Chemical composition and antimicrobial and antioxidant activities of Tunisian, France and Austrian Laurus nobilis (Lauraceae) essential oils

Abstract

Essential oil (EO) of Laurus nobilis, from Tunisian, France and Austrian were screened for their chemical composition, antioxidant and antimicrobial activities and compared. GC-MS analysis showed that leaves of Tunisian L. nobilis had camphor (34.43%), 1,8-cineole (20.21%) and α-terpineol (7%) as major components. France and Austrian EOs had a high content of 1,8-cineole (45.8% and 43.4%, respectively) followed by bornyl acetate (13.8% and 17.7% respectively) and methyl eugenol (7.7% and 10.9% respectively). Antioxidant potential was measured by ABTS and DPPH tests. Tunisian L. nobilis EO showed greater radical scavenging by ABTS activity (IC50=44.8±0.1 mg/L) than the France and Austrian EOs (76.4±3.2 mg/L and 81.4±4.0 mg/L, respectively). However, for DPPH test system, French and Austrian EOs activities were excellent (IC50=176.1±5.1 mg/L and 236.3±2.9 mg/L respectively) then Tunisian L. nobilis EO (IC50=2859.7±99.0 mg/L). A good Antimicrobial activity was observed on the yeasts and fungi for all EOs. Tunisian laurel EO show a better antibacterial activity against gram-negative bacteria (Klebsiella pneumonial, E. coli and Salmonella enterica CMI: 0.004 mg/ml) than gram-positive ones (Bacilus subtilis, Staphylococcus aureus and Listeria monocytogenes CMI: 0.01 mg/ml). A significant antifungal activity of Tunisian EO was also observed against fungi and yeasts species (CMI: 0.004 mg/ml). France essential oil shows better activities against all organisms tested wail Austrian oil activity is more important against yeasts species tested and Mucor ramannianus (fungi). Chemical composition, antimicrobial and antioxidant activity of Tunisian L. nobilis essential oil, were different from that of France and Austrian and it give the opportunity for its uses in new pharmaceuticals and natural therapies of infectious diseases.

New coating containing chitosan and Hyssopus officinalis essential oil (emulsion and nanoemulsion) to protect shrimp (Litopenaeus vannamei) against chemical, microbial and sensory changes

“…HEO 0.5 and 1 % had a good effect on pH value compared to the control group, although it had a lower effect than CE + HEO and NE + HEO. The highest pH value was assessed in the control sample (8.19 ± 0.01) that the increase in the pH in samples might be associated with the production of alkaline substances (such as ammonia, trimethylamine, indole, and histamine), autolysis process, endogenous enzymes (lipases and proteases) or microbial enzymes activity that leads to an increase in volatile bases during long-term storage ( Homayounpour et al, 2021 , Kizil et al, 2010 , Noori et al, 2018 , Shahbazi, 2017 ). It is also thought that the increase in pH during storage at cold temperatures is due to the production of amines by amino acid decarboxylation ( Aşik and Candoğan, 2014 , Homayounpour et al, 2021 , Kizil et al, 2010 , Noori et al, 2018 , Shahbazi, 2017 ).…”

“…The highest pH value was assessed in the control sample (8.19 ± 0.01) that the increase in the pH in samples might be associated with the production of alkaline substances (such as ammonia, trimethylamine, indole, and histamine), autolysis process, endogenous enzymes (lipases and proteases) or microbial enzymes activity that leads to an increase in volatile bases during long-term storage ( Homayounpour et al, 2021 , Kizil et al, 2010 , Noori et al, 2018 , Shahbazi, 2017 ). It is also thought that the increase in pH during storage at cold temperatures is due to the production of amines by amino acid decarboxylation ( Aşik and Candoğan, 2014 , Homayounpour et al, 2021 , Kizil et al, 2010 , Noori et al, 2018 , Shahbazi, 2017 ). Also, the relationship between the pH index and the number of psychrophilic and mesophilic microorganisms evaluated by the Pearson test confirms the significant relationship between the increase in the number of microorganisms and the increase in pH ( Aşik and Candoğan, 2014 , Homayounpour et al, 2021 , Hussain et al, 2021 , Kizil et al, 2010 , Razavi et al, 2020 ).…”

“…It is also thought that the increase in pH during storage at cold temperatures is due to the production of amines by amino acid decarboxylation ( Aşik and Candoğan, 2014 , Homayounpour et al, 2021 , Kizil et al, 2010 , Noori et al, 2018 , Shahbazi, 2017 ). Also, the relationship between the pH index and the number of psychrophilic and mesophilic microorganisms evaluated by the Pearson test confirms the significant relationship between the increase in the number of microorganisms and the increase in pH ( Aşik and Candoğan, 2014 , Homayounpour et al, 2021 , Hussain et al, 2021 , Kizil et al, 2010 , Razavi et al, 2020 ). This study was similar to the Homayonpor et al study.…”

“…The device was equipped with a DB-5 column (length 30 m, inner diameter 0.25 mm, inner layer thickness 0.25 µm), helium carrier gas with a flow of 1.1 mL/min, column temperature program was from 60 to 250 °C with the speed of 5 °C/min. The isolated compounds were identified following the mass spectrometer library (Saturn version 4; Agilent Technology Inc., Santa Clara, USA), the decomposition patterns presented in the other studies, and the calculation of the Quats index ( Kizil et al, 2010 , Soleymani and Pirzad, 2015 ). The relative amounts of components were determined according to the percentage of surface area under the peak ( Fraternale et al, 2004 , Homayounpour et al, 2021 ).…”

“…The Hyssop ( Hyssopus officinalis ) has a sharp and biting taste with a delightful smell that resembles the smell of mint. Hyssop essential oil has antibacterial and antioxidant properties due to its phenolic compounds ( Fraternale et al, 2004 , Kizil et al, 2010 ).…”