A Localized Phage-Based Antimicrobial System: Effect of Alginate on Phage Desorption from ß-TCP Ceramic Bone Substitutes.

Tricalcium phosphate (TCP) is a prosthetic material commonly used as a bone substitute to repair osteoarticular diseases and injuries. In this type of bone reconstruction surgery, antibiotics remain the common preventive and therapeutic treatment for bacterial infection. Nevertheless, the emergence of multi-resistant strains requires complimentary or alternative treatments. Today, one of the promising alternative approaches is phage therapy. Phages are bacterial viruses that have several advantages over chemotherapy, such as the specificity of bacterial strain, the absence of side effects, and a rapid response. In this work, we studied the impact of alginate hydrogels for overlaying λvir-phage-loaded ß-TCP ceramic bone substitutes, delaying the phage desorption. The results show that the use of a 1% alginate-CaCl2 hydrogel overlapping the ß-TCP ceramic pellets leads to higher initial phage concentration on the material and extends the released time of phages to two weeks when compared with control pellets. These alginate-coated biomaterials also generate faster bacterial lysis kinetics and could therefore be a good practical prosthetic device for bone and joint surgeries by allowing local treatment of bacterial infections with phage therapy for a longer period of time.

Microbial Safety of Wood in Contact with Food: A Review.

Food packaging is multifunctional: it protects from harvest to table. Four main groups of materials for direct food contact are mentioned in the literature: wood, glass, plastic, and metal. In this review, the focus is on wooden packaging for direct contact with food. In Europe, wood as a food contact material is subject to European Regulation (EC) No 1935/2004 states that materials must not transfer their constituents to food. Today, wooden packaging, like other packaging materials, does not have a Europe-wide harmonized specific regulation, so member countries legislate at different levels. Wood has been safely used for centuries in contact with food but is usually questioned because of its microbiological behavior compared with smooth surfaces. Based on a review of published conclusions from scientific studies over the last 20 y and after a description of the general properties of wooden packaging, we focus on the microbiological status of natural wood. Then, we discuss the parameters influencing the survival of microorganisms on wood. Finally, we report on the transfer of microorganisms from wood to food and the factors influencing this phenomenon. This review demonstrates that the porous nature of wood, especially when compared with smooth surfaces, is not responsible for the limited hygiene of the material used in the food industry and that it may even be an advantage for its microbiological status. In fact, its rough or porous surface often generates unfavorable conditions for microorganisms. In addition, wood has the particular characteristic of producing antimicrobial components able to inhibit or limit the growth of pathogenic microorganisms.

Methods for recovering microorganisms from solid surfaces used in the food industry: a review of the literature.

Various types of surfaces are used today in the food industry, such as plastic, stainless steel, glass, and wood. These surfaces are subject to contamination by microorganisms responsible for the cross-contamination of food by contact with working surfaces. The HACCP-based processes are now widely used for the control of microbial hazards to prevent food safety issues. This preventive approach has resulted in the use of microbiological analyses of surfaces as one of the tools to control the hygiene of products. A method of recovering microorganisms from different solid surfaces is necessary as a means of health prevention. No regulation exists for surface microbial contamination, but food companies tend to establish technical specifications to add value to their products and limit contamination risks. The aim of this review is to present the most frequently used methods: swabbing, friction or scrubbing, printing, rinsing or immersion, sonication and scraping or grinding and describe their advantages and drawbacks. The choice of the recovery method has to be suitable for the type and size of the surface tested for microbiological analysis. Today, quick and cheap methods have to be standardized and especially easy to perform in the field.