The main objective of this research was to compare physicochemical parameters, antioxidant activity, lipid composition, and sensory analysis of initial and roasted carob pod powder (Ceratonia siliqua L.) obtained at different roasting temperatures. The roasted products became darker and the average moisture content, water activity, oil content, and sweetness values decreased at higher temperatures. Total polyphenol content and antioxidant activity increased with increasing roasted temperature. Oleic acid, linoleic acid, and palmitic acid were the main fatty acids present in carob oil. Results showed that the roasted carob pod powders are sweeter, have more caramel-like taste, and have more cacao-like aroma at lower roasting temperatures but have more astringent taste, coffee-like aroma, and roasted aroma at higher roasting temperatures.

Thymus fontanesii (thym) est une plante aromatique, répandue en Algérie et très utilisée par les populations locales pour ses vertus médicinales. L'huile essentielle de cette plante originaire de l'ouest algérien, fait l'objet dans cet article d'une étude physicochimique et microbiologique. L'extraction de l'huile essentielle a été effectuée par entraînement à la vapeur d'eau. Le rendement obtenu à partir des feuilles (2%) est intéressant pour l'exploitation industrielle. La densité spécifique (0.9219), l'indice de réfraction à 20° (1.4999), le pouvoir rotatoire (+3.4313), la miscibilité à l'éthanol (0.6V/1V), le point de congélation (<-20°), les indices d'acide (1.458), d'ester (16.83), d'iode (502.524) et de peroxyde (8000) ont été déterminé sur l'huile fraîchement extraite. Toutes ces valeurs sont comparables aux résultats obtenues pour les huiles essentielles de Thymus vulgaris et de Thymus Longiflorus , à l'exception du pouvoir rotatoire et de la miscibilité à l'éthanol. L'activité de l'huile essentielle de Thymus fontanesii sur les souches bactériennes (Escherichia coli ATCC 25922, Enterobacter cloaceae, Pseudomonas aeruginosa, Pseudomonas fluorescens, Acinetobacter baumannii, Bacillus cereus, Staphylococcus aureus ATCC 25923, Staphylococcus aureus S3)et fongiques (Penicilium spp, Aspergillus niger, Aspergillus flavus, Fusarium oxysporum, Rhizopus stolonifer, Candida albicans 444IPP), par la technique de Vincent (Aromatogramme) et la méthode de contact direct, montre que le pouvoir antimicrobien de cette huile est très important et se caractérise par une action bactéricide contre les bactéries gram négatif et bactériostatique contre les bactéries gram positif. Cette activité est plus importante sur les champignons que sur les bactéries. Le suivi de l'activité

In the present study, the chemical composition of the essential oil obtained from the aerial parts of Aaronsohnia pubescens (Desf.) K.Bremer & Humphries (Asteraceae), a chamomile-like medicinal plant, was studied. Using both GC-MS and GC-FID methods, 58 volatile compounds could be identified representing 96.6% of the total essential oil composition. The main compounds in the essential oil were monoterpene hydrocarbons such as (Z)-β-ocimene (53.8%), myrcene (15.2%) and α-pinene (7.7%). Moreover, the essential oil of A. pubescens was tested for its antifungal activity against seven strains of phytopathogenic fungi , i.e. Aspergillus niger, A. flavus, Penicillium purpurogenum, P. jensenii, P. expansum, and Fusarium oxysporum f.sp. albedinis, using the disc diffusion method. With the exception of P. jensenii, A. pubescens essential oil demonstrated a considerable antifungal activity against all tested strains. The present results confirm the traditional use of A. pubescens as a food preservative.

This work aims to study the chemical composition, antimicrobial and antioxidant activities of Juniperus phoenicea L. and Cotula cinerea (Del.) essential oils from southwestern Algeria. The hydrodistilled oils obtained were characterized by gas chromatography–mass spectrometry (GC– MS). A total of 45 and 25 compounds were identified representing 100% of Juniperus phoenicea L. and Cotula cinerea (Del.) respectively. The dominant component was α-pinene (46.437%) for Juniperus phoenicea L. and α-thujone (32.35%) for Cotula cinerea (Del.). The in vitro antibacterial activity of the essential oils was evaluated against nine foodborne pathogenic bacteria and one yeast, Candida albicans, using the disk diffusion method; the minimum inhibitory concentration (MIC) values were examined (micro dilution). The results suggest that the essential oil of Juniperus phoenicea has a significant to moderate antibacterial activity on all strains of bacteria. The most sensitive strains were Bacillus cereus, Bacillus subtilis, Micrococcus luteus, Pseudomonas aeruginosa, and Candida albicans with (MIC = 0.04 to 0.63 mg/ml). Cotula cinerea oil showed moderate to low sensitivity to the test strains. Its best activity was against Bacillus subtilis (MIC = 0.303 mg/ml). The DPPH test conducted to evaluate the antioxidant activity of both oils showed a good to moderate capacity for Juniperus phoenicea L. (concentration of an inhibitor when the response is reduced by half, IC50 = 0.76 mg/ml) and Cotula cinerea (Del.) [IC50 = 28. mg/ml] oils respectively. The promising bioactivities of these plants suggest that they may be a new source of preservative molecules.

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