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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.

To date, no studies have investigated the phytochemical screening and biological activities of Cachrys libanotis L. traditionally used for the treatment of gout and rheumatism. Therefore, we aimed to investigate, for the first time, the phytochemical contents, the xanthine oxidoreductase inhibition, antibacterial, and antioxidant activities of extracts derived from the roots of C. libanotis L. Roots were submitted to extraction and fractionation using three different solvents sequentially, in the ascending order of polarity. Subsequently, XOR was purified from bovine milk and its inhibition was evaluated using xanthine/XOR system. The antioxidant activities were assessed employed superoxide scavenging, β- carotene bleaching, DPPH scavenging, ferrous iron chelation and FRAP assays). The antibacterial activity was tested by disc diffusion assay against 11 ATCC strains. Extraction and fractionation gave crude extract (CrE), hexane extract (HxE), chloroform extract (ChE), ethyle acetate extract (EAE) and aqueous extract (AqE).  EAE exhibited the highest XOR inhibitory effect. CrE exhibited the highest effect as DPPH scavenger. All fractions exhibited a good activity against linoleate oxidation. Both CrE and AqE had an excellent chelating activity. Extracts showed a medium reducing power with greatest value exhibited by EAE. The plant extracts exhibited moderate to good antibacterial activity where the HxE extract had the strongest antimicrobial activity. From the obtained results, C. libanotis roots might be helpful in preventing or slowing the progress of gout, and it could be used as an additive in the food industry providing good protection against oxidative damage. Keywords: Cachrys libanotis, polyphenols, oxidative stress, xanthine-oxidoreductase (XOR), antimicrobial.

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