Soil-derived actinobacteria with antibacterial and antiparasitic activities
Keywords:
Actinomycetes, Toxoplasmosis, soil, enzyme, bioactive compoundsAbstract
Microorganisms synthesise a wide range of bioactive compounds that can serve as drugs to treat various infections. Toxoplasmosis is a widespread zoonotic infection caused by the protozoan parasite Toxoplasma gondii, for which no existing drugs can completely eliminate latent tissue cysts. Thus, actinomycetes were isolated from soil samples in Mongolia and evaluated for their antibacterial and antiparasitic activities. All the crude extracts inhibited the growth of T. gondii by more than 50%. Notably, the crude extract from MNL-50 exhibited anti-protozoal activity with an IC50 of 21.9 µg/ml. Moreover, bioactive compounds derived from natural resources represent a promising approach for combating bacterial infections. Therefore, we examined these compounds for their antibacterial properties against Escherichia coli and Staphylococcus aureus. The enzymatic activities of actinomycetes were also assessed. Among the tested isolates, all strains showed the ability to degrade amylase and lipase, indicating broad starch-degrading potential. Phylogenetic analysis of the selected strain MNL-50 revealed that it shares the greatest similarity with Streptomyces bacillaris, as determined by 16S rRNA gene sequencing analysis. This study highlights the potential of soil actinomycetes as sources of antiprotozoal and antibacterial compounds, and suggests that further investigation is warranted.
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Copyright (c) 2026 Pagmadulam Baldorj, Yoshifumi Nishikawa, Erdenechimeg Shagdar, Bolor-Oyut Batbayar, Rentsenkhand Tserennadmid
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