Prime Enzymatic Exocellular Background of &i&Lysinibacillus louembei&/i&

摘要

Many high-reading journals reject several studies based on the basic aspects of microbiology by forgetting that this could open doors and windows of great scientific discoveries. A new spore-forming bacteria species called Lysinibacillus louembei has been previously discovered in our research unit. This new study aims to assess a real enzymatic machine produced with such bacteria. Using agarose mixed with half skimmed milk, LB medium supplemented with tween 20, Olive oil, egg yolk, cellulose, casein, pectin and starch, we showed that L. louembei has lipolytic, proteolytic (2.8 cm ± 0.1), cellulolytic, amylolytic pectinolytic activities, with percentage ranging from 30% to 80%. This species is able to secrete lipase, thermostable protease up to 60°C. Cellulase, pectinase and amylase are secreted with more stability between 30°C and 50°C with an optimum at 45°C. The effect of pH was determined after 24 h of incubation at 37°C and 50°C. The proteolytic activity is stable at pH 8 at 50°C. In addition to this first enzymatic landscape, L. louembei is able to degrade and/or tolerate gasoline and/or diesel fuel hydrocarbons in 36 hours. In this work, we also showed that L. louembei can produce biosurfactant in the presence of gasoline and SAE140 with the E24 up to 50%.