Browsing by Author "Lenchi, Nesrine"

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Chemical composition, antimicrobial and antioxidant activities of methanolic extracts of the Algerian Artemisia campestris L. at different stage of growth
(Springer, 2024) Brahmi, Fairouz; Berrached, Rachda; Kebbouche Gana, Salima; Kadik, Leila; Lenchi, Nesrine
Artemisia campestris, widely abundant in North Africa, is usually used as a decoction to treat several diseases; but its chemical composition at different growth stages and along a climatic gradient has never been investigated. In this study, phytochemical content, antioxidant and antimicrobial activities of crude methanolic fractions from dry aerial parts of A. campestris, growing in two different bioclimatic conditions, were compared. The growth stages, vegetative and reproductive, were also taken into consideration. The HPLC analysis revealed the presence of several compounds like ascorbic, isovannilic, ferrulic and cinnapic acids. The antioxidant activity was evaluated with two different methods: DPPH and FRAP essay. The four samples showed very high antioxidant activity. The in vitro antimicrobial activity shows a strong inhibitory effect against gram positive bacteria. But, they were resistant to gram negative bacteria and yeast. The biggest inhibition diameter was recorded against S. aureus and B. cereus.
Chemical composition, antimicrobial and insecticidal activities of Olea europaea L. ssp. sativa. collected from East of Algeria
(Springer, 2025) Brahmi, Fairouz; Benlefki, Nawal; Koullal, Radwa; Kebbouche-Gana, Salima; Lenchi, Nesrine
Olea europaea L., commonly known as the olive tree, is extensively utilized in Algeria for its medicinal properties. This plant is rich in alkaloids, phenolic acids, and flavonoids. The aim of this study was to evaluate the antimicrobial and insecticidal activities of methanol extracts and oils harvested from the aerial parts of Olea europaea L. ssp. sativa from two different regions (Bouira and Bordj Bouarreridj). Adult aphids (Aphis fabae) treated with crude methanol extracts exhibited high mortality rates, reaching up to 100%, while diluted extracts caused mortality rates between 80 and 100%. In terms of antimicrobial activity, all tested strains exhibited resistance (including E. coli, B. subtilis, S. aureus, K. pneumoniae, S. agalactiae, and C. albicans) for all methanol extracts and both oils. However, significant inhibition percentages were noted against the fungus Cladosporium sp. across the various tested extracts. These extracts have the potential to be used in the food, pharmaceutical and agricultural industries
Comparison of microbial community composition in injection and formation water from Algerian oilfields
(2012) Lenchi, Nesrine; Inceoğlu, Özgül; Kebbouche-Gana, Salima; Gana, Mohamed Lamine; Llirós, Marc; Servais, Pierre; Garcia-Armisen, Tamara
Diesel Biodegradation Capacities and Biosurfactant Production in Saline-Alkaline Conditions by Delftia sp NL1, Isolated from an Algerian Oilfield
(Taylor and Francis Inc., 2020) Lenchi, Nesrine; Kebbouche-Gana, Salima; Servais, Pierre; Gana, Mohamed Lamine; Llirós, Marc
In this study, a diesel oil-degrading bacterium was isolated from an oilfield water injection (water-bearing formations, 1,205 m depth) in Algeria. The bacterial strain, designated NL1, was cultivated on diesel oil as sole carbon and energy sources. Molecular analyses of the 16S rRNA gene sequence (KY397882) placed NL1 strain closely related to distinct cultivated species of the Delftia genus. Optimal diesel oil biodegradation by Delftia sp NL1 strain occurred at pH 11, 40 °C, 2 M NaCl and initial hydrocarbon concentration of 5% (v/v) as sole carbon source. GC-MS analyses evidenced that strain Delftia sp NL1 was able to degrade more than 66.76% of diesel oil within only 7 days. On the other hand, and in the same conditions, biosurfactant production by Delftia sp NL1 was also evaluated evidencing high emulsifying capacity (E24 = 81%), ability to lower the surface tension of growing media (with the value of 25.7 mN m− 1), and production of glycolipids (8.7 g L−1) as biosurfactants. This research presents indigenous strain Delftia sp NL1 for diesel degradation and synthesis of biosurfactant in extreme conditions. In this sense, strain NL1 is a good candidate for possible in situ oil recovery and in wastewater treatment in refineries and oil terminals in petroleum industry
Diversity of microbial communities in production and injection waters of algerian oilfields revealed by 16S rRNA gene amplicon 454 pyrosequencing
(2013) Lenchi, Nesrine; Kebbouche-Gana, Salima; Gana, M.A.; Lliro, M.; Servais, P.
