title: A psychrotrophic Burkholderia cepacia strain isolated from refrigerated raw milk showing proteolytic activity and adhesion to stainless steel.
abstract: The proteolytic activity of a psychrotrophic strain of Burkholderia cepacia isolated from refrigerated raw milk was characterized. Bur. cepacia produced proteolytic activity during growth at refrigeration temperature, with maximum activity at pH 6-7. The enzyme showed relative thermal stability in the range 40-50°C during 25 min, and maintained 80% its initial activity at 76°C/30 s. Milk coagulation assay showed that the crude protease from Bur. cepacia caused coagulation from day 2 for skimmed milk, whereas coagulation was observed from day 5 for whole milk. The adherence of this strain to stainless steel was evaluated, and the substrata had around 107 CFU/cm2 after 15 to 60 min incubation. Results on biofilm development suggest that this bacterium could adhere and to form biofilms even at refrigeration temperatures. These results indicate that Bur. cepacia may represent a potential hazardous to milk and dairy products.
authors: Instituto de Ciência e Tecnologia de Alimentos, Universidade Federal do Rio Grande do Sul, 91501-970 Porto Alegre, Brasil.
authors: Maria de Fátima Barros Leal
authors: Mde F
authors: Nörnberg
authors: Marilene Lenz
authors: ML
authors: Mentges
authors: Silvana Terra
authors: ST
authors: Silveira
authors: Eduardo César
authors: EC
authors: Tondo
authors: Adriano
authors: A
authors: Brandelli
mesh_terms: D000818:Animals; D001422:Bacterial Adhesion; D018441:Biofilms; D016956:Burkholderia cepacia / Q000145:classification* / Q000302:isolation & purification*; D002417:Cattle; D006863:Hydrogen-Ion Concentration; D008892:Milk / Q000382:microbiology*; D059748:Proteolysis; D012034:Refrigeration; D013193:Stainless Steel; D013696:Temperature; D013997:Time Factors
chemical_list: D013193:Stainless Steel