Characterization and DNA Plasmid Analysis of Ropy Pediococcus spp. Strains Isolated from Basque Country Ciders

K Fernandez; M Dueñas; A Irastorza; A Bilbao; G Del Campo

doi:10.4315/0362-028X-59.1.35

Characterization and DNA Plasmid Analysis of Ropy Pediococcus spp. Strains Isolated from Basque Country Ciders

J Food Prot. 1996 Jan;59(1):35-40. doi: 10.4315/0362-028X-59.1.35.

Authors

K Fernandez¹, M Dueñas¹, A Irastorza¹, A Bilbao¹, G Del Campo¹

Affiliation

¹ Departamento de Química Aplicada, Facultad de Química, Universidad del País Vasco, 20080 San Sebastián, Gipuzkoa, Spain.

PMID: 31158968
DOI: 10.4315/0362-028X-59.1.35

Abstract

Ten strains of Pediococcus spp. causing ropiness were isolated from Basque Country spoiled ciders and characterized with regards to growth at different pHs, temperatures, and ethanol and SO₂ concentrations. They grew well at pHs above 3.7 and failed to grow at temperatures over 37°C. In addition, they were tolerant to 10% ethanol and to 15, 25, and 50 mg/l total SO₂ (pH 3.8). A selected ropy strain was used to carry out plasmid DNA analysis; the agarose gel pattern showed the presence of 6 bands of plasmid DNA. Plasmid-curing experiments with ethidium bromide and novobiocin suggested that the ropy phenotype was encoded by plasmid DNA. In addition, this nonropy strain lost its resistance to oleandomycin after curing trials.

Keywords: Ropy phenotype; cider; gel electrophoresis; lactobacilli; plasmid DNA.