A method for bacteriocin quantification

Different aspects of the most commonly used assay methods in the study of b acteriocins were examined. The conditions under which extraction and incuba tion (including exposure time) take place were analysed, and several differ ent formal models that are usually employed to calculate ID50 were compared . As an alternative designed to overcome the problems which characterize th e response of micro-organisms that are sensitive to bacteriocins, an operat ive procedure in a liquid medium and a modified re-parameterized logistic e quation is proposed. When applied to the inhibition of Leuconostoc mesenter oides by nisin, the model allows an optimal experimental procedure to be de fined.