Taha Menasria - Profile on Academia.edu (original) (raw)

Papers by Taha Menasria

World Journal of Microbiology and Biotechnology , 2019

This paper aims to characterize halophilic bacteria inhabiting Algerian Saline Ecosystems (Sebkha... more This paper aims to characterize halophilic bacteria inhabiting Algerian Saline Ecosystems (Sebkha and Chott) located in arid and semi-arid ecoclimate zones (Northeastern Algeria). In addition, screening of enzymatic activities, heavy metal tolerance, and antagonistic potential against phytopathogenic fungi were tested. A total of 74 bacterial isolates were screened and phylogenetically characterized using 16S rRNA gene sequencing. The results showed a heterogeneous group of microorganisms falling within two major phyla, 52 strains belonging to Firmicutes (70.2%) and 22 strains (30.8%) of γ-Proteobacteria. In terms of main genera present, the isolates were belonging to Bacillus, Halobacillus, Lentibacillus, Oceanobacillus, Paralio-bacillus, Planomicrobium, Salicola, Terribacillus, Thalassobacillus, Salibacterium, Salinicoccus, Virgibacillus, Halomonas, Halovibrio, and Idiomarina. Most of the enzyme producers were related to Bacillus, Halobacillus, and Virgibacillus genera and mainly active at 10% of growing salt concentrations. Furthermore, amylase, esterase, gelatinase, and nuclease activities ranked in the first place within the common hydrolytic enzymes. Overall, the isolates showed high minimal inhibitory concentration values (MIC) for Ni 2+ and Cu 2+ (0.625 to 5 mM) compared to Cd 2+ (0.1 to 2 mM) and Zn 2+ (0.156 to 2 mM). Moreover, ten isolated strains belonging to Bacillus, Virgibacillus and Halomonas genera, displayed high activity against the pathogenic fungi (Botrytis cinerea, Fusarium oxyporum, F. verticillioides and Phytophthora capsici). This study on halophilic bacteria of unexplored saline niches provides potential sources of biocatalysts and novel bioactive metabolites as well as promising candidates of biocontrol agents and eco-friendly tools for heavy metal bioremediation.

EXCLI Journal, 2020

The increased incidence of invasive infections and the emerging problem of drug resistance partic... more The increased incidence of invasive infections and the emerging problem of drug resistance particularly for commonly used molecules have prompted investigations for new, safe and more effective microbial agents. Actinomycetes from unexplored habitats appear as a promising source for novel bioactive compounds with a broad range of biological activities. Thus, the present study aimed to isolate effective wetland-derived actinomycetes against major pathogenic fungi and bacteria. Water samples were collected from various locations of Fetzara Lake, Algeria. Thereafter, an actinomycete designated ActiF450 was isolated using starch-casein-agar medium. The antimicrobial potential of the newly isolated actinomycete was screened using the conventional agar cylinders method on Potato Dextrose Agar (PDA) against various fungal and bacterial pathogens. A wetland-derived Streptomyces sp. Actif450 was identified as Streptomyces malaysiensis based on its physiological properties, morphological characteristics, and 16S rDNA gene sequence analysis. The antimicrobial activity of Streptomyces sp. ActiF450 showed potent and broad-spectrum activity against a range of human fungal pathogens including moulds and yeasts, such as Arthroderma vanbreuseghemii, Aspergillus fumigatus, A. niger, Candida albicans, C. glabarta, C. krusei, C. parapsilosis, Fusarium oxysporum, F. solani, Microsporum canis, Rhodotorula mucilaginous and Scodapulariopsis candida. In addition, high antibacterial activity was recorded against pathogenic staphylococci. The novel Streptomyces sp. ActiF450 may present a promising candidate for the production of new bioactive compounds with broad-spectrum antimicrobial activity.