The microorganisms inhabiting many petroleum reservoirs are multi-extremophiles capable of surviving in environments with high temperature, pressure and salinity. Their activity influences oil quality and they are an important reservoir of enzymes of industrial interest. To study these microbial assemblages and to assess any modifications that may be caused by industrial practices, the bacterial and archaeal communities in waters from four Algerian oilfields were described and compared. Three different types of samples were analyzed: production waters from flooded wells, production waters from non-flooded wells and injection waters used for flooding (water - bearing formations). Microbial communities of production and injection waters appeared to be significantly different. From a quantitative point of view, injection waters harbored roughly ten times more microbial cells than production waters. Bacteria dominated in injection waters, while Archaea dominated in production waters. Statistical analysis based on the relative abundance and bacterial community composition (BCC) revealed significant differences between production and injection waters at both OTUs 0.03 and phylum level. However, no significant difference was found between production waters from flooded and non-flooded wells, suggesting that most of the microorganisms introduced by the injection waters were unable to survive in the production waters. Furthermore, a Venn diagram generated to compare the BCC of production and injection waters of one flooded well revealed only 4% of shared bacterial OTUs. Phylogenetic analysis of bacterial sequences indicated that Alpha- , Beta- and Gammaproteobacteria were the main classes in most of the water samples. Archaeal sequences were only obtained from production wells and each well had a unique archaeal community composition, mainly belonging to Methanobacteria , Methanomicrobia , Thermoprotei and Halobacteria classes. Many of the bacterial genera retrieved had already been reported as degraders of complex organic molecules and pollutants. Nevertheless, a large number of unclassified bacterial and archaeal sequences were found in the analyzed samples, indicating that subsurface waters in oilfields could harbor new and still-non-described microbial species
Draft Whole-Genome sequences of microbacterium oxydans and microbacterium maritypicum strains
(American Society for Microbiology, 2023) Lenchi, Nesrine
Microbacterium spp. are a group of microbes that have been recovered from a wide variety of environments in nature. Here, I report the complete genomic data for Microbacterium oxydans and Microbacterium maritypicum type strains that are already present in public culture repositories. The genome of the M. oxydans strain was 3,894,869 bp long, with a G1C content of 68.26%. The genome of the M. maritypicum strain was 3,668,377 bp long, with a G1C content of 68.44%
Etude de la biodiversité microbienne dans les écosystèmes aquatiques pétroliers
(2014) Lenchi, Nesrine
Les micro-organismes habitant de nombreux gisements pétroliers sont des multiextrêmophiles capables de survivre dans des environnements ou règne de hautes températures, pressions et salinités. Leurs activités influencent la qualité du pétrole et sont aussi un important réservoir d’enzymes d'intérêts industriels. Afin d’étudier la composition de cette communauté microbienne et évaluer les modifications qui pourraient être causées par les pratiques industrielles, les communautés bactériennes et archéennes présentent dans les eaux de quatre champs pétrolifères algériens ont été décrites et comparées. Trois différents types d'échantillons ont été analysés : les eaux de production de puits touchés par les eaux d’injection, les eaux de production non touchées par les eaux d’injection et des eaux d’injection. Les communautés microbiennes des eaux de production semblent être sensiblement différentes de celles des eaux d'injection. D'un point de vue quantitatif, les eaux d'injection abritaient environ dix fois plus de cellules microbiennes que les eaux de production. Les bactéries dominent dans les eaux d’injection, tandis que les archées dominent dans les eaux de production. L'analyse statistique basée sur l'abondance relative et la composition de la communauté bactérienne (CCB) a révélé des différences significatives entre les eaux de production et les eaux d’injection aussi bien au niveau OTUs0.03 qu’au niveau phylum. Toutefois, aucune différence significative n'a été retrouvée entre les eaux de production touchées ou non touchées par les eaux d’injection, ce qui suggère que la plupart des