Résumé:
This work aimed to the isolation and the search for hydrolytic bacteria from soil samples. The
screening of the different hydrolytic activities (proteolytic, lipolytic, amylolytic and cellulolytic) on
nutrient agar supplemented with various substrates: sklmmed milk, tween 80, starch and cellulose
showed that 27 isolates had at least one hydrolytic activity, with the first three substrates; however,
with cellulose no hydrolysis zone was detected. The isolate 41 was selected for its ability to produce
three outstand.ing hydrolytic activities simultaneously. The study of microscopie, macroscopic and
biochemical characters reveals that this strain belongs to the genus Bacillus sp. The results of enzyme
assays after culturing on liquid media showed tbat the protease and the lipase are produced in high
levels in the presence of corresponding substrates. In addition, the crude enzyme extract sbowed a
detergent activity on red sauce stains.
