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Concern about the discharge of untreated industrial wastewater as a threat to the ecosystem is seriously increasing every day. Part of these discharges are generated by the agri-food industries, which must consider purification for successful remediation of ecosystems. Effluents from dairy industries are among the agri-food wastes richest in organic matter. It constitutes a major source of pollution due to its richness in macroelements and microbial pollutants. This study focused on the treatment of raw dairy effluents (RDE) from a dairy unit located in Bechar (Southwestern Algeria) using two processes: the first, a biological process in a laboratory-scale batch culture through three bacterial strains, namely Bacillus subtilis, Pseudomonas aeruginosa, and E. coli, and the second, a chemical treatment by adding different concentrations of coagulants [Al2(SO4)3; FeCl3]. Pollution indicator parameters, namely BOD5, COD, and total nitrogen content (TKN) were monitored and compared with the control sample (RDE). The results obtained for the analyzed pollution parameters of dairy effluents (COD: 653mgO2/L; BOD5: 554,5mgO2/L; TKN: 57,2mg/L; and NO3 -: 80mg/L) exceed the thresholds set by national regulations and must be adjusted to ensure compliance with Algerian standards. The results of the biological treatment showed high purification efficiency compared to chemical treatment with an abatement rate of 84,84% for COD; 95,06% for BOD5; 87,76% for total nitrogen; and 67,62% for nitrate, and removal of bacterial indicators of pollution by 48-50% for fecal coliforms; and 34-40% for fecal streptococci at the outlet of the batch culture system, attributed to B. subtilis and P. aeruginosa strains making post-treatment dairy effluents more compliant with national discharge standards than E. coli by reducing pollution indicator parameters. While chemical treatment with coagulants were less favorable with relatively high COD and BOD values. These results confirm the advantage of biological processes, which are simple, economical, and respectful of the environment. Thus, the purified effluent can be reused on-site in the production process, namely cooling, washing, and even irrigation. [ABSTRACT FROM AUTHOR]

This study aims to assess the physicochemical, biochemical, and microbiological quality of dried and salted camel meat, a traditional product of the inhabitants of southern Algeria. A total of 8 test samples of dried and salted camel meat from three regions in southwestern Algeria, against two other control samples (i.e 10 samples in total), were subjected to a series of analyses for some physicochemical and biochemical parameters (pH, sodium chloride content, total solid content, moisture content, ash content, waterholding capacity, protein content, fat content, total sugar content, and detection of antibiotic residues), and microbiological parameters (TAMF, fungal flora, total and fecal coliforms, fungal flora, SRC, Bacillus spp, and pathogenic bacteria such as coagulase-positive staphylococci, Listeria monocytogenes, Pseudomonas spp, and Salmonella spp), following official and reference methods. The physicochemical results showed that the pH and titratable acidity of the dried and salted camel meat samples were acidic with values ranging from 5,14 to 5,72; and 3g/L to 3,63g/L, respectively. The analyzed samples had sodium chloride content ranging from 0,09g/L to 3,31g/L, (6,46% to 25,34%) moisture content, (3,86% to 38,58%) ash content, (162,5% to 267,7%) water-holding capacity, against (0,15g/L; 0,12g/L); (25,34%; 76,75%); (5,78%; 4,73%); (162,52%; 99,33%) for the control samples, which are laboratory-prepared dried camel meat, and fresh camel meat sold in Bechar city, respectively. However, biochemical parameters showed a protein content ranging from 21,7% to 36%, (4,9% to 23,3%) fat content, and (20mg/L to 76,51mg/L) total sugar content, with no antibiotic residues. The microbiological results showed a TAMF load ranging from 4,02 to 6,46 Log10 CFU/g, and 2,48 to 5,21 Log10 CFU/g for total coliforms, where 33% of the samples were contaminated with fecal coliforms. All samples analyzed were free of pathogenic bacteria, namely coagulase-positive staphylococci, Listeria monocytogenes, Pseudomonas spp, and Salmonella spp. Bacillus cereus was detected in one sample (C), while the isolated CoNS species were identified as follows: S. saprophyticus, and S. epidermidis. From previous studies revealing various recipes for preparing dried and salted meat in the southwestern regions studied, this meat by-product presents very interesting physicochemical, biochemical, and hygienic characteristics at the nutritional level compared to fresh meat, which not only contributes to its preservation but also improves its sensory quality. [ABSTRACT FROM AUTHOR]

