Vol 02, NO 2 (juillet 2018) numéro complet PDF (4.47 MB) 45p
Sommaire Vol 02, NO 2 (juillet 2018) PDF (70,08 KB) 1p
1. Growth inhibition of Staphylococcus aureus, Bacillus cereus, and Escherichia coli assessed in vitro and in food system using thyme and mentha essential oils. PDF (235,52KB) pp 1-10
Tahar Amrouche1*, Djamel Djenane1, Faiza. Dziri1, Kaissa Danoun1, Mouloud Djerbal1 and Pedro Roncalés Rabinal2
1Laboratory of quality and food safety, Faculty of Biological sciences and Agronomy, M. Mammeri University, Tizi Ouzou, Algeria
2Facultad de Veterinaria de la Universidad de Zaragoza, Zaragoza (Spain)
* Correspondence To: Tahar Amrouche : This email address is being protected from spambots. You need JavaScript enabled to view it.
Abstract
This study aimed to assess the antibacterial activity of essential oils (EOs) from Thymus vulgaris, Thymus satureoides, Mentha piperita, and Mentha spicata in vitro and in beef minced meat. The inhibitory effect of EOs on Staphylococcus aureus, Bacillus cereus, and Escherichia coli was evaluated by agar diffusion method and dilution assay. The EOs were tested in in food system calculating CFU in stored (refrigerated) minced beef meat inoculated with pathogens. Results showed the inhibitory effect of thyme and mentha EOs on all bacteria tested in Muller Hinton media. Indeed, S. aureus and B. cereus were more sensitive to T. vulgaris EOs. The addition of EOs to inoculated minced beef resulted in decrease of S. aureus, B. cereus and E. coli population after 4 days of storage. These findings suggested the possibility of using of thyme and mentha EOs as natural preservatives in meat and meat products preservation.
Key words: Antimicrobials, essential oils, meat, mentha, thyme
2. Les probiotiques et leur métabolites : une alternative de traitement des pathologies gastro-intestinales. PDF(751,36KB) pp 11-22
Guetarni Hassina
Département des sciences biologiques, Faculté des sciences de la nature et de la vie et des sciences de la terre, Université Djilali Bounaama, Khemis Miliana, 44225, Ain Defla, Algérie.
Correspondance avec: Guetarni Hassina: This email address is being protected from spambots. You need JavaScript enabled to view it.
Résumé
Les probiotiques produisent de nombreux métabolites aux propriétés antimicrobiennes. L’objectif de ce travail est d’analyser des métabolites sécrétés par des bactéries lactiques responsables de l’inhibition des bactéries pathogènes impliquées dans les infections gastro-intestinales.
Des concentrations d’acide lactique varient de 0,075 g/l et de 0,077 g/l ont été enregistrées par HPLC. L’acide lactique est responsable de l’inhibition des souches d’Escherichia coli et Salmonella typhi. Une bactériocine stable à pH acide et basique et thermorésistante a montré un net effet inhibiteur des souches de référence, cliniques et souches d’Helicobacter pylori caractérisées par PCR en temps réel.
Mots clés : Probiotiques, métabolites, bactéries pathogènes, PCR, HPLC.
Abstract
Probiotics produce many metabolites with antimicrobial properties. The aim of this work is to analyze metabolites secreted by lactic acid bacteria responsible for the inhibition of pathogenic bacteria involved in gastrointestinal infections.
Lactic acid concentrations of 0.075 g / l and 0.077 g / l were recorded by HPLC. Lactic acid is responsible for the inhibition of Escherichia coli and Salmonella typhi. A bacteriocin stable at acidic and basic pH and heat resistant showed a clear inhibitory effect of reference, clinical and strains of Helicobacter pylori characterized by real time PCR.
Key words: Probiotics, metabolites, pathogenic bacteria, PCR, HPLC.
3. Purification et d’une molécule bactéricide issue du venin de serpent Cerastes cerastes. PDF (351,59KB) pp 23-33
Ziad-Meziane Hanane-Fadila* and Laraba-Djebari Fatima
USTHB, Laboratoire de Biologie Cellulaire et Moléculaire. Faculté des Sciences Biologiques, BP 32, El-Alia, Bab Ezzouar, 16111 Alger, Algérie.
*Correspondance avec : Ziad-Meziane Hanane-Fadila : This email address is being protected from spambots. You need JavaScript enabled to view it.
Abstract
New antibacterial molecules from natural secretions could be beneficial in the development of new drugs against antibiotic bacteria resistance. In this study, Cerastes cerastes venom was investigated for its antibacterial activity against Gram-positive and Gram-negative bacteria. The antibacterial activity was evaluated by measuring the inhibition aera and minimum inhibitory concentration (MIC). three chromatographic stepswere used to extract an L-amino acid oxidase (CcLAAO) from this venom using. CcLAAO presents an antibacterial activity against three bacterial strains (Staphylococcus aureus,Methicillin-resistant S. aureus, and Pseudomonas aeruginosa) with MIC values of 10, 10, and 20 μg/mL, respectively. CcLAAO presents a bactericidal effect toward Staphylococcus aureus with a minimum bactericidal concentration of 40 μg/mL. However, no effect was observed against Escherichia coli and yeast strains.
