Acute toxicity and anti-inflammatory activity of essential oils of Cotula cinerea from southwest Algeria

This work deals with the biological activity of the essential oils of an Algerian plant (Cotula cinerea) which belongs to the Asteraceae family. The study was carried out in the south-west of Algeria. We chose essential oils which are natural substances thanks to their numerous anti-infectious, antioxidant and antibacterial properties, etc. The objective of this work is to study the acute toxicity as well as the evaluation of the anti-inflammatory properties of the essential oils of both organs (leaves and flowers) of Cotula cinerea. As methodological approaches, we used the hydrodistillation technique to obtain the essential oils from leaves and flowers. Thus, the acute toxicity was determined by Lorke's method and the anti-inflammatory activity was evaluated by measuring the plantar oedema of mice induced by carrageenan. The results show that the essential oil extracts of the leaves and flowers are low toxic substances with LD50s of 1131.37 mg/kg and 1264.91 mg/kg respectively. They also show a considerable anti-inflammatory effect at doses not exceeding 300 mg/kg with maximum percentages of 86.16% for leaves and 80.87% for flowers. These results show the efficacy of the essential oils of this plant and their therapeutic richness which can be used in traditional medicine for anti-inflammatory treatment. This study has provided additional knowledge on the biological activity of Cotula cinerea essential oils and has opened perspectives for the research of the active principles contained in this species as well as the application of biotechnology to know the molecular mechanism and valorise this natural wealth.