Akebia trifoliate koiaz peels extract as environmentally benign corrosion inhibitor for mild steel in HCl solutions: Integrated experimental and theoretical investigations

•Eco-friendly pectin components were extracted from akebia trifoliate koiaz peels.•The extract showed 90% inhibition efficiency for mild steel corrosion in HCl medium.•Electrochemical investigations suggest a protective barrier formation at the solution/steel interface.•Adsorption of inhibitor on the steel surface follows the Langmuir isotherm.•Molecular simulation was used for interpreting the inhibition phenomena.