Bovine mastitis is characterized by inflammation of the mammary gland, usually in response to bacterial infection, affecting qualitatively and quantitatively milk production. This study aimed to determine the antibacterial activity in vitro of the hydroalcoholic extract of the bark of the pomegranate on bacteria isolated from bovine milk. The colonies of Staphylococcus spp. were resuspended in 6 MacFarland scale and adjusted its concentration by UV visible spectrophotometry at a concentration of 10(6)ml-1. The extracts were evaluated in quintuplicate in seven concentrations: from 4 up to 0.0625mg.mL-1. The sensitivity of microbial isolates was determined using the disk diffusion and the results that showed inhibition halos corresponding to values from 15mm were considered susceptible. The results were evaluated by ANOVA, Tukey test 5% using the SISVAR 5.3-DEX/UFLA. Additionally the extract was assessed as for the antioxidant activity, content of phenols and total flavonoids. The extract was diluted into seven concentrations: 25-1.000µg.mL-1, and evaluated in triplicate. The bacterial growth was inhibited starting from the concentration of 4 mg.mL-1 and antioxidant activity was observed from 50µg.mL-1, with values corresponding to 4.62% reaching the plateau of 64.90% at a concentration of 500µg.mL-1. In evaluating the radical scavenging activity, using the free radical DPPH, the extract demonstrated antioxidant activity (IC50%= 378.80µg/mL). However it has not been possible to correlate the antioxidant activity with the levels of phenols and flavonoids. Perhaps the presence of other substances alkaloids and tannins present in the extracts may have been responsible for the antioxidant activity found. It was concluded that the hydroalcoholic extract of Punica granatum Linn. has antimicrobial activity against Staphylococcus spp., demonstrating potential benefit for the control of bovine mastitis.
Mastitis; antimicrobial; natural extract; medicinal plants; organic production; Pomegranate
