חיפוש מתקדם
תחביר
חפש...
הספר "אוצר וולקני"
אודות
תנאי שימוש
ניהול
קהילה:
אסיף מאגר המחקר החקלאי
פותח על ידי קלירמאש פתרונות בע"מ -
ABILITY OF VARIOUS CHEMICALS TO REDUCE COPPER AND TO INACTIVATE MUSHROOM TYROSINASE
Year:
1990
Source of publication :
Journal of Food Biochemistry
Authors :
כהן, ורדה
;
.
Volume :
14
Co-Authors:
ANDRAWIS, A., Department of Molecular and Cell Biology, Pennsylvania State University, University Park, Pennsylvania, 16802, United States
KAHN, V., Department of Food Science, Agricultural Research Organization, Volcani Center, P O. B.-6, Bet Dagan, 50250, Israel
Facilitators :
From page:
103
To page:
115
(
Total pages:
13
)
Abstract:
Treatment of mushroom tyrosinase with reducing agents such as hydrogen peroxide, ascorbic acid, phenylhydrazine, gallic acid, ferrocyanide and NH2OH resulted in inactivation of the enzyme. Under the conditions tested, 50% inactivation of the enzyme was obtained with 4 μM H2O2, 20 μM ascorbic acid, 40μM phenylhydrazine, 6 mM gallic acid, 12 mM ferrocyanide and 22 mM NH2OH. The ability of the reducing agents to reduce Cu2+ in a chemical model system was determined and it was found that gallic acid, phenylhydrazine, ascorbic acid and NH2OH are relatively good reductants of Cu2+ while H2O2 and ferrocyanide are relatively poor ones. The copper content of mushroom tyrosinase before and after inactivation by each of the reducing agents was determined. The copper content of the enzyme inactivated by H2O2, NH2OH, phenylhydrazine, ferrocyanide, gallic acid and ascorbic acid was 100%, 90%, 90%, 85%, 85% and 76% compared to that of the control (enzyme not treated). It was concluded that the degree of inactivation of mushroom tyrosinase by the reducing agents was not correlated with the decrease in the copper content of the enzyme nor with their ability to reduce Cu2+ in a chemical model system. Copyright © 1990, Wiley Blackwell. All rights reserved
Note:
Related Files :
עוד תגיות
תוכן קשור
More details
DOI :
10.1111/j.1745-4514.1990.tb00824.x
Article number:
Affiliations:
Database:
סקופוס
Publication Type:
מאמר
;
.
Language:
אנגלית
Editors' remarks:
ID:
22388
Last updated date:
02/03/2022 17:27
Creation date:
16/04/2018 23:51
Scientific Publication
ABILITY OF VARIOUS CHEMICALS TO REDUCE COPPER AND TO INACTIVATE MUSHROOM TYROSINASE
14
ANDRAWIS, A., Department of Molecular and Cell Biology, Pennsylvania State University, University Park, Pennsylvania, 16802, United States
KAHN, V., Department of Food Science, Agricultural Research Organization, Volcani Center, P O. B.-6, Bet Dagan, 50250, Israel
ABILITY OF VARIOUS CHEMICALS TO REDUCE COPPER AND TO INACTIVATE MUSHROOM TYROSINASE
Treatment of mushroom tyrosinase with reducing agents such as hydrogen peroxide, ascorbic acid, phenylhydrazine, gallic acid, ferrocyanide and NH2OH resulted in inactivation of the enzyme. Under the conditions tested, 50% inactivation of the enzyme was obtained with 4 μM H2O2, 20 μM ascorbic acid, 40μM phenylhydrazine, 6 mM gallic acid, 12 mM ferrocyanide and 22 mM NH2OH. The ability of the reducing agents to reduce Cu2+ in a chemical model system was determined and it was found that gallic acid, phenylhydrazine, ascorbic acid and NH2OH are relatively good reductants of Cu2+ while H2O2 and ferrocyanide are relatively poor ones. The copper content of mushroom tyrosinase before and after inactivation by each of the reducing agents was determined. The copper content of the enzyme inactivated by H2O2, NH2OH, phenylhydrazine, ferrocyanide, gallic acid and ascorbic acid was 100%, 90%, 90%, 85%, 85% and 76% compared to that of the control (enzyme not treated). It was concluded that the degree of inactivation of mushroom tyrosinase by the reducing agents was not correlated with the decrease in the copper content of the enzyme nor with their ability to reduce Cu2+ in a chemical model system. Copyright © 1990, Wiley Blackwell. All rights reserved
Scientific Publication
נגישות
menu      
You may also be interested in