Volatile oil yield and composition, total phenolic content, antioxidant activity and secondary metabolite content of collected thymus praecox species in Rize

Abstract

In this study, the volatile oil yield (Clevenger), volatile oil (VO) composition (Gas Chromatography), phenolic contents (UV-VIS Spectrophotometer), antioxidant activities (UV-VIS Spectrophotometer) and secondary metabolite content (High Pressure Liquid Chromatography) of 11 Thymus praecox subspecies were evaluated. The most detected chemical class were oxygenated monoterpenes (55.18-86.1 %) in investigated samples. In the present study rosmarinic acid, isoquercitrin, gallocatechin and thymol could be detected in high amounts. The min. and max. content values of Flora/Field Samples were 1543.241 and 890.3-1425.3 for rosmarinic acid, 139.44-287.894 and 129.9-312.2 for thymol, 38.619-121.424 and 26.3-112.9 for gallocatechin as mg/g DW. Principal Component Analysis was used to differentiate Thymus praecox species regarding volatile oil composition and secondary metabolite content. The results demonstrated that T. praecox collected from the Rize flora and cultivated afterwards showed variability based on investigated characteristics. Finally, the Thymus praecox samples displaying high bioactive compounds present useful information for further investigations and applications.