Avaliação da bioatividade de endófitos de Polygala paniculata por abordagem OSMAC e perfil enzimático no controle de patógenos de interesse clínico

Abstract

The genus Polygala spp. occurs naturally in Brazil. The presence of alkaloids, flavonoids, terpenes, among others were reported in species of this genus. The anti-inflammatory, anxiolytic, trypanocidal and antimicrobial activities stand out. Endophytic microorganisms do not cause apparent damage to their hosts and can be isolated from healthy plant tissues and superficially disinfected. Endophytes have been considered a source of natural products, including those with antimicrobial activity for the control of pathogens. Considering the growing microbial resistance, bioprospection of new antimicrobials are necessary. This study aimed to characterize phenotypically, through micro and macroscopic analyzes, two endophytic bacterial isolates (UNK3 and ROXO16) of Polygala paniculata, and to evaluate them for the production of antimicrobials and enzymes for the control of clinical pathogens. Phenotypic analyzes showed typical colonies of actinomycetes with slow growth, irregular borders with smooth or rough surface and Gram positive bacilli of different shapes, being short or long. The evaluation of antimicrobial activity revealed that the UNK3 isolate has relative activity against Pseudomonas aeruginosa ATCC-27853, Escherichia coli ATCC 11775. Staphyloccocus aureus ATCC 29213, Salmonella (clinically) and Candida albicans ATCC 10231. It was observed activity for S. aureus, P. aeruginosa and C. albicans and negative for E coli and Salmonella. An analysis of the bipartition of the extract with ethyl acetate, followed by the antimicrobial evaluation by the disk diffusion method, revealed that the UNK3 set started the production of bioactive substances on the third day; E. coli, Salmonella, on the sixth day for P. aeruginosa, and for S. aureus on the ninth day. ROXO16 isolate, the onset of activity was on the third day against E. coli, P. aeruginosa and Salmonella and negative for S. aureus and C. albicans. Qualitative enzymatic analysis consolidated that the UNK3 isolate had cellulolytic, amylolytic, pectinolytic and proteolytic activity, while the ROXO16 isolate produced cellulase and protease. Using the OSMAC methodology, it was determined that endophytic microorganisms present an increase in the production of metabolites, the modification of the carbon source and the nitrogen source resulted in greater bioactivity and even against new microorganisms, than those incubated under normal conditions. introduce you. The results obtained so far demonstrate the promising potential of the endophytic bacteria UNK3 and ROXO16 from P.6 paniculata for the production of antimicrobials and also for future industrial applications. Keywords: Antimicrobials, Endophytes, Metabolites, Polygalaceae, Enzymatic potential, microbial resistance