Iron-enriched mycelia of edible and medicinal basidiomycetes.

Iron bioaccumulation in basidiomycetes is an alternative to recover ferrous sulphate from titanium dioxide pigment production and to produce an iron-enriched mycelial biomass. This study aimed to evaluate iron bioaccumulation capacity in vegetative mycelium of edible and medicinal fungi grown in malt extract liquid medium with different ferrous sulphate contents. Five basidiomycetes were grown in malt extract liquid medium with different iron contents from 0.116 to 100 mg L-1 iron. The iron content of dried mycelial biomass bioaccumulated with iron was determined by flame atomic absorption spectrophotometry. All fungi grew on the iron culture media and the mycelial biomass growth ranged from 3.24 ± 0.65a mg mL-1 to 12.46 ± 0.29 mg mL-1. Iron addition to culture media increased the iron content in the mycelial biomass from 4000-13,000-fold compared with control. Pleurotus ostreatus (2181 ± 218 mg kg-1) presented the greatest iron content in the mycelial biomass, followed by Schizophyllum commune (1769 ± 131 mg kg-1), Agaricus subrufescens (1272 ± 8.84 mg kg-1), and Ganoderma lucidum (840 ± 75 mg kg-1). P. ostreatus, followed by S. commune, and G. lucidum at 90 and 100 mg L-1 iron in the culture medium are the best choices to produce iron-enriched mycelial biomass. This extensive study of several edible and medicinal basidiomycetes grown in different iron contents was effective in recovering ferrous sulphate byproduct and transferring it to mycelium to produce a new nutraceutical food of iron-enriched mycelial biomass.

Iron biofortification and availability in the mycelial biomass of edible and medicinal basidiomycetes cultivated in sugarcane molasses.

Basidiomycetes can bioaccumulate high iron contents, but there are few studies on iron availability from the mycelial biomass in order to support their use as an iron-enriched fungal food. This study aimed to evaluate the in vitro iron bioaccumulation and availability in the mycelial biomass of edible and medicinal basidiomycetes grown in two distinct culture media. Lentinus crinitus, Ganoderma lucidum, Schizophyllum commune, Pleurotus ostreatus, Pleurotus eryngii, Lentinula edodes, and Agaricus subrufescens were grown in liquid culture medium of malt extract or sugarcane molasses to obtain iron-bioaccumulated mycelial biomass. P. ostreatus was the fungus that most bioaccumulated iron, followed by S. commune, and P. eryngii; they also had the highest mycelial biomass growth and iron transfer from the culture medium to the mycelial biomass. Mycelial iron availability is species-specific, regardless of the culture medium and the iron bioaccumulation capacity of the fungus in the mycelial biomass. Mycelial biomass of S. commune, followed by G. lucidum, P. ostreatus, and P. eryngii, associated with molasses culture medium, are the best choice for the production of iron-enriched mycelial biomass.

Modified grape stem as a renewable adsorbent for cadmium removal.

In order to aggregate value to the grape stem (wastes), this research aim was to increase the adsorption capacity of Cd2+ by chemical modifications on grape stems. The grape stems were milled and sieved, resulting in the biosorbent, which was used for the chemical modifications resulting in E. H2O2, E. H2SO4 and E. NaOH. These were characterized by such means as its pHPZC, Fourier transform-infrared (FTIR) spectroscopy, porosimetry, thermal stability and scanning electron microscopy. The ideal adsorption dose, the pH influence on adsorption, kinetics, equilibrium and thermodynamics studies were carried out. The FTIR spectroscopy suggests the occurrence of carboxyl, amine, and phenolic acting in Cd2+ sorption. The modification on grape biomass caused small increase in pore volume and specific surface area. The grape-based adsorbents have similar thermal stability, with irregular appearance and heterogeneity. 5.0 g kg-1 is the best adsorption dose. The modified adsorbents exhibited increase in Cd2+ removal of 66% for E. NaOH, 33% for E. H2O2 and 8.3% for E. H2SO4. The use of grape stem as adsorbent is an attractive alternative, because its wastes have great availability, low cost and great potential for metal adsorption processes.

Removal of cadmium from water using by-product Crambe abyssinica Hochst seeds as biosorbent material.

The effectiveness of Crambe abyssinica Hochst seeds by-product as a biosorbent for the removal of cadmium ions from wastewater was analyzed. The biomass of crambe was characterized by scanning electron microscopy, infrared spectroscopy and determining the point of zero charge. The optimum adsorption conditions obtained were 400 mg of biomass in a solution of pH 6.0 and contact time of 60 min to remove 19.342 mg g(-1) cadmium ions. The isotherms of adsorption were constructed and, according to the mathematical linearization, the best fitting followed the Freundlich and Dubinin-Radushkevich models, describing a multilayer adsorption and chemical interaction, also confirmed by the pseudo-second order model and enthalpy value. In the desorption process, about 79% of cadmium ions that had been adsorbed were recovered. The same conditions applied for studying the isotherms of adsorption and desorption were used for comparative study with activated carbon. It was concluded that the use of crambe by-product as biosorbent for cadmium removal in wastewaters was not only a viable alternative to activated carbon, but also required no previous treatment, so it represents a sustainable material with high applicability and low environmental impact.