Metabolite profiling, anti-inflammatory, analgesic potentials of edible herb Colocasia gigantea and molecular docking study against COX-II enzyme

Abstract

Ethnopharmacological relevance: Consumable herbs play a basic part in sustenance and human health. Traditionally, Colocasia gigantea Hook (Araceae) is used to treat fever, infection, wounds healing, drowsiness, tuberculosis, stomach problems etc. AIM OF THE STUDY: The study aspired to identify bioactive compounds, to evaluate anti-inflammatory and analgesic potentials of edible herb C. gigantea, and to molecular docking study against anti-inflammatory enzyme Cyclooxygenase-2 (COX-2).

Materials and methods: Chemical components of C. gigantea were discerned by HPLC and GCMS assays. In vitro anti-inflammatory activity was appraised by heat-induced, hypotonicity, and hydrogen peroxide-induced hemolysis assays and in vivo by formalin-induced paw edema assay. In vivo analgesic activity was evaluated by acetic acid-induced pain modulation assay. Also, molecular docking of the identified compounds was explored against the anti-inflammatory enzyme cyclooxygenase-2.

Results: HPLC-DAD analysis divulged the presence of trans-cinnamic acid along with (-)-epicatechin as a prime component. Also, 9, 12-Octadecadienoic acid (37.86%) and n-Hexadecanoic acid (25.89%) as the major as well as 24 other compounds were confirmed through GCMS in the extract. In in vitro anti-inflammatory study, C. gigantea extract indicated prominent erythrocyte membrane stabilization activity with good percentage aegis in all experimental assays. In addition to, formalin-induced in vivo anti-inflammatory assay revealed the maximum (42.37% and 48.72%) suppression of edema at the fourth hour at 250 and 500 mg/kg body weight, respectively. Moreover, an in-vivo pain modulation assay exposed significant (p < 0.05) activity at experimental doses. Furthermore, in the docking study, (-)-epicatechin was more active rather than other identified compounds with strong binding affinity to COX-2 protein.

Conclusions: The extract evinced remarkable anti-inflammatory and analgesic activities. Identified bioactive components along with other components of the extract might play a pivotal role in the observed bioactivity and the results vindicate the use of edible herb C. gigantea in ancestral medicine.

Keywords: 9,12-Octadecadienoic acid; Cyclooxygenase-II; GCMS; HPLC; Molecular docking; Trans-Cinnamic acid.