title: [Isolation and fermentation condition of milk-clotting enzyme producing strain from glutinous rice wine].
abstract: Glutinous rice wine is a traditional food in south of China and it can coagulate milk. It has been proved that its function of coagulating milk is because of the presence of milk-clotting enzyme produced by microorganisms in glutinous rice wine. The aim of this work is to isolate milk-clotting enzyme producing strain from glutinous rice wine and study the fermentation condition. We screened out four bacteria and fungus by gradient dilution. It was proved that mold played the most important role in the production of milk-clotting enzyme. This is further confirmed by casein plate method. The optimization of fermentation conditions revealed that two times concentrated potato medium supplemented with 5% glucose without additional nitrogen was better for production of the enzyme. The enzyme activity was increased 144% under the conditions established.
authors.affiliation: Tianjin Key Laboratory of Food nutrition & safety, Department of Food Engineering & Biotechnology, Tianjin University of Science & Technology, Tianjin 300457, China.
authors.forename: Qiaoling
authors.initials: Q
authors.lastname: Cheng
authors.forename: Xiaojia
authors.initials: X
authors.lastname: Bai
authors.forename: Yanping
authors.initials: Y
authors.lastname: Wang
mesh_terms: D016282:Aspartic Acid Endopeptidases / Q000096:biosynthesis*; D001419:Bacteria / Q000302:isolation & purification* / Q000378:metabolism; D003470:Culture Media; D005285:Fermentation; D012275:Oryza / Q000378:metabolism; D014920:Wine / Q000382:microbiology*; D015003:Yeasts / Q000166:cytology / Q000302:isolation & purification* / Q000378:metabolism
chemical_list: D003470:Culture Media; D016282:Aspartic Acid Endopeptidases; C022517:rennin-like enzyme (Aspergillus ochraceus)