micro-organismes introduits par l'eau d'injection ont été incapables de survivre dans les eaux de production. En outre, un diagramme de Venn généré pour comparer la CCB d’une eau de production avec son eau d’injection a révélé que seulement 4% des OTUs bactériennes sont communes à ces deux types d’eaux. L'analyse phylogénétique des séquences bactériennes indiquait que Alpha, Beta et Gammaproteobacteria étaient les principales classes retrouvées dans la plupart des échantillons d'eaux. Les séquences d'archées ont été obtenues seulement à partir des eaux de production et chaque puits avait une composition unique en communauté archaeal, appartenant principalement aux classes des Methanobacteria, Methanomicrobia, Thermoprotei et Halobactéries. Plusieurs genres bactériens recensés avaient déjà été rapportés comme dégradeurs de molécules et de polluants organiques complexes. Néanmoins, un grand nombre de séquences de bactéries et d'archées non classées ont été retrouvés dans ces échantillons analysés, ce qui indique que les eaux souterraines des champs pétrolifères pourraient abriter de nouvelles espèces microbiennes non encore décrite jusqu'à l’heure actuelle
Homology modelling and bioinformatics analysis of haloarchaeal α-amylases : an overview of proteins haloadaptation and stability
(2013) Khemili, Souad; Zorgani, Mohamed Amine; Kebbouche-Gana, Salima; Lenchi, Nesrine
Identification and phylogenetic analyses of anaerobic sulfidogenic bacteria in two Algerian oilfield water injection samples
(Taylor & Francis, 2021) Lenchi, Nesrine; Kebbouche-Gana, Salima; Servais, Pierre; Gana, Mohammed Lamine; Llirós, Marc
Corrosion of metallic oilfield pipelines by microorganisms is a costly but poorly understood phenomenon. For the first time, sulfidogenic communities in injection waters of two Algerian oilfields, Tin Fuin Tabankort (IT3) and Stah (IS2) were examined using the 16S rRNA gene cloning and sequencing approach. Water samples were inoculated into selective medium for sulfate-reducing bacteria and incubated under anaerobic conditions at 45 °C. The total number of culturable sulfidogenic microorganisms in the samples obtained from the two sampled waters (IT3 and IS2) was 2.4 × 105 cells/mL and 3.9 × 104 cells/mL, respectively. Scanning electron microscopy analyses showed different morphological forms reflecting the diversity of sulfidogenic communities. 16S rRNA gene sequencing and phylogenetic diversity analyses revealed that both water reservoirs harbor large amounts of anaerobic bacteria. However, a majority of all the sequences analyzed (e.g., 34% in the IS2 and 84% in the IT3 samples) were not assigned to any known bacterial group, suggesting that subsurface waters harbor very large sulfidogenic anaerobic microbial communities of as yet undescribed bacterial phyla. Proteobacteria were found to be the most dominant phylum in the IS2 sample (49%); however, no Proteobacteria were detected at the IT3 production well. The Firmicutes phylum (10%) was detected in the two water samples, whereas Bacteroidetes phylum (7%) was retrieved only in IT3. The most abundant related genera were: Desulfotomaculum, Porphyrobacter, Hyphomicrobium, Acidocella, Comamonas, Ramlibacter, Pseudomonas, Enterobacter and Flavitalea. No shared operational taxonomic units were observed among the two samples analyzed, demonstrating the uniqueness of each subsurface water well. This study demonstrates the diversity of the sulfidogenic bacteria that might play a critical role in the souring mediated corrosion of metallic oilfield pipelines. This information could help oilfield companies develop better anticorrosion treatments and strategies
Microbacterium algeriense sp. nov., a novel actinobacterium isolated from Algerian oil production waters
(Microbiology Society, 2020) Lenchi, Nesrine; Anzil, Adriana; Servais, Pierre; Kebbouche-Gana, Salima; Gana, Mohamed Lamine
A non-motile, straight-rod-shaped, Gram-stain-positive and facultative anaerobic bacterium (i.e., strain G1T) was isolated from production waters from an Algerian oilfield. Growth was observed in the presence of 0.3-3.5 % (w/v) NaCl, at 20-50 °C and at pH 6.0-9.0. Results of phylogenetic analyses based on 16S rRNA gene sequences showed that strain G1T belonged to the genus Microbacterium. Strain G1 T was closely related to Microbacterium oxydans (DSM 20578T) and Microbacterium maritypicum (DSM 12512T) with 99.8 % sequence similarity and to Microbacterium saperdae (DSM 20169T) with 99.6 % sequence similarity. Strain G1 T contained MK9, MK10, MK11, MK12 and MK13 as respiratory quinones, and phosphatidylglycerol, diphosphatidylglycerol