Abstract:
Protease constitute a large group of highly demanded enzymes having huge application in
various industries. This study was carried out with an aim to extract protease from kinema
prepared from white soybean, partial purify the extracted protease by ammonium sulphate
precipitation followed by dialysis and to determine general characteristics of the purified
protease. The kinema, which has highest proteolysis activity after completion of three days
fermentation was taken for the study. The data were analyzed by using one way ANOVA
using Genstat at 5% level of significance level.
About 2.5 fold of purification with overall recovery of 71.7% was achieved after
precipitation with ammonium sulphate at 30-70% saturation followed by dialysis of crude
extracted protease. The specific activity was found to be 7.67 U/mg/min. The enzyme was
found active over various natural substrates; showing highest activity on casein, followed by
BSA, gelatin, hemoglobin and whey protein. Metal ions such as Iron, Mercury and aluminum
shows the inhibition effect whereas presence of sodium, cobalt, zinc, copper, calcium,
potassium shows the activation effect on protease activity. Furthermore, the enzyme activity
was highly inhibited with EDTA and then PMSF at 5mM concentration, suggesting the
protease from kinema was a metal dependent serine protease.
Description:
A dissertation submitted to the Department of Food Technology, Central Campus of
Technology, Tribhuvan University, in Partial fulfillment of the requirements for the
degree of B. Tech in Food Technology