Effect of surfactants on the hydrolysis of lignocellulose by using Phanerochaete chrysosporium

• Main Authors: Yu-Hsuan Liu, 劉于萱
• Other Authors: 蘇文達
• Format: Others
• Language: zh-TW
• Published: 2010
• Online Access: http://ndltd.ncl.edu.tw/handle/ukmz6r

碩士 === 國立臺北科技大學 === 化學工程研究所 === 98 === Biomass energy is one of the most prominent topics in the world today. Lignocellulose is a suitable and noticeable raw material for further development in future. There are six million tons of agricultural waste produced every year in Taiwan, such as rice straw, sugarcane bagasse, waste of fruit and vegetable processing plants. In this study, we used rice straw and sugarcane bagasse as a substrate, and mixed with deionized water or acid and alkali, then followed with high pressure and temperature decomposition. We utilized basidomycetes, including Aspergillus niger and Phanerochaete chrysosporium with different ratio with pretreated substrate for liquid culture under pH 4, 37℃ and 130 rpm. The results showed that P. chrysosporium strains alone could produce 105.23 U/mL activity of the endo-β-1,4-D-glucanase, 10.24 U/mL activity of β-1,4-D-glucosidase and 1.77 mg/mL of reducing sugar for 120 hours cultivation. This result is better than the two strains coculture in different proportional mixing. In addition, surfactants could increase enzyme stability and enhance the enzymatic conversion of cellulose to reducing sugars. Therefore, we add different types of surfactants, such as chemical surfactant or biosurfactant into the medium to explore the effect of surfactant in the lignocelluloses hydrolysis. We seeded P. chrysosporium to rice straw substrate for 48 h liquid culture, then added 0.025 % non-ionic or anionic surfactants, including Tween 80, Triton X-100, Span 60, Polyethylene Glycol 4000, Sodium Dodecylbenzene Sulfonate, Sodium Laurylsulfate and Sodium Lauroyl Glutamate, in the medium for continuing to 96 hours. Experimental results showed that anionic surfactant SDBS had negative effect in promoting activity of enzyme and reducing sugar production for 96 hours culture. However added 0.025 % non-ionic surfactant PEG 4000, it can produce endo-β-1,4-D-glucanase 165.57 U/mL, β-1,4-D-glucosidase 40.58 U/mL, cellulase 0.50 FPU/mL and 3.03 mg/mL reducing sugar, respectively. That increased 2.05 times, 4.52 times, 3.13 times and 2.05 times compared with no added surfactant. Based results, PEG 4000 non-ionic surfactant could increase enzymatic activity and reducing sugar yield in the lignocelluloses hydrolysis process.