Chemical composition, free radicals, pathogenic microbes, α-amylase and α-glucosidase suppressant proprieties of essential oil derived from Moroccan Mentha pulegium: in silico and in vitro approaches

Abstract

Several bioactive phytochemicals found in herbal products, particularly in essential oils (EOs), are proved to be vital in the prevention of chronic illnesses including infectious and metabolic disorders. The aim of this study was, firstly to identify the phyto-chemical composition and assess, in vitro, the antioxidant and antimicrobial properties of Mentha pulegium EO, and secondly, to evaluate its potential antidiabetic effects, in silico. GC-MS analysis was employed for the examination of EO phytochemical composition. The antioxidant capacity was evaluated by the ferric reducing antioxidant power (FRAP) assay, the scavenging of free (DPPH) radicals, and the examination of total antioxidant capacity (TAC). The antimicrobial efficacy against pathogenic Gram-negative and Gram-positive bacteria as well as Candida albicans was evaluated through the determination of minimal inhibitory (MIC), bactericidal (MBC), and fungicidal (MFC) concentrations, alongside the utilization of disc diffusion techniques. By use of molecular docking antidiabetic potential of pennyroyal EO was also tested. The analysis revealed a total of thirteen components in M. pulegium EO, with pulegone (72.05%) being the major component, followed by 8-hydroxy-p-menthan-3-one (5.97%) and imidazolidine (3.23%). Pennyroyal EO displayed a notable antioxidant potential, as assessed by FRAP and DPPH assays, marking an EC₅₀ and IC₅₀ values of 26.500 ± 0.200 mg/mL and 054.630 ± 1.350 mg/mL, correspondently. The examined EO also possessed a total antioxidant capacity of 52.610 ± 4.734 mg AAE/g EO. The findings of antimicrobial test showed a notable efficacity of M. pulegium EO against S. aureus (MIC = MBC = 3.058 mg/mL), E. coli (MIC = 6.076 mg/mL / MBC = 6.125 mg/mL) and C. albicans (MIC = MBC = 3.063 mg/mL). Regarding the antidiabetic potential, in silico analysis identified imidazolidine as the most active molecule against the α-glucosidase (PDB: 5NN8) and the α-amylase (PDB: 1B2Y) enzymes marking glide scores of -8.393 and -7.172 kcal/mol, correspondently. These findings suggest that the EO derived from Moroccan M. pulegium holds promise as a potent natural remedy against free radicals and resistant pathogenic microbes. Moreover, it shows potential as a promising solution for managing diabetes disorders.