Avaliação da avid vegetal de jambú (Spilanthes acmella) em isolados de Staphylococcus spp. provenientes de amostras de leite de bovinos

Abstract

In Brazil, the genus Staphylococcus spp is considered as the main causal agent of bovine mastitis. Several studies indicate that both S. aureus bacteria and coagulase-negative staphylococci, in addition to being the most frequent and found in mastitis, have an increasing pattern of resistance to antimicrobials, which are opportunistic, leading to intramammary infections and decreasing milk quality. One of the alternatives found to help reduce costs and, mainly, to minimize the processes of microbiological resistance is the use of phytotherapeutic agents (or derivatives thereof) as therapeutic adjuvant agents. Among these potential therapeutic alternatives, we find Jambu (Spilanthes acmella), a plant rich in bioactive isobutyl amides. Due to the presence of this substance, the plant has traditional applications in pharmaceutical products, food, and products for health and personal care. Thus, the objective of this work was to evaluate the antibacterial effects of the Jambu plant extract in isolates of Staphylococcus spp. from bovine milk samples. For this purpose, 60 milk samples were collected from cows from municipalities in the interior of the State of Amazonas. These samples were made for the detection, counting, and confirmation of Staphylococcus spp and, from these, the minimum inhibitory concentration test of the Jambu plant extract. As a result, Of the 60 milk samples, it was possible to obtain colonies characteristic of Staphylococcus spp. of 56 (93.3%) samples. Of these, 56 strains were obtained, of which 19 (33.9%) were characterized as Staphylococcus aureus and 37 (66.1%) as Staphylococcus spp. All 56 strains showed some level of sensitivity to the Jambu plant extract, from the initial dilution (20% concentration) to the final dilution (0.039%). In our study, we obtained a high percentage of isolation (93.3%) of Staphylococcus spp from the samples, with 33.9% representing Staphylococcus aureus and 66.1% of coagulase-negative staphylococcus. In this scenario, we found that the Jambu plant extract inhibited the growth of Staphylococcus spp. isolated from bovine milk samples, in all tested concentrations, except the last one (at 0.0195%). For isolates with a lower inhibitory concentration, the effects, for the most part, behaved as bacteriostatic, whereas for isolates with a higher inhibitory concentration the effect was similar to the bactericide. We believe that these differences in effects may be linked to different levels of sensitivity of the isolates.