title: Mycoflora dynamics analysis of Korean traditional wheat-based nuruk.
abstract: The growing popularity of traditional Korean alcoholic beverages has led to a demand for quality enhancement of the traditional starter culture nuruk, which consists primarily of wheat. Therefore, this study focused on mycoflora characterization and the temporal variations in traditional wheat-based nuruks fermented at two representative traditional temperature conditions for 30 days. Nuruk A was fermented at a constant temperature of 36°C for 30 days and nuruk B was fermented at a high initial temperature of 45°C for 10 days followed by 35°C for 20 days. The average mycoflora load in the two different nuruk conditions did not vary significantly between the 0 and 30 day cultures, and a maximum load of 8.39 log CFU/g was observed for nuruk A on culture day 3 and 7.87 log CFU/g for nuruk B on culture day 30. Within two samples, pH was negatively correlated with temporal changes in mycoflora load. The pH of nuruk A was significantly lower than that of nuruk B at all of the time points evaluated. Culture-dependent characterization led to the identification of 55 fungal isolates belonging to 9 genera and 15 species, with the most prominent genera comprising Lichtheimia, Penicillium, Trametes, Aspergillus, Rhizomucor, and Mucor. A total of 25 yeast isolates were characterized belonging to 6 genera and 7 species, the most prominent among which were Rhodotorula, Pichia, Debaryomyces, Saccharomycopsis, and Torulospora. Mycofloral community dynamics analysis revealed that both samples A and B varied considerably with respect to the fungal communities over a span of 30 days.
authors.affiliation: Department of Molecular Biology, Department of Bioactive Material Sciences, Center for Fungal Pathogenesis, Chonbuk National University, Jeonju, 561-756, Republic of Korea.
authors.forename: Jyotiranjan
authors.initials: J
authors.lastname: Bal
authors.forename: Suk-Hyun
authors.initials: SH
authors.lastname: Yun
authors.forename: Ha-Yeon
authors.initials: HY
authors.lastname: Song
authors.forename: Soo-Hwan
authors.initials: SH
authors.lastname: Yeo
authors.forename: Jae Hyun
authors.initials: JH
authors.lastname: Kim
authors.forename: Jung-Mi
authors.initials: JM
authors.lastname: Kim
authors.forename: Dae-Hyuk
authors.initials: DH
authors.lastname: Kim
mesh_terms: D000434:Alcoholic Beverages / Q000382:microbiology; D001230:Aspergillus / Q000302:isolation & purification; D044822:Biodiversity; D005285:Fermentation; D005658:Fungi / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification*; D009089:Mucor / Q000302:isolation & purification; D010407:Penicillium / Q000302:isolation & purification; D020103:Rhizomucor / Q000302:isolation & purification; D013696:Temperature; D055454:Trametes / Q000302:isolation & purification; D014908:Triticum / Q000382:microbiology*; D015003:Yeasts / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification*