Obtaining extracts rich in antioxidant polysaccharides from the edible mushroom Pleurotus ostreatus using binary system with hot water and supercritical CO2.

Pleurotus ostreatus is an edible mushroom with pharmacological potential, due to its metabolites, mainly polysaccharides. On here, the development of a new methodology for the recovery of extract rich in antioxidant polysaccharide was reported. The extracts were characterized, evaluated for antioxidant activity in vitro and in cell models and cytotoxicity. The best defined extraction condition was 25 MPa, 433.15 K, and 20% H2O, with 30.69% of the total yield and 0.921 mg of CHO3. The anomeric bonds, identified in the FTIR and NMR spectrum, indicate that the extracts are a mixture of heteropolysaccharides, ß-glucans, α-glucans, and oligosaccharides. The best extraction condition has 80.83% of antioxidant activity, without cytotoxic effect in vitro. In addition to antioxidant activity in cell model, increasing protection against oxidative damage induced by H2O2. Finally, H2O + CO2-SFE technology can be used to obtain extracts rich in antioxidant polysaccharides with pharmacological and food potential.

Improvement of the characteristics of fish gelatin - gum arabic through the formation of the polyelectrolyte complex.

The aim of this study was to evaluate and characterize the interaction between fish gelatin (FG) and Gum Arabic(GA) and its effects in obtaining optimal atomization conditions. The optimal conditions (D = 0.866) founded in this paper were: Gum Arabic concentration of 33.4% and inlet air temperature of 130 °C. These conditions afforded 6.62 g/h yield, 0.27 aw and 247 g of Gel Strength, that are considered as suitable characteristics for food grade gelatin. The complex formed (FG-GA) was successfully obtained, as demonstrated by the results of amino acid profile, SDS-PAGE, FTIR spectroscopy, zeta potential and morphology. It was also verified that the formation of FG-GA promotes positive changes, such as higher atomization yield, adequate Gel Strength, low hygroscopicity and high solubility. The technological properties of FG-GA shown high potential to be applied in the food industry as well in other industrial fields like chemical and pharmaceutical areas.