Abstract
Nuruk is a fermenting starter that is involved in the pro-duction of alcoholic beverages, and has been used in South Korea for a very long time. To analyze the fungal diversity, we collected a total of 59 nuruk samples from several com-panies and persons in 2013 to 2014, and obtained 364 iso-lates. All of the single isolated fungi were identified, both morphologically and molecularly, based on the sequences of ribosomal RNA gene [18S, ITS1-5.8S-ITS2, and 26S (D1/D2 region)]. In 46 nuruk samples out of 59 (78%), Saccharo-mycopsis fibuligera, a dimorphic yeast, was most frequently isolated. Among the filamentous fungi, Aspergillus and Lich-theimia were found in more than 50% of the samples with lower colony forming unit (CFU/g of sample) than those of yeasts. The yeasts S. fibuligera and Wickerhamomyces ano-malus were counted with maximum 1.3 – 1.8 × 108 CFU/g. Among Mucorales fungi, Lichtheimia and Mucor were iso-lated in much higher numbers than Rhizopus and Rhizo-mucor. Overall, the home-made nuruks tend to contain more diverse filamentous fungi than the commercial nuruks. To acquire industrially useful filamentous fungi and yeasts, we analyzed the enzyme activities of α-amylase, glucoamylase and acid protease associated with brewing properties for 131 strains. Aspergillus oryzae and S. fibuligera had high α- and glucoamylase activities and most isolates of Lichtheimia ramosa had high acid protease activity. For further applica-tions, 27 fungal strains were chosen based on isolation fre-quencies from nuruk, and the ability to produce useful en-zyme.
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- Review: Rhizopus sp. beyond tempeh. An Occidental approach to mold-based fermentations
José María Martín-Miguélez, Jordi Bross, Diego Prado, Esther Merino, Ramón Perisé Moré, Julián Otero, Andoni Luis Aduriz, Josué Delgado
International Journal of Gastronomy and Food Science.2025; 39: 101090. CrossRef - Analyzing fungal community succession and its correlation to flavor compounds in the Cupei fermentation process of Sichuan shai vinegar
Zhicheng Li, Yuting Liao, Cuixin Huang, Jun Liu, Xiangpeng Kong, Li Li, Zhongxuan Li, Yuan Gui
Food Microbiology.2025; 128: 104718. CrossRef - Comparative genome analyses of Aspergillus oryzae and Aspergillus flavus originated from a Korean fermentation starter, nuruk
Eunji Jeong, Jeong-Ah Seo
Food Microbiology.2025; 131: 104807. CrossRef - Protective effects of extracellular proteins extracted from Saccharomycopsis fibuligera on UVA-induced skin aging
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International Journal of Biological Macromolecules.2025; 318: 145315. CrossRef - Unravelling the transcriptomic dynamics of Hyphopichia pseudoburtonii in co-culture with Botrytis cinerea
Evelyn Maluleke, Neil Paul Jolly, Hugh-George Patterton, Mathabatha Evodia Setati, Katherine A. Borkovich
PLOS ONE.2025; 20(1): e0316713. CrossRef - Macrogenomic and physicochemical analyses reveal microbial community and functional differences among traditional, commercial, and fortified Xiaoqu
Shaoji Zhang, Yao Lin, Tianxiang Wu, Dandan Yuan, Shoufa Jiang, Ping Fu, Wenqiang Nie
Food Bioscience.2025; 68: 106736. CrossRef - In silico evaluation of the potential allergenicity of a fungal biomass from Rhizomucor pusillus for use as a novel food ingredient
Kevin Scaife, Steve L. Taylor, Lucie Pařenicová, Richard E. Goodman, Trung D. Vo, Elisa Leune, Mohamed Abdelmoteleb, Yvonne Dommels
Regulatory Toxicology and Pharmacology.2024; 150: 105629. CrossRef - Human Health Benefits and Microbial Consortium of Stevia Fermented with Barley Nuruk
Hyun-Ju Han, Min Nyeong Ko, Chan Seong Shin, Chang-Gu Hyun
Fermentation.2024; 10(7): 330. CrossRef - Stabilization of jiuyao quality for huangjiu brewing by fortifying functional strains based on core microbial community analysis
Ying Zhu, Shuangping Liu, Donglin Ma, Yuezheng Xu, Chen Yang, Jian Mao
Food Bioscience.2023; 52: 102370. CrossRef - In silico and in vitro safety assessment of a fungal biomass from Rhizomucor pusillus for use as a novel food ingredient
Kevin Scaife, Trung D. Vo, Yvonne Dommels, Elisa Leune, Kaj Albermann, Lucie Pařenicová
Food and Chemical Toxicology.2023; 179: 113972. CrossRef - Effects of saccharification agents on the microbial and metabolic profiles of Korean rice wine (makgeolli)
Jeongmin Cha, Seong-Eun Park, Eun-Ju Kim, Seung-Ho Seo, Kwang-Moon Cho, Sun Jae Kwon, Mee-Hyun Lee, Hong-Seok Son
Food Research International.2023; 172: 113367. CrossRef - Unraveling multifunction of low-temperature Daqu in simultaneous saccharification and fermentation of Chinese light aroma type liquor
