ANTIOXIDANT ACTIVITIES OF SOME LAMIACEAE HERBS FROM IRAQI AND TURKISH ORIGIN: A COMPARATIVE

Dhamair Jasim Sultan Al-Khazrai, Gulnur Arabaci*, Nawar Imad Ahmed Ahmed

This work aims to compare and evaluate the in-vitro antioxidant properties of Lamiaceae herbs, rosemary salvia (Rosmarinus officinalis L.), sage (Salvia officinalis L.) and marjoram (Origanum majorana L.) from Iraq and Turkey. Oxidative stress is implicated in many chronic and degenerative disorders processes and consequently, antioxidants have received considerable scientific attention in recent years as potential contributors to the inhibition of free radical propagation and the limitation of oxidative damage. Plant materials, especially medicinal and aromatic herbs are often sources of various phytochemicals with antioxidant properties such as phenolics acids, flavonoid compounds, terpenoids, and other bioactive compounds. That can act as metal-chelating, free radical-scavenging or reducing agents. Methodology: Aerial parts were dried and extracted with ethanol. For analysis of total phenolic content (TPC), total flavonoids content (TFC), DPPH radical-scavenging ability, reducing power and Fe- chelating activity. Results: Turkish S. rosmarinus presented higher values for TPC (2.36 0.06 mg GAE/g dry extract) with up to 100.0 3.8% inhibition of DPPH at 500 µg/mL. Turkish O. majorana had the highest TFC (0.0720 ± 0.0028mg QE/g dry extract) and the best reducing power amongst extracts 1.99 ± 0.10. The absorbance at 700 nm at 500 µg/mL). The strongest Fe chelating activity was exhibited by S. Officinalis from Iraq at 300 µg/mL (97.0 3.2%) followed by O.  majorana from Iraq which presented higher values at 500 µg/mL (98.3 9.2%). Our data strongly indicate that there are differential and complementary antioxidants-related chemicals responsible for the tested activities in the selected Lamiaceae species from Iraq and Turkey depending on plant species, origin, concentration and assay system. These findings provide a valuable basis for advanced biochemical, phytochemical, and pharmaceutical investigations of these herbs.