title: Development of multiplex loop-mediated isothermal amplification assays to detect medically important yeasts in dairy products.
abstract: Rapid detection of yeast contamination is important in the food industry. We have developed loop-mediated isothermal amplification (LAMP) assays to detect the emerging opportunistic pathogenic yeasts: Candida albicans, Candida glabrata, Candida tropicalis, the Candida parapsilosis group, Trichosporon asahii, and Trichosporon mucoides. These yeasts may cause deep-seated candidiasis or trichosporonosis. Four LAMP primer sets specific for Candida were designed to target the internal transcribed spacer 2 (ITS2) region between the 5.8S and 26S rRNA genes, and two LAMP primer sets specific for Trichosporon were designed to target the intergenic spacer 1 (IGS1) region between the 26S and 5S rRNA genes. The LAMP assays could detect these yeasts in a range between 10(0) and 10(3)  cells mL(-1) in a contaminated dairy product within 1 h. We also developed multiplex LAMP assays to detect these Candida or Trichosporon species in a single reaction. Multiplex LAMP assays can detect contamination if at least one of the target species is present; they are more time- and cost-efficient than conventional methods and could detect target yeasts with sensitivity close to that of the LAMP assays. Multiplex LAMP assays established in this study can be used as a primary screening method for yeast contamination in food products.
authors: Yakult Central Institute for Microbiological Research, Kunitachi, Tokyo, Japan.
authors: Kohei
authors: K
authors: Kasahara
authors: Hiroshi
authors: H
authors: Ishikawa
authors: Sumie
authors: S
authors: Sato
authors: Yasuhisa
authors: Y
authors: Shimakawa
authors: Koichi
authors: K
authors: Watanabe
mesh_terms: D002175:Candida / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification*; D017931:DNA Primers / Q000235:genetics; D004271:DNA, Fungal / Q000235:genetics; D021903:DNA, Ribosomal Spacer / Q000235:genetics; D003611:Dairy Products / Q000382:microbiology*; D008828:Microbiological Techniques / Q000379:methods*; D021141:Nucleic Acid Amplification Techniques / Q000379:methods*; D012680:Sensitivity and Specificity; D013997:Time Factors; D014250:Trichosporon / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification*
chemical_list: D017931:DNA Primers; D004271:DNA, Fungal; D021903:DNA, Ribosomal Spacer
keywords: Candida; Trichosporon; food; loop-mediated isothermal amplification; multiplex; yeast