Publications Scientifiques
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Item 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, NesrineOlea 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 industriesItem 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, SouadOne 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.Item Chitosan nanoparticles with controlled size and zeta potential(John Wiley and Sons Inc, 2023) Benamer-Oudih, Samah; Tahtat, Djamel; Nacer Khodja, Assia; Mahlous, Mohamed; Hammache, Yasmina; Guittoum, Abd-Errahim; Kebbouche-Gana, SalimaOptimization of chitosan nanoparticles (ChNs) production process employing a 2(5–2) fractional factorial design was performed to analyze the influence of viscosity average molecular weight (40–120 kDa), the initial concentration of chitosan (2–5 g/L), the initial tripolyphosphate (TPP) concentration (0.8–1.2 g/L), the ratio chitosan/TPP (4/1–10/1) (V/V), and the stirring speed (300–700 rpm), on final nanoparticles size and zeta potential. The measured responses of average particle size and surface charge were determined on Zetasizer Nano ZS. ChNs were prepared using ionotropic cross-linking of chitosan and TPP and were characterized by Fourier-transform infrared spectroscopy (FTIR), X-ray powder diffraction (XRD), and differential scanning calorimetry (DSC). The experiments showed that the size of synthesized nanoparticles depended on initial concentration and molecular weight of chitosan, TPP concentration and stirring speed within the chosen levels. However, the zeta potential was significantly influenced by chitosan molecular weight, chitosan concentration and stirring speed. The FTIR analysis confirmed the interaction between negative charge of TPP with positive charge of chitosan through the appearance of new peaks at 1222 and 895 cm−1 in produced ChNs. XRD and DSC analysis were used to evaluate the effect of crosslinking of chitosan on crystal structure of ChNsItem Electrocatalytic activity survey of some cathode materials for the reduction of nitrites and nitrates in aqueous solution(Publishing House of the Romanian Academy, 2020) Angar, Yassmina; Daoudi, Sofiane; Kebbouche-Gana, Salima; Djelali, Nacer-EddineThe electrochemical techniques are the subject of increasing interest on the environmental remediation methods thanks to their efficiency and their selectivity. It was classified among the cleanest methods because it does not produce sludge and undesirable intermediate byproducts. For these reasons, we have chosen this technology for the reduction of nitrites and nitrates ions from aqueous solutions. The objective of our study is the comparison of several cathodes materials performances, in order to promote an optimal electro-reduction of these ions. Indeed, we have used the copper, graphite, stainless steel and zinc as cathodes; among them, we have selected the most efficient on which we have optimized the operational conditions. The results suggested that the copper cathode was the most efficient for the reduction of both tested ions compared to the other tested materials. Therefore, the optimization of operational conditions allows us to fixed them at: scan rate=50 mV/s, initial effluent concentration=100 mg/L, pH=7 and potential range of the cyclic voltammetry scanning of [-1,+1]V/SCE for both ions. Under these optimal parameters, the reduction yield after 45min was important that can achieve 96.5% and 99% for nitrites and nitrates respectivelyItem 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, MarcCorrosion 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 strategiesItem A Comprehensive Study on Crude Methanolic Extract of Daphne gnidium L. as Effective Corrosion Inhibitors of Mild Steel Induced by SRB Consortium(Springer, 2019) Djouahra-Fahem, Djamila; Angar, Yassmina; Lamine Mohamed, Gana; Khoukhi, Faiza; Kebbouche-Gana, SalimaThe aim of the present work is the evaluation of effect of methanolic extract obtained from Daphne gnidium against biocorrosion caused by sulphate-reducing bacteria (SRB). Herein, the study of the influence of SRB consortium has been realized on the biological and electrochemical properties of the carbon steel API5LX60 immersed in water sample obtained from an Algerian oil field separator. The monitoring of the treatment effects on the SRB performance using kits test and weight loss methods showed a positive effect of the methanolic extract of D. gnidium as a corrosion inhibitor at a concentration of 0.8 g/L. In the other hand, the weight loss test has generated an efficiency rate of 95.99% at a concentration of 1.6 g/L. A linear polarization resistance approved these results, and they have given a yield of 91.14% with a polarization resistance value of 28.9 kΩ cm2 at a concentration of 0.25 g/L.Item Efficiency Evaluation of Anti-corrosion Treatment of Carbon Steel by Extracts of Red Algae Collected from Mediterranean Coast(Revista de Chimie SRL, 2021) Khoukhi, Faiza; Kebbouche-Gana, Salima; Djelali, Nacer Eddine; Gana, Mohamed LamineThe paper presents the assessment of inhibition effectiveness of biomolecules extracted from red seaweed against biocorrosion in the petroleum industry. The first objective of this study was to obtain extracts (A, B and C, prepared respectively from red algae species: Corallina ellongata, Gymnogongrus crenulatus and Pterocladia capillacea) by ethanol extraction method. The infrared spectra of the three extracts confirmed the presence of amine derivatives molecules known by their anti-corrosion inhibiting powers. The second objective was based on the identification of physico-chemical characteristics of the extracts and thus revealing their inhibitory and / or bactericidal power in bacterial