Resumo

Introduction and Objectives Nisin, an antimicrobial peptide, has also potential biomedical applications. Important advances in this field include the use of nisin in the development of antimicrobial packaging and liposome encapsulation. Research has also revealed the potential of nisin as a therapeutic agent, such as in cattle mastitis, human ulcer and topical skin infections. This bacteriocin when impregnated into the membranes of poly(lactic-co-glycolic acid) or PLGA may has a great therapeutic potential for scaffolds applications in skin infections combining two components into a single bioproduct. Materials and Methods The assays were carried out with PLGA membranes immersed in a solution of nisin (PBS buffer/pH 4.5, [nisin] = 250 μg/mL), in sterile microtubes were centrifuged at 1.900xg for 1 minute, stirred and centrifuged again, the process was repeated 5 times. This solution was remained in contact at 30ºC and 150 rpm until completely dry. Subsequently, the nisin effect in PLGA was evaluated in agar-diffusion inhibitory activity assays (in logAU/mL) with L. sakei as a bioindicator. The study of the release of nisin in PLGA membranes was carried out by adding PLGA/nisin in a plate containing the bioindicator, its inhibitory activity was calculated and after this period, the same membrane was added in a second plate, and thus the method was repeated until its inhibitory activity to be equal to 0.0 logAU/mL. Results and Conclusions According to the results, the release of nisin in PLGA membranes occurs gradually after 2 days, there was obtained the highest inhibitory activity, 3.47 logAU/mL, after 4 days the activity has a decrease, 2.32 logAU/mL. The release of nisin followed a tendency of decrease in activity with the increase of time (days/logAU/mL): 6/2.22, 8/1.79, 10/1.23, 12/0.67, 14/0.11, and 16 days/0.0 logAU/mL. The results showed that in these conditions under evaluation, the PLGA can release nisin up to 2 weeks, and with inhibitory activity until the fourteenth day. The complex PLGA/nisin shows up attractive for therapeutic application and has great potential in the medical microbiology field.