Identification and killer activity of a yeast contaminating starter cultures of Saccharomyces cerevisiae strains used in the Turkish baking industry

Izgu, F
Altinbay, D
Yucelis, A
The yeast contaminating the starter cultures of Saccharomyces cerevisiae fermentation strains BSP 1-4, used in the Turkish baking industry, was identified as Candida tropicalis with a killer phenotype. The activity of the killer toxin against the industrial strains was optimum at pH 3.9 and 4.1 at 22-25 degrees C. The activities of some killer toxin-producing yeasts of known phenotypes against C. tropicalis were determined. Among the yeasts tested S. cerevisiae K3 and Hansenula anamola K8 were inhibitory to C. tropicalis. This led to a conclusion that K8 and/or K3 killer traits could be used for the construction of industrial strains resistant to C. tropicalis contamination. (C) 1997 Academic Press Limited.


Immunization of the industrial fermentation starter culture strain of Saccharomyces cerevisiae to a contaminating killer toxin-producing Candida tropicalis
Izgu, F; Altinbay, D; Derinel, Y (Elsevier BV, 2004-12-01)
K3 killer trait was introduced into the fermentation starter strain of Saccharomyces cerevisiae BSP 1 in order to construct immune industrial strain that produces K3 type killer toxin and was resistant to Candida tropicalis (K+) contamination. Protoplasts of respiration-deficient Rhodegrees strain of S. cerevisiae NCYC 761 (K3) and S. cerevisiae BSP 1 were fused. The resulting respiration-competent hybrid with K3 type killer activity was selected on media containing a non-fermentable carbon source and by a ...
Molecular methods for identification of Lactobacillus delbrueckii subsp bulgaricus and Streptococcus thermophilus using methionine biosynthesis and 16S rRNA genes
Cebeci, Aysun; Gültekin, Güzin Candan (Cambridge University Press (CUP), 2008-11-01)
Yoghurt and starter culture producers are still searching strains of Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus to produce healthier yogurt with longer shelf life, better texture, taste and quality. However, selective identification of Lb. delbrueckii subsp. bulgaricus and Strep. thermophilus from a mixed population using microbiological and biochemical methods is difficult, time consuming and may not be accurate. In this study, a quick, sensitive and accurate method is propo...
Differentiation of Anatolian honey samples from different botanical origins by ATR-FTIR spectroscopy using multivariate analysis
Gok, Seher; Severcan, Mete; Goormaghtigh, Erik; KANDEMİR, İRFAN; Severcan, Feride (Elsevier BV, 2015-03-01)
Botanical origin of the nectar predominantly affects the chemical composition of honey. Analytical techniques used for reliable honey authentication are mostly time consuming and expensive. Additionally, they cannot provide 100% efficiency in accurate authentication. Therefore, alternatives for the determination of floral origin of honey need to be developed. This study aims to discriminate characteristic Anatolian honey samples from different botanical origins based on the differences in their molecular co...
Feedstock optimization of in-vessel food waste composting systems for inactivation of pathogenic microorganisms
Çekmecelioğlu, Deniz; Graves, RE (International Association for Food Protection, 2005-03-01)
An optimum composting recipe was investigated to reduce pathogenic microorganisms in a forced-aerated in-vessel system (55 liters). The feedstocks used for in-vessel composting were food waste, cow manure, and bulking materials (wood shavings and mulch hay). A statistical extreme vertices mixture design method was used to design the composting experiments and analyze the collected data. Each mixture (nine total) was replicated randomly three times. Temperature was monitored as an indicator of the efficiency...
Effects of plasmid curing on antibiotic susceptibility, phage type, lipopoly saccharide and outer membrane protein profiles in local Salmonella isolates
İçgen, Bülent; Gültekin, Güzin Candan; Özcengiz, Gülay (Elsevier BV, 2001-12-01)
Five different Salmonella isolates (four Salmonella enteritidis and one Salmonella havana) of human, chicken or egg origin which all expressed smooth lipopolysaccharide were subjected to plasmid curing Upon this treatment, four isolates lost at least one of their resident plasmids while all five isolates became rough in their LPS profiles, Two of the S. enteritidis isolates, CA13 and CE7 were found to convert phage types (PTs) as well. The phage type conversion in CA13 from PT6 to PT21 was found to be accom...
Citation Formats
F. Izgu, D. Altinbay, and A. Yucelis, “Identification and killer activity of a yeast contaminating starter cultures of Saccharomyces cerevisiae strains used in the Turkish baking industry,” FOOD MICROBIOLOGY, pp. 125–131, 1997, Accessed: 00, 2020. [Online]. Available: