Cc . the Action of Dyestuffs on Enzymes

The method of investigation consisted in submitting a preparation of urease to the action of a dyestuff at PHI 7-4 and at 450 for a given time, usually 30 mins. or 1 hour, and in then determining the activity of the enzyme by estimating the amount of ammonia produced at 450 in a given time from a 0 3 % solution of urea. 1 cc. of the enzyme preparation was added to 2 cc. M/15 phosphate buffer solution PH 7-4 and then the dyestuff and any other substance under investigation. The volume was made up to 9 cc. with distilled water and the mixture was incubated at 450 for the required interval of time (referred to as the initial incubation period). 1 cc. 3 % urea was then added and incubation was allowed to proceed at 450 for a further interval (referred to as the final incubation period). At the close of this interval the free ammonia was estimated on 1 cc. by a suitable aeration method and compared with that obtained from urease treated under similar conditions but in the absence of dyestuff. The amount of enzyme preparation taken was usually that required to decompose 1 cc. 3 % urea at 450 and at an initial PH of 7-4 in one hour.