Metal-loaded porous matrices based on clay and cellulose materials displayed appreciable antibacterial activity against Escherichia coli DH5α and Bacillus subtilis 168. BoltornTMH20 polyol dendrimer supported by montmorillonite and cellulose turned out to be effective porous matrices for Cu0 and Ag0 nanoparticles dispersion. The resulting organoclay and polyol-coated cellulose were found to stabilize Cu0 and Ag0 nanoparticles through their terminal hydroxyl groups. This was explained in terms of Lewis Acid-Base interaction between the electron pair of the oxygen atom belonging to the terminal hydroxyl and metal species as supported by XPS data. The metal retention strength was found to correlate with the antibacterial activity, surface basicity and hydrophilic character. These findings are of great importance, because they open promising prospects for vegetal fibers and clay-supported drugs to treat dermatological and gastro-intestinal infections.