Bulletin of University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca. Veterinary Medicine, 2013
The misuses and uncontrolled veterinary drugs in animals food production can have harmful effects... more The misuses and uncontrolled veterinary drugs in animals food production can have harmful effects on consumers health and dairy industry. The presence of antibiotic residues in milk can cause partial or total inhibition of the growth of lactic acid bacteria, which can induce technological flaws on the cheese production. The aim of this study is to detect antibiotic residues in raw milk produced in Freha area (Tizi-Ouzou) in Algeria. A total of 171 milk samples were collected from 14 dairy farms and examined. The first screening of the samples was carried out by acidification test using Bacillus stearothermophillus (variety calidolactis ATCC 10149), followed by a confirmation test agar with spores of B. stearothermophillus, B. subtilis and B. megaterium. Our results showed a strong presence of antibiotic residues in raw milk, with 80 positive samples (46.78%). Most of them contained penicillin and/or tetracycline (88.75%), followed by macrolide and/or aminoglycoside (12.5%). In contr...
Aims : The aim of this study was to characterize S. aureus isolates of food origin (dairy and mea... more Aims : The aim of this study was to characterize S. aureus isolates of food origin (dairy and meat products, pastries, and sandwiches) determining the carriage in enterotoxin genes and the antimicrobial resistance pheno/genotypes. Methods and results : A total of 300 food samples were collected and analyzed for the detection of S. aureus. The presence of enterotoxin genes was investigated by multiplex-PCRs. Resistance of isolates to eleven antimicrobials was determined using disc diffusion method and molecular characterization of methicillin-resistant S. aureus was carried out by spa-typing and MLST. Overall, 51 out of 300 samples (17%) were contaminated with S. aureus, and 104 isolates were recovered. Sixty-five of these isolates (62.5%) harbored one or more genes encoding for staphylococcal enterotoxins, being seg and sei the most observed genes. The highest resistance profile was ascribed to penicillin G (95.19%). Five isolates were methicillin-resistant (MRSA) harbouring the mecA gene. All MRSA isolates belonged to the sequence-type ST5 and to two different spa-types (t450 and t688); the MRSA-t450 isolate carried the scn gene (specific marker of the immune evasion cluster system), but the four MRSA-t688 isolates were scn-negative. The MRSA isolates carried enterotoxin genes but were negative for the genes of the Panton Valentine leukocidine (lukF/S-PV).
In Algeria, many salt lakes are to be found spread from southern Tunisia up to the Atlas Mountain... more In Algeria, many salt lakes are to be found spread from southern Tunisia up to the Atlas Mountains in northern Algeria. Oum Eraneb and Ain El beida sebkhas (salt lakes), are located in the Algerian Sahara. The aim of this study was to explore the diversity of the halobacteria in this type of habitats. The physicochemical properties of these shallow saline environments were examined and compared with other hypersaline and marine ecosystems. Both sites were relatively alkaline with a pH around 8.57- 8.74 and rich in salt at 13% and 16% (w/v) salinity for Oum Eraneb and Ain El beida, respectively, with dominant ions of sodium and chloride. The microbial approach revealed the presence of two halophilic archaea, strains JCM13561 and A33T in both explored sebkhas. Growth occurred between 10 and 25% (w/v) NaCl and the isolates grow optimally at 20% (w/v) NaCl. The pH range for growth was 6 to 9.5 with an optimum at pH 7.5 for the first strain and 7 to 9.5 with an optimum pH at 8.5-9 for th...
International Journal of Biological Macromolecules, 2019
This study was devoted to polysaccharides extraction (Chitin and Chitosan) from Penicillium camem... more This study was devoted to polysaccharides extraction (Chitin and Chitosan) from Penicillium camembertii cell wall. A culture on solid medium was adopted under carefully selected conditions, appropriate to mycelium growth: duration 6 days, medium YPGA and pH 5. The temperature was adjusted (20°C to 28°C) in order to study the effect of temperature on Chitin/Chitosan production. Biomass decreased with increasing temperatures: 13 g/L at 20°C and 11.6 g/L at 28°C. For all tested temperatures, the yields of insoluble alkaline fractions (AIM) were almost identical (200 mg/g). The solubility of fractions in 2% acetic acid allowed obtaining two fractions: an insoluble fraction (AcIM) with 18% of maximum yield and soluble fraction (AcSM) with 1% yield. The SEM micrographs of AcIM fractions were similar to AIM fractions. These showed a compact structure different from commercial Chitin. The presence of Chitin in P. Camembertii cultured in YPGA medium was also confirmed by ATR spectroscopy.