The Journal of Infection in Developing Countries (JIDC), Apr 4, 2019

Introduction: Pseudomonas aeruginosa is one of the most common nosocomial pathogens, known with a... more Introduction: Pseudomonas aeruginosa is one of the most common nosocomial pathogens, known with a wide resistance to antimicrobials. Carbapenemases producing Pseudomonas aeruginosa is a growing global public health concern as this pathogen is easily transmissible among patients. Metallo-Beta-lactamases is the most important class of these carbapenemases with their broad-spectrum resistance profile. This study was conducted to investigate the prevalence of MBL-producing P. aeruginosa collected in an Algerian hospital. Methodology: All Metallo-β-lactamase (MBL)-producing P. aeruginosa isolates recovered from patients during a 2 years period (2015-2016) were studied using a combination of phenotypic and molecular typing methods (susceptibility testing, molecular characterization of carbapenemase-encoding genes, multi-locus sequence typing and pulsed-field gel electrophoresis). Results: A total of twenty-six MBL producing P. aeruginosa of 188 isolates were investigated. The burns unit ranked in the first position of the majority of identified cases with 73.07%. About 73.07% of total MBL isolates were mainly isolated from pus samples. The studied isolates were subjected to the molecular typing, in which 4 different Dra1-PFGE patterns and 3 sequences type were assigned (ST244, ST381, and ST1076), and all isolates were revealed positive for VIM-4. Conclusions: We report the third description of blaVIM-4 in Algeria indicating the emergence and spread of carbapenemase-encoding genes among P. aeruginosa in the hospital environment.

Journal of Advanced Research, 2018

A phenotypic characterization of thirteen root nodule bacteria recovered from wild legumes (Genis... more A phenotypic characterization of thirteen root nodule bacteria recovered from wild legumes (Genista microcephala and Argyrolobium uniflorum) growing in arid eco-climate zones (Northeastern Algeria) was conducted using analysis of sixty-six phenotypic traits (carbohydrate and nitrogen assimilation, vitamin requirements, growth temperature, salinity/pH tolerance and enzyme production). Furthermore, SDS-PAGE profiles of total cell protein, antibiotic susceptibility and heavy metal resistance were performed. The results showed that the isolates can grow at pH 4 to 10, salt concentration (0-5%) and temperature up to 45 °C. The rhizobia associated with Genista microcephala and Argyrolobium uniflorum were able to produce different hydrolytic enzymes including cellulose, pectinase and urease, with remarkable tolerance to toxic metals such as zinc, lead, copper, and mercury. Numerical analysis of the phenotypic characteristics revealed that the rhizobial isolates formed four main distinct groups showing high levels of similarity with Gammaproteobacteria. The salt tolerant and heavy metals resistance patterns found among the indigenous rhizobial strains are reflecting the environmental stresses pressure and make the strains good candidates for plant successful inoculation in arid areas.

Journal of King Saud University - Science, 2018

Actinomycetes from unexplored habitats are considered as a promising source for novel bioactive c... more Actinomycetes from unexplored habitats are considered as a promising source for novel bioactive compounds with a broad range of biological activities. A study was carried out to isolate and identify rare acti-nomycetes producing antimicrobial from a natural wetland. Water samples from Fetzara Lake (North eastern-Algeria) were collected and subjected to rare actinomycetes isolation using different rich media. Eight selected actinomycetes were screened in vitro for hydrolytic enzymes, antibacterial and anticandi-dal activities. Based on the 16S rRNA sequencing, the eight actinomycetes isolates were categorized into four different rare genera Actinomadura, Nocardia, Nonomuraea and Micromonospora. Interestingly, significant anticandidal and antibacterial activities against both Gram-positive and Gram-negative bacteria were observed. Furthermore, the actinomycetes isolates were able to produce different hydrolytic enzymes with potential industrial and food processing applications such as amylase, cellulase, protease, and lipase. Overall, the study revealed that the selected aquatic rare actinomycetes recovered from Fetzara Lake presented good candidates to be explored as new sources of bioactive compounds.

Microbiological Research, Mar 2018

The diversity of haloarchaea associated with different dry salt lakes in northeastern Algeria was... more The diversity of haloarchaea associated with different dry salt lakes in northeastern Algeria was investigated together with their potential of hydrolytic enzyme production. A total of 68 aerobic halophilic archaea were isolated from saline sediments. Based on the 16S rRNA gene sequencing, the isolates were assigned to seven phylotypes within the class Halobacteria, namely Haloarcula, Halococcus, Haloferax, Halogeometricum, Haloterrigena, Natrialba, and Natrinema. The results showed that Haloferax group was found to be dominant in all samples (30 isolates) (44%) with high diversity, followed by Halococcus spp. (13%) (9 isolates). All phylotypes are extreme halophiles and thermotolerant with the ability to grow at temperatures up to 48 °C. In addition, the screening for extracellular halophilic enzymes showed that 89.7% of the isolates were able to produce at least two types of the screened enzymes. The strains producing esterase, gelatinase, inulinase, cellulase and protease activities were the most diverse functional group. These data showed an abundant and diverse haloarchaeal community, detected in Algerian wetland ecosystems, presenting a promising source of molecules with important biotechnological applications.