corrosion of carbon steel in injection water contaminated with sulfato-reducing bacteria. Biological test of all extracts gave a concentration upto 10 germs/mL in contaminated water by sulfato-reducing bacteria during 28 days of incubation at 37°C. Evolution in time of the open-circuit potential showed a longer incubation time for electrolyte with extracts, whereas the stabilization time was shorter. Current corrosion density, polarization resistance, charge transfer resistance and double layer capacity were determined by using linear polarizarion resistance technique and electrochemical impedance spectroscopy. The corrosion protection efficiency of extract obtained from Gymnogongrus crenulatus (extract B) reached a maximum protective capacity of 99.69% at 5 ppm in the injection water.Item Biodegradation of Petroleum hydrocarbons and Biosurfactant production by an extremely halophilic Archaea Halovivax sp. A21(Aljest, 2017) Khemili-Talbi, S.; Kebbouche-Gana, Salima; Akmoussi-Toumi, S.; Gana, M.L.; Lahiani,S.; Ferrioune ,I.; Angar,Y.Over the recent few years, biosurfactant has played an important role in the industrial application especially in oil recovery; even in high salinity conditions. The potential of biosurfactant production by the extreme halophilic archaeon Halovivax sp. A21 in the presence of petroleum hydrocarbons (2% v/v) as sole carbon source at high salinity (25% NaCl) has been investigated. The results show the ability of Halovivax sp. A21 to grow and reduce surface tension under an optimum range of pH (7-9), salinities (15-35% NaCl) and temperature (40-45°C) for an optimized volume of 100 ml of the medium for 1000 ml capacity Erlenmeyer flasks with an optimum agitation of 120 rpm. The rates of biosurfactant production on petroleum hydrocarbons were enhanced with increasing NaCl concentration in the medium with an optimum of 25%. Biosurfactant production by Halovivax sp. A21 showed high emulsifying activity (more than 80%) and decreased surface tension (24.5 mN/m). The stability of the produced biosurfactant was determined by different physico-chemical conditions like pH, temperature and salinity. Moreover, the partial purification of the derived biosurfactant by silica gel column chromatography and Thin-layer chromatography revealed that it belongs to the lipopeptide group. Although both catechol dioxygenases participated in the degradation of petroleum hydrocarbons, more induction of catechol 1,2 dioxygenase was observed than the catechol 2,3 dioxygenase which indicated the predominance of the ortho cleavage pathways in the petroleum hydrocarbons degradation by the halophilic strain Halovivax sp. A21. The results demonstrated that strain Halovivax sp. A21 was able to increase the bioavailability of insoluble hydrocarbons, thus facilitating their uptake and their biodegradation even at high salt concentration. Likewise, the search of novel biosurfactants in extremophiles, or the use of microorganisms that present excellentItem Insights into the draft genome sequence of bioactives-producing Bacillus thuringiensis DNG9 isolated from Algerian soil-oil slough(2018) Daas, Mohamed Seghir; Rosana, Albert Remus R.; Acedo, Jeella Z.; Douzane, Malika; Nateche, Farida; Kebbouche-Gana, Salima; Vederas, John C.Bacillus thuringiensisis widely used as a bioinsecticide due to its ability to form parasporal crystals containingproteinaceous toxins. It is a member of theBacillus cereussensulato, a group with low genetic diversity butproduces several promising antimicrobial compounds.B. thuringiensisDNG9, isolated from an oil-contaminatedslough in Algeria, has strong antibacterial, antifungal and biosurfactant properties. Here, we report the 6.06 Mbpdraft genome sequence ofB. thuringiensisDNG9. The genome encodes several gene inventories for thebiosynthesis of bioactive compounds such as zwittermycin A, petrobactin, insecticidal toxins, polyhydroxyalkanoatesand multiple bacteriocins. We expect the genome information of strain DNG9 will provide another model system tostudy pathogenicity against insect pests, plant diseases, and antimicrobial compound mining and comparativephylogenesis among theBacillus cereussensulatogroupItem Valorization of olive tree leaves : phytochemical and pharmacological characterizations, selection of extracts and formulation of herbal cream(2021) Bakdi, Hadjer; Kebbouche-Gana, Salima; Djelali, N.; Louhab, K.; Yahiaoui, K.Olive tree (Olea EuropeaL.) is one of the most important crops in the Mediterranean countries. The global olive oil industry annually generates many tons of olive leaves as waste.The present study aims at a valorisation of Algerian olive leaves harvested from the region of Bouirafor therapeutic use. In order to evaluate the biological effects of the wild olive tree, chemical characterization tests of the leaves were carried out in the Natural Substances Laboratory of Saidal group according to their validated protocols drawn from the French pharmacopoeia. A phytochemical screening has been realized and whose purpose is to refer to the extraction, screening and identification of the medicinally active substances in the plant. Different extractions have been carried out in several solvents in order to extract bioactive molecules from the leaves using several solvents. Subsequently, a pharmacological characterization has been completed by determining the following: antioxidant activity of the extracts was evaluated in vitro by the DPPH method, anti-inflammatory activity was studied in vivo by induction of carrageenan oedema; the antibacterial activity was achieved by the agar medium diffusion method. Finally, we formulated an anti-inflammatory and antibacterial ointments based on the results obtained