10-33: Cellulase production by an actinomycete isolated from a sugarcane region of Brazil

Streptomyces sp. SCPE-09, isolated from a sugar cane plantation environment of Pernambuco State, in Brazil, was selected as a promising cellulolytic strain, and   tested for its ability to produce cellulases in low cost residues. Sugar cane bagasse or wheat bran, tested as carbon source, and corn steep liquor, tested as nitrogen source, were used, varying concentrations according to an array of factorial design. The results showed that medium containing wheat bran 2% lead to the highest production of cellulases. A maximum of 2.004 U/ml of CMCase was obtained on the fourth day fermentation, when corn steep liquor was 0.19%. The strain behavior was tested under the best conditions set out by factorial design, in a 2.5L bioreactor, and was able to produce CMCase activity close to that observed in agitation flasks (1.71 IU/ml). For enzymatic activity characterization (CMCase) the supernatants obtained from the cultivation of Streptomyces sp. SCPE-09 was evaluated under the best condition stated by the planning. The pH and temperature profiled showed optimal activity at pH 4.9 and 50 °C. As to thermostability, endoglucanases presented best tolerance at 50 °C, retaining more than 80% of maximal activity even after 2 hours of incubation. Zymogram obtained using supernatant from growth in wheat bran detected the presence of two bands, with apparent molecular masses of 37 kDa and 119 kDa, repectively. The results obtained indicate that Streptomyces sp. SCPE-09 is promising for biotechnological applications, being capable of producing CMCase in low cost residues.