Produção de compósitos de celulose bacteriana de chás fermentados (kombucha) e nanopartículas de prata obtidas por extrato vegetal de guaraná (Paullinia cupana)

Abstract

Silver nanoparticles (AgNPs) are a promising material for biomedical applications due to their antibacterial, antifungal and antiviral properties. With the growing environmental concerns, a new synthesis method based on more environmentally friendly technologies has emerged, such as green synthesis, which generally uses plants that present secondary metabolites capable of reducing Ag+ ions. AgNPs have been widely used in polymeric materials with the aim of enhancing their use in implants in the human body, reducing the chances of contamination and microbial colonization after implantation, particularly bacterial cellulose (BC), which can be cultivated through a tea called kombucha. The present study aims to produce and characterize the produced AgNPs, to produce and characterize the BC membranes obtained through kombucha and analyze the interaction between both materials to create an organic/inorganic hybrid material with potential microbicidal effect. The characterization of BC showed that the material has high purity and crystallinity, confirming it as bacterial cellulose by the XRD technique. The guarana plant extract exhibited a good reducing capacityt for the formation of AgNPs, as confirmed by the yellowish coloration and by the UV-Vis spectroscopy technique. The formation of the hybrid material was confirmed by the change in the coloration of the material, by the UV-Vis spectroscopy technique, and by the change in the coloration of the reaction medium.