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Juniperus thurifera is a native species to the mountains of the western Mediterranean region. It is used in traditional medicine as a natural treatment against infections. The present study aimed to carry out the chemical analysis and evaluate the antioxidant, antimicrobial, as well as in silico inhibition studies of the essential oils from Juniperus thurifera bark (EOEJT). Chemical characterization of EOEJT was done by gas chromatography (GC-MS). We have performed three antioxidant assays (Reducing power (FRAP), 2, 2-diphenylpicrylhydrazyl (DPPH), and total antioxidant capacity (TAC)) of the EOEJT. We next evaluated the antimicrobial activity against in silico study, which was carried out to help evaluate the inhibitory effect of EOEJT against NADPH oxidase. Results of the GC/MS analysis revealed seven major compounds in EOEJT wherein muurolol (36%) and elemol (26%) were the major components. Moreover, EOEJT possessed interesting antioxidant potential with an IC 50 respectively of 21.25 ± 1.02  μ g/mL, 481.02 ± 5.25  μ g/mL, and 271  μ g EAA/mg in DPPH, FRAP, and total antioxidant capacity systems. Molecular docking of EOEJT in NADPH oxidase active site showed inhibitory activity of α -cadinol and muurolol with a glide score of -6.041 and -5.956 Kcal/mol, respectively. As regards the antibacterial and antifungal capacities, EOEJT was active against all tested bacteria and all fungi, notably, against Escherichia coli K12 with an inhibition diameter of 21 mm and a MIC value of 0.67 mg/mL, as well as against Proteus mirabilis ATCC 29906 with an inhibition diameter of 18.33 ± 1.15 mm and a MIC value of 1.34 mg/mL. A more pronounced effect was recorded for the fungal pathogens Fusarium oxysporum MTCC 9913 with inhibition of 37.44 ± 0.28% and MIC value of 6.45 mg/mL, as well as against Candida albicans ATCC 10231 with an inhibition diameter of 20.33 ± 1.15 mm and a MIC value of 0.67 ± 0.00 mg/mL. Altogether, these results highlight the importance of EOEJT as a source of natural antibacterial and antioxidant drugs to fight clinically important pathogenic strains., Competing Interests: The authors declare that they have no conflicts of interest., (Copyright © 2022 Soufyane Lafraxo et al.)

Background: Artemisia negrei L. ( A. negrei ) is a medicinal and aromatic plant belonging to the family Asteraceae that is more widespread in the folded Middle Atlas Mountains, Morocco., Materials and Methods: This study was run to investigate the phytochemical composition and antioxidant, antibacterial, and antifungal activities of Artemisia negrei L. essential oil. This oil was extracted from the fresh plant material by using the Clevenger apparatus. The phytochemical composition was characterized by GC-MS. The antioxidant activity was evaluated using different methods including DPPH, β -carotene bleaching, and total antioxidant capacity. The antibacterial activity was tested vs. multidrug-resistant bacteria including both Gram-negative and Gram-positive using inhibition zones in agar media and minimum inhibitory concentration (MIC) bioassays. The antifungal activity was conducted on Candida albicans , Aspergillus niger , Aspergillus flavus, and Fusarium oxysporum using a solid medium assay., Results: The chromatographic characterization of essential oils of A. negrei revealed the presence of 34 compounds constituting 99.91% of the total essential oil. The latter was found to have promising antioxidant activity by all bioassays used such as DPPH, β- carotene bleaching, and total antioxidant capacity. The results obtained showed that our plant oils had potent antibacterial activity towards Gram-negative ( E. coli 57, E. coli 97, K. pneumonia , and P. aeruginosa) and Gram-positive ( S. aureus ), so that the maximum inhibition zones and MIC values were around 18-37 mm and 3.25 to 12.5 mg/mL, respectively. The oil also showed antifungal activity towards Candida albicans , Fusarium oxysporum, and Aspergillus Niger except for flavus species., Conclusion: The findings obtained in the work showed that A. negrei can serve as a valuable source of natural compounds that can be used as a new weapon to fight radical damage and resistant microbes., Competing Interests: The authors declare that they have no conflicts of interest., (Copyright © 2021 Khalid Chebbac et al.)