| Autor: |
Berger LR; Post-Graduation Program in Biological Sciences, Federal University of Pernambuco, Recife, PE 50670-420, Brazil. quelberger@hotmail.com., Stamford TC; Department of Tropical Medicine, Center of Health Sciences, Federal University of Pernambuco, Recife, PE 50670-420, Brazil. thayzastamford@yahoo.com.br., Stamford-Arnaud TM; Department of Tropical Medicine, Center of Health Sciences, Federal University of Pernambuco, Recife, PE 50670-420, Brazil. thayzastamford@yahoo.com.br., de Alcântara SR; Post-Graduation Program in Development and Environment, Federal University of Paraíba, Campus 1, João Pessoa, PB 58051-900, Brazil. pohlux@gmail.com., da Silva AC; Nucleus of Research in Environmental Science and Biotechnology (NPCIAMB), Catholic University of Pernambuco, Recife, PE 50050-590, Brazil. antoniocardoso2000@yahoo.com.br., da Silva AM; Post-Graduation Program in Biological Sciences, Federal University of Pernambuco, Recife, PE 50670-420, Brazil. antoniocardoso2000@yahoo.com.br., do Nascimento AE; Nucleus of Research in Environmental Science and Biotechnology (NPCIAMB), Catholic University of Pernambuco, Recife, PE 50050-590, Brazil. elesbao@unicap.br., de Campos-Takaki GM; Nucleus of Research in Environmental Science and Biotechnology (NPCIAMB), Catholic University of Pernambuco, Recife, PE 50050-590, Brazil. galba_takaki@yahoo.com.br. |
| Abstrakt: |
This article sets out a method for producing chitin and chitosan by Cunninghamella elegans and Rhizopus arrhizus strains using a green metabolic conversion of agroindustrial wastes (corn steep liquor and molasses). The physicochemical characteristics of the biopolymers and antimicrobial activity are described. Chitin and chitosan were extracted by alkali-acid treatment, and characterized by infrared spectroscopy, viscosity and X-ray diffraction. The effectiveness of chitosan from C. elegans and R. arrhizus in inhibiting the growth of Listeria monocytogenes, Staphylococcus aureus, Pseudomonas aeruginosa, Salmonella enterica, Escherichia coli and Yersinia enterocolitica were evaluated by determining the minimum inhibitory concentrations (MIC) and the minimum bactericidal concentrations (MBC). The highest production of biomass (24.60 g/L), chitin (83.20 mg/g) and chitosan (49.31 mg/g) was obtained by R. arrhizus. Chitin and chitosan from both fungi showed a similar degree of deacetylation, respectively of 25% and 82%, crystallinity indices of 33.80% and 32.80% for chitin, and 20.30% and 17.80% for chitosan. Both chitin and chitosan presented similar viscosimetry of 3.79-3.40 cP and low molecular weight of 5.08×10³ and 4.68×10³ g/mol. They both showed identical MIC and MBC for all bacteria assayed. These results suggest that: agricultural wastes can be produced in an environmentally friendly way; chitin and chitosan can be produced economically; and that chitosan has antimicrobial potential against pathogenic bacteria. |
