No abstract

No abstract

The chemical composition of essential oil isolated from Chrysanthemum fontanesii and C. coronarium by hydrodistillation, was analysed by GC and GC/MS. A total 66 compounds representing 97.9% of the oil were identified in C. fontanesii, and 44 components representing 97.2% of the total oil in C. coronarium. The chemical composition of C. fontanesii and C. coronarium, is very different, the only common components are α-pinene, βpinene, myrcene and Δ3-carene. The Essential oil of C. fontanesii and C. coronarium was tested for antibacterial activity against nine bacteria strains. The oil showed modest effect against Staphylococcus aureus ATCC 25923, and it has no significant antibacterial activity against the other bacteria tested. The population of C. fontanesii studied showed a diploid chromosome number 2n = 2x = 18 and a tetraploid 2n = 4x = 36 for C. coronarium.

Background: Over the past decade, most antibiotic research programs have focused on finding new compounds with antimicrobial activity. This study aims to investigate the chemical composition and antibacterial activity of the essential oil (EO) extracted from ripe berries of Algerian Juniperus thurifera var. aurasiaca. Methods: The chemical composition of J. thurifera EO extracted by hydrodistillation was analyzed by using the GC-MS technique. Antibacterial activity of EO alone and in combination with three conventional antibiotics was assessed by using disc diffusion method against four bacterial strains. Results: Thirty-five components were identified, representing ~87 % of the oil. The main components were m-mentha-6,8-diene (15.43 %), β-pinene (10.59 %), elemol (8.31 %) and terpinene-4-ol (7.44 %). The essential oil showed strong antibacterial activity against S. aureus and E. coli, but no activity against P. aeruginosa and B. subtilis. Synergistic effects were observed because of the combined application of EO with gentamicin against all strains tested, and with amoxicillin against B. subtilis. Furthermore, the combination of EO/cefazolin demonstrated an additive effect against B. subtilis. In contrast, the combination of EO with amoxicillin and céfazoline revealed antagonistic effects against S. aureus, E. coli, and P. aeruginosa. Conclusion: This is the first report on the chemical composition and antibacterial activity of Algerian juniper berries’ essential oil. The results indicate that the studied EO may be a promising source of antibacterial compounds that could be useful for pharmaceutical applications especially in combination with conventional antibiotics.

Abstract. Benlembarek K, Lograda T, Ramdani M, Figueredo G, Chalard P. 2021. Chemical composition, antibacterial, antifungal and antioxidant activities of Taxus baccata essential oil from Algeria. Biodiversitas 22: 5475-5483. This work aims to study the chemical composition, the antibacterial, antifungal and antioxidant activities of Taxus baccata essential oil of Algeria. The essential oil was obtained by hydro distillation; its chemical composition was determined by GC and GC-MS analysis. The antibacterial and antifungal activities are evaluated by the disk diffusion method against three-gram negative bacteria, four-gram positive bacteria and four phytopathogenic fungi. The evaluation of antioxidant activity is carried out by the DPPH scavenging method. Twenty-seven compounds have been identified in the essential oil, where the major product was undecanone-2, followed by nonanone-2, tridecanone-2, decanone-2 and the methyl dehydroabietic. The T. baccata essential oil showed moderate antibacterial and antifungal activities against the strains tested, with the exception of E. faecalis, MRSA and Fusarium graminum, which have shown significant resistance. T. baccata essential oil has a moderate antioxidant activity.