Sweet potato bete-amylase immobilized on chitosan beads and its application in the semi-continuous production of maltose

This study has investigated the potential usefulness of phosphated chitin (P-chitin) as an anti-inflammatory agent in a mice model of chitosan-induced acute respiratory distress syndrome. A unique model of interstitial pneumonia that mimics acute respiratory distress syndrome was developed by an overdose of an intraperitoneal injection of chitosan suspension at the rate of 1¯4 g/kg body weight over a period of 24¯48 h. Pneumonia thus induced was blocked by a simultaneous intravenous injection of Pchitin at the rate of 8¯40 mg/kg body weight. The protective effects of P-chitin were evaluated, based mainly on the computerized image analysis of the histological lung sections, for the degree of infiltration in the interstitial and alveolar spaces by the neutrophils and other cellular and non-cellular elements. Intravenous infusion of some P-chitin formulations dramatically reduced lung injury and diminished the accumulation of neutrophils in the interstitial and alveolar spaces of the lungs, whereas other P-chitin had no such effects. Of the nine types of P-chitin tested, only three P-chitin formulations were significantly effective in the prevention of pneumonia. P-chitin with a molecular weight of 24000, the degree of substitution at 58%, and the degree of deacetylation at 4% was found to be most effective in blocking the chitosan induced lung injury when administered at 8 mg/kg level. The degree of blockage of pneumonia by P-chitin was comparable (significant at p<0.05 level) to that of control (only chitosan). The present results suggest that P-chitin may be used as a novel antiinflammatory agent. The possible mechanism of action for this phenomenon is under investigation.