Water is the most important element of life. Ensuring its quality and drinkability is the most important challenge worldwide. This study aimed to evaluate the physicochemical and bacteriological quality of 10 water samples from the feed water storage tank of a dairy unit located in Bechar (South-West of Algeria). The obtained results show that the analyzed physicochemical parameters, namely: pH, electrical conductivity, salinity, total dissolved solids, fluoride, sulfate, phosphate, and nitrate contents meet the thresholds set by national regulations. However, all the analyzed water samples had an oxidizable organic matter content (OOM) of 5,6 to 28,8mgO2/L exceeding the standard, with a total suspended solids rate (TSS) ranging from 43,81 to 50,19%. The total hardness results indicate that samples were hard with a TH ranging from 30 to 115°f. The bacteriological analysis showed that 5 and 3 samples out of all the analyzed samples were contaminated with Pseudomonas aeruginosa and sulfite-reducing Clostridia, while the two samples (S9 and S1) were contaminated with total coliforms and fecal coliforms. A rate of 60% of the analyzed samples had a TAMF load ranging from 1,84 to 4,32 Log10 CFU/mL at 30°C. However, all samples were Salmonella spp and Enterococci spp-free. The identification of the isolated bacterial species was as follows: Escherichia coli, Aeromonas hydrophila, Chromobacterium violaceum, Escherichia vulneris, Enterobacter cloacae, and Enterobacter amnigenus. High values of OOM and TSS, as well as 50% of the analyzed water samples contaminated with Pseudomonas aeruginosa considered an opportunistic contaminant in water, makes the quality of the water tank questionable. This is probably due to unsafe storage. As a result, safe storage and handling of water at the point of use is much needed to provide safe, food-grade water on an industrial scale, and therefore prevent the transmission of waterborne diseases. [ABSTRACT FROM AUTHOR]

Lactic acid bacteria (LAB) strains are a natural part of our foods and environment. It has long been recognized to produce antimicrobial substances, used both for fermentation and the bio-preservation of food. Hence the importance of this work which focused on the study of the antagonistic effect of LAB strains isolated from fermented goat milk flavored with Phoenician juniper leaves stored in goatskin churn (Chekoua), against some microbial contaminants. Some technological properties of LAB strains were assessed and the antibacterial effect of lactic acid isolates was done using a spot test on agar. However, the antifungal effect was evaluated through the mycelial radial growth on agar and the biomass on broth culture. Out of seven isolated lactic acid strains, three (3) belong to Lactobacillus spp (Lb) and four (4) others to Streptococcus spp (S). The physiological and technological characteristics were different from one to another. S1, S2, S3, S4, and Lactobacillus plantarum (Lb1) strains have shown interesting technological properties (acidifying power, and proteolytic activity). On the one hand, all the lactic acid isolates were γ-hemolytic, and on the other hand, lactobacilli strains were resistant to a total of (6 to 7) antibiotics out of 12 tested antibiotics, i.e. 50 to 58%, while streptococci strains were susceptible to almost all the tested antibiotics except two antibiotics from the quinolones and sulfonamides class: pefloxacin and co-trimoxazole. The antimicrobial effect results indicate that S1 and S2 strains exhibited an antagonistic effect against the growth of bacterial contaminants, namely Staphylococcus aureus, Serratia ordorifera, and Entrobacter sakazakii isolated from goat milk. Lb1, S1, S2, S3, and S4 strains showed an antifungal effect with an inhibition rate ranging from 50 to 60%; 27.5 to 50% and 59.6 to 80.17% based on spore suspension, mycelial disc, and fungal biomass method, respectively. The antimicrobial effect was probably due to the synthesis of inhibitory substances, which constitutes a perspective for further research on both the characteristics of microflora, their identification as species and bioactive antimicrobial compounds, and the search for new and more effective LAB strains as a starter culture from traditional food products. [ABSTRACT FROM AUTHOR]