In the present study, the aerial parts of the Laperrine olive (Olea europaea subsp. Laperrinei) a... more In the present study, the aerial parts of the Laperrine olive (Olea europaea subsp. Laperrinei) are subjected to acid extraction and the chemical composition of the extracts is determined by HPLC-DAD. The main compounds found in all of extracts are: hydroxytyrosol (30.45%), tyrosol (0.69%), oleuropein (32.76%), ferrulic acid (17.77%), quercetin (31.57%) and hesperetin (6.90%).The extracts obtained from the leafy stems of Laperrine olive tree are tested on the moth Ephestia kuehniella flour. Their administration by inhalation of newly exuviated chrysalises extends the duration of nymphalid development and disturbs the exuviated adults reproduction, by reducing the period in which the eggs are being laid. Thus, compared to the control insects, the number of eggs laid by treated females is significantly reduced after the treatment by extracts. Besides, the administration of different extracts of adult butterflies has a premature mortality effect.
International Journal of Minor Fruits, Medicinal and Aromatic Plants, 2021
Medicinal plants are an inexhaustible source of secondary metabolites, namely polyphenols includi... more Medicinal plants are an inexhaustible source of secondary metabolites, namely polyphenols including flavonoids, alkaloids and terpenoids, which generate various biological activities. Keeping this in mind, we were interested in a spontaneous plant Peganum harmala L. to demonstrate the antimitotic and genotoxic effect of the alkaloid and flavonoid fractions (aqueous and butanolic) of the leaves of this species on root meristematic cells of Allium cepa L. Mitotic indices, phase indices, aberration indices as well as cytotoxicity limit values were calculated for our different samples and controls, namely the negative (distilled water) and positive controls (colchicine 1mg/ml and quercetin 1mg/ml). The results indicate a mitodepressant and sublethal effect, observed with the alkaloid and flavonoid fractions of the leaves of Peganum harmala L. Exposure of meristematic cells to the samples resulted in an antimitotic and genotoxic effect translated into a large number of chromosomal, nucle...
Background Despite the fact that the implication of human papillomavirus (HPV) in the carcinogene... more Background Despite the fact that the implication of human papillomavirus (HPV) in the carcinogenesis and prognosis of cervical cancer is well established, the impact of a co-infection with high risk HPV (HR-HPV) and Epstein-Barr virus (EBV) is still not fully understood. Methods Fifty eight randomly selected cases of squamous cell carcinomas (SCC) of the uterine cervix, 14 normal cervices specimens, 21 CIN-2/3 and 16 CIN-1 cases were examined for EBV and HPV infections. Detection of HR-HPV specific sequences was carried out by PCR amplification using consensus primers of Manos and by Digene Hybrid Capture. The presence of EBV was revealed by amplifying a 660 bp specific EBV sequence of BALF1. mRNA expression of LMP-1 in one hand and protein levels of BARF-1, LMP-1 and EBNA-1 in the other hand were assessed by RT-PCR and immunoblotting and/or immunohischemistry respectively. Results HR-HPV infection was found in patients with SCC (88%), low-grade (75%) and high grade (95%) lesions co...
Conservation at low temperatures prolongs the shelf life of food products, but some- times it pro... more Conservation at low temperatures prolongs the shelf life of food products, but some- times it promotes the growth of psychrophilic microorganisms. In addition, use of syn- thetic conservatives is restricted Olmedo, Nepote & Grosso, 2013); hence the interest to explore alternative antimicrobial sources. Most essential oils have been classified as gen- erally recognized as safe (Burt, 2004), and their antimicrobial activity is well demonstrated in vitro and in food model. In this work, we have determined the antibacterial activity of essential oils (EO) from Thymus fontaneseii, alone or in combination with and Scirpus ho- loschoenus phenolic extract (SPE), against Pseudomonas aeruginosa ATCC 27853, which is an opportunist and food spoilage bacteria. The EO was obtained with hydrodistillation and phenolic extract with microwave assisted extraction. The diameters of the zones of inhibi- tion at 7°C were 43.00 ± 1 mm, 17.7± 0.57 mm and 63 ± 2 mm with EOd (12.5%), SPE (70mg /mL) and their...
