Aim:This work aimed to evaluate the biological activity of the leaf extracts of Juniperus thurifera L., which is an Algerian endemic tree that belongs to the family of Cupressaceae.Materials and Methods:The plant leaves were extracted in solvents of increasing polarity to obtain different extracts such as methanol, petroleum ether, chloroform, ethyl acetate, and aqueous extracts (MeE, PEE, ChlE, EtAE, and AqE). The antioxidant activity of four extracts (MeE, ChlE, EtAE, and AqE) was assessed by trapping test of 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical. The evaluation of antibacterial activity of MeE, ChlE, EtAE, and PEE was done using the disk diffusion method on solid agar.Results:The three extracts of EtAE, AqE, and MeE showed high antiradical activity toward the DPPH radical (IC50=29.348 µg/mL, 37.538 µg/mL, and 52.573 µg/mL, respectively), while the lowest radical scavenging activity was expressed by the ChlE (IC50=70.096 µg/mL). These extracts were active only toward the Gram-positive bacteria (Staphylococcus aureus ATCC and methicillin-resistant S. aureus) at different concentrations, and the highest activity was obtained with the ChlE with an inhibition diameter of 14 mm at the concentration of 1 g/mL. No inhibition was detected for all of these extracts against the Gram-negative tested strains (Escherichia coli ATCC, Pseudomonas aeruginosa ATCC, and Enterobacter cloacae (extended spectrum β-lactamase).Conclusion:From this study, on the one hand, it was concluded that J. thurifera L. leaves extracts exhibited a very intense antioxidant potential toward the DPPH radical, and on the other hand, the antibacterial activity showed an action spectrum exclusively toward the Gram-positive bacteria.

Bovine respiratory disease (BRD) is common in calves in Algeria, but to date, Mycoplasma bovis has never been monitored as a potential etiological agent. Here, to assess the presence (direct detection) and circulation (indirect detection) of M. bovis, broncho-alveolar lavage fluids (BALF) and serum samples were collected from 60 veal calf farms in Algeria. A commercial ELISA kit (ID Screen® ELISA) was used to screen for the presence of specific antibodies against M. bovis in 351 blood sera collected from both diseased and healthy calves, and 69% (241 sera) tested positive. BALFs from the 176 diseased calves were used to screen for M. bovis by real-time-PCR (rt-PCR), and 102 (58%) tested positive. A non-exhaustive set of 53 clones were isolated from 44 calves and further subtyped using polC gene sequencing. No predominant subtype was found, and two clones exhibited a new subtype. Fourteen clones were further characterized by multilocus sequence typing, and results showed a high degree of genetic diversity, with some clones having new alleles and subtypes. The minimum inhibitory concentrations (MICs) of 5 antimicrobials regularly used to treat BRD was determined on 45 clones. Susceptibility profiles showed very broad diversity, confirming the variety of clones actively circulating. We detected clones with high MICs, including increased MICs of enrofloxacin (n = 5). This is the first study to report the presence of M. bovis in Algeria in calves with BRD. This research also finds broad genetic and phenotypic diversity in the actively circulating isolates.

Background: Several animal species may act as a possible reservoir for transmission of MRSA to human. The aim of this study was to determine the antibiotic resistance profiles of Staphylococci from animals.Methods: A total of 754 nasal and rectal swab samples collected from apparently healthy animals at Batna and Setif governorate, eastern Algeria. For this purpose, we studied the antimicrobial susceptibility of the isolates by conventional methods (Disk diffusion test and methicillin resistance by Cefoxitin disk diffusion test).Result: The overall prevalence of S. aureus isolates from 754 samples was 43.61%, with a high rate of S. aureus isolation in rabbits (92%). Goats, bovine, dogs, cats, horses, poultry presented a medium prevalence with 31.91%, 25%, 23.75% 21.25%,15% and 15% respectively, while the lowest rate was observed in sheep with 10%. MRSA were isolated in all animal species (29.46%). All detected isolates were multiple drug resistant (MDR). A complete resistance (100%) was noted for ciprofloxacin and gentamicin in sheep and horses and to penicillin in dogs. MRSA is a serious problem for human and animal health; therefore, several experiments must be carried out to demonstrate possible transmission of MRSA between companion or food-chain animals and humans, as well as some MRSA clones of human origin that have adapted to new animal hosts eventually by losing useless virulence factors or acquiring new mobile genetic elements.

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