BackgroundSugarcane bagasse was shown to be an adequate substrate for the growth and aroma production by Trichoderma species. In the present work the ability of Trichoderma viride EMCC-107 to produce high yield of coconut aroma in solid state fermentation (SSF) by using sugarcane bagasse as solid substrate was evaluated. The produced aroma was characterized.ResultsTotal carbohydrates comprised the highest content (43.9% w/w) compared with the other constituents in sugarcane bagasse. The sensory and gas chromatography–mass spectrometric (GC–MS) analysis revealed that the highest odor intensity and maximum yield of volatiles were perceived at the 5th d of induction period. The unsaturated lactone, 6-pentyl-α-pyrone (6-PP), was the major identified volatile compound. Saturated lactones, δ-octalactone, γ-nonalactone, γ-undecalactone, γ-dodecalactone and δ-dodecalactone, were also identified in the coconut aroma produced during the induction period (12d). A quite correlation was found between the composition and odor profile of the produced aroma. The effect of varying the concentration of sugarcane bagasse on 6-PP production and biomass growth was evaluated. The results revealed high 6-PP production at 4.5g sugarcane bagasse whereas the biomass showed significant (P<0.05) increase by increasing the concentration of sugarcane bagasse.ConclusionThe concentration of 6-PP, the most contribution of coconut aroma, produced in present study (3.62mg/g DM) was higher than that reported in previous studies conducted under the same fermentation conditions. The significant increase in biomass with increasing the concentration of sugarcane bagasse may be attributed to the increase in sugar content that acts as carbon and energy source

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Protease enzyme from Bacillus megaterium was successively purified by ammonium sulfate precipitation, ion exchange chromatography on DEAE-cellulose and gel filtration chromatography on Sephadex G-200. The purification steps of protease resulted in the production of two protease fractions namely protease P1 and P2 with specific activities of 561.27 and 317.23Umg−1 of protein, respectively. The molecular weights of B. megaterium P1 and P2 were 28 and 25KDa, respectively. The purified fractions P1 and P2 were rich in aspartic acid and serine. Relatively higher amounts of alanine, leucine, glycine, valine, thereonine valine and glutamic acid were also present. The maximum protease activities for both enzyme fractions were attained at 50°C, pH 7.5, 1% of gelatine concentration and 0.5 enzyme concentrations. P1 and P2 fractions were more stable over pH 7.0–8.5 and able to prolong their thermal stability up to 80°C. The effect of different inhibitors on the protease activity of both enzyme fractions was also studied. The enzyme was found to be serine active as it had been affected by lower concentrations of phenylmethylsulfonyl fluoride (PMSF). Complete dehairing of the enzyme-treated skin was achieved in 12h, at room temperature