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Abstract SUMMARY AND CONCLUSION The pattern for science and technology is tending towards ecofriendly material ”green technology” as a potential sustainable development, furthermore keep away from utilizing or generating whatever harmful substances, In that case, the innovative works of renewable biomass might have been exceedingly valued. Lignocellulose is the potency of renewable resource on earth. Nanotechnology offers enormous chances for change in the caliber of life, uses green nanotechnology to creating reasonable an assortment for nanosubstance, which achieve the welfare for human society in the close to future. So, the current studies were focused on: 1. Collection of agriculture wastes (rice straw, cotton stalks and corn cobs) to evaluate the most effective on cellulase activity. 2. selection of the most efficient isolates for cellulase production. 3. Conversion of rice straw to produce some nanosubstance (nanocellulose, nanosilica and nanolignin). 4. Some application of nanosubstances included as follow: a. Production of cellulase enzyme on nanocellulose as substrate: 1. Studying the effect of nanocellulose as a carbon source for cellulase production. 2. Studying the influence of nitrogen sources on cellulase production from nanocellulose. 3. Optimization of cellulase activity condition on nanocellulose with the most effective fungi by studying the interaction between some physical factor (pH, temperature, agitation, incubation period, inoculum size) and the nutritional factors (concentration of the nanocellulose and the best nitrogen source) using Response surface methodology (RSM). 134 b. Production of bioethanol from nanacellulose. c. Production of an adhesive substance from nanolignin. Results could be summarized in the following points: 1. Four fungal isolates (A2, A4, An2 and T3) as cellulase producers were collected from Microbiology Dept., Fac. of Agric., Ain shams Univ. 2. These isolates were identified based on their cultural and morphological characteristic which identified as one tested fungi Trichoderma sp. was classified as Trichoderma viride (T3) and three more of the tested fungi were identified as Aspergillus niger with codes A2, An2 and A4. 3. Out of the four isolates, two cellulase activity producing isolates of T. viride T3 and A. niger A4 were selected as the most efficiency isolates for cellulase production which ranged from 0.74 to 1.27 U/ml. 4. Three lignocellulosic wastes (rice straw, corn stalks and corn cobs) were pretreated with 4 different treatments (mechanical MT1, thermal TT2, acid (H2SO4) AT3 and Alkaline (NaOH) KT4). Alkaline pretreatment with 10% NaOH was the best one for cellulase production among the four treatments. 5. Alkaline pretreatment of rice straw was preferred as lignocellulosic waste for cellulase production by both the tested fungi than cotton stalks and corn cobs which cellulase activity ranged between 0.98 – 1.27 U/ml it might due to its attractive composition. 6. Production of nanosubstance from alkaline rice straw have economic importance as follows: a. Production of nanocellulose particles with size less than 10 nm. 135 b. Production of nanosilica particles with size less than 15 nm c. Nanolignin fibers with size ranged between 5 and 38 nm. d. It was found that the 100 g bulk rice straw gave 33.4g nanocellulose, 8.7 g nanosilica and 11.2 g nanolignin. 7. Measurement the size of partial purified cellulase enzyme which produced nanocellulose by consortium culture of T. viride T3 and A. niger A4 using the transimission electron microscope (TEM). It was found the size of enzyme was less than 67 nm. 8. Some applications of nanosubstances: 8.1. Cellulase production 8.1.1. Optimization of cellulase production using: 8.1.1.1.One – variable at a time approach. a. Nanocellulose as a carbon source affected on cellulase production by fungal consortium of T. viride T3 & A. niger A4, which gave high cellulase activity (2.04 U/ml) and 87.30 % of saccharification. b. Effect of twelve different nitrogen sources on nanocellulose were also studied. Results indicated that the mixture of urea, (NH4)2SO4, yeast extract and peptone in basal medium (medium 3) were the best nitrogen source for fungal consortium of T. viride T3 & A. niger A4 for cellulase activity. 8.1.1.2. Statistical of response surface methodology show that: a. Ten different variables including five nutritional factors (nanocellulose concentration as a sole of carbon source; ammonium sulfate, yeast extract, urea and pepton as a nitrogen source) and five physical factors (pH, temperature, inoculum size, incubation period and agitation speed) were screen for cellulase activity by fungal consortium of T. viride T3 & A. niger A4 using 136 the Plackett-Burman statistical experimental design. The most positive significant variables affecting cellulase production were inoculum size, nanocellulose and (NH4)2SO4. b. Optimized the most significant variable using response surface methodology (RSM) based central composite design (CCD). By using the surface plots and response optimizer of statistical software package Design – Expert software 9.0.0 (Stat-Ease, Inc., Minneapolis, MN 55413, USA 2104), the maximum cellulase activity by fungal consortium of T. viride T3 & A. niger A4 (4.92 U/ml) in the presence of nanocellulose (3.5g/L) and (NH4)2SO4 (0.93.g/L) with inoculum size (5%) 8.2. Production of Bioethanol 8.2.1. Evaluate the efficiency of S. cerevisiae ATCC 9763 and C. utilis ATCC 9256 for ethanol production which produced 0.16 g/100ml and 0.18 g/100 ml ethanol, respectively. 8.2.2. Test the efficiency of both yeast as individual and consortium to ferment nanocellulose into ethanol. It was observed that used yeast consortium of S. cerevisiae ATCC 9763 & C. utilis ATCC 9256 were better for ethanol production than individual yeast strain. The yeast consortium strains produced (0.22 g/100ml) ethanol with high yield and efficiency 50 % and 97.85 %, respectively. 8.3. Production of an adhesive Conversion nanolignin into adhesive substance with 230 ±47 Psi of strength. |