International Biodeterioration & Biodegradation, Dec 2017

This study was car­ried out to pro­vide an overview of the fun­gal load in Al­ger­ian tra­di­tion... more This study was car­ried out to pro­vide an overview of the fun­gal load in Al­ger­ian tra­di­tional baths (Ham­mams) as well as to iso­late and iden­tify the main path­o­genic fungi. Over a pe­riod of four months, ten baths were ex­am­ined and screened for fun­gal con­t­a­m­i­na­tion from sev­eral parts of the hot steamy rooms (floor, wall, door, air and mar­ble mas­sage plat­form). In to­tal, 7157 fungi iso­lates were re­cov­ered from the sur­veyed Ham­mams and the most abun­dant molds were Peni­cil­lium spp. (45.12%) fol­lowed by As­pergillus spp. (28.80%). In ad­di­tion, molds flora in tra­di­tional baths was char­ac­ter­ized by a large num­ber of hy­drophilic species like Cla­dospo­rium, Fusar­ium, Rhi­zo­pus, Mu­cor and Al­ternaria. Eight can­dida-like ap­peared fre­quently (C. al­bi­cans, C. glabrata, C. trop­i­calis, C. lipoly­t­ica, Ge­ot­richum sp., Tri­chosporon sp., Rhodotorula sp. and Cryp­to­coc­cus sp.) of which C. al­bi­cans was the com­mon iso­lated yeast (35.14%). The re­sults in­di­cate a sig­nif­i­cant dif­fer­ence (p = 0.007) in species rich­ness be­tween molds and yeasts and their dis­tri­b­u­tion var­ied sig­nif­i­cantly among sam­pled po­si­tions in baths. AN­COVA re­vealed a sig­nif­i­cant in­crease in fun­gal loads re­lated to the av­er­age num­ber of cus­tomers and mean open­ing year of the Ham­mams, in con­trast with lo­cal­ity (fa­vored or pop­u­lar dis­trict). This study in­di­cates that Ham­mams pre­sent a po­ten­tial source of path­o­genic fungi which may im­pose a real threat on pub­lic health

Original Research Article, Nov 2015

Earthworms are important soil macroinvertebrates and are often used in assessing of soil pollutio... more Earthworms are important soil macroinvertebrates and are often used in assessing of soil pollution. The present study was conducted in order to investigate the effect of two compounds, triple superphosphate TSP (fertilizer), sekator (herbicide) and their mixture at two agricultural doses on a Lumbricus terrestris population. Neurotoxicity (Acetylcholinesterase, AChE), metabolisation (glutathione-S-transferase GST), glutathione (GSH), and protein content were evaluated as biomarkers. Treated earthworms with sekator showed a non-significant increase of protein content (P>0.05). In contrast, protein content increased significantly (P<0.0001) up to (104.75±4.75 and 109.09±5.4 μg/worm) after 72h of exposure with TSP and the mixture respectively. As compared to TSP exposure, sekator in mixture substantially decreased AChE activity. In control series, the GST activities and GSH concentrations remain stable after 72h while sekator and TSP induced the biomarker responses, which was proportional to exposure time and administered dose. Non significant correlations were recorded between AChE and GSH, GST and the protein contents in most interactions. The obtained results indicate that application of sekator in mixture with triple superphosphate could have harmful effects on earthworms since caused significant changes in measured biomarkers.

Research Article, Mar 15, 2015

In the present study, an attempt is made to evaluate the kinetics of biological phosphate removal... more In the present study, an attempt is made to evaluate the kinetics of biological phosphate removal using a bacterial consortium of activated sludge, as well as screening for dominant polyphosphates accumulating bacteria. The results showed an efficient phosphate uptake (P < 0.001) of the consortium, with rates related to the initial concentration of both phosphate and carbon sources. Short chain volatile fatty acids presented the suitable substrates for enhanced biological phosphorus removal, of which maximum yield reached 99.23% and 78.51% in basal salt medium supplemented with 0.5% of sodium acetate and lactate respectively. Fifteen phosphate-accumulating bacteria were isolated from the activated sludge and only four isolates were selected and characterized as Pseudomonas aeruginosa AS1, Moraxella lacunata AS2, Acinetobater junii AS3 and Alcaligenes denitrificans AS4. The highest efficiency of phosphate uptake using pure culture was achieved with Ac. junii AS3 (83.36) followed by P. aeruginosa AS1 (81.78%), Al. denitrificans AS4 (76.72%), and M. lacunata AS2 with 50.6%.

