title: Susceptibilities against bovine lactoferrin with microorganisms isolated from mastitic milk.
abstract: Antibacterial effects of bovine lactoferrin were studied in vitro against microorganisms isolated from mastitic milk in Tokachi area, Hokkaido, Japan. Microorganisms isolated were Escherichia coli (11 isolates), Klebsiella pneumoniae (5 isolates), enterococci (8 isolates), Staphylococcus aureus (10 isolates), coagulase negative staphylococci (CNS, 13 isolates), streptococci (11 isolates), Prototheca zopfii (7 isolates) and yeast-like fungi (9 isolates). Lactoferrin has been known as a multifunctional protein and its antimicrobial effect is one of the most essential function of it. In order to compare their susceptibilities against lactoferrin, the minimal inhibitory concentration values were estimated by a microplate assay method using 96-well microplate, which involved measuring the optical density of the cultures. Prototheca zopfii was highly sensitive to bovine lactoferrin and complete inhibition of this microorganism was observed even at the low concentration of 7 mug/ml. On the other hand, E. coli and enterococci showed resistance against lactoferrin action and staphylococci showed strain-dependent resistance.
authors.affiliation: Dairy Science Laboratory, Department of Animal Product Science, Graduate School of Agriculture, Hokkaido University, Japan.
authors.forename: Nai-Yuan
authors.initials: NY
authors.lastname: Lee
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Kawai
authors.forename: Ichiro
authors.initials: I
authors.lastname: Nakamura
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Tanaka
authors.forename: Haruto
authors.initials: H
authors.lastname: Kumura
authors.forename: Kei-Ichi
authors.initials: K
authors.lastname: Shimazaki
mesh_terms: D000818:Animals; D001419:Bacteria / Q000187:drug effects*; D002417:Cattle / Q000378:metabolism*; D005260:Female; D005658:Fungi / Q000187:drug effects*; D007564:Japan; D007781:Lactoferrin / Q000378:metabolism / Q000494:pharmacology*; D008414:Mastitis, Bovine / Q000382:microbiology*; D008826:Microbial Sensitivity Tests; D008892:Milk / Q000382:microbiology*
chemical_list: D007781:Lactoferrin