VARIATIONS OF THE CHEMICAL COMPONENTS AND BIOLOGICAL ACTIVITIES OF THYMUS CAPITATUS ESSENTIAL OIL FROM THREE REGIONS IN PALESTINE
An Najah National University
Introduction: In Palestinian traditional medicine, Thymus capitatus is a widely utilized medicinal plant. The main goal of this study was to assess the phytochemical content of T.capitatus essential oils (EOs) from three Palestinian regions using hydro distillation and microwave ultrasonic technologies. Also, the essential oil that was taken from the plant was put through some biological tests. Methodology: identification and quantification of the various elements in the EOs examined were accomplished using GC-MS spectrometry. The DPPH assay and the β-carotene-linoleic acid assay were utilized in order to determine the levels of antioxidant activity. In order to determine whether or not T.capitatus possesses anti-lipase activity. α-amylase inhibitory activity of the EOs samples was studied in comparison with the hypoglycemic drug, Acarbose. An anti-microbial assay was conducted against seven different types of the most common bacteria and fungi. Additionally, Hep-G2 cells were used to assess the anticancer activity. Results: The EOs presented several components, mainly monoterpenes, thymol and carvacroal. Chemical components of the EOs varied between districts (Ramallah: carvacrol (31.25%), γ-terpinene (30.94%), Jenin: γ-terpinene (67%), cis-b-terpineol (12.91%), Hebron: thymol (40.35%), b-Caryophyllene (13.23%) were the main components of the EOs in the districts). According to the results, the antioxidant activity of T.capitatus EOs was shown to be high and dose dependent. DPPH assay results showed that the three districts had nearly the same IC50, which was a fourth-fold of gallic acid. On the other hand, β-carotene-linoleic acid assay results showed that all samples had higher antioxidant efficiency than water (control) and the synthetic antioxidant α-tocopherol, which gave the highest β-carotene degradation. T.capitatus EO worked against all bacteria and fungi that were tested in terms of antibacterial activity, with MIC values between 0.1953 and 1.5625 μg/ml. The Hebron sample gave distinguishable results at low concentrations. All samples showed anti-lipase activity even higher than Orlistat at concentrations equal to or higher than 200 g/ml. Furthermore, all three EO samples inhibited α-amylase concentration dependently; statistical analysis revealed a slight difference between the samples, but all of them showed nearly the same percent inhibition at 400 g/ml, which is 50% acarbose. Finally, according to cytotoxic activity, all samples showed promising results against Hep-G2, with an average percent inhibition of 85% at a concentration of 62.5 μg/ml with slight differences between the districts. Conclusion: The chemical structure of the EO of T.capitatus can be related to the plant's origin, soil components, genetic variables, and climatic conditions, which in turn reflect on the biological activity of it.
Thymus capitatus , hydro distillation , thymol, carvacrol , , anti-lipase, DPPH