Djemouai, NadjetteMeklat, AtikaYoucef, Khadidja Oulad HadjNacer, AsmaSaadi, Sid AhmedVerheecke-Vaessen, Carol2024-10-252024-10-252024-12-01Djemouai N, Meklat A, Youcef KOH, et al., (2024) Diversity and bioactivity of endophytic actinobacteria associated with the roots of artemisia herba-alba asso from Algeria. Current Microbiology, Volume 81, Issue 12, December 2024, Article number 4020343-8651https://doi.org/10.1007/s00284-024-03932-1https://dspace.lib.cranfield.ac.uk/handle/1826/23127The datasets generated during and/or analyzed during the current study are available from the corresponding author upon reasonable request, while 16S rRNA data generated are available in the Genbank repository.The isolation of endophytic actinobacteria from the roots of wild populations of Artemisia herba-alba Asso, a medicinal plant collected from the arid lands of Algeria, is reported for the first time. Forty-five actinobacterial isolates were identified by molecular analysis and in vitro evaluated for antimicrobial activity and plant growth-promoting (PGP) abilities (1-Aminocyclopropane-1-carboxylic acid (ACC) deaminase activity, nitrogen fixation, phosphate and potassium solubilization, ammonia, and siderophores production). The phylogenetic relationships based on 16S rRNA gene sequences show that the genus Nocardioides (n = 23) was dominant in the sampled localities. The remaining actinobacterial isolates were identified as Promicromonospora (n = 11), Streptomyces (n = 6), Micromonopora (n = 3), and Saccharothrix (n = 2). Only six (13.33%) strains (five Streptomyces and one Saccharothrix species) were antagonistic in vitro against at least one or more indicator microorganisms. The antimicrobial activity of actinobacterial strains targeted mainly Gram-positive bacteria. The results demonstrate that more than 73% of the isolated strains had ACC deaminase activity, could fix atmospheric nitrogen and were producers of ammonia and siderophores. However, only one (2.22%) strain named Saccharothrix sp. BT79 could solubilize phosphorus and potassium. Overall, many strains exhibited a broad spectrum of PGP abilities. Thus, A. herba-alba provides a source of endophytic actinobacteria that should be explored for their potential biological activities.ElectronicenAttribution 4.0 Internationalhttp://creativecommons.org/licenses/by/4.0/31 Biological SciencesInfectious Diseases2 Zero HungerMicrobiologyAlgeriaActinobacteriaPlant RootsPhylogenyEndophytesArtemisiaRNA, Ribosomal, 16SBiodiversityNitrogen FixationSiderophoresArticle1432-09915548354028112