Protein fraction from Syzygium cumini L. (Skeels) seeds active against bacteria isolated from bovine mastitis

Mastitis, an inflammation of the mammary gland, is the costliest production disease of dairy cattle around the world. The treatment is based on antibiotic therapy, but the therapeutic efficacies of the drugs are decreasing due to the development of antimicrobial resistance. Aiming to evaluated the potential use of herbal compounds on infections of mammary glands, the in vitro activity of Syzygium cumini L. (Skeels) seeds protein fraction was tested against different isolated bacteria from bovine mastitis (Staphylococcus aureus, Staphylococcus intermedius, coagulase-negative Staphylococcus, Staphylococcus hyicus, Streptococcus uberis, α-hemolytic Streptococcus, Streptococcus dysgalactiae, Streptococcus bovis and Enterococcus faecalis). The tests were carried using protein fraction obtained by sulfate ammonium precipitation, dialysis and lyophilization. The agar diffusion method was used and this fraction showed activity against S. uberis, with an inhibition halo of 12mm, α-hemolytic Streptococcus (10,5mm), S. intermedius (15mm), coagulase-negative Staphylococcus (16mm) and S. aureus (18mm). These results showed that the S. cumini seeds protein fraction could represent an interesting alternative method for mastitis control. The formulations based on this natural product will be tested, aiming to development an alternative treatment for antibiotic therapy, with reduced costs and risk of residues on milk.