A study was performed to estimate the prevalence of the external bacterial flora of two domestic ... more A study was performed to estimate the prevalence of the external bacterial flora of two domestic cockroaches (Blattella germanica and Blatta orientalis) collected from households in Tebessa (northeast Algeria). Three major bacterial groups were cultured (total aerobic, enterobacteria, and staphylococci) from 14 specimens of cockroaches, and antibiotic susceptibility was tested for both Staphylococcus and Pseudomonas isolates. Culturing showed that the total bacterial load of cockroaches from different households were comparable (P < 0.001) and enterobacteria were the predominant colonizers of the insect surface, with a bacterial load of (2.1E+5 CFU/insect), whereas the staphylococci group was the minority. Twenty-eight bacterial species were isolated, and susceptibility patterns showed that most of the staphylococci isolates were highly susceptible to chloramphenicol, gentamycin, pristinamycin, ofloxacin, clindamycin, and vancomycin; however, Pseudomonas strains exhibited resistance to amoxicillin/clavulanic acid, imipenem, and the second generation antibiotic cephalosporin cefuroxime.

Research article, Jul 2014

Abstract- In the present study, a total of 108 of lactic acid bacteria (LAB) was isolated from Al... more Abstract- In the present study, a total of 108 of lactic acid bacteria (LAB) was isolated from Algerian traditional fermented dairy products (Jben, Klila, Raib and Lben) in order to evaluate their enzymatic activities (Proteolytic, α-amylase production, caseinolytic, lipolytic) and antimicrobial proprieties. Twelve representative isolates were selected and characterized with regard to their functional properties. The retained strains were identified using phenotypic and 16S rDNA gene analysis as; Lactococcus lactis subsp lactis (3 strains), L. lactis subsp. cremoris (1 strain), L. lactis subsp. lactis biovar. diacetylactis (2 strains), Lactobacillus plantarum (3 strains), Lactobacillus casei subsp. casei (2 strains) and Leuconostoc mesenteroides (1 strain). Lactococcus strains showed the greatest degree of acidifying and proteolytic activity. However, tow strains of Lactobacillus casei subsp. casei exhibited maximum caseinolytic activity. Furthermore, low lipolytic and amylolytic capacities were detected. The enzymatic potential evaluated with API ZYM system showed that all strains exhibited high Leucine arylamidase, Valine arylamidase and β-Galactosidase activities. Selected LAB were also tested for their antimicrobial activity against Listeria monocytogenes ATCC 7644 using agar well diffusion technique. All extracts of isolates were found to be fully inactivated by proteolytic enzymes, heat stable up to 100°C for 20 min and displayed inhibitory activity at pH from 3.0 to 10.0. Lactic acid bacteria isolated in this study play complex role in the traditional fermentation milk by their functional properties related to a specific enzyme spectrum, acidifying capacity, antimicrobial activities and probiotic properties.

Research Article, Jul 2014

Abstract- This study was carried out to isolate and identify bacterial flora from German cockroac... more Abstract- This study was carried out to isolate and identify bacterial flora from German cockroaches (Blattella germanica) collected from dwellings and health facilities in Tebessa city. A total of 187 bacteria were isolated from 46 cockroachs pecimens. The most common and abundant bacteria species belonged to Enterobacteria group (54.54%), while pathogens like Staphylococcus aureus as well as
Pseudomonas aeruginosa w isolated with a rate of 12.83 % and 4.81 %, respectively. The results indicated that B. germanica is a possible reservoir and carriers of bacterial pathogens via their bodies and thus may spread multiple drug resistance species.

Research Article, Dec 2013

The study was carried out in Tebessa (Northeast Algeria) to investigate antimicrobial susceptibil... more The study was carried out in Tebessa (Northeast Algeria) to investigate antimicrobial susceptibility of Salmonella isolated from poultry product and human patients. Antibiotic resistance profiles were detected against 25 selected antimicrobial agents using micro dilution method (MICs). Seventy-six Salmonella strains were selected and serotyped which Salmonella Enteritidis serovar was the most prevalent serotype. Over all, High level of resistance were noted with quinolones (nalidixic acid), non-wild types with fluoroquinolones (norofloxacin, ofloxacin, ciprofloxacin) and variable scaling values within colistin. Foodborne strains showed some trends to shift toward non-wild types with some beta-lactams and sulfamethoxasole/trimethoprim. Moreover, human serovars showed heterogeneity in susceptibility patterns indicating wide spread multi-drug resistance with quinolones, β-lactams (aminopenicillin, cefalosporin), aminoglycosides, tetracycline, and chloramphenicol. As a result, the relatively high resistance among the Salmonella lying in both human and poultry products could pose therapeutic and public health problems as potential vehicles of resistant Salmonella.

