title: Fed-batch pediocin production by Pediococcus acidilactici NRRL B-5627 on whey.
abstract: Cell growth and pediocin production by Pediococcus acidilactici NRRL B-5627 on whey were compared by using batch fermentation and re-alkalized fed-batch fermentation. The batch fermentations were performed on DWG [DW (diluted whey) supplemented with 1% (w/v) glucose], DWYE [DW supplemented with 2% (w/v) yeast extract] and DWGYE (DW supplemented with 1% glucose plus 2% yeast extract) media. The fed-batch culture on DWYE medium was fed with a mixture of concentrated whey (48 g of total sugars/l) supplemented with 2% yeast extract and 400 g/l concentrated glucose. The re-alkalized fed-batch culture was characterized by higher biomass (6.57 g/l) and pediocin [517.6 BU (bacteriocin activity units)/ml] concentrations compared with the batch processes on MRS (de Man, Rogosa and Sharpe) broth (1.76 g/l and 493.2 BU/ml), DW (0.17 g/l and 57.7 BU/ml), DWG (0.14 g/l and 53.6 BU/ml), DWYE (1.43 g/l and 187.6 BU/ml) and DWGYE (1.28 g/l and 167.3 BU/ml) media. A mixed acid fermentation was observed during the growth of P. acidilactici NRRL B-5627 in the fed-batch culture on DWYE medium, and other products (acetic acid and ethanol) in addition to lactic acid accumulated in the medium. Mathematical models were set up to describe fed-batch production of biomass and pediocin by P. acidilactici. The models developed offer a better fit and a more realistic description of the experimental biomass and pediocin production data when compared with the logistic and Luedeking and Piret model.
authors.affiliation: Departamento de Bioquímica, Xenética e Inmunoloxía, Facultade de Ciencias de Ourense, Universidade de Vigo, As Lagoas, 32004 Ourense, Spain.
authors.forename: Nelson
authors.initials: N
authors.lastname: Pérez Guerra
authors.forename: Paula Fajardo
authors.initials: PF
authors.lastname: Bernárdez
authors.forename: Ana Torrado
authors.initials: AT
authors.lastname: Agrasar
authors.forename: Cristina
authors.initials: C
authors.lastname: López Macías
authors.forename: Lorenzo Pastrana
authors.initials: LP
authors.lastname: Castro
mesh_terms: D000818:Animals; D001430:Bacteriocins / Q000096:biosynthesis*; D019149:Bioreactors / Q000382:microbiology*; D018929:Cell Culture Techniques / Q000379:methods*; D049109:Cell Proliferation; D008892:Milk / Q000378:metabolism*; D010376:Pediococcus / Q000254:growth & development* / Q000378:metabolism*
chemical_list: D001430:Bacteriocins