Laboratory of Transmissible Diseases and Biologically Active Substances

Monastir, Tunisia

Laboratory of Transmissible Diseases and Biologically Active Substances

Monastir, Tunisia

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Sakka Rouis-Soussi L.,High Institute of Biotechnology of Monastir | El Ayeb-Zakhama A.,High Institute of Biotechnology of Monastir | Mahjoub A.,Laboratory of Transmissible Diseases and Biologically Active Substances | Ben Jannet H.,Reactivity | Harzallah-Skhiri F.,High Institute of Biotechnology of Monastir
EXCLI Journal | Year: 2014

The chemical composition of the essential oils of different Allium nigrum L. organs and the antibacterial activity were evaluated. The study is particularly interesting because hitherto there are no reports on the antibacterial screening of this species with specific chemical composition. Therefore, essential oils from different organs (flowers, stems, leaves and bulbs) obtained separately by hydrodistillation were analyzed using gas chromatography-mass spectrometry (GC-MS). The antibacterial activity was evaluated using the disc and microdilution assays. In total, 39 compounds, representing 90.8-96.9% of the total oil composition, were identified. The major component was hexadecanoic acid (synonym: palmitic acid) in all the A nigrum organs oils (39.1-77.2%). We also noted the presence of some sesquiterpenes, mainly germacrene D (12.8%) in leaves oil) and some aliphatic compounds such as n-octadecane (30.5%) in bulbs oil. Isopentyl isovalerate, 14-oxy-a-muurolene and germacrene D were identified for the first time in the genus Allium L. All the essential oils exhibited antimicrobial activity, especially against Enterococcus faecalis and Staphylococcus aureus. The oil obtained from the leaves exhibited an interesting antibacterial activity, with a Minimum Inhibitory Concentration (MIC) of 62.50 μg/mL against these two latter strains. The findings showed that the studied oils have antibacterial activity, and thus great potential for their application in food preservation and natural health products.


Ibrahim W.,Jean Monnet University | Ibrahim W.,Laboratory of Transmissible Diseases and Biologically Active Substances | Boukhadra N.,Jean Monnet University | Nasri-Zoghlami D.,Laboratory of Transmissible Diseases and Biologically Active Substances | And 5 more authors.
Clinical Microbiology and Infection | Year: 2014

Typing of human enterovirus (EV) remains a major goal for diagnostic and epidemiological purposes. Whereas sequencing of the VP1 coding region is the reference standard for EV typing, a method relying on sequencing of the VP2 coding region has been proposed as an alternative; however, this has been validated only on cell culture supernatants. To avoid the selection of cultivable strains and to quicken the identification step, a new semi-nested PCR method targeting the VP2 region was developed by use of the CODEHOP strategy. After validation of the method on reference and clinical strains, a total of 352 clinical specimens found to be positive for EV RNA (138 with the GeneXpert EV kit and 214 with the Enterovirus R-gene kit) during a 3-year period (2010-2012) were analysed prospectively for VP2 genotyping. Overall, 204 (58%) specimens were typeable. A higher proportion of throat swab/stool specimens than of cerebrospinal fluid (CSF) specimens was found to be typeable (94 of 142 (66.2%) vs. 83 of 169 (49.1%), respectively, p <0.01 by the chi-square test). Moreover, the median Ct value obtained was lower for typeable specimens than for untypeable specimens (32.20 vs. 33.01, p <0.05, and 25.96 vs. 31.74, p <0.001, for the GeneXpert and R-gene tests, respectively, by the Mann-Whitney-Wilcoxon test). These results suggest that, in cases of EV meningitis, a peripheral specimen (i.e. throat swab or stool) that is susceptible to exhibiting a higher viral load should be used in preference to CSF for identifying the causative EV genotype by use of the VP2 typing method without cell culture isolation. © 2013 The Authors.


Ibrahim W.,Laboratory of Transmissible Diseases and Biologically Active Substances | Ibrahim W.,Jean Monnet University | Ouerdani I.,Laboratory of Transmissible Diseases and Biologically Active Substances | Pillet S.,Jean Monnet University | And 3 more authors.
Journal of Virological Methods | Year: 2014

A RT-PCR approach for the direct detection and typing of human enteroviruses in the environment is described in this study. A semi-nested RT-PCR using COnsensus-DEgenerated Hybrid Oligonucleotide Primers (CODEHOP) designed from the VP2 genome region has been developed for the direct typing of enteroviruses in clinical samples (Ibrahim et al., 2013). This CODEHOP/VP2 PCR strategy as well as the CODEHOP/VP1 technique described by Nix et al. (2006), were tested for the detection and typing of enteroviruses in wastewater samples. Virus particles were first extracted and concentrated from wastewater samples by using respectively beef extract and polyethylene glycol 6000, and the presence of enteroviruses was screened by a RT-PCR method using primers from the 5'-end non-coding region (5'NCR). Fifty-two of 172 samples (30.2%) were revealed positive by the 5'NCR method. From these 52 samples, only 19 samples (36.5%) were found positive by at least one of the two CODEHOP techniques, with the following distribution: VP1(+)/VP2(+) = 4 (7.7%), VP1(-)/VP2(+) = 13 (25%) and VP1(+)/VP2(-) = 2 (3.8%). These results illustrate that the direct typing of enteroviruses in environmental samples is insensitive, possibly due to the presence of large amounts of amplification inhibitors; however, the VP2 method was found able to allow the direct detection and typing of c. one-third of the positive environmental samples. © 2014 Elsevier B.V.