Nettle (Urtica dioica L), as a plant rich in biologically active compounds, is one of the most im... more Nettle (Urtica dioica L), as a plant rich in biologically active compounds, is one of the most important plants used in herbal medicine. Studies have shown that this plant has antioxidant, antiplatelet, hypoglycemic and hypocholesterolemia effects. In this study, we characterized three Alternaria endophytic fungi isolated from their host U. dioica. We hypothesized that these endophytic fungi can produce new bioactive metabolites, which may possess the bioactive property with potential application in the medical and pharmaceutical industries. The antibacterial activity was evaluated against reference and isolated strains, including Methicillin-Resistant Staphylococcus aureus. A wide range of antimicrobial activities similar to those measured in nettle leaves was detected especially for Alternaria sorghi. Furthermore, the highest antioxidant activity detected with DPPH free radical scavenging was measured for A. sorghi and nettle leaves ethyl acetate extracts. In addition, whereas cat...
The current study aims to the spatiotemporal assessment and monitoring of hydrocarbons contaminat... more The current study aims to the spatiotemporal assessment and monitoring of hydrocarbons contamination in water and sediments of Skikda bay (Algeria), as a result of the presence of industrial wastew...
Many plant species produce phenolic compounds in their various organs and their use in crop prote... more Many plant species produce phenolic compounds in their various organs and their use in crop protection. These plant secondary metabolites may serve as toxins against the insect pests. The objective of this study was to evaluate in vitro the bio-insecticidal effect of an aqueous extract of wild Olive leaves on Psylla larvae (Euphyllura olivina), a primary pest of the cultivated Olive tree (Olea europaea L. subsp sativa). Two concentrations of 0.05g/ml and 0.1g/ml leaves grinding powder in distilled water were sprayed on branches infested with Psylla larvae. The obtained results revealed a very significant mortality rate of the larvae 24 hours after spraying. The chemical composition of Oleaster leaves aqueous extracts is determined by HPLC-DAD. The results show in majority the presence of phenolic compounds represented by oleuropein and its metabolite hydroxytyrosol. The phenolic compounds of the crude extract were at the origin of this mortality. The Analysis of Variance revealed highly significant results both between the sampled trees and between the tested concentrations. The Principal Component Analysis (PCA) revealed a close relation between the physiological state of the studied trees and the degree of their infestation by the phytophagus. Taking into account, the physical and chemical characteristics of the sampled soils, data analysis showed that trees growing on nitrogen-rich soils were more infested than those growing on soils rich in organic carbon (Corg) and phosphorus (Porg).
The misuses and uncontrolled veterinary drugs in animals food production can have harmful effects... more The misuses and uncontrolled veterinary drugs in animals food production can have harmful effects on consumers health and dairy industry. The presence of antibiotic residues in milk can cause partial or total inhibition of the growth of lactic acid bacteria, which can induce technological flaws on the cheese production. The aim of this study is to detect antibiotic residues in raw milk produced in Freha area (Tizi-Ouzou) in Algeria. A total of 171 milk samples were collected from 14 dairy farms and examined. The first screening of the samples was carried out by acidification test using Bacillus stearothermophillus (variety calidolactis ATCC 10149), followed by a confirmation test agar with spores of B. stearothermophillus, B. subtilis and B. megaterium. Our results showed a strong presence of antibiotic residues in raw milk, with 80 positive samples (46.78%). Most of them contained penicillin and/or tetracycline (88.75%), followed by macrolide and/or aminoglycoside (12.5%). In contr...
Epstein-Barr virus is associated with gastric carcinoma. There has been no study about the freque... more Epstein-Barr virus is associated with gastric carcinoma. There has been no study about the frequency of Epstein Barr virus associated gastric carcinoma (EBVaGC) in Algeria an endemic area of nasopharyngeal carcinoma. The objective of this study is to investigate the prevalence of EBVaGC among Algerian patients and to define EBV latency patterns in this tumor.The expression of latent membrane protein-1 (LMP-1) was evaluated in EBV positive cases with specific monoclonal antibodies using immunofluorescence and immunohistochemistry techniques.97 cases selected of gastric carcinoma were examined for EBV infection using fluorescence in situ hybridization assay to detect EBV-encoded small RNAs (EBER-1 and EBER-2). Combined immunofluorescence and fluorescence in situ hybridization was carried out in 15 gastric carcinoma cases to confirm the presence of EBERs and LMP-1 simultaneously. We have shown that 22 out of 97 cases (22.7%) expressed EBV. EBERs were present within the malignant epithe...