World Journal of Microbiology and Biotechnology , 2019

This paper aims to characterize halophilic bacteria inhabiting Algerian Saline Ecosystems (Sebkha... more This paper aims to characterize halophilic bacteria inhabiting Algerian Saline Ecosystems (Sebkha and Chott) located in arid and semi-arid ecoclimate zones (Northeastern Algeria). In addition, screening of enzymatic activities, heavy metal tolerance, and antagonistic potential against phytopathogenic fungi were tested. A total of 74 bacterial isolates were screened and phylogenetically characterized using 16S rRNA gene sequencing. The results showed a heterogeneous group of microorganisms falling within two major phyla, 52 strains belonging to Firmicutes (70.2%) and 22 strains (30.8%) of γ-Proteobacteria. In terms of main genera present, the isolates were belonging to Bacillus, Halobacillus, Lentibacillus, Oceanobacillus, Paralio-bacillus, Planomicrobium, Salicola, Terribacillus, Thalassobacillus, Salibacterium, Salinicoccus, Virgibacillus, Halomonas, Halovibrio, and Idiomarina. Most of the enzyme producers were related to Bacillus, Halobacillus, and Virgibacillus genera and mainly active at 10% of growing salt concentrations. Furthermore, amylase, esterase, gelatinase, and nuclease activities ranked in the first place within the common hydrolytic enzymes. Overall, the isolates showed high minimal inhibitory concentration values (MIC) for Ni 2+ and Cu 2+ (0.625 to 5 mM) compared to Cd 2+ (0.1 to 2 mM) and Zn 2+ (0.156 to 2 mM). Moreover, ten isolated strains belonging to Bacillus, Virgibacillus and Halomonas genera, displayed high activity against the pathogenic fungi (Botrytis cinerea, Fusarium oxyporum, F. verticillioides and Phytophthora capsici). This study on halophilic bacteria of unexplored saline niches provides potential sources of biocatalysts and novel bioactive metabolites as well as promising candidates of biocontrol agents and eco-friendly tools for heavy metal bioremediation.

EXCLI Journal, 2020

The increased incidence of invasive infections and the emerging problem of drug resistance partic... more The increased incidence of invasive infections and the emerging problem of drug resistance particularly for commonly used molecules have prompted investigations for new, safe and more effective microbial agents. Actinomycetes from unexplored habitats appear as a promising source for novel bioactive compounds with a broad range of biological activities. Thus, the present study aimed to isolate effective wetland-derived actinomycetes against major pathogenic fungi and bacteria. Water samples were collected from various locations of Fetzara Lake, Algeria. Thereafter, an actinomycete designated ActiF450 was isolated using starch-casein-agar medium. The antimicrobial potential of the newly isolated actinomycete was screened using the conventional agar cylinders method on Potato Dextrose Agar (PDA) against various fungal and bacterial pathogens. A wetland-derived Streptomyces sp. Actif450 was identified as Streptomyces malaysiensis based on its physiological properties, morphological characteristics, and 16S rDNA gene sequence analysis. The antimicrobial activity of Streptomyces sp. ActiF450 showed potent and broad-spectrum activity against a range of human fungal pathogens including moulds and yeasts, such as Arthroderma vanbreuseghemii, Aspergillus fumigatus, A. niger, Candida albicans, C. glabarta, C. krusei, C. parapsilosis, Fusarium oxysporum, F. solani, Microsporum canis, Rhodotorula mucilaginous and Scodapulariopsis candida. In addition, high antibacterial activity was recorded against pathogenic staphylococci. The novel Streptomyces sp. ActiF450 may present a promising candidate for the production of new bioactive compounds with broad-spectrum antimicrobial activity.

The Journal of Infection in Developing Countries (JIDC), Apr 4, 2019

Introduction: Pseudomonas aeruginosa is one of the most common nosocomial pathogens, known with a... more Introduction: Pseudomonas aeruginosa is one of the most common nosocomial pathogens, known with a wide resistance to antimicrobials. Carbapenemases producing Pseudomonas aeruginosa is a growing global public health concern as this pathogen is easily transmissible among patients. Metallo-Beta-lactamases is the most important class of these carbapenemases with their broad-spectrum resistance profile. This study was conducted to investigate the prevalence of MBL-producing P. aeruginosa collected in an Algerian hospital. Methodology: All Metallo-β-lactamase (MBL)-producing P. aeruginosa isolates recovered from patients during a 2 years period (2015-2016) were studied using a combination of phenotypic and molecular typing methods (susceptibility testing, molecular characterization of carbapenemase-encoding genes, multi-locus sequence typing and pulsed-field gel electrophoresis). Results: A total of twenty-six MBL producing P. aeruginosa of 188 isolates were investigated. The burns unit ranked in the first position of the majority of identified cases with 73.07%. About 73.07% of total MBL isolates were mainly isolated from pus samples. The studied isolates were subjected to the molecular typing, in which 4 different Dra1-PFGE patterns and 3 sequences type were assigned (ST244, ST381, and ST1076), and all isolates were revealed positive for VIM-4. Conclusions: We report the third description of blaVIM-4 in Algeria indicating the emergence and spread of carbapenemase-encoding genes among P. aeruginosa in the hospital environment.

