Gonzalo Serafica

Environmental implications of microbial cellulose

Abstract The strong, tough, highly pure cellulose synthesized by microorganisms is just emerging as a new industrial product with exciting new applications in medicine, in foods, and in paper and packaging as well as potential for use in industrial separations. Making a polymer by bioprocessing is inherently much less damaging to the environment than are petrochemical processes, and this cellulose may substitute for plastics and for special grades of paper. This would eliminate some petrochemical processing and the highly pollutional steps for pulping and bleaching of wood cellulose. Wastes that contain cellulose can be converted to sugars that are substrates for the microorganisms that make cellulose. Microbial cellulose produced rapidly by Acetobacter xylinium in a rotating disk reactor is a gel with 100 to 200 parts of water per part of cellulose. Much of the water can be removed mechanically so that little drying is needed to get a product resembling parchment in its appearance and properties. Small amounts of microbial cellulose added to paper greatly improve its strength. This new cellulose may compete well with existing polymers and paper on its own merits, and environmental benefits may make the cost comparisons even more favorable.