English  |  正體中文  |  简体中文  |  Items with full text/Total items : 17775/20116 (88%)
Visitors : 9441406      Online Users : 282
RC Version 7.0 © Powered By DSPACE, MIT. Enhanced by NTU Library IR team.
Scope Tips:
  • please add "double quotation mark" for query phrases to get precise results
  • please goto advance search for comprehansive author search
  • Adv. Search
    HomeLoginUploadHelpAboutAdminister Goto mobile version
    Please use this identifier to cite or link to this item: http://ir.cnu.edu.tw/handle/310902800/26814

    標題: 北蕉也酪胺酸酶與p-cresol之動力學分析
    A kinetic analysis of p-cresol oxidation by banana leaf tyrosinase
    作者: 吳鴻程
    貢獻者: 嘉南藥理科技大學食品科技系
    關鍵字: 酪胺酸酶
    banana leaf
    lag phase
    日期: 2012-12
    上傳時間: 2013-08-14 10:41:53 (UTC+8)
    摘要: 本研究擬以北蕉(Giant Cavendishii, AAA)葉所含酪胺酸酶為材料,探討其與單酚類基質p-cresol 作用產生遲滯期(lag phase)之動力學關係。北蕉葉之粗抽液經硫銨分劃後進行動力學分析,發現影響遲滯期主要因素有酵素與基質濃度、pH 值、添加微量雙酚以及基質配位基之位置特異性;在酵素濃度高、基質濃度低時會使遲滯期時間縮短;於pH 5.5 時之遲滯期最短;添加微量雙酚也會造成遲滯期縮短之現象, 以p-cresol 為基質時分別添加L-DOPA (L-dihydroxyphenylalanin)、catechol 獲得Kact(雙酚活化常數)分別為4.45μM、1.74μM;得知雙酚不同也會影響遲滯期長短,而且 L-DOPA 雙酚活化單酚酶能力低於catechol;另外基質取代基位置差異亦會影響遲滯期長短,使用othro-、mata-、para-等不同氯取代位置cholrophenol 當基質時,發現遲滯期時間由短至長順序為p-、 o-、, m-,同時發現香蕉葉酪胺酸酶可作用具有毒性的氯酚化合物。經由本研究可了解農業廢棄物香蕉葉中所含的酪胺酸酶作用p-cresol 的遲滯期與動力學機制並得知其對單酚基質具有廣特異性,期待將這些特性應用於工業合成及廢水處理。
    This kinetic analysis of p-cresol by tyrosinase was investigated in this study. The tyrosinase used in this study was extracted from the leaf of banana (Giant Cavendishii, AAA) and partially purification by ammonium sulfate fractionation. The activity was determined by a lag period, that duration depended on the monophenol and its concentration, as well as enzyme concentration, pH, and the presence of catalytic amounts of diphenol. Moreover, the lag phase decreased with increasing diphenol concentration, it was possible to evaluate Kact, the activation diphenol constant, which showed a value of 4.45μM toward L-DOPA and 1.74μM for catechol. Substitution of chlorine at different position of phenol was exhibited different hydroxylation rate with an order of para>ortho>meta. The results from this study indicates that banana leaf tyrosinase exhibit wide substrate specificity toward monophenol, making its potential in medical and industry.
    關聯: 嘉南學報(科技類) 38期:p.110-115
    Appears in Collections:[嘉南學報] 38 期 (2012)
    [ 食品科技系 ] 期刊論文
    [藥學系(所)] 期刊論文
    [化妝品應用與管理系(所)] 期刊論文

    Files in This Item:

    File SizeFormat
    38_110_115.pdf1001KbAdobe PDF1312View/Open

    All items in CNU IR are protected by copyright, with all rights reserved.

    DSpace Software Copyright © 2002-2004  MIT &  Hewlett-Packard  /   Enhanced by   NTU Library IR team Copyright ©   - Feedback