Journal of Advanced Research, 2018

A phenotypic characterization of thirteen root nodule bacteria recovered from wild legumes (Genis... more A phenotypic characterization of thirteen root nodule bacteria recovered from wild legumes (Genista microcephala and Argyrolobium uniflorum) growing in arid eco-climate zones (Northeastern Algeria) was conducted using analysis of sixty-six phenotypic traits (carbohydrate and nitrogen assimilation, vitamin requirements, growth temperature, salinity/pH tolerance and enzyme production). Furthermore, SDS-PAGE profiles of total cell protein, antibiotic susceptibility and heavy metal resistance were performed. The results showed that the isolates can grow at pH 4 to 10, salt concentration (0-5%) and temperature up to 45 °C. The rhizobia associated with Genista microcephala and Argyrolobium uniflorum were able to produce different hydrolytic enzymes including cellulose, pectinase and urease, with remarkable tolerance to toxic metals such as zinc, lead, copper, and mercury. Numerical analysis of the phenotypic characteristics revealed that the rhizobial isolates formed four main distinct groups showing high levels of similarity with Gammaproteobacteria. The salt tolerant and heavy metals resistance patterns found among the indigenous rhizobial strains are reflecting the environmental stresses pressure and make the strains good candidates for plant successful inoculation in arid areas.

Journal of King Saud University - Science, 2018

Actinomycetes from unexplored habitats are considered as a promising source for novel bioactive c... more Actinomycetes from unexplored habitats are considered as a promising source for novel bioactive compounds with a broad range of biological activities. A study was carried out to isolate and identify rare acti-nomycetes producing antimicrobial from a natural wetland. Water samples from Fetzara Lake (North eastern-Algeria) were collected and subjected to rare actinomycetes isolation using different rich media. Eight selected actinomycetes were screened in vitro for hydrolytic enzymes, antibacterial and anticandi-dal activities. Based on the 16S rRNA sequencing, the eight actinomycetes isolates were categorized into four different rare genera Actinomadura, Nocardia, Nonomuraea and Micromonospora. Interestingly, significant anticandidal and antibacterial activities against both Gram-positive and Gram-negative bacteria were observed. Furthermore, the actinomycetes isolates were able to produce different hydrolytic enzymes with potential industrial and food processing applications such as amylase, cellulase, protease, and lipase. Overall, the study revealed that the selected aquatic rare actinomycetes recovered from Fetzara Lake presented good candidates to be explored as new sources of bioactive compounds.

Microbiological Research, Mar 2018

The diversity of haloarchaea associated with different dry salt lakes in northeastern Algeria was... more The diversity of haloarchaea associated with different dry salt lakes in northeastern Algeria was investigated together with their potential of hydrolytic enzyme production. A total of 68 aerobic halophilic archaea were isolated from saline sediments. Based on the 16S rRNA gene sequencing, the isolates were assigned to seven phylotypes within the class Halobacteria, namely Haloarcula, Halococcus, Haloferax, Halogeometricum, Haloterrigena, Natrialba, and Natrinema. The results showed that Haloferax group was found to be dominant in all samples (30 isolates) (44%) with high diversity, followed by Halococcus spp. (13%) (9 isolates). All phylotypes are extreme halophiles and thermotolerant with the ability to grow at temperatures up to 48 °C. In addition, the screening for extracellular halophilic enzymes showed that 89.7% of the isolates were able to produce at least two types of the screened enzymes. The strains producing esterase, gelatinase, inulinase, cellulase and protease activities were the most diverse functional group. These data showed an abundant and diverse haloarchaeal community, detected in Algerian wetland ecosystems, presenting a promising source of molecules with important biotechnological applications.

