Nisin produced in-house showed the highest values for purifi-cation factor (PF) 774 for water elution and 384 for PBS elution,3 times higher than PF from commercial nisin it was 268 forwater elution and 135 for PBS elution (Table 1).Differences between nisin formulations might explainthe discrepancy between yield values for the commercialand in-house samples: the commercial one contains sodiumchloride, whereas nisin produced in-house was not sup-plemented with salt. Sodium chloride contributes to lipidoxidation (Ladikos and Lougovois, 1990) and might increase