ANTIBACTERIAL REACTIVE LIPOSOMES ENCAPSULATING COUPLED ENZYME-SYSTEMS

Liposomes have been prepared from phospholipid mixtures of dipalmitoyl phosphatidylcholine (DPPC) and phosphatidylinositol (PI) encapsulating the enzymes chloroperoxidase (CPO) and lactoperoxidase (LPO) in combi nation with glucose oxidase (GO) by both extrusion (VET) and/or revers e phase evaporation (REV). The liposomes were characterised in terms o f the protein content and activity of the encapsulated enzymes. The an tibacterial activity of these reactive liposomes arises from hydrogen peroxide and oxyacids produced in the presence of the substrates gluco se and chloride or thiocyanate ions. The liposomes were targeted to bi ofilms of Steptococcus gordonii, an oral bacterium and their antibacte rial activity was measured both as a function of liposome-biofilm incu bation time and incubation time with the substrates. Bacterial inhibit ion increases with both liposome-biofilm and substrate-biofilm incubat ion time and with the extent of enzyme encapsulation. The reactive lip osomes also display antibacterial activity in the presence of saliva. The reactive liposomes have potential value in the context of oral hyg iene. (C) 1998 Elsevier Science B.V. All rights reserved.