Giardia intestinalis is one of the most common causes of parasite-induced diarrhea, abdominal pai... more Giardia intestinalis is one of the most common causes of parasite-induced diarrhea, abdominal pain, flatulence, and malabsorption. Yet, data on the epidemiology of G. intestinalis infections in North Africa are limited. The purpose of this study was to carry out a retrospective survey on the level of intestinal parasitism with a particular emphasis on G. intestinalis in children and adults in Algiers, Algeria. A total of 2,054 individuals from outpatient clinics or hospitalized at Beni-Messous University Hospital of Algiers undergoing stool microscopy for ova and parasites were included. The overall parasite infection rate was 28%. In the 567 parasite-positive samples, Blastocystis was found most frequently (57.3%), followed in frequency by Endolimax nana (41.0%), Entamoeba histolytica/dispar (19.6%), G. intestinalis (17.1%), Entamoeba coli (13.9%), Chilomastix mesnili (1.0%), Iodamoeba bütschlii (0.7%), Entamoeba hartmanni (0.5%), and Cryptosporidium spp. (0.2%). Intestinal parasit...
Antibiotics are efficiency substances for the treatment and improvement of animal production yiel... more Antibiotics are efficiency substances for the treatment and improvement of animal production yields. However, their irrational and non-moderate using can cause serious problems for the consumer and the manufacturer. The aim of this study is to check their presence in the poultry meat by conventional microbiological methods (four boxes) recommended and approved by French Agency of Food Safety (AFSSA). For this purpose, 145 poultry meat samples were taken from various breeding farms and tested by Plates Agar diffusion at different pH (6, 7.2 and 8), seeded by two references strains: Bacillus subtilis (BGA spores) and Micrococcus luteus (ATCC 9341). The results revealed that 124 out of 145 poultry meat samples were positive to antibiotic residues with the percentage of 85.51%. However, most of them contained 75.81% of I²-lactams and/or Tetracyclines against 44.35% for Macrolides and/or I²-Lactams and 36.29% for Sulfonamides. Conversely, 13.71% of samples were positive to aminoglycoside...
Gastric cancer is one of the most common cancers in the world with one million new cases each yea... more Gastric cancer is one of the most common cancers in the world with one million new cases each year. It remains the second leading cause of death by cancer for both sexes. In Algeria, it represents 5% of all cancers listed and it comes in the fifth position with 1430 new cases each year. Gastric cancer was associated with Epstein-Barr virus (EBV) with an incidence of 10 to 18%. The LMP-1 protein is considered as the major EBV oncogene. Thanks to its signaling, LMP1 presents immortalization and transformation properties, able of inhibiting cell differentiation. The most promising approach to reduce mortality from gastric cancer is the early diagnosis by identifying specific and sensitive biomarkers. It is in this context that we first realized electrophoresis on cellulose acetate plates of the sera of patients with gastric cancer. The proteinogram obtained are, in general, very similar and they have a uniform appearance like paths known to be normal. Some of them have hypo-proteinemia...
Background: Conventional food additives were associated with potential harm. Palm seeds are an in... more Background: Conventional food additives were associated with potential harm. Palm seeds are an interesting source of high-added value bioactive compounds, regarding their potential use in food industries. Aim: Date seeds extract (DSE) of Algerian Phoenix dactyliefra L. was studied for its phytochemical, antioxidant, and antibacterial activity and to identify its potential uses in foods. Material and methods: A total soluble solid of DSE (°Brix) was determined by refractometry. The total phenolic contents (TPCs) were determined according to the Folin-Cioclateu method and the total flavonoid and flavonols were also estimated with the colorimetric method. The DPPH method was used to determine the antioxidant activity of DSE. The IC50 values were also calculated and the antioxidant activity index (AAI) was determined. The agar well diffusion method was employed for the antibacterial activity of the aqueous DSE against various pathogens. Results: Moisture, ash, and fat contents (%) deter...
