Research on the phenolic compounds and antioxidant activities of Tunisian Thymus capitatus

Abstract Thymus capitatus flowers phenolic compounds was studied by reversed-phase high-performance liquid chromatography. Total phenolic content, total flavonoid content and condensed tannins content of thyme flowers extracts were of 15.06 ± 0.73 mg GAE/g DW, 10.62 ± 0.24 mg CE/g DW and 0.66 ± 0.06 mg CE/g DW, respectively. HPLC analysis indicated that phenolic acids (56.86 ± 0.31%, 6.80 ± 0.48 mg/g) constitute the main phenolic class, followed by phenolic monoterpenes (27.93 ± 0.13%, 3.34 ± 0.11 mg/g) and flavonoids (12.54 ± 0.31%, 1.50 ± 0.15 mg/g). Thymol, ferulic and gallic acids were the most abundant phenolic compounds with proportions of 27.93 ± 0.13% (3.34 ± 0.11 mg/g), 14.59 ± 0.13% (1.74 ± 0.05 mg/g) and 14.25 ± 0.31% (1.70 ± 0.03), respectively. Antioxidant activities of methanolic extracts of thyme flowers were evaluated. Our findings demonstrated that methanolic extracts possess significant antioxidant activities and may be suggested as a new potential source of natural antioxidant.