ANTIMICROBIAL ACTIVITY OF PLANT EXTRACTS IN ISOLATED MICROORGANISMS IN THE SOUTHWESTERN REGION OF PARANÁ

Infectious diseases are the leading cause of death in humans. In developing countries, infections are still the main causes of mortality and morbidity in humans, especially due to the emergence of multi-resistant microorganisms to commercial drugs. Thus, some precautions should be taken in order to reduce this situation, such as: control of the administration of antibiotics, new studies seeking the understanding of genetic mechanisms of resistance and research for development of new drugs, synthetic or natural for the fight against pathogens, especially those with a multiresistance profile. In this sense, the demand for new studies of antimicrobial compounds is a challenge for researchers, who seek alternative drugs of vegetable origin aimed at a bactericidal effect on infectious agents of major medical importance. In Brazil, a country of great biodiversity, studies have been carried out showing a great variety of chemical characteristics of the essential oils extracted from different plant species with antimicrobial potential. Among the vegetables, whose extracts present antimicrobial activity, they have been outstanding to the pecã or American walnut [Carya illinoinensis (Wangenh.) C. Koch]. Although evidence of the high antioxidant potential of pecã peel extracts, studies on antimicrobial activity are scarce, however, they point to a therapeutic alternative for the treatment of infections. The present work aimed to evaluate the antibacterial potential of the aqueous extract in four different concentrations of the pecan bark [Carya illinoinensis (Wangenh.) C. Koch] on 2 gram-positive and 3 gram-negative bacterial strains, since they are scarce antimicrobial activity. The crude plant extract of C. illinoensis shells was obtained and evaluated on the microorganisms by means of the Minimum Inhibitory Concentration Determination (MIC), Determination of Minimum Bactericidal Concentration (MBC) and Well Diffusion (DP) methods. Pecã peel extract showed bactericidal activity for all bacterial strains tested at concentrations of 15% (v / v) and 20% (v / v), except for Staphylococcus aureus, the effect of which was 15% (v / v) bacteriostatic. The potential of the aqueous extract in the treatment of infectious diseases is evidenced and encourages new studies that seek to test the properties of this natural and accessible inoculum with other microorganisms, as well as their possible mechanisms of action.