The biosurfactants are grown from microrganisms and are compounds with low toxicity and high biodegradability ability to reduce surface and interfacial tensions. Due to the advantage of being more biodegradable compared with those of chemical origin, they are most appropriate for application in biological treatment systems, assisting in the bioavailability of oil and grease ound in some industrial effluents food source. This study aims to optimize the production of biosurfactant by Bacillus subtilis and Bacillus velezensis through distinct substrates in solid state fermentation and using the biosurfactant produced in the biological treatment of industrial effluents containing oil and grease. To do so, will be used three different substrates: wheat bran, cassava bagasse and crueira. Fermentation will occur in polyethylene bags with 10 grams of solid substrate plus buffer-glycerol phosphate and the concentration to obtain 40, 60 and 80% humidity and are incubated at 37 ° C for 96 hours. Analysis will be made of surface tension, critical micelle concentration, and emulsification activity and index emulsficante. After optimization, the best results for biosurfactant production will be applied at concentrations of 2, 5 and 8% for the anaerobic treatment of dairy wastewater, refrigerator and manipueira.
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