Improved antioxidant activity of a starch and gelatin-based biodegradable coating containing Tetradenia riparia extract.

The incorporation of plant-based extracts into polymer-based coatings is an efficient alternative to increase the shelf-life of stored fruit and to decrease or even prevent bacterial growth. Considering strawberries, it is also important to preserve their high antioxidant activity. Hence, this work evaluated the efficiency of a coating based on native cassava starch (NCS), gelatin, and sorbitol, containing different concentrations of Tetradenia riparia extract, in delaying the ripening process of strawberries stored under refrigerated conditions, and in preventing bacterial growth and antioxidant activity losses. Both concentrations of extract (500 or 1000 µg mL-1) increased the thickness, opacity, and water vapor transmission rate (WVTR) of the films when compared to the film without extract, but decreased the solubility. Even though the film without extract was expected to create a more efficient barrier to the coated fruits, the films containing the extract led to similar results of soluble solids (SS), titratable acidity (TA), and vitamin C. Nevertheless, the extract incorporation improved the control over bacterial growth, and preserved the high antioxidant activity of the strawberries within ten days of storage.

Iron Or Zinc Bioaccumulated In Mycelial Biomass Of Edible Basidiomycetes.

Iron and zinc bioaccumulation in mycelial biomass of different medicinal basidiomycetes was evaluated in order to produce metal-enriched mycelial biomass as an alternative functional food from non-animal sources and based on biotechnology processes. Pleurotus ostreatus strain U2-9, U2-11, U6-8, and U6-9, Pleurotus eryngii strain U8-11, Schizophyllum commune strain U6-7, and Lentinula edodes strain U6-11 and U6-12 were grown in malt extract agar with or without addition of 50 mg/L iron or 7.5 mg/L zinc. The mycelial biomass was separated and iron and zinc concentrations were determined in a flame atomic absorption spectrophotometer. Basidiomycete strains presented different growth rates with the presence of iron and zinc; there was no dependence between the metal bioaccumulation and the fungal growth. The fungi presented greater capacity to bioaccumulate iron than zinc. P. ostreatus (U2-9) has greater iron bioaccumulation (3197.7 mg/kg) while P. ostreatus (U6-8) greater zinc bioaccumulation (440.4 mg/kg) in mycelial biomass. P. ostreatus (U2-9), P. ostreatus (U2-11), and S. commune (U6-7) had the highest metal translocation rates from the culture medium to mycelial biomass. The mycelial biomass enriched with iron or zinc is an alternative to a new functional food from non-animal sources.

Agaricus subrufescens: substratum nitrogen concentration and mycelial extraction method on antitumor activity.

Antitumor activity of Agaricus subrufescens has been shown on vegetative mycelium and basidiocarp. However, few studies have assessed the effect of A. subrufescens cultivation conditions and extraction methods on antitumor activity. This study evaluated the effect of nitrogen concentration on the cultivation medium of A. subrufescens and the extraction method of mycelial antineoplastic actives against sarcoma 180 cells implanted in mice. Two nitrogen sources (isolated soybean protein and NaNO3) and 10 nitrogen concentrations (0.25 to 8.0 g/L) were used. Dried mycelium extract was obtained by hot water infusion (1:10 mass:volume; 90 °C) or by aqueous mixture (1:10 mass:volume, ambient temperature) in ultrapure water. The doses were administered daily by gavage to mice implanted with sarcoma 180 cells. Isolated soy protein is more efficient to mycelial biomass production than NaNO3. The mycelial biomass production increases when the cultivation medium is added with high nitrogen concentrations as well as the splenic index and the antitumor activity of the moistened mycelial powder. Hot water extract is more effective than the moistened mycelial powder to reduce tumor. The antitumor activity of hot water mycelial extract is similar to the one of basidiocarps, presenting lower metabolic demand on the spleen, keeping blood parameters normal and promoting animal wellness.

Iron bioaccumulation in mycelium of Pleurotus ostreatus.

Pleurotus ostreatus is able to bioaccumulate several metals in its cell structures; however, there are no reports on its capacity to bioaccumulate iron. The objective of this study was to evaluate cultivation variables to increase iron bioaccumulation in P. ostreatus mycelium. A full factorial design and a central composite design were utilized to evaluate the effect of the following variables: nitrogen and carbon sources, pH and iron concentration in the solid culture medium to produce iron bioaccumulated in mycelial biomass. The maximum production of P. ostreatus mycelial biomass was obtained with yeast extract at 2.96 g of nitrogen L (-1) and glucose at 28.45 g L (-1) . The most important variable to bioaccumulation was the iron concentration in the cultivation medium. Iron concentration at 175 mg L (-1) or higher in the culture medium strongly inhibits the mycelial growth. The highest iron concentration in the mycelium was 3500 mg kg (-1) produced with iron addition of 300 mg L (-1) . The highest iron bioaccumulation in the mycelium was obtained in culture medium with 150 mg L (-1) of iron. Iron bioaccumulation in P. ostreatus mycelium is a potential alternative to produce non-animal food sources of iron.

Iron bioaccumulation in mycelium of Pleurotus ostreatus

Pleurotus ostreatus is able to bioaccumulate several metals in its cell structures; however, there are no reports on its capacity to bioaccumulate iron. The objective of this study was to evaluate cultivation variables to increase iron bioaccumulation in P. ostreatus mycelium. A full factorial design and a central composite design were utilized to evaluate the effect of the following variables: nitrogen and carbon sources, pH and iron concentration in the solid culture medium to produce iron bioaccumulated in mycelial biomass. The maximum production of P. ostreatus mycelial biomass was obtained with yeast extract at 2.96 g of nitrogen L−1 and glucose at 28.45 g L−1. The most important variable to bioaccumulation was the iron concentration in the cultivation medium. Iron concentration at 175 mg L−1 or higher in the culture medium strongly inhibits the mycelial growth. The highest iron concentration in the mycelium was 3500 mg kg−1 produced with iron addition of 300 mg L−1. The highest iron bioaccumulation in the mycelium was obtained in culture medium with 150 mg L−1 of iron. Iron bioaccumulation in P. ostreatus mycelium is a potential alternative to produce non-animal food sources of iron.