Antimicrobial activityoflysozy me with special relevance to milk

Introduction

Milk is a complex medium containing a variety of nutrients,minerals,vitamins as well as other molecules of functionnal or bioactive properties .Inparticular, milk is rich in proteins that are classically grouped into two main classes:(i) major milk proteins including caseins (a,b and κ-caseins) and two whey proteins (i.e.,-lactalbumin and-lactoglobulin),and(ii) minor milk proteins including lysozyme,lactoferrins,lactoperoxidase and immunoglobulins. Although the constituents represent only a minor fraction of milk proteins,they play an important role as first line defense due to their direct and indirect antimicrobial activity (Lonnerdal,2004; Séverin and Wenshui,2005;León-Sicairosetal.,2006) in addition to other important physiological and health promoting functions (Gorbenkoetal.,2007).Lysozyme is among the minor milk proteins that has attracted increased attention recently due to its potentant imicrobial activity against a wide range of microorga-nisms and hence potential in food preservation and safety.This review will focus on the antimicrobial activity of lysozyme with special reference to the milk of different mammals.The mechanisms of action and resistance of/to lysozyme will also bediscussed.