Page 87 - Feed Lab

Estimation of Urease Activity Suguna Management System Ver 1.0 / SOP / FQL / P2 - 13 Page 2 of 2

to7.04. If not, before using adjusts the pH of the FAt the end of 30 minutes, remove the container
solution with either a solution of strong acid or from the water bath and transfer the supernatant
strong base. The buffered solution has a useful life liquid to 25 ml beaker and read pH solution. The
of less than 3 months. difference the pH of the test sample (higher) and
that of the blank is a measure of the urease Activity
with sample. (Picture - 10)
Urea Buffer Solution(UBS)
Dissolve 15 g of urea, AR grade in 500 ml of PBS.
Adjust the pH if this urea solution to 6.96 to 7.04
using a solution of either a strong acid or a strong
base.

PROCEDURE
FWeigh 0.5g of the material into a container. Add 25
ml of UBS, stopper, and mix without inverting and
place in the water bath. (Picture - 6)
Picture - 7 Picture - 8
FSpread the sample of the Soya in a watch glass
heat it one hour to inactivate the enzyme. (Picture -
7)

FWeigh 0.5g of the inactivate material into container.
Add 25 ml of PBS, stopper, mix without inverting
and place in the water bath. (Picture - 8)

FIt is convenient to place the test and blank in the
water bath at exactly the same time. Mix the
contents of the both the sample and blank every 10
Picture - 9 Picture - 10
minutes during the digestion period. (Picture - 9)

CALCULATION
Urease Index (pH change) = (pH of test sample) - (pH of blank sample)

REFERENCE
1. Bureau of Indian Standard IS 7874 1975

2. Association of Official Analytical Chemist 2000.

Prepared by : Approved by :
75 Director - Technical