title: Inactivation of Geobacillus stearothermophilus in canned food and coconut milk samples by addition of enterocin AS-48.
abstract: The cyclic bacteriocin enterocin AS-48 was tested on a cocktail of two Geobacillus stearothermophilus strains in canned food samples (corn and peas), and in coconut milk. AS-48 (7 microg/g) reduced viable cell counts below detection levels in samples from canned corn and peas stored at 45 degrees C for 30 days. In coconut milk, bacterial inactivation by AS-48 (1.75 microg/ml) was even faster. In all canned food and drink samples inoculated with intact G. stearothermophilus endospores, bacteriocin addition (1.75 microg per g or ml of food sample) rapidly reduced viable cell counts below detection levels and avoided regrowth during storage. After a short-time bacteriocin treatment of endospores, trypsin addition markedly increased G. stearothermophilus survival, supporting the effect of residual bacteriocin on the observed loss of viability for endospores. Results from this study support the potential of enterocin AS-48 as a biopreservative against G. stearothermophilus.
authors.affiliation: Area de Microbiología, Departamento de Ciencias de la Salud, Facultad de Ciencias Experimentales, Universidad de Jaén, 23071 Jaén, Spain.
authors.forename: Pilar Martínez
authors.initials: PM
authors.lastname: Viedma
authors.forename: Hikmate
authors.initials: H
authors.lastname: Abriouel
authors.forename: Nabil
authors.initials: N
authors.lastname: Ben Omar
authors.forename: Rosario Lucas
authors.initials: RL
authors.lastname: López
authors.forename: Eva
authors.initials: E
authors.lastname: Valdivia
authors.forename: Antonio
authors.initials: A
authors.lastname: Gálvez
mesh_terms: D001430:Bacteriocins / Q000494:pharmacology*; D003059:Cocos / Q000382:microbiology*; D015169:Colony Count, Microbial; D003257:Consumer Product Safety; D005516:Food Microbiology; D005519:Food Preservation / Q000379:methods*; D001411:Geobacillus stearothermophilus / Q000187:drug effects / Q000254:growth & development*; D006801:Humans; D018532:Pisum sativum / Q000382:microbiology; D013696:Temperature; D013997:Time Factors; D014675:Vegetables / Q000382:microbiology; D003313:Zea mays / Q000382:microbiology
chemical_list: D001430:Bacteriocins; C466236:enterocin AS-48, Enterococcus faecalis