Chitosan (CS) membranes obtained by electrospinning are potentially ideal substrates for soft tissue engineering as they combine the excellent biological properties of CS with the extracellular matrix (ECM)-like structure of nanofibrous mats. However, the high amount of acid solvents required to spun CS solutions interferes with the biocompatibility of CS fibres. To overcome this limitation, novel CS based solutions were investigated in this work. Low amount of acidic acid (0.5M) was used and dibasic sodium phosphate (DSP) was introduced as ionic crosslinker to improve nanofibres water stability and to neutralize the acidic pH of electrospun membranes after fibres soaking in biological fluids. Randomly oriented and aligned nanofibres (128±19nm and 140±41nm, respectively) were obtained through electrospinning process (voltage of 30kV, 30μL/min flow rate and temperature of 39°C) showing mechanical properties similar to those of soft tissues (Young Modulus lower than 40MPa in dry condition) and water stability until 7 days. C2C12 myoblast cell line was cultured on CS fibres showing that the aligned architecture of substrate induces cell orientation that can enhance skeletal muscle regeneration.
Sustainable crop production includes methods of growing food in a responsible manner avoiding application and dependence on chemically produced fertilizers and pesticides. The latter means development of approaches that lead to environmentally mild inputs based on the production-consumption-recycling principle. Biofertilizers are an important tool to achieve sustainable crop production. In this work, we report the results of experiments on growth and spore/mycelium production of plant growth promoting A. niger applying standard nutritional medium (potato-dextrose broth, PDB) enriched with 3% insoluble phosphate (20 to 200 mesh hydroxyapatite of animal-bone origin, HABO) and 0 to 80 g/L glycerol (a by-product of biodiesel production. Results showed the ability of A. niger to acidify the medium with the highest titratable acidity of 28.9 mmol/1 (at 5% of glycerol) and solubilize animal bone char under these conditions. As a second stage of the experimental work, the resulting final products were used to formulate gel-based inoculant. Both, the spores and mycelium produced during the fermentation process were further used as a base for formulation to make the biofertilizer production the key in the Sustainable Agriculture. Storage of the resulting products reported here was facilitated by the presence of glycerol in the formulation system.
Sustainable crop production includes methods of growing food in a responsible manner avoiding application and dependence on chemically produced fertilizers and pesticides. The latter means development of approaches that lead to environmentally mild inputs based on the production-consumption-recycling principle. Biofertilizers are an important tool to achieve sustainable crop production. In this work, we report the results of experiments on growth and spore/mycelium production of plant growth promoting A. niger applying standard nutritional medium (potato-dextrose broth, PDB) enriched with 3% insoluble phosphate (20 to 200 mesh hydroxyapatite of animal-bone origin, HABO) and 0 to 80 g/L glycerol (a by-product of biodiesel production. Results showed the ability of A. niger to acidify the medium with the highest titratable acidity of 28.9 mmol/1 (at 5% of glycerol) and solubilize animal bone char under these conditions. As a second stage of the experimental work, the resulting final products were used to formulate gel-based inoculant. Both, the spores and mycelium produced during the fermentation process were further used as a base for formulation to make the biofertilizer production the key in the Sustainable Agriculture. Storage of the resulting products reported here was facilitated by the presence of glycerol in the formulation system.