Phytochemical Investigation, Acute Toxicity, Central Analgesic and Antioxidant Activities of Extracts and Essential Oil of Cotula cinerea Del (Asteraceae)

Abstract

Background: Cotula cinerea belongs to the Asteraceae family and grows in desert areas such as Moroccan Sahara. The use of this plant in Moroccan traditional medicine prompted us to investigate its chemical composition, its acute oral toxicity, its analgesic and antioxidative activities. Methods: Extraction was conducted by steam distillation for essential oil and by maceration using solvents (hexane, ethyl acetate, n-butanol) for other non-volatile compounds. Quantitative analysis of total polyphenols, procyanidins and flavonoids was conducted through spectrophotometric assays. Qualitative phytochemical composition of the essential oil was investigated by GC/MS analysis. Acute oral toxicity was tested at a dose of 2000 mg/kg in mice. Central analgesic effect was assessed in rat using tail flick and hot plate models and the obtained results were compared to morphine. Antioxidant activity of the essential oil and the obtained extracts was evaluated through 2,2-diphenyl-1- picrylhydrazyl (DPPH°) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) assays and the obtained results were compared to TROLOX. Results: The obtained results showed that the studied extracts contained significant amounts of total polyphenols, flavonoids and condensed tannins. The phytochemical composition of the essential oil was predominated by thujone, eucalyptol and santolinatriene. The results of the acute oral toxicity showed that the tested essential oil and extracts were not toxic even at the highest dose of 2000 mg/kg. Experiments on analgesic activity showed that the administered extracts have a central analgesic effect. The highest effect was observed with the n-butanol and ethyl acetate extracts for both tail-flick and hot plate tests. The antioxidant activity of the explored extracts showed higher scavenging activities of the studied samples compared to TROLOX. Conclusion: Our results indicate thus that C. cinerea could be considered as a source of various secondary metabolites including terpenoids and polyphenols. Exploration of its biological activities showed that the plant essential oil and extracts possessed antioxidant and analgesic effects. Based on the results of this study, it is likely that extracts of C. cinerea could open perspectives for its use for pain relief.

Ethnobotanical and ethnomedicinal analysis of wild medicinal plants traditionally used in Naâma, southwest Algeria

“…Recent studies revealed that this plant exhibits various biological activities such as analgesic, cytotoxic, and effect on diabetes. These are related to the presence of chemical substances such as flavonoids, terpenes, and essential oils which are predominated by thujone, eucalyptol, and santolinatriene (Amssayef and Eddouks 2020;Guaouguaou et al 2020). It have been reported that a single and repeated oral administration of Brocchia cinerea (Delile) Vis aqueous extract at the dose of 20 mg/kg for 15 days, reduced significantly blood glucose and plasma triglycerides levels in both normal and diabetic rats (Amssayef and Eddouks 2020).…”

Structural characterization of bioactive compounds in Cotula cinerea extracts by ultra‐high‐performance liquid chromatography with photodiode array and high‐resolution time‐of‐flight mass spectrometry detectors

“…The AcOEt extract was dominated by kaempferol and chrysosphenol isomer derivatives with 33.68 and 44.21%, respectively, while the n‐BuOH extract contained sulfated flavonoids as major compounds with the glycosylated and free sulfated kaempferol derivatives at 33.78 and 25.35%, respectively. The presence of these compounds could explain at least in part the biological activities recently reported in the Cotula cinerea extracts …”

“…From a phytochemical point of view, Cotula cinerea was reported to contain a wide range of phytochemical compounds such as saponins, alkaloids, phenolic acids, tannins, flavonoids, steroids, and terpenoids . Although the phytochemical and the biological activities of Cotula cinerea have been reported in previous studies, the secondary metabolites of the Moroccan plant have not been thoroughly investigated and will be explored in the present work.…”