Production and Micorbial Inhibition of Chitosan Hydrolyzates by Immobilized Chitosanase

• Main Authors: Hann-Liang Lin, 林翰良
• Other Authors: Jin-Hwei Rwan,Ph.D.
• Format: Others
• Language: zh-TW
• Published: 1995
• Online Access: http://ndltd.ncl.edu.tw/handle/02126833525573750320

碩士 === 東海大學 === 食品科學系 === 83 === The studies were focused on: firstly,investigation of opti- mum conditions for immobilization of chitosanase on crab chitin and on chitopearl; secondly,comparison of batch-wise or contin- uous-type hydrolysis of chitosan by the immobilized chitosanases ;and thirdly,comparison of the effect of chitosan and chitosan hydrolyzates on the growth of some bacteria. The suitable conditions for immobilizing chitosanase on chitin were using 40-60 mesh chitin particle size,and treating it with 0.75% glutaraldehyde solution before mixing with 3.6 mg protein/ g chitin..As to the suitable conditions for immobiliz- ing chitosanase on chitopearl were using 4.8 mg protein/g chitopearl. The suitable conditions for the batch-wise hydrolysis of chitosan with the chitin-immobilized chitosanase were a react- ion temperature of50℃,and an immobilized enzyme concentration of 2.0%(dw/v).As to the continuous process,in a column reactor packed with 2.0g(dw) of the immobilized enzyme, the most suit- able conditions for hydrolyzing chitosan were a flow rate 10mL /hr and reacction temperature of 30℃. As to the antibacterial effect of chitosan and chitosan hydrolyzates on some bacteria(E.coli,S.typhi,S.sureus,B.cereus) ,a chitosan hydrolyzate of 5% hydrolyzing degree showed an eff- ect stronger than chitosan and chitosan hydrolyzates of 10%,20% ,30% hydrolyzing degree,orderly,at the same concentration.Alth- ough chitosan hydrolyzates of higher hydrolyzing degree showed lower antibacterial effect than one of 5% hydrolyzing degree and chitosan at low concentration,they presented good effect at higher concentration.On other hand,chitosan hydrolzsates of 10% (or higher)hydrolyzing degree had water-soluble,low viscous, astrigentless taste properties those were usefully in food applications.