
Biotechnology and Applied Biochemistry (2001) 34, (103107) (Printed in Great Britain)
Nisin production from Lactococcus lactis A.T.C.C. 7962 using supplemented whey permeate
Simone Hickmann Flôres and Ranulfo Monte Alegre1
Departamento de Engenharia de Alimentos, Faculdade de Engenharia de Alimentos, UNICAMP, Caixa Postal 6121, Campinas, SP, Brasil, CEP: 13083-970
Key words: bacteriocin, fermentation, LAB, preservative.
Abbreviations used: LAB, lactic acid bacteria; CDW, cell dry weight.
1To whom correspondence should be addressed (e-mail ranulfo@ceres.fea.unicamp.br).
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.
Received 22 May 2001; accepted 25 July 2001
Portland Press Ltd ©
2001
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