title: Production and characterization of a milk-clotting protease produced in submerged fermentation by the thermophilic fungus Thermomucor indicae-seudaticae N31.
abstract: Proteases are some of the most important industrial enzymes, and one of their main applications is for the production of cheese in the dairy industry. Due to a shortage of animal rennet, microbial coagulant proteases are being sought. In this work, the production of microbial rennet from Thermomucor indicae-seudaticae N31 was studied in submerged fermentation. The best enzyme production was obtained in a fermentation medium containing 4 % wheat bran as the substrate in 0.3 % saline solution, incubated for 72 h at 45 °C and 150 rpm. The value of the milk clotting activity (MCA) was 60.5 U/mL, and the ratio to proteolytic activity (MCA/PA) was 510. The crude enzyme showed optimum pH at 5.5 and two peaks of optimum temperature (MCA at 65 °C and PA at 60 °C). The MCA was stable in the pH range 4.0-4.5 for 24 h and up to 55 °C for 1 h. It was stable during storage at different temperatures (-20 to 25 °C) for 10 weeks. Based on these results, we conclude that microbial rennet from T. indicae-seudaticae N31 produced by submerged fermentation showed good prospects of replacing traditional rennet.
authors: Laboratory of Biochemistry and Applied Microbiology, São Paulo State University-UNESP, Rua Cristóvão Colombo, 2265, São Jose do Rio Preto, São Paulo, 15054-000, Brazil.
authors: B L
authors: BL
authors: Silva
authors: F M
authors: FM
authors: Geraldes
authors: C S
authors: CS
authors: Murari
authors: E
authors: E
authors: Gomes
authors: R
authors: R
authors: Da-Silva
mesh_terms: D012085:Chymosin / Q000378:metabolism*; D004043:Dietary Fiber; D005285:Fermentation; D007218:Industrial Microbiology / Q000379:methods*; D009090:Mucorales / Q000378:metabolism*; D010447:Peptide Hydrolases / Q000378:metabolism
chemical_list: D004043:Dietary Fiber; C025350:rennet; D010447:Peptide Hydrolases; D012085:Chymosin