As an opportunistic pathogen that lives in wetlands such as water, the presence of Pseudomonas spp in drinking water or that intended for the agrifood industry can pose a risk to consumers. The study aims to search for Pseudomonas spp in the feed water tank of a dairy unit located in Bechar, and then to characterize the virulence factors of the isolates, namely antibiotics resistance, hemolytic power, and biofilm formation. A total of 10 water samples were analyzed to isolate Pseudomonas by the membrane filter technique. The identification of Pseudomonas spp isolates was carried out using standard microbiological methods. The Kirby-Bauer diffusion test-based assessment of antibiotic susceptibility was performed. The bacteriological analysis showed that 7/10 (i.e. 70%) of the water samples were contaminated with Pseudomonas spp. However, bacterial identification confirmed that the isolated strains belonged to the P. aeruginosa species. These strains showed a resistance rate of 100% to cefazolin, ticarcillin-clavulanic acid, ceftazidime, cefotaxime, cephalothin, and cefoxitin, and at a lower rate of resistance, i.e. 86 and 57% for amikacin and tobramycin, respectively, and sensitive to ciprofloxacin, ofloxacin, piperacillin, piperacillin-tazobactam, and gentamicin, which seemed to be the most active molecules. Based on antibiotic resistance results against the aminoglycoside, cephalosporin, and ß-lactam classes, all the P. aeruginosa isolates were classified as multidrug-resistant (MDR). Besides, all the P. aeruginosa isolates show ß-hemolysis and can form biofilms. P. aeruginosa isolates showed a worrying degree of virulence that requires special attention from the dairy unit managers, and appropriate treatment should be conducted to eliminate any risk that could harm consumers. [ABSTRACT FROM AUTHOR]

Today, there is a growing demand for natural antioxidants. The unbalanced production and consumption of reactive oxygen species cause many disorders such as cancer, arteriosclerosis, Alzheimer's disease and aging. For this purpose, the present study was a part of the in vitro evaluation of the antioxidant activity of Quercus robur L. leaves' selective extracts, namely tannins and saponins groups. The antioxidant activity was evaluated by using two techniques: the DPPH radical scavenging activity method and the ferric reducing antioxidant power method. In addition, a kinetic behavior study of the antiradical activity was established. The obtained results show that tannins and saponins extracts have a significant free radical scavenging activity with IC50 values of 0.128 and 0.145 mg mL-1, respectively. Moreover, the kinetic behavior of the scavenging ability of the studied extracts makes it possible to determine the antiradical efficiency, the antiradical power, the percentage of the remaining DPPH free radical, the TIC50 parameter, the half-reaction time and the equilibrium antiradical reaction time. These results showed that the tested extracts provided a significant antioxidant activity. This plant can keep an important value in pharmacy and herbal medicine, and act as natural agents in food applications. [ABSTRACT FROM AUTHOR]

