RESUMO
In order to enable the applicability of chitosan as an antifungal, soil fungi were isolated and identified, then used in its production. Fungal chitosan has several advantages, including lower toxicity, low cost, and high degree of deacetylation. These characteristics are essential for therapeutic applications. The results indicate high viability of the isolated strains to produce chitosan, obtaining a maximum yield of 40.59 mg chitosan/g of dry biomass. M. pseudolusitanicus L. was reported for the first time for production by chitosan. The chitosan signals were observed by ATR-FTIR and 13C SSNMR. Chitosans showed high degrees of deacetylation (DD), ranging from 68.8% to 88.5%. In comparison with the crustacean chitosan, Rhizopus stolonifer and Cunninghamella elegans presented lower viscometric molar masses (26.23 and 22.18 kDa). At the same time, the molar mass of chitosan Mucor pseudolusitanicus L. showed a value coincident with that assumed as low molar mass (50,000-150,000 g mol-1). Concerning the in vitro antifungal potential against the dermatophyte fungus Microsporum canis (CFP 00098), the fungal chitosans showed satisfactory antifungal activities, inhibiting mycelial growth by up to 62.81%. This study points to the potential of chitosans extracted from fungal cell walls for applications in the inhibition of the growth of (Microsporum canis) human pathogenic dermatophyte.
Assuntos
Quitosana , Humanos , Quitosana/química , Antifúngicos/farmacologia , Fungos , Microsporum , Peso MolecularRESUMO
Oxidative stress is the cause of numerous diseases in humans; therefore, there has been a continuous search for novel antioxidant molecules. Fungal chitosan is an attractive molecule that has several applications (antifungal, antibacterial, anticancer and antiparasitic action) owing to its unique characteristics; however, it exhibits low antioxidant activity. The aim of this study was to obtain fungal chitosan (Chit-F) from the fungus Rhizopus arrhizus and synthesize its derivative, fungal chitosan-gallic acid (Chit-FGal), as a novel antioxidant chitosan derivative for biomedical use. A low molecular weight Chi-F (~3.0 kDa) with a degree of deacetylation of 86% was obtained from this fungus. Chit-FGal (3.0 kDa) was synthesized by an efficient free radical-mediated method using hydrogen peroxide (H2O2) and ascorbic acid. Both Chit-F and Chit-FGal showed similar copper chelating activities; however, Chit-FGal was more efficient as an antioxidant, exhibiting twice the total antioxidant capacity than Chi-F (p < 0.05). Furthermore, H2O2 (0.06 M) promoted a 50% decrease in the viabilities of the 3T3 fibroblast cells. However, this effect was abolished in the presence of Chit-FGal (0.05-0.25 mg/mL), indicating that Chit-FGal protected the cells from oxidative damage. These results suggest that Chit-FGal may be a promising agent to combat oxidative stress.
RESUMO
In this work, we propose the reuse of apple pomace as a substrate for fungal chitosan production by liquid cultivation of Gongronella butleri CCT4274. Different concentrations of reducing sugars and sodium nitrate were added to the aqueous extract of apple pomace and the best result was obtained with 40 g/L of reducing sugars and 2.5 g/L of sodium nitrate. The results indicate the possibility of producing 1.19 g/L of chitosan per liter of culture medium after 72.5 hours of cultivation, representing around 21% of the biomass content.
Este trabalho propõe o reuso do bagaço de maçã como substrato para a produção de quitosana fúngica em cultivo liquido do fungo Gongronella butleri CCT4274. Diferentes concentrações de açúcares redutores e nitrato de sódio foram adicionadas ao extrato aquoso do bagaço de maçã. O melhor resultado foi obtido para concentrações de 40 g/L e 2,5 g/L de açúcares redutores e nitrato de sódio, respectivamente. Os resultados indicam a possibilidade de produzir 1,19 g/L de quitosana após 72,5 horas de cultivo, representando 21% da composição da biomassa.
Assuntos
Carboidratos/análise , Malus , Meios de Cultura/análise , Quitosana/análise , Substratos para Tratamento Biológico/análise , Amostras de Alimentos , Métodos , MétodosRESUMO
In this work, we propose the reuse of apple pomace as a substrate for fungal chitosan production by liquid cultivation of Gongronella butleri CCT4274. Different concentrations of reducing sugars and sodium nitrate were added to the aqueous extract of apple pomace and the best result was obtained with 40 g/L of reducing sugars and 2.5 g/L of sodium nitrate. The results indicate the possibility of producing 1.19 g/L of chitosan per liter of culture medium after 72.5 hours of cultivation, representing around 21% of the biomass content.
RESUMO
In this work, we propose the reuse of apple pomace as a substrate for fungal chitosan production by liquid cultivation of Gongronella butleri CCT4274. Different concentrations of reducing sugars and sodium nitrate were added to the aqueous extract of apple pomace and the best result was obtained with 40 g/L of reducing sugars and 2.5 g/L of sodium nitrate. The results indicate the possibility of producing 1.19 g/L of chitosan per liter of culture medium after 72.5 hours of cultivation, representing around 21% of the biomass content.
Este trabalho propõe o reuso do bagaço de maçã como substrato para a produção de quitosana fúngica em cultivo liquido do fungo Gongronella butleri CCT4274. Diferentes concentrações de açúcares redutores e nitrato de sódio foram adicionadas ao extrato aquoso do bagaço de maçã. O melhor resultado foi obtido para concentrações de 40 g/L e 2,5 g/L de açúcares redutores e nitrato de sódio, respectivamente. Os resultados indicam a possibilidade de produzir 1,19 g/L de quitosana após 72,5 horas de cultivo, representando 21% da composição da biomassa.