title: Pichia pastoris X-33 has probiotic properties with remarkable antibacterial activity against Salmonella Typhimurium.
abstract: Probiotics are live microorganisms which are beneficial for the host when ingested at high enough concentrations. The methylotrophic yeast Pichia pastoris is widely used as heterologous protein production platform. However, its use as probiotic is poorly studied. The objective of this study was to evaluate some probiotic properties of the P. pastoris strain X-33 wild type. The resistance to in vitro and in vivo gastrointestinal conditions, stability in feed, safety, and antibacterial activity against Salmonella Typhimurium were evaluated. The yeast remained viable and persisted at appropriate concentration in the diet for at least 2 months, survived the stresses of the gastrointestinal tract in vitro and in vivo, caused no behavioral changes or lesions when administered to mice, inhibited the growth of S. Typhimurium in culture media, and reduced adhesion of the bacteria to the intestinal cells HCT-116. In the challenge experiment with a LD50 of virulent S. Typhimurium strain, mice supplemented with the yeast had a higher survival rate (50 % when administered by gavage and 80 % via the diet, compared with 20 and 50 %, respectively, in the control group). In addition, the S. Typhimurium concentration in the intestine of the surviving mice was lower; the score of intestinal lesions, lower; and the pathogen, not detected in the liver, spleen, and feces when compared to the control group (p < 0.05). It was concluded that the yeast Pichia pastoris X-33 has probiotic properties with remarkable antibacterial activity against S. Typhimurium.
authors.affiliation: Nucleo de Biotecnologia, Centro de Desenvolvimento Tecnológico, Universidade Federal de Pelotas, Campus Universitário, Capão do Leão, Caixa Postal 354, Pelotas, RS, 96010-900, Brazil.
authors.forename: Rodrigo Correa
authors.initials: RC
authors.lastname: França
authors.forename: Fabricio Rochedo
authors.initials: FR
authors.lastname: Conceição
authors.forename: Marcelo
authors.initials: M
authors.lastname: Mendonça
authors.forename: Louise
authors.initials: L
authors.lastname: Haubert
authors.forename: Gabriela
authors.initials: G
authors.lastname: Sabadin
authors.forename: Patrícia Diaz
authors.initials: PD
authors.lastname: de Oliveira
authors.forename: Marta G
authors.initials: MG
authors.lastname: Amaral
authors.forename: Wladimir Padilha da
authors.initials: WP
authors.lastname: Silva
authors.forename: Ângela Nunes
authors.initials: ÂN
authors.lastname: Moreira
mesh_terms: D000818:Animals; D000898:Antibiosis; D001422:Bacterial Adhesion; D041981:Gastrointestinal Tract / Q000382:microbiology; D051379:Mice; D010843:Pichia / Q000502:physiology*; D019936:Probiotics / Q000032:analysis*; D012486:Salmonella typhimurium / Q000254:growth & development* / Q000502:physiology