This study evaluated the production of cellulolytic enzymes by an Aspergillus fumigatus strain, isolated from sugar cane bagasse, according to its ability to grow on microcrystalline cellulose as the sole carbon source. The effect of the carbon source (brewer's spent grain, sugarcane bagasse, and wheat bran) and of the nitrogen source (corn steep liquor and sodium nitrate) on cellulase production was studied using submerged and solid state cultivations at 30 degrees C. The highest levels of endoglucanase (CMCase) corresponded to 365 U L(-1) and was obtained using sugarcane bagasse (1%) and corn steep liquor (1.2%) in submerged fermentation within 6 days of cultivation. This supernatant was used to run a sodium dodecyl sulfate polyacrylamide gel electrophoresis that showed six bands with endoglucanase activity. CMCase activity was higher at 65 degrees C and pH 2.0, indicating that this microorganism produces a thermophilic and acid endoglucanase. Solid state cultivation favored FPase production, that reached 47 U g(-1) of dry substrate (wheat bran and sugarcane bagasse) within 3 days.

Trichoderma atroviride 676 was studied to evaluate its efficiency in the production of some lignocellulolytic enzymes, using lignocellulosic residual biomass. Best results were obtained when 3.0 % (w/v) untreated sugarcane bagasse was used (61.3 U mL(-1) for xylanase, 1.9 U mL(-1) for endoglucanase, 0.25 U mL(-1) for FPase, and 0.17 U mL(-1) for β-glucosidase) after 3-4 days fermentation. The maximal enzymatic activity for endoglucanase, FPase, and xylanase were observed at 50-60 °C and pH 4.0-5.0, whereas thermal stability at 50 °C (CMCase and FPase) or 40 °C (xylanase) was obtained after 8 h. Zymograms have shown two bands of 104 and 200 kDa for endoglucanases and three bands for xylanase (23, 36, and 55.7 kDa). The results obtained with T. atroviride strain 676 were comparable to those obtained with the cellulolytic strain Trichoderma reesei RUT-C30, indicating, in the studied conditions, its great potential for biotechnological application, especially lignocellulose biomass hydrolysis.

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A cellulolytic bacterial strain, designated P118, isolated from the gut of the tropical fish Parotocinclus maculicauda was identified as belonging to the genus Paenibacillus based on phenotypic and chemotaxonomic characteristics and the 16S rRNA gene sequence. The novel strain was Gram-positive, spore-forming and rod-shaped. Catalase but not oxidase was produced. Carboxymethylcellulose was hydrolyzed but starch or gelatin was not. Acetoin production was negative whereas nitrate reduction and urease production were positive. Many carbohydrates served as carbon sources for growth. MK-7 was the predominant isoprenoid quinone. Anteiso-C 15:0 (38.73%) and C 16:0 (20.85%) were the dominant cellular fatty acids. Strain P118 was closely related to Paenibacillus amylolyticus NRRL NRS-290, P. pabuli HSCC 492, P. tundrae Ab10b, P. xylanexedens B22a, and P. tylopili MK2 with 98.3-98.8% 16S rRNA gene sequence similarity. The results presented here suggest that strain P118 represents a novel species of the genus Paenibacillus and it is a potential strain for further studies concerning its role in the production of industrially important products from cellulosic biomass.

Holocellulolytic accessory enzymes are very important in assisting hydrolysis of biomass. The use of these enzymes in the enzymatic hydrolysis of plant biomass is very important for obtaining building blocks in the concept of biorefinery. In previous studies, the mutant strain Trichoderma atroviride 102C1 was tested for production of endoglucanases, FPases and endoxylanases. This study aimed at evaluating the efficiency in holocellulolytic accessories enzymes production (-glucosidase, xylosidase and -L-arabinofuranosidase) by Trichoderma atroviride 102C1 using different lignocelluloses biomass as substrates. Accessory enzymes production was carried out in Erlenmeyer flasks containing Mandels salt medium, supplemented with different concentrations of sugarcane bagasse (SCB) and corn steep liquor (CSL), according to a Central Composite Rotational Design (CCRD). The fermentation system was incubated under agitation for 2 days / 28°C. For pH and temperature profile studies, a new CCRD was carried out. The best condition common to all enzymes, 55.4 U.mL-1 (β-glucosidase), 10.8 U.mL-1 (β-xylosidase) and 143.23 U.mL-1 (α-L-arabinofuranosidase), was observed when 2.5% (w/v) sugarcane bagasse (SCB) and 1.26% (w/v) of corn steep liquor (CSL) were used. All enzymes presented acidophilic characteristic in two different temperatures (44 and 55°C). The optimal profile characteristic for β-glucosidase and β-xylosidase activities were pH 5.0 and 3.0, respectively, both at 55°C, while for α-L-arabinofuranosidase it was pH 3.6 at 44°C. This study demonstrated the potential of T. atroviride 102C1 to produce three important holocellulolytic accessory enzymes in the presence of SCB and CSL, suggesting its use for enzymatic hydrolysis of lignocellulosic biomass.