title: Evaluation of chitosans and Pichia guillermondii as growth inhibitors of Penicillium digitatum.
abstract: Chitosans were obtained by room-temperature-homogeneous-deacetylation (RTHD) and freeze-pump-out-thaw-heterogeneous-deacetylation (FPT) from chitins purified from fermentations. Commercial chitosan was deacetylated by three-FPT-cycles. Chitosans and Pichia guillermondii were evaluated on the growth of Penicillium digitatum. Medium molecular weight (M(W)) chitosans displayed higher inhibitory activity against the yeast than low M(W) biopolymers. Chitosans with low degree of acetylation (DA) were inhibitory for yeast and mould. Therefore, a low M(W) and high DA chitosan was selected for use against moulds combined with yeasts. Biopolymer and yeasts presented an additive effect, since chitosans were effective to delay spore germination, whereas yeast decreased apical fungal growth.
authors.affiliation: Universidad Autónoma Metropolitana, Departamento de Biotecnología, Laboratorio de Biopolímeros, Mexico City, Mexico.
authors.forename: Neith
authors.initials: N
authors.lastname: Pacheco
authors.forename: C Patricia
authors.initials: CP
authors.lastname: Larralde-Corona
authors.forename: Jose
authors.initials: J
authors.lastname: Sepulveda
authors.forename: Stéphan
authors.initials: S
authors.lastname: Trombotto
authors.forename: Alain
authors.initials: A
authors.lastname: Domard
authors.forename: Keiko
authors.initials: K
authors.lastname: Shirai
mesh_terms: D000107:Acetylation; D048271:Chitosan / Q000378:metabolism / Q000494:pharmacology*; D007700:Kinetics; D008855:Microscopy, Electron, Scanning; D008970:Molecular Weight; D010407:Penicillium / Q000187:drug effects* / Q000254:growth & development* / Q000648:ultrastructure; D010843:Pichia / Q000737:chemistry*; D013172:Spores, Fungal / Q000187:drug effects / Q000254:growth & development
chemical_list: D048271:Chitosan