Ngo- Itsouhou^{1, 2}, Etienne Nguimbi^{1, 3,}, Rachel Moyen¹, Armel Faly Soloka Mabika^{1, 3}

The biological activities of bacteria of the genus Bacillus (MN6. MN7, MN12, MN14, MN17, and MN26) isolated from the soils at Brazzaville were explored. The capacity of six strains to produce hydrolytic enzymes, in particular: proteases, lipases, amylases, cellulases was evaluated. The antibacterial activity of each strain of Bacillus for three pathogenic strains (Escherichia coli MN40, Salmonella typhimurium MN42, Pseudomonas aeruginosa MN41) was also tested. The methods of petri dishes containing the substrate relating to the search for each hydrolytic activity were used. All Bacillus strains grow under these culture conditions. The growth of each strain of Bacillus correlated with the production of protease gave values for the optical density respectively between 0.75 ± 0.2 and 0.99 ± 0.1, while the production of proteolytic enzyme values between 11.1 ± 0.04 and 20 ± 0.11 Two strains of Bacillus MN7 and MN17 produce amylases. The MN17 strain was tested producing lipase. The MN12, MN17, MN26 strains were tested positive for the production of cellulases. The other three strains of Bacillus MN6, MN7, MN14 were tested negative for cellulase production. A principal component analysis revealed that all of the strains have antibacterial activity against at least one of the three pathogenic strains indicated. A principal component analysis indicates that the antibacterials produced by the MN6, MN14 and MN17 strains are very effective at the three pathogenic strains with greater efficacy of MN17 on E. coli MN40. MN7, MN12 and MN14 produce antibacterials which neutralize the bacteria Salmonella typhimurium MN42, Pseudomonas aeruginosa MN41. These bacteria isolated from the soil in Brazzaville, produce bioactive compounds of biotechnological interest.

exploitation, biological activities, Bacillus, soil, bioactives compounds