CHARECTERIZATION OF ENTEROTOXIN PRODUCED BY LOCAL ISOLATE OF YERSINIA ENTEROCOLITICA AND STUDY OF THE INHIBITORY EFFECT OF ERUCA SATIVA ON ITS ACTIVITY

Abstract

Enterotoxin produced by local isolate of Yersinia enterocolitica was purified
from the culture supernatant .The purification procedure involved precipitation by
ammonium sulfate (50% saturation ) and analyzed by sodium dodecyl sulfate- poly
acrylamide gel electrophoresis (SDS-PAGE), ( 159.4) fold purification was achieved
with yield of (17.9)%. The molecular weight of purified enterotoxin was 11,000
Dalton.
The purified enterotoxin was heat stable at 100 оC for 15 min, and the activity was
lost after incubation with 3mM dithiotheritol as reducing agent. Enterotoxic activity
of Y. enterocolitica was neutralized by antiserum from mice immunized with the
purified enterotoxin .The inhibitory activity of Eruca sativa extracts was tested, both
seed and leave extracts had inhibitory activity in a dose- dependent manner.