title: Efficacy of the biocontrol yeast Pichia anomala during long-term storage of moist feed grain under different oxygen and carbon dioxide regimens.
abstract: The yeast Pichia anomala inhibits the spoilage mold Penicillium roqueforti in laboratory experiments with high-moisture wheat in malfunctioning airtight storage. The ability of P. anomala to prevent mold growth during 14 months of grain storage was evaluated in outdoor silos with different air permeabilities. Freshly harvested wheat in 160-kg portions was inoculated with 10(2) colony-forming units (cfu) g(-1) P. roqueforti, alone or together with 10(4) cfu g(-1) P. anomala. During the first month P. anomala increased to about 10(6) cfu g(-1) in the treated silos to reach 10(7) cfu g (-1) after 9 months. Naturally occurring P. anomala in the untreated silos increased from 10(2) to about 10(3) cfu g(-1) during the first month and reached the same level as the treated silos after 9 months. Oxygen levels were reduced below the detection limit within 1 day, while carbon dioxide levels increased to 80-90% during the first month. P. roqueforti did not grow in wheat treated with P. anomala, regardless of silo permeability, but had increased to 10(5) cfu g(-1) in the untreated silos after 14 months of storage.
authors.affiliation: Department of Microbiology, Swedish Institute of Agricultural Sciences (SLU), Uppsala, Sweden. ulrika.druvefors@mikrob.slu.se
authors.forename: Ulrika
authors.initials: U
authors.lastname: Druvefors
authors.forename: Nils
authors.initials: N
authors.lastname: Jonsson
authors.forename: Marianne E
authors.initials: ME
authors.lastname: Boysen
authors.forename: Johan
authors.initials: J
authors.lastname: Schnürer
mesh_terms: D000898:Antibiosis; D002245:Carbon Dioxide / Q000494:pharmacology*; D005511:Food Handling / Q000379:methods; D005516:Food Microbiology; D005519:Food Preservation; D010100:Oxygen / Q000494:pharmacology*; D010407:Penicillium / Q000254:growth & development / Q000502:physiology; D010572:Pest Control, Biological; D010843:Pichia / Q000187:drug effects / Q000502:physiology*; D013696:Temperature; D014908:Triticum / Q000382:microbiology; D014867:Water
chemical_list: D014867:Water; D002245:Carbon Dioxide; D010100:Oxygen