title: Nisin production from Lactococcus lactis A.T.C.C. 7962 using supplemented whey permeate.
abstract: The influence of pH control and aeration (20% dissolved oxygen) on nisin production in a supplemented cheese whey permeate was examined during batch fermentation with Lactococcus lactis subsp. lactis A.T.C.C. 7962. A maximum nisin activity of 5280 i.u./ml of medium was observed in the raw extract of nisin after 9 h of fermentation with a constant pH at 4.9. However, the fermentation was continued until 24 h, when a decrease in the nisin activity was observed. The pH control did not influence the nisin production and aeration of the culture medium increased cell growth (biomass) but not nisin activity. The yeast Kluyveromyces marxianus, used as an alternative method to control pH, has not been efficient.
authors.affiliation: Departamento de Engenharia de Alimentos, Faculdade de Engenharia de Alimentos, UNICAMP, Caixa Postal 6121, Campinas, SP, Brasil, CEP: 13083-970.
authors.forename: S H
authors.initials: SH
authors.lastname: Flôres
authors.forename: R M
authors.initials: RM
authors.lastname: Alegre
mesh_terms: D000818:Animals; D018533:Biomass; D002417:Cattle; D002611:Cheese; D003470:Culture Media; D029968:Escherichia coli Proteins; D005285:Fermentation; D006863:Hydrogen-Ion Concentration; D013294:Lactococcus lactis / Q000254:growth & development / Q000378:metabolism*; D026901:Membrane Transport Proteins / Q000378:metabolism; D008894:Milk Proteins / Q000378:metabolism*; D009004:Monosaccharide Transport Proteins; D009561:Nisin / Q000096:biosynthesis* / Q000378:metabolism; D027981:Symporters; D000067816:Whey Proteins
chemical_list: D003470:Culture Media; D029968:Escherichia coli Proteins; C050221:LacY protein, E coli; D026901:Membrane Transport Proteins; D008894:Milk Proteins; D009004:Monosaccharide Transport Proteins; D027981:Symporters; D000067816:Whey Proteins; D009561:Nisin; C021499:lactose permease