Nisin Peptide as Promising Natural Food Preservative for Food

Sodium  Nitrite  has  been  widely  use  as  preservative  for  meats  and  fish  Products, but  in recent  years  there  has  been  considerable  interest  for  searching  about  natural  Food  preservatives  like  Nisin  peptide. The  aim  of  this  study  was  to  compare  the  inhibitory  effect  of  two preservatives  were  Sodium  Nitrite  and  Nisin  peptide  separately  against  Staphylococcus  Aureus  (Staph. A),  Escherichia  coli (E. coli),  and  Candida  Albicans  (C. Albicans)  in  Mueller Hinton  Broth  (MHB)  at  three  different  pH  (7.0- 6.0- 5.5).  After  that  the  combination  effect  between  Sodium  Nitrite  and  Nisin  was  studied  in  MHB  at  optimum  pH  that  was  concluded from  the  previous  stage. Minimal  Inhibitory  Concentrations  (MIC)  and  Minimal  Bactericidal Concentrations  (MBC)  of  both  preservatives  were  evaluated. FIC values (Fractional Inhibitory Concentration) were calculated   after combination between them. The  results  showed  that  MIC  values  of  Sodium  Nitrite  against  S. Aureus,  E. coli  and  C. albicans  at  pH 5.5  were  (500- 200- 500)  ppm  respectively  and   MIC  values  of  Nisin  were (100- 350- 500)  ppm respectively, while  MIC  values  of  the  combination  (Sodium  Nitrite+ Nisin)  against  S. A, E. coli  and  C. albicans were  (50- 25- 100)  ppm  respectively  and  FIC  values of  them  were  (0.39- 0.15- 0.30).  On  the  other  hand  The  results  showed  that  simultaneous  use  of  Nisin  with  sodium  nitrite  reduced  MIC  and  MBC  of  this  compound  against  bacteria and  fungi  Significantly  consequently, this  synergistic  effect  of  Nisin  could  promote  in  the  Future   to  reduce  of  the  using  of  Sodium  Nitrite  in  food  industry.

Keywords: Bacteria, FIC., MIC, Nisin, Synergism