International Biodeterioration & Biodegradation, Dec 2017

This study was car­ried out to pro­vide an overview of the fun­gal load in Al­ger­ian tra­di­tion... more This study was car­ried out to pro­vide an overview of the fun­gal load in Al­ger­ian tra­di­tional baths (Ham­mams) as well as to iso­late and iden­tify the main path­o­genic fungi. Over a pe­riod of four months, ten baths were ex­am­ined and screened for fun­gal con­t­a­m­i­na­tion from sev­eral parts of the hot steamy rooms (floor, wall, door, air and mar­ble mas­sage plat­form). In to­tal, 7157 fungi iso­lates were re­cov­ered from the sur­veyed Ham­mams and the most abun­dant molds were Peni­cil­lium spp. (45.12%) fol­lowed by As­pergillus spp. (28.80%). In ad­di­tion, molds flora in tra­di­tional baths was char­ac­ter­ized by a large num­ber of hy­drophilic species like Cla­dospo­rium, Fusar­ium, Rhi­zo­pus, Mu­cor and Al­ternaria. Eight can­dida-like ap­peared fre­quently (C. al­bi­cans, C. glabrata, C. trop­i­calis, C. lipoly­t­ica, Ge­ot­richum sp., Tri­chosporon sp., Rhodotorula sp. and Cryp­to­coc­cus sp.) of which C. al­bi­cans was the com­mon iso­lated yeast (35.14%). The re­sults in­di­cate a sig­nif­i­cant dif­fer­ence (p = 0.007) in species rich­ness be­tween molds and yeasts and their dis­tri­b­u­tion var­ied sig­nif­i­cantly among sam­pled po­si­tions in baths. AN­COVA re­vealed a sig­nif­i­cant in­crease in fun­gal loads re­lated to the av­er­age num­ber of cus­tomers and mean open­ing year of the Ham­mams, in con­trast with lo­cal­ity (fa­vored or pop­u­lar dis­trict). This study in­di­cates that Ham­mams pre­sent a po­ten­tial source of path­o­genic fungi which may im­pose a real threat on pub­lic health

Original Research Article, Nov 2015

Earthworms are important soil macroinvertebrates and are often used in assessing of soil pollutio... more Earthworms are important soil macroinvertebrates and are often used in assessing of soil pollution. The present study was conducted in order to investigate the effect of two compounds, triple superphosphate TSP (fertilizer), sekator (herbicide) and their mixture at two agricultural doses on a Lumbricus terrestris population. Neurotoxicity (Acetylcholinesterase, AChE), metabolisation (glutathione-S-transferase GST), glutathione (GSH), and protein content were evaluated as biomarkers. Treated earthworms with sekator showed a non-significant increase of protein content (P>0.05). In contrast, protein content increased significantly (P<0.0001) up to (104.75±4.75 and 109.09±5.4 μg/worm) after 72h of exposure with TSP and the mixture respectively. As compared to TSP exposure, sekator in mixture substantially decreased AChE activity. In control series, the GST activities and GSH concentrations remain stable after 72h while sekator and TSP induced the biomarker responses, which was proportional to exposure time and administered dose. Non significant correlations were recorded between AChE and GSH, GST and the protein contents in most interactions. The obtained results indicate that application of sekator in mixture with triple superphosphate could have harmful effects on earthworms since caused significant changes in measured biomarkers.

Research Article, Mar 15, 2015

In the present study, an attempt is made to evaluate the kinetics of biological phosphate removal... more In the present study, an attempt is made to evaluate the kinetics of biological phosphate removal using a bacterial consortium of activated sludge, as well as screening for dominant polyphosphates accumulating bacteria. The results showed an efficient phosphate uptake (P < 0.001) of the consortium, with rates related to the initial concentration of both phosphate and carbon sources. Short chain volatile fatty acids presented the suitable substrates for enhanced biological phosphorus removal, of which maximum yield reached 99.23% and 78.51% in basal salt medium supplemented with 0.5% of sodium acetate and lactate respectively. Fifteen phosphate-accumulating bacteria were isolated from the activated sludge and only four isolates were selected and characterized as Pseudomonas aeruginosa AS1, Moraxella lacunata AS2, Acinetobater junii AS3 and Alcaligenes denitrificans AS4. The highest efficiency of phosphate uptake using pure culture was achieved with Ac. junii AS3 (83.36) followed by P. aeruginosa AS1 (81.78%), Al. denitrificans AS4 (76.72%), and M. lacunata AS2 with 50.6%.

