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Berka-Zougali B.,University of La Rochelle | Berka-Zougali B.,Laboratory of Research on Bio active Products and Valorization of Biomasse | Berka-Zougali B.,University of Science and Technology Houari Boumediene | Hassani A.,Laboratory of Research on Bio active Products and Valorization of Biomasse | And 3 more authors.
Journal of Chromatography A | Year: 2010

In the present work, the new extraction process of Détente Instantanée Contrôlée DIC (French, for instant controlled pressure drop) was studied, developed, quantitatively and qualitatively compared to the conventional hydrodistillation method for the extraction of essential oils from Algerian myrtle leaves. DIC was used as a thermomechanical treatment, DIC subjecting the product to a high-pressure saturated steam. The DIC cycle ends with an abrupt pressure drop towards vacuum, and this instantly leads to an autovaporization of myrtle volatile compounds. An immediate condensation in the vacuum tank produced a micro-emulsion of water and essential oils. Thus, an ultra-rapid cooling of residual leaves occurred, precluding any thermal degradation. An experimental protocol was designed with 3 independent variables: saturated steam pressure between 0.1 and 0.6. MPa, resulting in a temperature between 100 and 160 °C, a total thermal processing time between 19 and 221. s, and between 2 and 6 DIC cycles. The essential oils yield was defined as the main dependent variable. This direct extraction gave high yields and high quality essential oil, as revealed by composition and antioxidant activity (results not shown). After this treatment, the myrtle leaves were recovered and hydrodistilled in order to quantify the essential oil content in residual DIC-treated samples. Scanning electron microscope (SEM) showed some modification of the structure with a slight destruction of cell walls after DIC treatment. © 2010 Elsevier B.V.


Berka-Zougali B.,University of La Rochelle | Berka-Zougali B.,Laboratory of Research on Bio active Products and Valorization of Biomasse | Ferhat M.-A.,Laboratory of Research on Bio active Products and Valorization of Biomasse | Hassani A.,Laboratory of Research on Bio active Products and Valorization of Biomasse | And 2 more authors.
International Journal of Molecular Sciences | Year: 2012

Two different extraction methods were used for a comparative study of Algerian Myrtle leaf essential oils: solvent-free-microwave-extraction (SFME) and conventional hydro distillation (HD). Essential oils analyzed by GC and GC-MS presented 51 components constituting 97.71 and 97.39% of the total oils, respectively. Solvent-Free-Microwave-Extract Essential oils SFME-EO were richer in oxygenated compounds. Their major compounds were 1,8-cineole, followed by α-pinene as against α-pinene, followed by 1,8-cineole for HD. Their antimicrobial activity was investigated on 12 microorganisms. The antioxidant activities were studied with the 2,2-diphenyl-1-picrylhydrazyl (DPPH•) radical scavenging method. Generally, both essential oils showed high antimicrobial and weak antioxidant activities. Microstructure analyses were also undertaken on the solid residue of myrtle leaves by Scanning Electronic Microscopy (SEM); it showed that the SFME-cellular structure undergoes significant modifications compared to the conventional HD residual solid. Comparison between hydro distillation and SFME presented numerous distinctions. Several advantages with SFME were observed: faster kinetics and higher efficiency with similar yields: 0.32% dry basis, in 30 min as against 180 min for HD. © 2012 by the authors.


Mohammedi H.,University of Science and Technology Houari Boumediene | Mecherara-Idjeri S.,University of Science and Technology Houari Boumediene | Foudil-Cherif Y.,University of Science and Technology Houari Boumediene | Hassani A.,Laboratory of Research on Bio active Products and Valorization of Biomasse
Journal of Essential Oil-Bearing Plants | Year: 2015

Abstract: The essential oil content and their chemical composition of aerial part, flowers, and both leaves and stems of wild carrot growing in Algeria (Daucuscarota L. ssp. Carota) as well as aerial part at different plant maturity stages was examined. The qualitative and quantitative analyses of the essential oils were performed using GC, GC-MS and 13C-NMR. 57 compounds were identified representing more than 85% of the total oil in each sample. Generally, The main components in the essential oil of aerial part in full flowering were α-pinene (21.3 %) and asarone (18.4 %), while the essential oils isolated from flowers and both leaves and stems were dominated by asarone (9.8, 9.4 %), α-pinene(10.9, 10.6 %) and β-bisabolene (7.6, 9.3 %) respectively. Before flowering and after flowering the major constituents were the linalool (11.2 %) and asarone (20.8 %) respectively. The antioxidant potential of the different essential oils was evaluated using the inhibition of free radical 2,2-diphenyl-1-picrylhydrazyl (DPPH) method. All essential oils showed a relatively weak antioxidant capacity. The results obtained from the essential oils of the aerial part in full flowering 50 showed the strongest activity against DPPH than the other samples (IC =96,4±1.1 µg/ml). © 2015 Har Krishan Bhalla & Sons.

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