Bulletin of University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca. Veterinary Medicine, 2013
The misuses and uncontrolled veterinary drugs in animals food production can have harmful effects... more The misuses and uncontrolled veterinary drugs in animals food production can have harmful effects on consumers health and dairy industry. The presence of antibiotic residues in milk can cause partial or total inhibition of the growth of lactic acid bacteria, which can induce technological flaws on the cheese production. The aim of this study is to detect antibiotic residues in raw milk produced in Freha area (Tizi-Ouzou) in Algeria. A total of 171 milk samples were collected from 14 dairy farms and examined. The first screening of the samples was carried out by acidification test using Bacillus stearothermophillus (variety calidolactis ATCC 10149), followed by a confirmation test agar with spores of B. stearothermophillus, B. subtilis and B. megaterium. Our results showed a strong presence of antibiotic residues in raw milk, with 80 positive samples (46.78%). Most of them contained penicillin and/or tetracycline (88.75%), followed by macrolide and/or aminoglycoside (12.5%). In contr...
Aims : The aim of this study was to characterize S. aureus isolates of food origin (dairy and mea... more Aims : The aim of this study was to characterize S. aureus isolates of food origin (dairy and meat products, pastries, and sandwiches) determining the carriage in enterotoxin genes and the antimicrobial resistance pheno/genotypes. Methods and results : A total of 300 food samples were collected and analyzed for the detection of S. aureus. The presence of enterotoxin genes was investigated by multiplex-PCRs. Resistance of isolates to eleven antimicrobials was determined using disc diffusion method and molecular characterization of methicillin-resistant S. aureus was carried out by spa-typing and MLST. Overall, 51 out of 300 samples (17%) were contaminated with S. aureus, and 104 isolates were recovered. Sixty-five of these isolates (62.5%) harbored one or more genes encoding for staphylococcal enterotoxins, being seg and sei the most observed genes. The highest resistance profile was ascribed to penicillin G (95.19%). Five isolates were methicillin-resistant (MRSA) harbouring the mecA gene. All MRSA isolates belonged to the sequence-type ST5 and to two different spa-types (t450 and t688); the MRSA-t450 isolate carried the scn gene (specific marker of the immune evasion cluster system), but the four MRSA-t688 isolates were scn-negative. The MRSA isolates carried enterotoxin genes but were negative for the genes of the Panton Valentine leukocidine (lukF/S-PV).
In Algeria, many salt lakes are to be found spread from southern Tunisia up to the Atlas Mountain... more In Algeria, many salt lakes are to be found spread from southern Tunisia up to the Atlas Mountains in northern Algeria. Oum Eraneb and Ain El beida sebkhas (salt lakes), are located in the Algerian Sahara. The aim of this study was to explore the diversity of the halobacteria in this type of habitats. The physicochemical properties of these shallow saline environments were examined and compared with other hypersaline and marine ecosystems. Both sites were relatively alkaline with a pH around 8.57- 8.74 and rich in salt at 13% and 16% (w/v) salinity for Oum Eraneb and Ain El beida, respectively, with dominant ions of sodium and chloride. The microbial approach revealed the presence of two halophilic archaea, strains JCM13561 and A33T in both explored sebkhas. Growth occurred between 10 and 25% (w/v) NaCl and the isolates grow optimally at 20% (w/v) NaCl. The pH range for growth was 6 to 9.5 with an optimum at pH 7.5 for the first strain and 7 to 9.5 with an optimum pH at 8.5-9 for th...
International Journal of Biological Macromolecules, 2019
This study was devoted to polysaccharides extraction (Chitin and Chitosan) from Penicillium camem... more This study was devoted to polysaccharides extraction (Chitin and Chitosan) from Penicillium camembertii cell wall. A culture on solid medium was adopted under carefully selected conditions, appropriate to mycelium growth: duration 6 days, medium YPGA and pH 5. The temperature was adjusted (20°C to 28°C) in order to study the effect of temperature on Chitin/Chitosan production. Biomass decreased with increasing temperatures: 13 g/L at 20°C and 11.6 g/L at 28°C. For all tested temperatures, the yields of insoluble alkaline fractions (AIM) were almost identical (200 mg/g). The solubility of fractions in 2% acetic acid allowed obtaining two fractions: an insoluble fraction (AcIM) with 18% of maximum yield and soluble fraction (AcSM) with 1% yield. The SEM micrographs of AcIM fractions were similar to AIM fractions. These showed a compact structure different from commercial Chitin. The presence of Chitin in P. Camembertii cultured in YPGA medium was also confirmed by ATR spectroscopy.
