Full-Text Search:
Home|About CNKI|User Service|中文
Add to Favorite Get Latest Update

STUDIES ON POLYPHENOL OXIDASE IN TOBACCO CALLU CULTURES

Bi Yu-rong and Liang Hou-guo (Laboratory of Plant Physiology,Lanzhou University)  
Many studies have been made on poly-phenol oxidase in plant tissues.However,there are only a few reports on the polyphenol oxidase in plant callus.In this paper,the callus cultures of Nicotiana tobacum cv.Wil-low leaf were used as experimental materials in order to clear some properties and changes of polyphenol oxidase during callus differen-tiation and organ formation. The polyphenol oxidase of tobacco callus can oxidize catechol and hydroquinone,but the activity oxidizing hydroquinone was ra-ther low.Two activity peaks of the enzyme were observed around PH5.6 and PH7.4 with catechol as substrate.The polyphenol oxidase activity was obviously inhibited by KCN, Dieca and m-CLAM.According to the gel electrophoresis analysis,the isoenzymes of polyphenol oxidase in subcultured callus ex-pressed five bands,but in the callus differen-tiating into bud and the small leaves regene-rated from callus seven to eight bands were observed.During the 18 days of culture,the polyphenol oxidase activity of subcultured callus did not change obviously.The polyphe-nol oxidase activity of differentiating callus was much higher than that of subcultured callus.A significant increase in polyphenol oxidase was observed during bud formation,at the same time the inhibition of Dieca on respiration also increased from 32% to 47%.
Download(CAJ format) Download(PDF format)
CAJViewer7.0 supports all the CNKI file formats; AdobeReader only supports the PDF format.
©CNKI All Rights Reserved