Abstract
The effects of riboflavin, pyridoxine, vitamin B12and nicotinic acid on the urease activity were studied, and the results obtained were as follows:-
1) The activity of urease preliminarily inactivated by AgNO3was not recovered by the addition of either10-3 M-riboflavin, 10-2 M-pyridoxine, 200γ%-vitamin B12 or 10-2 M-nicotinic acid.
2) 10-3 M-riboflavin, 10-2 M-pyridoxine, and 200γ-vitamin B12 caused respectively 24.7%, 19.0% and 14.2% inhibitions of the urease activity when they were added to urease solution in the presence of urea.
3) No inhibition on the activity was seen when 10-2 M-nicotinic acid was added to the urease solution in the presence of urea, while 8.08% inhibition was caused by the addition in the absence of urea.