In the present study, the aerial parts of the Laperrine olive (Olea europaea subsp. Laperrinei) a... more In the present study, the aerial parts of the Laperrine olive (Olea europaea subsp. Laperrinei) are subjected to acid extraction and the chemical composition of the extracts is determined by HPLC-DAD. The main compounds found in all of extracts are: hydroxytyrosol (30.45%), tyrosol (0.69%), oleuropein (32.76%), ferrulic acid (17.77%), quercetin (31.57%) and hesperetin (6.90%).The extracts obtained from the leafy stems of Laperrine olive tree are tested on the moth Ephestia kuehniella flour. Their administration by inhalation of newly exuviated chrysalises extends the duration of nymphalid development and disturbs the exuviated adults reproduction, by reducing the period in which the eggs are being laid. Thus, compared to the control insects, the number of eggs laid by treated females is significantly reduced after the treatment by extracts. Besides, the administration of different extracts of adult butterflies has a premature mortality effect.
International Journal of Minor Fruits, Medicinal and Aromatic Plants, 2021
Medicinal plants are an inexhaustible source of secondary metabolites, namely polyphenols includi... more Medicinal plants are an inexhaustible source of secondary metabolites, namely polyphenols including flavonoids, alkaloids and terpenoids, which generate various biological activities. Keeping this in mind, we were interested in a spontaneous plant Peganum harmala L. to demonstrate the antimitotic and genotoxic effect of the alkaloid and flavonoid fractions (aqueous and butanolic) of the leaves of this species on root meristematic cells of Allium cepa L. Mitotic indices, phase indices, aberration indices as well as cytotoxicity limit values were calculated for our different samples and controls, namely the negative (distilled water) and positive controls (colchicine 1mg/ml and quercetin 1mg/ml). The results indicate a mitodepressant and sublethal effect, observed with the alkaloid and flavonoid fractions of the leaves of Peganum harmala L. Exposure of meristematic cells to the samples resulted in an antimitotic and genotoxic effect translated into a large number of chromosomal, nucle...
Background Despite the fact that the implication of human papillomavirus (HPV) in the carcinogene... more Background Despite the fact that the implication of human papillomavirus (HPV) in the carcinogenesis and prognosis of cervical cancer is well established, the impact of a co-infection with high risk HPV (HR-HPV) and Epstein-Barr virus (EBV) is still not fully understood. Methods Fifty eight randomly selected cases of squamous cell carcinomas (SCC) of the uterine cervix, 14 normal cervices specimens, 21 CIN-2/3 and 16 CIN-1 cases were examined for EBV and HPV infections. Detection of HR-HPV specific sequences was carried out by PCR amplification using consensus primers of Manos and by Digene Hybrid Capture. The presence of EBV was revealed by amplifying a 660 bp specific EBV sequence of BALF1. mRNA expression of LMP-1 in one hand and protein levels of BARF-1, LMP-1 and EBNA-1 in the other hand were assessed by RT-PCR and immunoblotting and/or immunohischemistry respectively. Results HR-HPV infection was found in patients with SCC (88%), low-grade (75%) and high grade (95%) lesions co...
Conservation at low temperatures prolongs the shelf life of food products, but some- times it pro... more Conservation at low temperatures prolongs the shelf life of food products, but some- times it promotes the growth of psychrophilic microorganisms. In addition, use of syn- thetic conservatives is restricted Olmedo, Nepote & Grosso, 2013); hence the interest to explore alternative antimicrobial sources. Most essential oils have been classified as gen- erally recognized as safe (Burt, 2004), and their antimicrobial activity is well demonstrated in vitro and in food model. In this work, we have determined the antibacterial activity of essential oils (EO) from Thymus fontaneseii, alone or in combination with and Scirpus ho- loschoenus phenolic extract (SPE), against Pseudomonas aeruginosa ATCC 27853, which is an opportunist and food spoilage bacteria. The EO was obtained with hydrodistillation and phenolic extract with microwave assisted extraction. The diameters of the zones of inhibi- tion at 7°C were 43.00 ± 1 mm, 17.7± 0.57 mm and 63 ± 2 mm with EOd (12.5%), SPE (70mg /mL) and their...
