以天然玉米秸秆为原料研究碱法-酶法制糖工艺，考察了碱预处理条件对样品组分变化、酶解效率和总糖得率的影响。试验结果表明，碱预处理具有良好的木素脱除效果，但会伴随半纤维素的损失，为了获得高的总糖得率，必须适当降低预处理强度。试验范围内固液比1∶10，预处理条件为1.5 % NaOH，80 ℃下反应1 h时，总糖得率最高。固相中保留了近100 %纤维素和6958 %半纤维素，木素去除率为54.84 %。预处理样品在底物质量浓度30 g/L，酶用量为纤维素酶15 μmol/(min·g)，纤维二糖酶30 μmol/(min·g)，水解48 h,纤维素酶解得率从24.18 % 上升至71.29 %，半纤维素酶解得率达到78.85 %。整个工艺总糖得率为66.86 %，较未处理样品提高46.66 %。
Abstract
Preparation conditions of sugar from corn stalk by alkali pretreatment and enzymatic hydrolysis were investigated. Influence of NaOH pretreatment conditions on the compositional changes, enzyme hydrolysis efficiency and total sugar yield were examined. Test results showed that the NaOH pretreatment had a good effect of lignin removal,but the loss of hemicellulose was difficult to avoid.In order to get a high sugar yield, the strength of pretreatment needed be reduced as appropriate, within the experiments.The pretreatment condition of the maximum overall sugar yield was found to be 1.5 % of NaOH, 80 ℃,1∶10 solid to liquid ratio, and 1 h reaction time. The pretreated corn stalk solid retained 100 %cellulose and 69.58 % hemicellulose, but 54.84 % lignin was removed. The enzymatic digestibility of the cellulose content increased from 24.18 % to 71.29 % with 15 μmol/(min·g) and 30 μmol/(min·g) cellulose enzymes loading, where as the digestibility of hemicellulose content increased to 78.85 %. Under this condition, the overall sugar yield increased form 20.20 % to 66.86 %, compared with untreated corn stover.
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参考文献
[1]李冬敏,陈洪章.变温调控对汽爆秸秆发酵产氢的影响[J]. 生物质化学工程,2007,41(3):11-14.
[2]包红旭,任南琪,王爱杰. 一株纤维素降解新菌种发酵玉米秸秆的生物产氢特性研究[J]. 太阳能学报,2008,29(7):775-780.
[3]谢天卉,任南琪,邢德峰,等. 磷酸盐浓度对产氢细菌Ethanoligenens harbinense YUAN3生长和产气的影响[J]. 太阳能学报,2009,30(6):846- 849.
[4]董玲玲,牛涛,李德莹,等. 半纤维素和木质素去除对纤维素糖化过程的影响[J]. 农产品加工·学刊,2009,169(4):31-34.
[5]Kumar R, Mago G, Balan V, et al. Physical and chemical characterizations of corn stover and poplar solids resulting from leading pretreatment technologies[J]. Bioresource Technology, 2009, 100: 3948-3962.
[6]葳力斯,段开红,刘潇,等. 预处理对甜高粱秸秆纤维素降解影响的初步研究[J]. 酿酒,2009,36(3):61-63.
[7]Michael J S, Todd B V, Michael E H, et al. The effect of lignin removal by alkaline peroxide pretreatment on the susceptibility of corn stover to purified cellulolytic and xylanolytic enzymes [J]. Applied Biochemistry and Biotechnology, 2009, 155(1-3): 94-103.
[8]Ohgren K, Bura R, Saddler, et al. Effect of hemicellulose and lignin removal on enzymatic hydrolysis of steam pretreated corn stover[J]. Bioresource Technology, 2007, 98: 2503-2510.
[9]张学金,李友明,陈克利,等. 甘蔗渣的NaOH预处理研究和氧碱制浆[J]. 纸和造纸,2008,27(4):16-20.
[10]Kim T H, Lee Y Y. Pretreatment of corn stover by soaking in a queous ammonia at moderate temperatures[J]. Applied Biochemistry and Biotechnology,2007,137: 81-92.
[11]Sluiter A, Hames B, Ruia R, et al. Laboratory analytical procedure[S]. American: NREL Biomass Program, 2004.
[12]Bak J S, Ko J K, Han Y H, et al. Improved enzymatic hydrolysis yield of rice straw using electron beam irradiation pretreatment[J]. Bioresource Technology, 2009, 100: 1285-1290.
[13]Jeya M, Zhang Y W, Kim I W, et al. Enhanced saccharification of alkalitreated rice straw by cellulase from Trametes hirsuta and statistical optimization of hydrolysis conditions by RSM[J]. Bioresource Technology, 2009, 100: 5155-5161.
[14]李科,靳艳玲,甘明哲,等. 木质纤维素生产燃料乙醇的关键技术研究现状[J]. 应用与环境生物学报,2008,14(6):877-884.
[15]AlZuhair S. The effect of crystallinity of cellulose on the rate of reducing sugars production by heterogeneous enzymatic hydrolysis[J]. Bioresource Technology, 2008, 99: 4078-4085.
[16]Kumar R, Wyman C E. Effect of xylanase supplementation of cellulase on digestion of corn stover solids prepared by leading pretreatment technologies [J]. Bioresource Technology, 2009, 100: 4203-4213.
基金
收稿日期：2009-10-13修回日期：2009-12-23基金项目：国家高技术研究发展计划(2007AA02Z213，2006AA020204)；国家重点基础研究发展计划(2007CB707801)作者简介：欧阳嘉(1972—)，副教授，博士。Email: Jia_ouyang72@hotmail.com。引文格式：欧阳嘉,李鑫,董郑伟,等
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