title: Nisin production of Lactococcus lactis N8 with hemin-stimulated cell respiration in fed-batch fermentation system.
abstract: In this study, nisin production of Lactococcus lactis N8 was optimized by independent variables of glucose, hemin and oxygen concentrations in fed-batch fermentation in which respiration of cells was stimulated with hemin. Response surface model was able to explain the changes of the nisin production of L. lactis N8 in fed-batch fermentation system with high fidelity (R(2) 98%) and insignificant lack of fit. Accordingly, the equation developed indicated the optimum parameters for glucose, hemin, and dissolved oxygen were 8 g L(-1) h(-1) , 3 μg mL(-1) and 40%, respectively. While 1711 IU mL(-1) nisin was produced by L. lactis N8 in control fed-batch fermentation, 5410 IU mL(-1) nisin production was achieved within the relevant optimum parameters where the respiration of cell was stimulated with hemin. Accordingly, nisin production was enhanced 3.1 fold in fed-batch fermentation using hemin. In conclusion the nisin production of L. lactis N8 was enhanced extensively as a result of increasing the biomass by stimulating the cell respiration with adding the hemin in the fed-batch fermentation.
authors.affiliation: Dept. of Food Engineering, University of Pamukkale, Denizli, Turkey.
authors.forename: Burcu
authors.initials: B
authors.lastname: Kördikanlıoğlu
authors.affiliation: Dept. of Food Engineering, University of Pamukkale, Denizli, Turkey.
authors.forename: Ömer
authors.initials: Ö
authors.lastname: Şimşek
authors.affiliation: Dept. of Food and Environmental Sciences, University of Helsinki, Helsinki, Finland.
authors.forename: Per E J
authors.initials: PE
authors.lastname: Saris
mesh_terms: D019342:Acetic Acid / Q000378:metabolism; D018533:Biomass; D003470:Culture Media / Q000737:chemistry; D005285:Fermentation; D005947:Glucose / Q000737:chemistry; D006427:Hemin / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D019344:Lactic Acid / Q000378:metabolism; D013294:Lactococcus lactis / Q000378:metabolism*; D016982:Micrococcus luteus / Q000378:metabolism; D009561:Nisin / Q000096:biosynthesis*; D010100:Oxygen / Q000737:chemistry
chemical_list: D003470:Culture Media; D009561:Nisin; D019344:Lactic Acid; D006427:Hemin; C102526:nisin A; D005947:Glucose; D019342:Acetic Acid; D010100:Oxygen
keywords: L. lactis; fed-batch fermentation; hemin; nisin; respiration