Hydrolysis of Chitosan, Chitosan-Polyoxyethylene and Chitosan-Poly(2-acryloylamido-2-methylpropanesulfonic acid) by a Crude Enzyme Complex from Trichoderma viride

The degradation of chitosan using a crude enzyme complex from the soil fungus Trichoderma viride was examined in terms of temperature, pH, enzyme activity and the presence of a polymer partner. It was found that chitosan hydrolysis is not suppressed by combining it with polyoxyethylene or poly(2-acryloylamido-2-methylpropanesulfonic acid). The results on Trichoderma viride immobilized on beads imply that chitosan, as well as its polymer complexes are appropriate carriers for development of ecologically safe phytosanitary preparations.

Preparation of PLLA/PEG Nanofibers by Electrospinning and Potential Applications

Poly(L-lactide) (PLLA)/polyethylene glycol (PEG) mixed solutions were successfully electrospun into micro-or nanofibrous polymer mats. The fiber diameter was in the range 100nm-6μm. The effect of the concentration of the spinning solutions and the ratio of PLLA/PEG on the fiber diameter and morphology was investigated. The hydrophilicity was tuned by varying the PLLA/PEG ratio. The tissue compatibility of the electrospun nanofibrous scaffolds was screened using two different cell models of human dermal fibroblasts and the osteoblast-like cell line MG-63. Both types of cells attached uniformly and approximately equally to all PLLA/PEG nanofibers. In long-term cultures osteoblast-like cells tend to spatially organize in tissue-like structure, particularly within the scaffold with the highest PEG content (PLLA/PEG at weight ratio 70/30). These results indicate that PLLA mixed with hydrophilic PEG produces a promising new biocompatible material for engineering scaffolds.