摘要
为探寻环境友好的秸秆预处理方法,提高秸秆等生物质资源的利用效率,以水稻秸秆为原料,采用3种不同的低温等离子体装置:灭菌柜、介质阻止放电及射频电容耦合对其进行预处理,分别对3种方法的处理条件进行优化,并在此基础上考察预处理后秸秆对纤维素酶的吸附能力及纤维素和半纤维素的糖化效率。结果表明,与未处理的秸秆对照相比,3种方法均可以降低水稻秸秆对纤维素酶的吸附能力,同时提高秸秆中纤维素和半纤维素的糖化率;其中,介质阻挡空气放电对秸秆的处理效果最好,秸秆对酶的吸附率比未处理秸秆的对照组降低了67.6%,而纤维素和半纤维素的糖化率分别比未处理秸秆的对照组提高了34.6%和44.7%。该研究为今后利用低温等离子体预处理秸秆相关技术的改进和深入研究提供了参考。
A key issue for utilization of lignocellulosic biomass is the disruption of complex matrix of polymers to liberate the monosaccharides. Thus, development of pretreatment methods that increase the material digestibility for the subsequent enzymatic hydrolysis becomes a focus in this research field. In order to enhance the enzymatic saccharification of rice straw, three low temperature plasma technologies including low temperature plasma sterilizer （LTPS）, dielectric barrier discharge plasma （DBD）, and capacitively coupled radio-frequency discharge plasma （CCRFD） were employed to pretreat rice straw. Firstly, the operating conditions for each of the three plasma tech- nologies were investigated. The optimum parameters were found to be： （1） Low temperature plasma sterilizer： dis- charging with a power of 360 W and reaction time of 10 min; （2） Dielectric barrier discharge plasma： discharging in air with a voltage of 45 V and electric current of 3.53 A; （3） Capacitively coupled radio-frequency discharge plasma： discharging with a power of 10 W, reaction time of 5 rain and discharge pressure of 20 Pa. Secondly, the effects of plasma pretreatments on enzyme adsorption ability and enzymatic saccharification of rice straw were investigated based on the optimum operating conditions. The results indicated that all of the three plasma pretreatments could reduce the enzyme adsorption and enhance enzymatic saccharification office straw, among which dielectric barrier discharge plasma had the highest efficiency. Compared to the untreated rice straw, dielectric barrier discharge plasma contributed to a 67.6% reduction of enzyme adsorption, and increases of 34.6% of cellulose saccharification and 44.7% of hemicelluloses saccharification, respectively. The effect of capacitively coupled radio-frequency discharge plasma on saccharification office straw was less than dielectric barrier discharge plasma, which led to a 58.4%reduction of enzyme adsorption, and increases of 22.5% of cellulose saccharification and 19.2% of hemicelluloses saccharification, respectively. The cellulose and hemicelluloses saccharification of rice straw pretreated by low tem- perature plasma sterilizer were only increased by 12.1% and 14.2%, although the enzyme adsorption of it was re- duced by 48.9%. These results indicated that low temperature plasma pretreatment may partially disrupt the lignin structure and expose more accessible surface area of cellulose to cellulase.-Furthermore, lignin removal could also reduce unproductive binding of cellulase to lignin. Consequently, it improved enzymatic biocatalysis, increased the yields of desired products, and recycled more cellulase. Thus, the costs associated with enzymatic sacchafification of biomass could be remarkably reduced. The present work may provide reference for further improvement of low temperature plasma technology in straw pretreatrnent.
出处
《安徽农业大学学报》
CAS
CSCD
北大核心
2014年第6期1046-1054,共9页
Journal of Anhui Agricultural University
基金
农业科技成果转化资金项目(2013C3008002)资助
关键词
水稻秸秆
低温等离子体
预处理
糖化率
rice straw
low temperature plasm
pretreatment
enzymatic saccharification
