title: Stability of chitosan powder during long-term storage at room temperature.
abstract: Physicochemical and functional properties of two chitosan products [low viscosity (LV) with 16.8 mPa s; high viscosity (HV) with 369.4 mPa s] were evaluated during 9-month storage at room temperature. As storage time increased, increased moisture content and DPPH radical scavenging activity and decreased viscosity and water binding capacity (WBC) were observed. The extent (%) of decreased viscosity and WBC and of increased DPPH radical scavenging activity during storage were more pronounced with the HV chitosan. Significant correlations were observed between WBC and viscosity (r = 0.88 for LV; r = 0.96 for HV) and between DPPH radical scavenging activity and viscosity (r = -0.79 for LV; r = -0.87 for HV). Although significant differences in L*a*b* values were observed during storage, color differences were not easily discerned visually. Antibacterial activity of the HV chitosan against two Gram-negative and two Gram-positive bacteria significantly increased with increasing storage time.
authors.affiliation: Department of Food Science and Technology, Catholic University of Daegu, Hayang 712-702, South Korea. hkno@cu.ac.kr
authors.forename: Hong Kyoon
authors.initials: HK
authors.lastname: No
authors.forename: Witoon
authors.initials: W
authors.lastname: Prinyawiwatkul
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology; D055598:Chemical Phenomena; D048271:Chitosan / Q000737:chemistry* / Q000494:pharmacology*; D004355:Drug Stability; D004356:Drug Storage / Q000379:methods; D016166:Free Radical Scavengers / Q000494:pharmacology; D011208:Powders; D013997:Time Factors; D014783:Viscosity; D014867:Water / Q000032:analysis / Q000378:metabolism
chemical_list: D000900:Anti-Bacterial Agents; D016166:Free Radical Scavengers; D011208:Powders; D014867:Water; D048271:Chitosan