Antioxidant Activities of Satureja hortensis L. Essential Oil during the Flowering Period

Abstract:

Objective: This study was conducted to investigate the changes of total phenolic concentration and antioxidant activity of Satureja hortensis L. during the flowering stage cultivated under the ecological conditions of Rize, Turkey. Material and Methods: The plantation was established with natural cuttings of Satureja hortensis L. Cuttings were obtained at three stages (pre-flowering, full flowering, and post-flowering) and dried in an oven at 35°C. The analysis of essential oil in the leaves and flowers of the samples was carried out using a Clevenger aparatus for three hours. The total phenolics and antioxidant activity of essential oils was evaluated by Folin-Ciocalteu and DPPH free radical scavenging assays, respectively. Results: The total phenolic content varied between 746 ± 4 and 1087 ± 44 μM, and the highest value was obtained from the full-flowering stage. The SC₅₀ values in the DPPH assay ranged from 6.65 ± 0.38 to 16.10 ± 0.99 μM catechin equivalent and the highest activity was observed in the full flowering stage. Among all the samples, the essential oil of the cutting taken during the full flowering period showed the highest phenolic concentration and antioxidant activity. Conclusion: Satureja hortensis L. is a good natural antioxidant source with its high phenolic concentration and antioxidant activity.

Key words: Satureja hortensis L, antioxidant activity, essential oil, polyphenol content, harvest times.