稻草秸秆的酶解糖化及发酵生产衣康酸  

Enzymatic Saccharification of Rice Straw and Itaconic Acid Production by Fermentation

作　　者：刘兰[1] 倪赛 任雨萍 由维清[1] 印培民[1] LIU Lan;NI Sai;REN Yuping;YOU Weiqing;YIN Peimin(Institute of Microbiology,Jiangxi Academy of Science,Nanchang 330000,China;Jiangxi Keyuan Bio-Material Co.,Ltd.,Nanchang 330000,China)

机构地区：[1]江西省科学院微生物研究所,江西南昌330000 [2]江西科院生物新材料有限公司,江西南昌330000

出　　处：《化学与生物工程》2020年第4期51-57,共7页Chemistry & Bioengineering

基　　金：江西省科技支撑计划项目(20181BBG70053);江西省科学院重大科研项目(2016-YZD1-02)。

摘　　要：以稻草秸秆酶解糖化液为原料,利用土曲霉KY-013发酵生产衣康酸;研究了超微粉碎、高温蒸煮、稀硫酸和NaOH溶液等预处理方式对稻草秸秆酶解糖化的影响。确定稻草秸秆的最佳预处理方式为:按固液比1∶7.5(g∶mL)加入质量分数为1.5%的NaOH溶液,于30℃、200 r·min^-1振荡处理24 h;最佳酶解工艺为:按固液比1∶20(g∶mL)加入pH值4.8的柠檬酸缓冲液,加入2.5 IU·g-1纤维素酶溶液,于50℃、200 r·min^-1酶解48 h。在此条件下,还原糖转化率达到最高,为82.51%。在不添加葡萄糖和木糖条件下,酶解糖化液中葡萄糖浓度为30 g·L^-1、木糖浓度为3.5 g·L^-1时,衣康酸产量达到最高,为9.78 g·L^-1;在额外添加葡萄糖和木糖条件下,随着外源葡萄糖和木糖浓度的增加,土曲霉KY-013对酶解糖化液的利用效率逐渐升高,衣康酸产量最终达53.88 g·L^-1。本研究为衣康酸工业化原料找到了非粮替代品,也为生物发酵行业碳源的原料供应提供了新的途径。Using enzymatic saccharification liquid of rice straw as raw material,we produced itaconic acid by fermentation of Aspergillus terreus KY-013.Moreover,we studied the effects of pretreatment methods such as superfine pulverization,high temperature cooking,dilute sulfuric acid,and sodium hydroxide on enzymatic saccharification of rice straw.The optimal pretreatment method of rice straw is determined as follows:1.5%NaOH solution is added according to the solid-liquid ratio of 1∶7.5(g∶mL),and then the rice straw is vibrated for 24 h at 30℃and 200 r·min^-1;the optimal enzymolysis process is determined as follows:2.5 IU·g-1 cellulase solution is added into citric acid buffer with pH value of 4.8 according to the solid-liquid ratio of 1∶20(g∶mL),and enzymolysis for 48 h at 50℃and 200 r·min^-1.Under above conditions,the conversion rate of reducing sugar reaches the highest of 82.51%.Under the condition of no-adding glucose and xylose,when the glucose concentration is 30 g·L^-1 and the xylose concentration is 3.5 g·L^-1,the production of itaconic acid reaches the highest of 9.78 g·L^-1;under the condition of adding glucose and xylose,with the increase of glucose and xylose concentrations,the utilization efficiency of Aspergillus terreus KY-013 to enzymatic saccharification liquid increases gradually,and the production of itaconic acid finally reaches 53.88 g·L^-1.In this study,non-food substitutes used for itaconic acid industrial raw materials are found,providing a new way for the supply of carbon sources in the fermentation industry.

关 键 词：稻草秸秆 酶解糖化 纤维素酶 土曲霉 衣康酸 

分 类 号：TQ352[化学工程] TS721[轻工技术与工程—制浆造纸工程]