Aquatic plants as potential sources of antimicrobial compounds active against bovine mastitis pathogens

摘要

Resistance of pathogens to common veterinary antibiotics hampers mastitis treatment and motivates the discovery of new antimicrobials. In this?study, extracts from two aquatic plants,?Salvinia auriculata?and?Hydrocleys nymphoides,?were assayed against bovine mastitis pathogens. Selected parts of plants were?extracted with different solvents.?The extracts showed activity only against the Gram-positive strains tested and the largest inhibition zones were seen for hexane extracts. The minimum inhibitory concentration values ranged from 0.2 to 1.0 mg/ml. Growth ofStreptococcus agalactiae?in the presence of different extracts with concentrations below MIC reduced the number of CFU/ml by more than 90%. Sub-MIC concentrations of the hexane extracts prepared from roots of?S. auriculata?inhibited approximately 50% of biofilm formation. Greater reduction was achieved for?ethanol extract prepared from leaves of?H. nymphoides.?We concluded?that these aquatic plants are potential sources for the investigation of new antimicrobial compounds.