VALIDATION OF A HIGH PERFORMANCE LIQUID CHROMATOGRAPHY TECHNIQUE FOR THE INVESTIGATION OF THYMOL AND CARVACROL IN THYMUS SERPYLLUM L. INDIGENOUS TO BALOCHISTAN

Thymus serpyllum L. belonging to the family Lamiaceae, is a popular therapeutic plant which contains ingredients such as thymol and carvacrol which has been generally utilized in various pharmaceutical products . Thymol and carvacrol are mostly analyzed by gas chromatography (GC) method however, in this project validation of a high performance liquid chromatography (HPLC) technique used and developed for the quantification of thymol and carvacrol in Thymus serpyllum L. Thymus oil of the herbal plant was quantified by the GC and HPLC methods. The HPLC method selected with Hypersil ODS C 8 (250 X 4.6mm) column and an isocratic acetonitrile: water: orthophosphoric acid (60:38:2) used as mobile phase which was set at a flow rate of 1.5 ml/minute. The analytical method was used for linearity, selectivity (r2>0.997), for thymol and carvacrol The limit of detection (LODs) and limit of quantification (LOQs) were analyzed to be 0.015, 0.050 µg/ml and 0.5 , 1.9 µg/ml for thymol and carvacrol respectively. The precision (inter day 3.3-3.6, 3.9-4.3) and (intraday 1.1-1.8, 1.8-2.8) and recovery (98.1%, 97.2%) for thymol and carvacrol respectively. The quantity of thymol and carvacrol in thymus oil observed by HPLC (8.3%, 3.03%) and GC (7.7%, 2.95 %) were observed by statistical analysis and they found good result. Keywords: Carvacrol, HPLC, GC, Thymus serpyllum L., method Validation