| Congresso Brasileiro de Microbiologia 2023 | Resumo: 1127-1 | ||||
Resumo:Chitosan is obtained through the deacetylation of chitin, which in turn can be extracted from naturally-chitin containing materials such as shrimp wastes, fungal cell walls and insect exoskeletons. Chitosan is a polymer with applications in different areas and has antimicrobial properties. In this work, the chitosan production process was optimized using lactic fermentation by Lactiplantibacillus plantarum in sugarcane molasses medium with shrimp wastes to obtain chitin followed by chemical deacetylation, whose conditions were also optimized. The resulting chitosan was characterized and tested against a bacterium that contaminates the ethanolic fermentation process, Limosilactobacillus fermentum, and against an industrial yeast of Saccharomyces cerevisiae to verify its antimicrobial action. Additionally, chitosan microspheres were obtained and tested as carriers of antimicrobial substances. The main objective here is to evaluate chitosan as antimicrobial in the context of ethanolic fermentation to replace sulfuric acid in the cell treatment step between fermentation cycles. In the context of food industry, chitosan films were also produced for special coffee packaging evaluating physical, microbiological and sensory attributes. With chitosan, after 3 h of cell treatment, the population of L. fermentum was reduced significantly and similarly to the result obtained with sulfuric acid. The effect on the yeast is negligible. Fermentation assays (fed-batch with cell recycle) confirmed the antibacterial effect of chitosan utilized in the cell treatment. Chitosan microspheres did not present antibacterial effect but have interesting characteristics for use in the encapsulation of substances such as antibiotics and essential oils. Chitosan conferred greater mechanical resistance to coffee packaging and contributed to better sensory attributes.
Supporting agencies: FAPESP, CNPq and CAPES
Palavras-chave: chitosan, antimicrobial, fermentation, bioethanol, food Agência de fomento:Fapesp, CNPq, Capes | |||||