From beta-cyclodextrin polyelectrolyte to layer-by-layer self-assembly microcapsules: from inhibition of bacterial growth to bactericidal effect

Publication date: Available online 19 April 2019Source: Food HydrocolloidsAuthor(s): Sabrina Belbekhouche, Noureddine Bousserrhine, Vanessa Alphonse, Benjamin CarbonnierAbstractPathogenic bacteria resistance to antimicrobial agents has emerged as a major health issue. Developing new systems enabling inhibitory and bactericidal effects is crucial. Herein, layer-by-layer technique (LbL) was used to fabricate microcapsules composed of biopolymers, cationic polycyclodextrin (P(CD+)) and anionic alginate (alg-). This was achieved through successive adsorption of these polyelectrolytes onto calcium carbonate microparticles (CaCO3) used as template. Then, a chelating agent was added for removing the CaCO3 core, leading to microcapsules. Quartz crystal microbalance and zeta potential measurements evidenced the successful alternate adsorption of polyelectrolytes and related charge reversal, respectively, upon the LbL deposition. The shape of the capsules was characterized by Scanning Electron Microscopy (SEM) and fluorescence microscopy. The antibacterial activity of P(CD+) was first evidenced on two well-known bacteria: Staphylococcus aureus (Gram-positive) and Escherichia coli (Gram-negative) using well diffusion method on Plate Count Agar (PCA) medium. Then, an inhibitory effect on the bacteria growth has been observed for the P(CD+)-based microcapsules during bacterial culture in Luria-Bertani (LB) broth medium. Our results pointed out towards a strong dependence of the extent of ...
Source: Food Hydrocolloids - Category: Food Science Source Type: research