Yifu Zheng, Feng Liang, Yi Wu, Shibo Ban, Heqiang Huang, Yan Xu, Xuliang Wang, Qun Wu
International Journal of Food Microbiology.2023; 397: 110202. CrossRef - Genomic and functional features of yeast species in Korean traditional fermented alcoholic beverage and soybean products
Da Min Jeong, Hyeon Jin Kim, Min-Seung Jeon, Su Jin Yoo, Hye Yun Moon, Eun-joo Jeon, Che Ok Jeon, Seong-il Eyun, Hyun Ah Kang
FEMS Yeast Research.2023;[Epub] CrossRef - Enzymatic Hydrolysis of Tenebrio molitor (Mealworm) Using Nuruk Extract Concentrate and an Evaluation of Its Nutritional, Functional, and Sensory Properties
Legesse Shiferaw Chewaka, Chan Soon Park, Youn-Soo Cha, Kebede Taye Desta, Bo-Ram Park
Foods.2023; 12(11): 2188. CrossRef - The differences in carbohydrate utilization ability between six rounds of Sauce-flavor Daqu
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Nitesh Boro, Diganta Narzary
Frontiers in Sustainable Food Systems.2022;[Epub] CrossRef - Enzyme activity of Aspergillus section Nigri strains isolated from the Korean fermentation starter, nuruk
Eunji Jeong, Jeong-Ah Seo
Journal of Microbiology.2022; 60(10): 998. CrossRef - Probiotic properties of lactic acid bacteria isolated from traditionally prepared dry starters of the Eastern Himalayas
Pooja Pradhan, Jyoti Prakash Tamang
World Journal of Microbiology and Biotechnology.2021;[Epub] CrossRef - Fermentation profiling of rice wine produced by Aspergillus oryzae KSS2 and Rhizopus oryzae KJJ39 newly isolated from Korean fermentation starter
Minjoo Kim, Jeong-Ah Seo
Applied Biological Chemistry.2021;[Epub] CrossRef - Integrated genomic and transcriptomic analysis reveals unique mechanisms for high osmotolerance and halotolerance in Hyphopichia yeast
Dong Wook Lee, Chang Pyo Hong, Eun Jung Thak, Sin‐Gi Park, Choong Hwan Lee, Jae Yun Lim, Jeong‐Ah Seo, Hyun Ah Kang
Environmental Microbiology.2021; 23(7): 3499. CrossRef - pH Changes Have a Profound Effect on Gene Expression, Hydrolytic Enzyme Production, and Dimorphism in Saccharomycopsis fibuligera
Mohamed El-Agamy Farh, Najib Abdellaoui, Jeong-Ah Seo
Frontiers in Microbiology.2021;[Epub] CrossRef - Saccharomycopsis fibuligera in liquor production: A review
Zai-Bin Xie, Kai-Zheng Zhang, Zhen-Hui Kang, Jian-Gang Yang
European Food Research and Technology.2021; 247(7): 1569. CrossRef - Diversity of Filamentous Fungi Isolated From Some Amylase and Alcohol-Producing Starters of India
Anu Anupma, Jyoti Prakash Tamang
Frontiers in Microbiology.2020;[Epub] CrossRef - Isolation and Identification of Fungi with Glucoamylase Activity from Loog-pang-khao-mak (A Thai Traditional Fermentation Starter)
Nawaphorn Roongrojmongkhon, Nattawut Rungjindamai, Tipachai Vatanavicharn, Duangjai Ochaikul
Journal of Pure and Applied Microbiology.2020; 14(1): 233. CrossRef - Natural Occurrence of Aflatoxigenic Aspergillus Species and Aflatoxins in Traditional Korean Fermentation Starters, Meju and Nuruk
So Young Woo, Sang Yoo Lee, Fei Tian, A-Yeong Jeong, Cha Nee Yoo, Seung Yoon Kang, Hyang Sook Chun
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International Journal of Food Properties.2019; 22(1): 1205. CrossRef - A script for initiating molecular biology studies with non-conventional yeasts based on Saccharomycopsis schoenii
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Microbiological Research.2019; 229: 126342. CrossRef - Designation of rice cake starters for fermented rice products with desired characteristics and fast fermentation
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Journal of Food Science and Technology.2019; 56(6): 3014. CrossRef - Overexpression of RAD51 Enables PCR-Based Gene Targeting in Lager Yeast
Beatrice Bernardi, Yeseren Kayacan, Madina Akan, Jürgen Wendland
Microorganisms.2019; 7(7): 192. CrossRef - Expansion of a Telomeric FLO/ALS-Like Sequence Gene Family in Saccharomycopsis fermentans
Beatrice Bernardi, Yeseren Kayacan, Jürgen Wendland
Frontiers in Genetics.2018;[Epub] CrossRef - Comparison of volatile and non-volatile metabolites in rice wine fermented by Koji inoculated with Saccharomycopsis fibuligera and Aspergillus oryzae
Eun Yeong Son, Sang Mi Lee, Minjoo Kim, Jeong-Ah Seo, Young-Suk Kim
Food Research International.2018; 109: 596. CrossRef - Bioformation of Volatile and Nonvolatile Metabolites by Saccharomycopsis fibuligera KJJ81 Cultivated under Different Conditions—Carbon Sources and Cultivation Times
Sang Mi Lee, Ji Hye Jung, Jeong-Ah Seo, Young-Suk Kim
Molecules.2018; 23(11): 2762. CrossRef