Composition and antioxidant activity of Abies marocana essential oil

Abstract

Belonging to the Pinaceae family Abies marocana is a native tree from calcareous mountains of Jebala in northern Morocco. This endemic species is distributed over Mont Tazaout and Talassemtane in the province of Chefchaouen. The present study explores for the first time the phytochemical composition, physicochemical properties, total phenolic content (TPC) and molecular docking simulations to evaluate antioxidant activity of Mont Tazaout Abies marocana essential oil (AMEO). AMEO was extracted using steam distillation, with a yield of 0.24%. A total of 49 compounds were identified using gas-chromatography coupled with mass spectrometry (GC/MS) method. Monoterpene hydrocarbons (88.55%) being the dominant class, and the main components of the tested oil were limonene (38.46%), α-Pinene (21.16%), β-Pinene (12.92%) and camphene (11.23%). Physicochemical properties of AMEO were determined, including density (0.888 ± 0.020) g/cm3, refractive index (1.470 ± 0.010), and optical rotation (-40.52 ± 0.04)˚. Furthermore, the total phenolic content (TPC) of the essential oil was found to be (5.07 ± 0.49) mg GAE/g EO. AMEO shows an IC50 = (136.28 ± 7.8) mg/mL and IC50 = (1.47 ± 0.04) mg/mL in the DPPH and FRAP assays, respectively. Molecular docking used to investigate the mechanism of interaction between the constituents of AMEO and target proteins associated with antioxidant activity. After analyzing the docking results related to the docking of the seven studied compounds (S-limonene, R-limonene, camphene, (+)-α-pinene, (-)-α-pinene, (+)-β-pinene and (-)-β-pinene), compounds R-limonene and S-limonene emerged as the most promising antioxidants. This is due to their favorable binding profiles with both NAD(P)H oxidase and nitric oxide synthase targets. These findings highlight the potential bioactive properties of AMEO, suggesting its relevance for further exploration in pharmaceutical, cosmetic and medicinal food reformulation.