Essential oils of Origanum compactum Benth: Chemical characterization, in vitro, in silico, antioxidant, and antibacterial activities

Abstract

This study was performed to investigate the phytochemical profile, and the, in vitro, and, in silico, antioxidant and antibacterial properties of the essential oil (EO) extracted from Origanum compactum. EO phytochemical screening was examined by gas chromatography coupled to mass spectrometry. The antioxidant potential, in vitro, was assessed using reducing power(FRAP), free 2,2 diphenylpicrylhydrazyl (DPPH) radical scavenging and total antioxidant capacity tests. Antibacterial properties against two Gram (−) and two Gram (+) bacteria were assessed using the minimal inhibitory concentration (MIC) and the disc diffusion methods. By use of molecular docking, antioxidant and antibacterial activities of oregano EO were also tested. Thymol (75.53%) was the major compound among the nine compounds identified in the EO of Origanum compactum, followed by carvacrol (18.26%). Oregano EO showed an important antioxidant capacity, as tested by FRAP and DPPH assays, with EC50 and IC50 values of 13.300 ± 0.200 and 0.690 ± 0.062 mg/mL, respectively. The same EO has a total antioxidant capacity of 173.900 ± 7.231 mg AAE/g EO. The antibacterial results showed significant activity of Origanum compactum EO against all tested bacteria, especially against S. aureus (MIC = 0.25 mg/mL) and B. subtilis (MIC = 0.06 mg/mL). In silico, carvacrol was the most active molecule against nicotinamide adenine dinucleotide phosphate oxidase (2CDU) and S. aureus nucleoside diphosphate kinase (3Q8U) with a glide score of −6.082, and −6.039 kcal/mol, respectively. Regarding the inhibition of E. coli beta-ketoacyl-[acyl carrier protein] synthase (1FJ4), piperitenone was the most active molecule with a glide score of −7.112 kcal/mol. In light of the results obtained, the EO of Origanum compactum Moroccan species can be used as promising natural food conservatives and an agent to fight antibiotic-resistant nosocomial microbes.

A Review on Reinforcements and Additives in Starch-Based Composites for Food Packaging

“…Carvacrol (Figure 17), a phenol, is the primary component of oregano and thyme essential oils, with a range of 5 to 50% for thyme [295] and between 18-71% in the case of oregano [300,301]. These variances can be due to the different extraction techniques and the parts of the plant that were utilized to extract the molecules.…”

Phytochemical Composition, Antibacterial and Antifungal Activities of Essential Oil of Juniperus phoenicea from Fez-Meknes Region, North Central Morocco

“…The MIC and MBC were evaluated according to the method previously described, 20,21 with slight modifications. Each well of a 96well microplate was filled with 100 μL of Mueller-Hinton growth medium (MHB), then 100 μL of EO diluted in DMSO (40% v/v) was added to the first well, and a microdilution was done by transferring 100 μL from the first well to the next well, and so on, to obtain concentrations ranging from 80 to 0.67 mg/mL.…”

Exploring the Bioactive Compounds in Some Apple Vinegar Samples and Their Biological Activities

“…A total of 25 mL of each vinegar sample was combined with 1 mL of the reagent solution (28 mM sodium phosphate, 0.6 M sulfuric acid, and 4 mM ammonium molybdate). The mixture was incubated for 90 min at 95 • C, and the absorbance was measured at 695 nm in comparison to a blank [63]. The total antioxidant capacity was measured using the ascorbic acid calibration curve and expressed as milligrams of ascorbic acid equivalent per gram of vinegar (mg AAE/g of vinegar).…”

“…In this test, the microdilution method was used to evaluate the MICs [63]. Serial dilutions of the vinegar samples were prepared directly in a 96-well microplate containing MHB and YPG broth to obtain different concentrations.…”