Use of grape pomaces to produce biomass of aKomagataella pastoris strain expressing a bovine chymosin activity

• Published in: Food science & nutrition Vol. 2; no. 6; pp. 734 - 743
• Main Authors: Kingston, Diego, Novelli, Guido F, Cerrutti, Patricia, Recupero, Matias N, Blasco, Martin, Galvagno, Miguel A
• Format: Journal Article
• Language: English
• Published: United States BlackWell Publishing Ltd 01-11-2014
• Subjects: Original Research; Agroindustrial by-product; Komagataella pastoris biomass; bovine chymosin
• ISSN: 2048-7177; 2048-7177
• DOI: 10.1002/fsn3.128

The use of agroindustrial wastes not only decreases bioprocesses and disposal costs but also contributes to the upgrading of the residues. An active recombinant methanol-inducible bovine chymosin has been expressed in our laboratory in the yeastKomagataella pastoris, and grape pomace extracts (GRE) were proposed as a convenient C-energy source for the biomass production of the genetically engineered strain. Carbon and nitrogen sources, growth factors, and initial pH conditions were selected by classical methodology; thereafter, growth conditions optimization was performed using statistical designed experiments (DoEs). In the presence of (in g·L(-1)) 67.0 monosaccharides (glucose and fructose) from GRE, 5.0 (NH4)2SO4, and 10.0 sugar cane molasses (CMz), a yield of 20.0 g·L(-1) cell dry weight (CDW) was obtained aerobically after 60 h incubation at 28°C and pH 4.0. Applying a fed-batch strategy with methanol:sorbitol as the enzyme inducers, a chymosin production of 8.53 International Milk Clotting Units (IMCU) per mg protein was obtained in the supernatant. The results presented show that through a statistical design, a simple, cheap, and easy to prepare culture medium could be developed using two agroindustrial derivatives (GRE and CMz) to obtain a higher value added product.