title: Antimicrobial activity of marine sponges against coagulase-negative staphylococci isolated from bovine mastitis.
abstract: Bovine mastitis remains worldwide a major challenge for the dairy industry despite the widespread implementation of control strategies. The increasing number of coagulase-negative staphylococci (CNS) causing mastitis and of bacteria resistant to conventional antibiotics has become a serious problem in recent years. Marine sponges are a rich source of bioactive compounds, and many species can be useful for the development of new antimicrobial drugs. In the present study, 49 CNS strains were isolated from bovine mastitis cases from 21 different dairy herds kept at farms in Southeast Brazil. Strains were analyzed for antimicrobial susceptibility and mecA gene detection. Fifty-nine percent of the CNS strains were resistant to at least one of the drugs tested and 12.2% were classified as multiresistant. Three strains carried the mecA gene, confering resistance to the beta-lactamic antibiotics. In addition, the CNS strains were submitted to in vitro screening for antimicrobial activities of extracts from marine sponges. Extracts from the sponge species Cinachyrella sp., Haliclona sp. and Petromica citrina showed antibacterial activity against 61% of the CNS strains, including strains resistant to conventional antibiotics. Extracts from P. citrina showed the largest spectrum of inhibitory activity. The aqueous extract inhibited 51% of the CNS strains and presented a bactericidal effect over susceptible and multiresistant-bacteria at a minimal inhibitory concentration of 1.024μg/ml. This study shows the potential of marine sponges as new sources of antibiotics and disinfectants for the control of CNS involved in bovine mastitis.
authors.affiliation: Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio de Janeiro, Avenida Carlos Chagas Filho, 373, Cidade Universitária, 21941-590, Rio de Janeiro, Brazil. marinella@micro.ufrj.br
authors.forename: Marinella Silva
authors.initials: MS
authors.lastname: Laport
authors.forename: Palloma Rodrigues
authors.initials: PR
authors.lastname: Marinho
authors.forename: Olinda Cabral da Silva
authors.initials: OC
authors.lastname: Santos
authors.forename: Paula
authors.initials: P
authors.lastname: de Almeida
authors.forename: Maria Teresa Villela
authors.initials: MT
authors.lastname: Romanos
authors.forename: Guilherme
authors.initials: G
authors.lastname: Muricy
authors.forename: Maria Aparecida Vasconcelos Paiva
authors.initials: MA
authors.lastname: Brito
authors.forename: Marcia
authors.initials: M
authors.lastname: Giambiagi-deMarval
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001938:Brazil; D002417:Cattle; D003030:Coagulase / Q000032:analysis; D005260:Female; D008414:Mastitis, Bovine / Q000382:microbiology*; D008826:Microbial Sensitivity Tests / Q000662:veterinary; D011161:Porifera; D013210:Staphylococcus / Q000187:drug effects* / Q000302:isolation & purification
chemical_list: D000900:Anti-Bacterial Agents; D003030:Coagulase