Marzouki H.,Laboratory of Transmissible Diseases and Biologically Active Substances | Marzouki H.,University of Cagliari | Falconieri D.,University of Cagliari | Falconieri D.,Instituto Tecnico Giua Cagliari | And 3 more authors.
Asian Journal of Chemistry | Year: 2015

The chemical composition of the essential oil obtained from the needles of Pinus pinaster by hydrodistillation was analyzed by gas chromatography-mass spectrometry. Fifty components were detected, of which 41 were identified for a total percentage of about 98 %. The main components of the essential oil of needles from Tunisia were abietadiene (25.4 %), 13-epi-manoyl oxide (16.6 %), abietatriene (10.2 %), β-caryophyllene (11.1 %), 13(16), 14-labdien-8-ol (5.9 %) and α-pinene (5.3 %) whereas the oil from Italy was predominantly composed of limonene (36.7 %), abienol (13.4 %), manoyl oxide (6.5 %) and β-caryophyllene (5.8 %).


Marzouki H.,Laboratory of Transmissible Diseases and Biologically Active Substances | Mighri H.,Arid Land Institute | Salah K.B.,Laboratory of Transmissible Diseases and Biologically Active Substances | Falconieri D.,Instituto Tecnico Industriale Statale Michele Giua | Piras A.,University of Cagliari
Asian Journal of Chemistry | Year: 2015

This study shows the variations between ten Laurus nobilis L. trees from different Tunisian localities in relation to the morphological parameters, composition of essential oils extracted from leaves and their antibacterial activity. Aggregation of trees according to their geographical origin seems not evident. Two main groups of populations were clearly separated according principally, to the leaves size and the inflorescences number. The leaves essential oil composition did not vary throughout the Laurus nobilis L. trees and all analyzed samples were dominated by oxygenated monoterpenes 1,8-cineole, methyl eugenol and α-terpinyl acetate. Specially, oils rich in 1,8-cineole were demonstrated to have potent activities against the S. aureus and E. faecalis. Individual plant evaluation, however, remains the only way to effectively seek for well defined essential oil composition or specific combinations of morphological and analytical characters.


Abdelkader H.B.,University of Monastir | Salah K.B.H.,Laboratory of Transmissible Diseases and Biologically Active Substances | Liouane K.,University of Monastir | Boussaada O.,Laboratory of Conservation and Valorisation of Plant Resources | And 5 more authors.
African Journal of Microbiology Research | Year: 2010

This study examined the in vitro antibacterial and antifungal activities of the extracts (butanolic, ethyl acetate, petroleum ether and the product H2) of 2 plants belonging to the Asteraceae family: Rhaponticum acaule L. and Scorzonera undulata L. Butanolic and ethyl acetate extracts of the Rhaponticum acaule plant showed a moderate antibacterial activity against 3 of the tested strains; Staphylococcus aureus, Escherichia coli and Enterococcus fecalis while Proteus mirabilis, Pseudomonas aeruginosa and Citrobacter freundeï were resistant to the extracts. The product H2 showed an antibacterial activity against S. aureus, C. freundeï and E. fecalis. From the results of the antifungal activity, we observed that butanolic and ethyl acetate extracts of R. acaule showed a strong inhibition against Trichophyton rubrum with inhibition percentage of 56.25 and 78.75%, respectively. Butanolic extract showed a moderate inhibition of Microsporum canis, Scopulariopsis brevicaulis and Aspergillus fumigatus while ethyl acetate extract showed low inhibition. The aerial part ethyl acetate extract of S. undulata seemed to be more active than the petroleum one. It showed an antibacterial activity against all bacteria strains tested except for E. coli. For antifungal activity, the petroleum ether and ethyl acetate extracts of the aerial part inhibited strongly all tested fungi. The roots extracts from S.undulata show weak antimicrobial activities compared with the aerial parts extracts of the same plant. © 2010 Academic Journals.


Fdhila K.,University of Monastir | Haddaji N.,University of Monastir | Chakroun I.,University of Monastir | Macherki M.E.E.,University of Monastir | And 2 more authors.
Fish and Shellfish Immunology | Year: 2016

We examine the effect of Glucomannan, extracted from Candida utilis yeast, on immune parameters and resistance to Vibrio splendidus of Crassostreagigas. Our results showed that Glucomannan was a successful anti-adhesive molecule; it exhibited a stronger inhibitory effect on adhesion of Vibrio splendidus in infected Crassostreagigas. Vibrio splendidus viable cells number declined after incubation with Glucomannan. Furthermore, the Glucomannan diet showed higher activity to trigger the immune response against bacteria. Glucomannan applications, in biological control of seafood associated pathogens can be an alternative solution, providing consumer with a product of good quality owing to the use of 40 non-toxic compounds. Based on our results, Glucomannan could be used as a bio-protective culture in oyster's depuration to prevent Vibrio splendidus growth. © 2016 Elsevier Ltd


PubMed | Laboratory of Transmissible Diseases and Biologically Active Substances and University of Monastir
Type: | Journal: Fish & shellfish immunology | Year: 2016

We examine the effect of Glucomannan, extracted from Candida utilis yeast, on immune parameters and resistance to Vibrio splendidus of Crassostreagigas. Our results showed that Glucomannan was a successful anti-adhesive molecule; it exhibited a stronger inhibitory effect on adhesion of Vibrio splendidus in infected Crassostreagigas. Vibrio splendidus viable cells number declined after incubation with Glucomannan. Furthermore, the Glucomannan diet showed higher activity to trigger the immune response against bacteria. Glucomannan applications, in biological control of seafood associated pathogens can be an alternative solution, providing consumer with a product of good quality owing to the use of 40 non-toxic compounds. Based on our results, Glucomannan could be used as a bio-protective culture in oysters depuration to prevent Vibrio splendidus growth.

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