Résumé
De nouvelles molécules antibactériennes de sécrétions naturelles pourraient être utiles dans le développement de nouveaux médicaments à l’encontre de la résistance des bactéries aux antibiotiques. Dans cette étude, le venin du serpent Cerastes cerastes a été étudié pour son activité antibactérienne contre les bactéries Gram-positives et Gram-négatives. L'activité antibactérienne a été évaluée par mesure de l’halo d'inhibition et de la concentration minimale inhibitrice (CMI). Une nouvelle L-amino acide oxydase (CcLAAO) a été purifiée à partir de ce venin utilisant trois étapes chromatographiques. La CcLAAO est dotée d’une activité antibactérienne vis-à-vis de trois souches bactériennes (Staphylococcus aureus, Staphylococcus aureus résistante à la méthicilline et Pseudomonas aeruginosa) avec des valeurs de CMI de 10, 10, et 20 ug/mL, respectivement. CcLAAO presente un effet bactéricide avec une Concentration minimale Bactéricide 40 ug/mL vis-à-vis du Staphylococcus aureus. Cependant, aucun effet n’était observé contre Escherichia coli et la levure Candida albicans.
Mot Clés : Viperidae, Cerastes cerastes, L-amino acide oxidase, activité Antibactérienne.
4. Antimicrobial evaluation of new substituted hantzsch thiazole derivatives. PDF (392,93KB) pp 34-38
Houria Bouherrou1*, Yahia Rachedi1, Ahmed Abderrahmani2, Lamia Abdellaziz2 and Françoise Dumas3
1Laboratory of Applied Organic Chemistry, Faculty of Chemistry, University of Science and Technology Houari Boumediene, BP 32, El-Alia, 16111 Bab-Ezzouar, Algiers, Algeria.
2Laboratory of Cellular and Molecular Biology, Faculty of Biological Sciences, USTHB, BP 32, El Alia, 16111, Bab Ezzouar, Algiers, Algeria.
3 Laboratoire BioCIS, UMR CNRS8076, Chimie des Substances Naturelles, IPSIT and LabEx LERMIT,CNRS, Université Paris-Saclay, Université Paris-Sud, Faculté de Pharmacie, 5, rue Jean-Baptiste Clément, 92296 Châtenay-Malabry CEDEX, France.
* Corespendence to : Houria Bouherrou: This email address is being protected from spambots. You need JavaScript enabled to view it.
Abstract
New thiazole derivatives were synthesized and tested as antimicrobial agents. Synthesized compounds were assayed in vitro for their antimicrobial activity against a panel of selected Gram positive and Gram negative bacteria such as Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa by the disc diffusion and the serial dilution methods. Most of the thiazoles exhibited significant antibacterial activity compared to amoxicillin and ciprofloxacin as positive controls. The entire synthesized compounds and standard antibiotics have effective antibacterial properties against bacteria strains and are most active against Gram negative bacteria than the Gram positive one.
Keywords: Thiazoles; Antibacterial activity; Gram positive bacteria; Gram negative bacteria.
5. Inhibition du biofilm formé par Klebsiella pneumoniae responsable d’infection urinaire par l’huile essentielle et les polyphenols de Lavandula officinalis. PDF (236,68KB) pp 39-45
Afif Chaouche Thinina1*, Arab Karim1, Laoufi Razika2, Malek Malya3
1 Laboratoire de Valorisation et de Conservation des Ressources Biologiques. UMBB, Algérie.
2 Laboratoire de Technologies, Valorisation, Physicochimie du matériel biologique et biodiversité, UMBB, Algérie.
3 Aix-Marseille Université, AMU, faculté de médecine, Marseille, France.
* Correspondance avec : This email address is being protected from spambots. You need JavaScript enabled to view it.
Résumé
L’échec de l’antibiothérapie n’est pas rare dans les infections urinaires à Klebsiella pneumoniae, la formation de biofilm peut compromettre la réussite de l’antibiothérapie. Cette étude propose des molécules bioactives comme alternative.
L’huile essentielle et les polyphénols de Lavandula officinalis ont été extraits. Des souches bactériennes de Klebsiella pneumoniae ont été isolées à partir d’infections urinaires. La capacité de ces souches à former des biofilms est testée. Après, l’activité antimicrobienne et l’évaluation du pouvoir inhibiteur de formation de biofilms des extraits ont été testées.
Certaines souches isolées peuvent former des biofilms, les huiles essentielles inhibent la formation de biofilms à une concentration de 1/4, les polyphénols sont actifs à partir de 7.5 mg/ml.
Mots clés : Lavandula officinalis, Klebsiella pneumoniae, huiles essentielles, polyphénols, biofilms.
Abstract
Failure of chemotherapy is not uncommon in urinary tract infections with Klebsiella pneumoniae biofilm synthesis can cause this compromise this medical procedure. This study proposes bioactive molecules as alternatives.
Essential oils and polyphenols from Lavandula officinalis were extracted. Bacterial strains of Klebsiella pneumoniae were isolated from urinary tract infections. Their ability to form biofilm was assessed. After, we used antimicrobial acidity to assess its ability to prevent biofilms genesis.
Isolated strains were able to synthesize biofilms, essential oils showed a clear activity from 1/4 And polyphenols show it from 7.5 mg/ml.
Key words: Lavandula officinalis, biofilm, essential oils, polyphenols, biofilms.