Nettle (Urtica dioica L), as a plant rich in biologically active compounds, is one of the most im... more Nettle (Urtica dioica L), as a plant rich in biologically active compounds, is one of the most important plants used in herbal medicine. Studies have shown that this plant has antioxidant, antiplatelet, hypoglycemic and hypocholesterolemia effects. In this study, we characterized three Alternaria endophytic fungi isolated from their host U. dioica. We hypothesized that these endophytic fungi can produce new bioactive metabolites, which may possess the bioactive property with potential application in the medical and pharmaceutical industries. The antibacterial activity was evaluated against reference and isolated strains, including Methicillin-Resistant Staphylococcus aureus. A wide range of antimicrobial activities similar to those measured in nettle leaves was detected especially for Alternaria sorghi. Furthermore, the highest antioxidant activity detected with DPPH free radical scavenging was measured for A. sorghi and nettle leaves ethyl acetate extracts. In addition, whereas cat...
The current study aims to the spatiotemporal assessment and monitoring of hydrocarbons contaminat... more The current study aims to the spatiotemporal assessment and monitoring of hydrocarbons contamination in water and sediments of Skikda bay (Algeria), as a result of the presence of industrial wastew...
Many plant species produce phenolic compounds in their various organs and their use in crop prote... more Many plant species produce phenolic compounds in their various organs and their use in crop protection. These plant secondary metabolites may serve as toxins against the insect pests. The objective of this study was to evaluate in vitro the bio-insecticidal effect of an aqueous extract of wild Olive leaves on Psylla larvae (Euphyllura olivina), a primary pest of the cultivated Olive tree (Olea europaea L. subsp sativa). Two concentrations of 0.05g/ml and 0.1g/ml leaves grinding powder in distilled water were sprayed on branches infested with Psylla larvae. The obtained results revealed a very significant mortality rate of the larvae 24 hours after spraying. The chemical composition of Oleaster leaves aqueous extracts is determined by HPLC-DAD. The results show in majority the presence of phenolic compounds represented by oleuropein and its metabolite hydroxytyrosol. The phenolic compounds of the crude extract were at the origin of this mortality. The Analysis of Variance revealed highly significant results both between the sampled trees and between the tested concentrations. The Principal Component Analysis (PCA) revealed a close relation between the physiological state of the studied trees and the degree of their infestation by the phytophagus. Taking into account, the physical and chemical characteristics of the sampled soils, data analysis showed that trees growing on nitrogen-rich soils were more infested than those growing on soils rich in organic carbon (Corg) and phosphorus (Porg).
The misuses and uncontrolled veterinary drugs in animals food production can have harmful effects... more The misuses and uncontrolled veterinary drugs in animals food production can have harmful effects on consumers health and dairy industry. The presence of antibiotic residues in milk can cause partial or total inhibition of the growth of lactic acid bacteria, which can induce technological flaws on the cheese production. The aim of this study is to detect antibiotic residues in raw milk produced in Freha area (Tizi-Ouzou) in Algeria. A total of 171 milk samples were collected from 14 dairy farms and examined. The first screening of the samples was carried out by acidification test using Bacillus stearothermophillus (variety calidolactis ATCC 10149), followed by a confirmation test agar with spores of B. stearothermophillus, B. subtilis and B. megaterium. Our results showed a strong presence of antibiotic residues in raw milk, with 80 positive samples (46.78%). Most of them contained penicillin and/or tetracycline (88.75%), followed by macrolide and/or aminoglycoside (12.5%). In contr...
Epstein-Barr virus is associated with gastric carcinoma. There has been no study about the freque... more Epstein-Barr virus is associated with gastric carcinoma. There has been no study about the frequency of Epstein Barr virus associated gastric carcinoma (EBVaGC) in Algeria an endemic area of nasopharyngeal carcinoma. The objective of this study is to investigate the prevalence of EBVaGC among Algerian patients and to define EBV latency patterns in this tumor.The expression of latent membrane protein-1 (LMP-1) was evaluated in EBV positive cases with specific monoclonal antibodies using immunofluorescence and immunohistochemistry techniques.97 cases selected of gastric carcinoma were examined for EBV infection using fluorescence in situ hybridization assay to detect EBV-encoded small RNAs (EBER-1 and EBER-2). Combined immunofluorescence and fluorescence in situ hybridization was carried out in 15 gastric carcinoma cases to confirm the presence of EBERs and LMP-1 simultaneously. We have shown that 22 out of 97 cases (22.7%) expressed EBV. EBERs were present within the malignant epithe...
