time after extraction, respectively. The amounts of analyte extracted increased with plant weight. The calibration curves were linear in the ranges of 6.25-81.25 and 1.25-87.50 mg L(-1) for thymol and carvacrol, respectively. Limit of detection (LOD) for thymol and carvacrol was 1.87 and 0.23 mg L(-1), respectively. Within-day and between-day precisions for both analytes were calculated in three different concentrations and recoveries obtained were in the range of 89-101% and 95-116% for thymol and carvacrol, respectively.
authors: Department of Phytochemistry, Medicinal Plants and Drugs Research Institute, Shahid Beheshti University, G. C., Evin, Tehran, Iran.
authors: Vahid
authors: V
authors: Kiyanpour
authors: Ali Reza
authors: AR
authors: Fakhari
authors: Reza
authors: R
authors: Alizadeh
authors: Behvar
authors: B
authors: Asghari
authors: Mehdi
authors: M
authors: Jalali-Heravi
mesh_terms: D005591:Chemical Fractionation / Q000379:methods*; D002849:Chromatography, Gas; D000081007:Cymenes; D019686:Lamiaceae / Q000737:chemistry*; D039821:Monoterpenes / Q000032:analysis / Q000302:isolation & purification*; D015999:Multivariate Analysis; D015203:Reproducibility of Results; D012997:Solvents / Q000737:chemistry*; D013943:Thymol / Q000032:analysis / Q000302:isolation & purification*
chemical_list: D000081007:Cymenes; D039821:Monoterpenes; D012997:Solvents; D013943:Thymol; C073316:carvacrol