Background: The microbial infections represent a real public health problem with considerable individual and economical consequences. Their surveillance has become, in recent decades, an essential element of any program to control these infections. Aim: In this study, we estimated the prevalence and frequencies of some microbial infections amongst the Bechar's community (Algeria). Methods: The microbiological analyzes of various pathological samples namely : urine and vaginal discharge, pus, nipple discharge, originally sampled from throat, otitis discharge and effusion liquid, have been carried out in the medical analysis laboratory of Bechar for seven months. Results: The obtained results showed that out of 1458 samples, 506 cases were positive (34.7 %), for some infections, there is a relationship correlation between the infections' frequency and their prevalence with the age and gender of patients, as factors; which the female gender presents 74.7 % of positive cases, a sex-ratio less than 1; besides, the most affected population is aged between 25 and 39 years old. The isolated microbial species, which are the most incriminated agents responsible for the studied infections, were mainly Escherichia coli with an isolation frequency of 87.15 %, followed by coagulase-positive Staphylococci CoPS (5.13 %), Streptococcus sp (3.16 %), fungal species Candida albicans (1.58 %), Coagulase-negative Staphylococci Co NS (1.18 %). However, less than 2 % of infectious agents were recorded for the bacterial strains P. aeruginosa, K. pneumoniae and Enterococcus sp. Conclusion : This study can provide a platform for an effective prevention strategy and can be useful for epidemiological prediction with a decision-making. [ABSTRACT FROM AUTHOR]

The medicinal value of the plants is due to their chemical components that bring a definite physiological action on the human body to prevent the diseases. In this work, we investigated the antimicrobial activity of leaves' extracts of Quercus robur L., collected from the Algerian upper highlands, on ten bacterial strains and one fungal strain known to be pathogenic. Firstly, we performed a qualitative phytochemical analysis, and secondly, antimicrobial activity tests performed by agar diffusion method (disc and well) with the determination of MIC by broth macro-dilution method. Given the results, it appears that obtained macerates of Q. robur L. were rich in bioactive phytoconstituents such as alkaloids, anthraquinones, saponins, tannins and other components. The yield of aqueous and methanolic macerates of leaves was 8.5±1.41 and 22.4±4.36% respectively. The bacterial resistance was relatively important to several antibiotics namely ampicillin, amoxicillin+clavulanic acid for strains of Escherichia coli and Salmonella sp. However, Staphylococcus aureus strains were resistant to fusidic acid, to penicillin and to oxacillin; while Enterococcus faecalis was resistant to fusidic acid, penicillin, oxacillin and ticarcillin. The antibacterial activity of the macerates towards tested microbial strains showed that the aqueous and methanolic macerates of the leaves were proportional to the tested concentration and active not only against Gram-positive and Gram-negative bacteria, but also on the fungal species Candida albicans. The estimated MIC for Escherichia coli, Enterococcus faecalis and Staphylococcus aureus was in the order of 10 mg/mL, which seems more effective than towards Salmonella sp, Klebseilla pneumoniae, Pseudomonas aeruginosa and C. albicans which were in the order of 30 mg/mL. These preliminary results confirm that the part of the studied plant had a very good antimicrobial activity that was proportional to the serial concentrations of the tested extracts. [ABSTRACT FROM AUTHOR]

During the recent years, scientific research focused on the bioactive compounds of plants that are intended for phytopharmaceutical use. Much research has highlighted the role of the oxidative phenomenon in the initiation of disease. Consequently, the selection of traditional plants to discover of new drugs presents a great importance, in this context, the present study aims to measure the antioxidant activity of a medicinal plant "Anastatica hierochuntica L." in the region of Tindouf (Far Southwest of Algeria). The study of antioxidant potency by DPPH method of three macerates of A.hierochuntica L., showed that aqueous and methanolic macerates presented interesting antioxidant activities expressed by the IC50 giving the results 0,143±0,0074 and 0,257±0,012mg/ml respectively. In addition, the methanolic macerate of the stems presented a medium activity estimated at 0,358 ± 0,158mg/ml. However, the aqueous and etheric macerates of the stems have given a very low antioxidant activity revealed by the values 1,0290 ± 0,115 and 2,08 ± 0,130 mg/ml, respectively. These preliminary results have allowed us to predict that natural substances in the plant can be considered as important source of compounds with significant antioxidant properties, which suggests their application in pharmaceutical and food industry could be quite accurate. [ABSTRACT FROM AUTHOR]