title: Deterioration of expanded polystyrene caused by Aureobasidium pullulans var. melanogenum.
abstract: An expanded-polystyrene factory located in northern Buenos Aires reported unusual dark spots causing esthetic damage in their production. A fungal strain forming black-olive colonies on extract malt agar medium was isolated from the damaged material and identified as Aureobasidium pullullans var. melanogenum. This fungus is particularly known for its capacity to produce hydrolytic enzymes and a biodegradable extracellular polysaccharide known as pullulan, which is used in the manufacture of packaging material for food and medicine. Laboratory tests were conducted to characterize its growth parameters. It was found that the organism was resistant to a wide range of pHs but did not survive at temperatures over 65°C. The proposed action plan includes drying of the material prior to packaging and disinfection of the machinery used in the manufacturing process and of the silos used for raw material storage.
authors.affiliation: Laboratorio de Micología Experimental, Departamento de Biodiversidad y Biología Experimental, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Intendente Güiraldes 2160, Ciudad Universitaria, C1428EGA Buenos Aires, Argentina. Electronic address: vccastiglia@gmail.com.
authors.forename: Valeria C
authors.initials: VC
authors.lastname: Castiglia
authors.affiliation: Laboratorio de Micología Experimental, Departamento de Biodiversidad y Biología Experimental, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Intendente Güiraldes 2160, Ciudad Universitaria, C1428EGA Buenos Aires, Argentina.
authors.forename: Francisco
authors.initials: F
authors.lastname: Kuhar
mesh_terms: D000362:Agar; D001203:Ascomycota / Q000187:drug effects / Q000254:growth & development / Q000302:isolation & purification / Q000378:metabolism*; D003470:Culture Media; D004202:Disinfectants / Q000494:pharmacology; D004352:Drug Resistance, Microbial; D005506:Food Contamination / Q000517:prevention & control; D019649:Food Industry / Q000379:methods; D018857:Food Packaging; D006863:Hydrogen-Ion Concentration; D008863:Microspheres; D011137:Polystyrenes; D013696:Temperature
chemical_list: D003470:Culture Media; D004202:Disinfectants; D011137:Polystyrenes; D000362:Agar
keywords: Industria; Industry; Management; Mancha; Manejo; Spot