and glycolipid as the major polar lipids. The major cellular fatty acids were anteiso-C15:0, iso-C16:0 and anteiso-C17:0. The estimated DNA G+C content was 69.57 mol% based on its draft genome sequence. Genome annotation of strain G1T predicted the presence of 3511 genes, of which 3483 were protein-coding and 47 were tRNA genes. The DNA-DNA hybridization (DDH) and average nucleotide identity (ANI) values between strain G1T and M. oxydans (DSM 20578T) and M. maritypicum (DSM 12512T) were in both cases far below the respective species boundary thresholds (27.5 and 28.0 % for DDH; and 84.40 and 84.82% for ANI, respectively). Based on the data presented above, strain G1T was considered to represent a novel species for which the name Microbacterium algeriense is proposed with the type strain G1T (=DSM 109018T=LMG 31276T)
Microbial community composition in production and injection waters from Algerian oilfields
(2013) Lenchi, Nesrine; Inceoğlu, Özgül; Kebbouche-Gana, Salima; Garcia-Armisen, Tamara
Oil recovery from Algerian petroleum sludge using indigenous bacterium: an environmentally sustainable method for handling oily sludge
(Springer, 2025) Lenchi, Nesrine; Benchouk, Amina; Ighilahriz, Kahina; Alilat, Abdenour; Kebbouche-Gana, Salima; Khemili-Talbi, Souad
One type of solid emulsified waste produced by the petroleum industry is oily sludge. Due to the high levels of hazardous substances it contains, it poses a significant risk to human health and the environment. Therefore, treatment is necessary to reduce its toxicity. Crude oil, which has a high recycling value, accounts for a significant proportion of oily sludge. This study aims to use the indigenous bacterium Enterococcus faecium NL 6 to produce a biosurfactant for use in oil recovery from sludge. This strain can produce biosurfactant using low-cost, renewable substrates such as whey, reaching an E24 of 72% and achieving a significant reduction in surface tension (27.2 mN/m). This extracellular biosurfactant was produced at a concentration of 32 mg/L and remains stable under extreme conditions of temperature, pH and salinity. Identified as rhamnolipids, the biosurfactants were able to recover 95% of the oil from oily sludge sampled from crude oil storage tanks in just a few hours (4 h). Gas chromatography has demonstrated the presence of normal alkanes in the crude oil extracted from the sludge, thereby indicating its potential for reuse as an energy source. Incorporating 5% of the recovered oil into the crude oil enhances its efficiency, resulting in a calorific value of 10,324.675 kcal/kg. Given the economic and environmental advantages of biosurfactants, the resulting rhamnolipid can be considered an effective, efficient and reliable washing agent for the recovery and treatment of oily sludge waste.
Phenotypic characterization, 16s RNA identification of cultivable on-obligate halophilic bacterial communities from a Tinsilt sebkha, wilaya of Oum El Bouaghi (Algeria) and screening for extracellulars hydrolases and biosurfactants
(2013) Kebbouche-Gana, Salima; Lenchi, Nesrine; Gana, Mohamed Lamine; Khemili, Souad
Production de biosurfactants par Haloarcula sp. souche D21 en conditions salines à partir de milieux de culture à base de lactosérum et des eaux de trempage de maïs (corn steep liquor)
(2012) Kebbouche-Gana, Salima; Khemili, Souad; Lenchi, Nesrine; Akmoussi-Toumi, Siham; Ferioune, I.
Production of an extracellular lipase from a halophilic isolate, Idiomarina sp.
(2013) Akmoussi-Toumi, Siham; Kebbouche-Gana, Salima; Lenchi, Nesrine
Production of biosurfactant on crude date syrup under saline conditions by entrapped cells of Natrialba sp. strain E21, an extremely halophilic bacterium isolated from a solar saltern (Ain Salah, Algeria)
(Springer, 2013) Kebbouche-Gana, Salima; Gana, Mohamed Lamine; Ferrioune, Imen; Khemili, Souad; Lenchi, Nesrine; Akmoussi-Toumi, Siham; Bouanane-Darenfed, Nabila Amel; Djelali, Nacer-Eddine
A bacterial strain E21 was isolated from a sample of water collected in the salt lake located close to Ain Salah, Algeria. The analysis of 16S rRNA gene sequence had indicated that the strain had 93 % sequence similarity with the genus Natrialba sp. strain E21 (Gen- Bank, FR750525.1) and was considered extremely halo- philic. Production of biosurfactant by the strain E21 with free and entrapped cells was investigated using soluble starch in the saline conditions. Biosurfactant synthesis was followed by measuring the surface tension and emulsifying index 9 days under optimal conditions (40 C, pH 7). Some diffusional limitations in alginate and agar beads affected the kinetics of biosurfactant production when compared to that obtained with free cells culture. The minimum values of surface tension were 27 and 30 mN m - 1 achieved after 9 days with free and immobilized cells, respectively, while the corresponding maximum E24 values were 65.3 and 62.3 %, respectively. The re-use of bacterial cells along with the limited cell losses provided by the immobilized system might lead to significant reduction of the biosur- factant production cost
