الفهرس 
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Abstract
This study has formed a baseline for further studies on the chemical and enzymatic hydrolysis of sugarcane bagasse from Egyptian sugarcane factories. The conclusions drawn from this study are as follows:
Bagasse composition in our results consists of approximately 42.78 % and 22.32 % of cellulose and lignin, respectively. Ash percentage in our results was 2.68 % and 2.25 of bagasse before and after SCB pretreatment, respectively. The optimum delignification (74.22 %) was recorded at 2 % alkaline concentration of NaOH. Optimization of culture conditions for enzyme production by A. niger or T. harzianum in presence of treated sugarcane bagasse as a sole carbon source showed the following optimum conditions: Production of CMC-ase by A. niger and T. harzianum increased with the increasing in incubation period (9 and 7 days) and reached maximum (0.2697 IU/ml, 0.1985 IU/ml), respectively. The highest level of enzyme formation was obtained when nitrogen source of urea was used for A. niger, and ammonium chloride for T. harzianum. Our results show that performing agitation (at 120 rpm) to the culture medium improved enzyme production more than static cultures either for Trichoderma or Aspergillus. Cultures in agitation under optimum conditions improved enzyme activity from 3-4-folds more than static and non-optimum conditions.
In chemical hydrolysis, the highest percentage of reducing sugar (RS) was 34.564 in the experiment carried out at 4 % H3PO4, at 100 °C, and after incubation period of 3 hrs However, at the highest temperature (120 °C), a slight decrease in RS concentration occurred compared with the other produced at 90 and 100 oC temperatures of hydrolysis. RS produced by phosphoric acid hydrolysis of TSCB proportionally increased with increasing the acid concentration from (0.5 – 6 %). Mostly, production of RS increased with acid concentration increasing as well as hydrolysis by H3PO4, except for incubation temperature of 120 °C, whereas, RS greatly decreased with increasing of acid concentration starting at the point of 1 % of H2SO4 concentration RS concentration was always increased with increasing acid concentration except in the range of 4-6 % HClO4 of high concentrations at all incubation temperature and incubation periods. Prolongation time increased TSCB hydrolysis by HClO4 at 100 oC and decreased at 120 oC. H2SO4 gave higher hydrolysis efficiency for sugarcane bagasse at lower temperature, therefore, treated sugarcane bagasse hydrolysis using 4 % of H2SO4 at 90 oC for 3 hrs was the optimum conditions performed in producing of RS for fermentation experiment. This treatment when neutralized, amended with some nutrients and inoculated with 2 % of Saccharomyces cerevisiae yeast, achieved the highest ethanol concentration (1.145 % v/v) using H2SO4 as catalyst. The highest bioconversion of 5 % TSCB (63.425 % w/w) was recorded by A. niger. Results show that ethanol yield by fermentation was maximum in case of A. niger hydrolysates (0.2484 g/g), followed by hydrolysates of sulphuric acid ( 0.1798 g/g ), and in the last the hydrolysates of T. harzianum (0.1292 g/g) using 5 % (w/v) as initial substrate of TSCB.