Avaliação Da Atividade Antibacteriana De Filmes De Hidroxipropilmetilcelulose A Base De Goma Do Cajueiro Quaternizada

Abstract

Introduction: Polysaccharides are polymers composed of glycosidic bonds with high molecular weight and presence of biological activities. Cashew Gum (CG), extracted from the species Anacardium occidentale L., is composed mainly of galactose and has antimicrobial properties. The growth of the bacterial resistance profile awakens the need to search for new antimicrobial agents and applications of these compounds in the biomedical area. Thus, hydropropylmethyl cellulose (HPMC) appears as an alternative for applications of polysaccharides, whose biological functions were enhanced by chemical modification. The objective of the study is to produce HPMC and CG films, characterize them and evaluate the antimicrobial activity. Methodology: To obtain Cashew Gum, collection, purification and drying were carried out. Then, it was chemically modified by the quaternization process, using CHPTAC, resulting in Quaternized Cashew Gum (QCG). The natural and modified polysaccharides were

characterized by FTIR and Zeta Potential analysis. The production of HPMC and GCQ- HPMC films was carried out by the casting method, followed by characterization of the

films by thickness and transparency, water absorption and moisture content. The antimicrobial activity was evaluated by the agar diffusion method against Staphylococcus spp. and Escherichia coli. Results: The characterization of quaternized cashew gum (GCQ) evidenced quaternization by FTIR analysis, which confirmed the presence of specific bands, and by the change in Zeta potential, reflecting the chemical changes. The polymeric films containing GCQ presented greater thickness (0.0321 mm) and lower transparency (2.119 A600/mm) compared to pure HPMC films, in addition to demonstrating greater moisture retention and water absorption capacity, due to the hydrophilic properties of the polysaccharide. Regarding antimicrobial activity, pure HPMC films showed no inhibitory effect, while films containing HPMC + GCQ exhibited significant inhibition zones against Staphylococcus aureus and Staphylococcus epidermidis (10-12 mm). Conclusion: It is concluded that HPMC films with quaternized GC have superior physical properties and effective antimicrobial activity, highlighting the biomedical potential of this combination. The study demonstrates the positive impact of chemical modification on the functionality of biopolymers, with promising applications in fighting infections.