Screening and Docking Molecular Studies of Natural Products Targeting overexpressed Receptors HER-2 in Breast Cancer
(Razi Vaccine and Serum Research Institute, 2025) Lenchi, Nesrine; Maouche, Naima; Khemili-Talbi, Souad
Breast cancer is the first cancer to affect a community. Because of its extremely high mitotic activity, breast cancer that tests positive for HER 2 is considered to have a poor prognosis. Due to the side effects of chemical drugs, patients are increasingly turning to natural medicine, such as phytotherapy and nutritherapy. The study uses a bioinformatics approach (molecular docking) to searchfor new, non-toxic anti-cancer inhibitors. The studyscreens 102 ligands from natural and dietary compounds that are likely to interact with the HER-2. The virtual screening results of the allow us to select the 23 best compounds which can be proposed as the most effective HER-2 inhibitors. Lycopene would be a very promising ligand which presents a DeltaG of -9.82 kcal/mol. Other promising ligands include beta-carotene (DeltaG of -8.58), P-cumaric acid kcal/mol (DeltaG of -8.57) and Curcumin (DeltaG of -8.46). Other compounds, luteolin, anacardium (Anacardic acid),and alpha-Tocopherol, were found to have the strongest inhibitory effects with DeltaG values of -7.92 kcal/mol, - 7.89 kcal/mol, and-7.85 kcal/mol, respectively. These compounds act directly on residues keys found in the hydrophobic pocket II (ATP binding site) and the hydrophobic region (the αC-β4 loop) of the EGFR domain. Pinoresinol, Kaempferol and Caffeic acid have DeltaGs of -7.48 Kcal/mol, -6.88 Kcal/mol and -6.34 kcal/mol, respectively. These three ligands are specific to the conserved regions of the HER-2 receptor and interact with the C-terminal, the C-lobe activation loop and the N-lobe P loop of the tyrosine kinase domain, respectively. Lapatinib (chemical compound) and quercetin (natural compound) have DeltaG of -7.58 kcal/mol and -7.28 kcal/mol, respectively, form a hydrogen bond with the same residue in the hydrophobic region. All the natural molecules seem very promising and, after in vitro/in vivo tests, could constitute good substitutes for the chemotherapies which are currently used to treat breast cancers as well as other cancers. Copy right
Simultaneous removal of crude oil and heavy metals by highly adapted bacterial strain Cutibacterium sp. NL2 isolated from Algerian oilfield
(Springer Science and Business Media Deutschland GmbH, 2024) Lenchi, Nesrine; Ahmedi, Wissam Nour El Houda; Llirós, Marc
Investigating the ability of bacteria to simultaneously enhance hydrocarbon removal and reduce heavy metals’ toxicity is necessary to design more effective bioremediation strategies. A bacterium (NL2 strain) isolated from an Algerian oilfield was cultivated on crude oil as sole carbon and energy sources. Molecular analyses of the 16S rRNA gene sequence placed the strain within the Cutibacterium genera. This isolate was able to tolerate up to 60% of crude oil as sole carbon source. Chemical analyses (GC-MS) evidenced that strain NL2 was able to degrade 92.22% of crude oil (at optimal growing conditions: pH 10, 44 °C, 50 g L−1 NaCl, and 20% of crude oil (v/v) as sole carbon source) in only 7 days. NL2 isolate was also able to produce biosurfactants with reduction of surface tension of growing media (29.4 mN m−1). On the other hand, NL2 strain was able to tolerate high lead (Pb) and copper (Cu) concentrations (up to 60 mM). In fact, NL2 cultivated in the presence of 20% of crude oil, and 0.48 mM of Pb was able to reduce Pb concentration by a 41.36%. In turn, when cultivated on high Pb concentration (15 mM), the strain was able to remove 35.19% of it and 86.25% of crude oil, both in a time frame of 7 days. Our findings suggest that Cutibacterium strain NL2 is able to efficiently use and remove a wide range of crude oil substrates in presence of high Pb concentration. Accordingly, NL2 strain is of extreme interest from a biotechnological standpoint.
Valorisation de sous produits agroalimentaires pour la production de biosurfactants
(2014) Kebbouche-Gana, Salima; Khemili, Souad; Akmoussi-Toumi, Siham; Lenchi, Nesrine