A study was performed to estimate the prevalence of the external bacterial flora of two domestic ... more A study was performed to estimate the prevalence of the external bacterial flora of two domestic cockroaches (Blattella germanica and Blatta orientalis) collected from households in Tebessa (northeast Algeria). Three major bacterial groups were cultured (total aerobic, enterobacteria, and staphylococci) from 14 specimens of cockroaches, and antibiotic susceptibility was tested for both Staphylococcus and Pseudomonas isolates. Culturing showed that the total bacterial load of cockroaches from different households were comparable (P < 0.001) and enterobacteria were the predominant colonizers of the insect surface, with a bacterial load of (2.1E+5 CFU/insect), whereas the staphylococci group was the minority. Twenty-eight bacterial species were isolated, and susceptibility patterns showed that most of the staphylococci isolates were highly susceptible to chloramphenicol, gentamycin, pristinamycin, ofloxacin, clindamycin, and vancomycin; however, Pseudomonas strains exhibited resistance to amoxicillin/clavulanic acid, imipenem, and the second generation antibiotic cephalosporin cefuroxime.

Research article, Jul 2014

Abstract- In the present study, a total of 108 of lactic acid bacteria (LAB) was isolated from Al... more Abstract- In the present study, a total of 108 of lactic acid bacteria (LAB) was isolated from Algerian traditional fermented dairy products (Jben, Klila, Raib and Lben) in order to evaluate their enzymatic activities (Proteolytic, α-amylase production, caseinolytic, lipolytic) and antimicrobial proprieties. Twelve representative isolates were selected and characterized with regard to their functional properties. The retained strains were identified using phenotypic and 16S rDNA gene analysis as; Lactococcus lactis subsp lactis (3 strains), L. lactis subsp. cremoris (1 strain), L. lactis subsp. lactis biovar. diacetylactis (2 strains), Lactobacillus plantarum (3 strains), Lactobacillus casei subsp. casei (2 strains) and Leuconostoc mesenteroides (1 strain). Lactococcus strains showed the greatest degree of acidifying and proteolytic activity. However, tow strains of Lactobacillus casei subsp. casei exhibited maximum caseinolytic activity. Furthermore, low lipolytic and amylolytic capacities were detected. The enzymatic potential evaluated with API ZYM system showed that all strains exhibited high Leucine arylamidase, Valine arylamidase and β-Galactosidase activities. Selected LAB were also tested for their antimicrobial activity against Listeria monocytogenes ATCC 7644 using agar well diffusion technique. All extracts of isolates were found to be fully inactivated by proteolytic enzymes, heat stable up to 100°C for 20 min and displayed inhibitory activity at pH from 3.0 to 10.0. Lactic acid bacteria isolated in this study play complex role in the traditional fermentation milk by their functional properties related to a specific enzyme spectrum, acidifying capacity, antimicrobial activities and probiotic properties.

Research Article, Jul 2014

Abstract- This study was carried out to isolate and identify bacterial flora from German cockroac... more Abstract- This study was carried out to isolate and identify bacterial flora from German cockroaches (Blattella germanica) collected from dwellings and health facilities in Tebessa city. A total of 187 bacteria were isolated from 46 cockroachs pecimens. The most common and abundant bacteria species belonged to Enterobacteria group (54.54%), while pathogens like Staphylococcus aureus as well as
Pseudomonas aeruginosa w isolated with a rate of 12.83 % and 4.81 %, respectively. The results indicated that B. germanica is a possible reservoir and carriers of bacterial pathogens via their bodies and thus may spread multiple drug resistance species.

Research Article, Dec 2013

The study was carried out in Tebessa (Northeast Algeria) to investigate antimicrobial susceptibil... more The study was carried out in Tebessa (Northeast Algeria) to investigate antimicrobial susceptibility of Salmonella isolated from poultry product and human patients. Antibiotic resistance profiles were detected against 25 selected antimicrobial agents using micro dilution method (MICs). Seventy-six Salmonella strains were selected and serotyped which Salmonella Enteritidis serovar was the most prevalent serotype. Over all, High level of resistance were noted with quinolones (nalidixic acid), non-wild types with fluoroquinolones (norofloxacin, ofloxacin, ciprofloxacin) and variable scaling values within colistin. Foodborne strains showed some trends to shift toward non-wild types with some beta-lactams and sulfamethoxasole/trimethoprim. Moreover, human serovars showed heterogeneity in susceptibility patterns indicating wide spread multi-drug resistance with quinolones, β-lactams (aminopenicillin, cefalosporin), aminoglycosides, tetracycline, and chloramphenicol. As a result, the relatively high resistance among the Salmonella lying in both human and poultry products could pose therapeutic and public health problems as potential vehicles of resistant Salmonella.