Avaliação da atividade antibacteriana de actinobactérias do semiárido

Abstract

Actinobacteria is a phylum of Gram-positive bacteria with a high content of guanine and cytosine in their DNA. They are found in various environments such as soil, marine sediments and compost. They are capable of adapting to severe environmental conditions, such as those prevalent in the Brazilian semi-arid region, as they produce enzymes that withstand wide variations in temperature, pH and salinity. They produce a variety of secondary metabolites of pharmacological and commercial interest. With the discovery of actinomycin, several antibiotics were discovered especially from the genus Streptomyces. Antibacterial resistance presents itself as a threat to public health, which generates the need for research for new antimicrobial agents. The aim of this study was to screen the antibacterial activity of actinobacteria strains isolated from the Brazilian semi-arid region against Bacillus subtilis and Escherichia coli. The presence of an inhibition halo around the actinobacteria pellet indicates its action against the standard strain, while the absence of the halo shows that the tested strain does not have inhibitory activity. A value of 37.9% of the strains showed activity against Bacillus subtilis, while 31% for Escherichia coli. Strains SN04, SN05, SN06, SN08, SN09, SN10, SN20, SN24, SN31, SN32, SN35 and SN36 did not show inhibitory action against any standard strain. Three strains were active for both Bacillus subtilis and Escherichia coli, they were SN15, SN21 and SN30. The result of the screening points to the possible potential for the production of antibiotic substances from strains of actinobacteria isolated from the semi-arid region, which highlights the importance of future research that explores this therapeutic potential in more detail.