Giardia intestinalis is one of the most common causes of parasite-induced diarrhea, abdominal pai... more Giardia intestinalis is one of the most common causes of parasite-induced diarrhea, abdominal pain, flatulence, and malabsorption. Yet, data on the epidemiology of G. intestinalis infections in North Africa are limited. The purpose of this study was to carry out a retrospective survey on the level of intestinal parasitism with a particular emphasis on G. intestinalis in children and adults in Algiers, Algeria. A total of 2,054 individuals from outpatient clinics or hospitalized at Beni-Messous University Hospital of Algiers undergoing stool microscopy for ova and parasites were included. The overall parasite infection rate was 28%. In the 567 parasite-positive samples, Blastocystis was found most frequently (57.3%), followed in frequency by Endolimax nana (41.0%), Entamoeba histolytica/dispar (19.6%), G. intestinalis (17.1%), Entamoeba coli (13.9%), Chilomastix mesnili (1.0%), Iodamoeba bütschlii (0.7%), Entamoeba hartmanni (0.5%), and Cryptosporidium spp. (0.2%). Intestinal parasit...
Antibiotics are efficiency substances for the treatment and improvement of animal production yiel... more Antibiotics are efficiency substances for the treatment and improvement of animal production yields. However, their irrational and non-moderate using can cause serious problems for the consumer and the manufacturer. The aim of this study is to check their presence in the poultry meat by conventional microbiological methods (four boxes) recommended and approved by French Agency of Food Safety (AFSSA). For this purpose, 145 poultry meat samples were taken from various breeding farms and tested by Plates Agar diffusion at different pH (6, 7.2 and 8), seeded by two references strains: Bacillus subtilis (BGA spores) and Micrococcus luteus (ATCC 9341). The results revealed that 124 out of 145 poultry meat samples were positive to antibiotic residues with the percentage of 85.51%. However, most of them contained 75.81% of I²-lactams and/or Tetracyclines against 44.35% for Macrolides and/or I²-Lactams and 36.29% for Sulfonamides. Conversely, 13.71% of samples were positive to aminoglycoside...
Gastric cancer is one of the most common cancers in the world with one million new cases each yea... more Gastric cancer is one of the most common cancers in the world with one million new cases each year. It remains the second leading cause of death by cancer for both sexes. In Algeria, it represents 5% of all cancers listed and it comes in the fifth position with 1430 new cases each year. Gastric cancer was associated with Epstein-Barr virus (EBV) with an incidence of 10 to 18%. The LMP-1 protein is considered as the major EBV oncogene. Thanks to its signaling, LMP1 presents immortalization and transformation properties, able of inhibiting cell differentiation. The most promising approach to reduce mortality from gastric cancer is the early diagnosis by identifying specific and sensitive biomarkers. It is in this context that we first realized electrophoresis on cellulose acetate plates of the sera of patients with gastric cancer. The proteinogram obtained are, in general, very similar and they have a uniform appearance like paths known to be normal. Some of them have hypo-proteinemia...
Background: Conventional food additives were associated with potential harm. Palm seeds are an in... more Background: Conventional food additives were associated with potential harm. Palm seeds are an interesting source of high-added value bioactive compounds, regarding their potential use in food industries. Aim: Date seeds extract (DSE) of Algerian Phoenix dactyliefra L. was studied for its phytochemical, antioxidant, and antibacterial activity and to identify its potential uses in foods. Material and methods: A total soluble solid of DSE (°Brix) was determined by refractometry. The total phenolic contents (TPCs) were determined according to the Folin-Cioclateu method and the total flavonoid and flavonols were also estimated with the colorimetric method. The DPPH method was used to determine the antioxidant activity of DSE. The IC50 values were also calculated and the antioxidant activity index (AAI) was determined. The agar well diffusion method was employed for the antibacterial activity of the aqueous DSE against various pathogens. Results: Moisture, ash, and fat contents (%) deter...
Uploads
Papers by Karim Houali