杨木联产低聚木糖和枯草芽孢杆菌的研究  

Co-production of Xylooligosaccharides and Bacillus subtilis from Poplar

作　　者：文沛瑶 游佳欣 徐勇[1] 张军华[1,2] WEN Peiyao;YOU Jiaxin;XU Yong;ZHANG Junhua(College of Chemical Engineering,Nanjing Forestry University,Nanjing 210037,China;College of Forestry,Northwest A&F University,Yangling 712100,China)

机构地区：[1]南京林业大学化学工程学院,江苏南京210037 [2]西北农林科技大学林学院,陕西杨凌712100

出　　处：《林产化学与工业》2021年第5期1-7,共7页Chemistry and Industry of Forest Products

基　　金：国家重点研发计划资助项目(2017YFD0601001);南京林业大学科研启动基金(163030103)。

摘　　要：采用乙酸(AC)水解杨木制备低聚木糖(XOS),然后探讨不同第二步预处理对乙酸水解杨木酶水解的影响,最后以酶水解液作为碳源进行发酵培养枯草芽孢杆菌。采用5%乙酸在170℃下预处理杨木30 min后,低聚木糖得率为55.8%。第二步预处理中,各种预处理对乙酸杨木酶水解改善效果的顺序依次是:乙酸-双氧水(HPAC)、NaOH、NaOH-H_(2)O_(2)、γ-戊内酯(GVL)、NH_(3)·H_(2)O预处理。乙酸水解杨木再经过乙酸-双氧水预处理后的纤维素酶的水解液中葡萄糖得率最高为72.4%。加入吐温80可以使乙酸和乙酸-双氧水(AC-HPAC)两步预处理的杨木酶水解液中的葡萄糖得率提升至93.8%。两步预处理得到的酶水解液经过11.5 h发酵后,培养的枯草芽孢杆菌按菌落形成单位(CFU)计数,菌体浓度最高可达2.1×10^(9) CFU/mL,此时酶水解中的葡萄糖利用率为95.3%,木糖利用率为25.0%。Acetic acid(AC)hydrolysis and the second-step pretreatment were used to produce xylooligosaccharides(XOS)and enzymatic hydrolysate from poplar.The hydrolysate was used as carbon resource to produce Bacillus subtilis by fermentation.After the poplar was pretreated by 5%AC at 170℃for 30 min,the XOS yield of the pretreatment liquor was 55.8%.In the second-step pretreatment,the order of improvement on enzymatic hydrolysis of AC-pretreated poplar was showed as follows:hydrogen peroxide-acetic acid(HPAC),sodium hydroxide,sodium hydroxide-hydrogen peroxide,γ-valerolactone(GVL),ammonia pretreatment.The AC-pretreated poplar after HPAC pretreatment had the highest digestiability and the glucose yield of the hydrolysate was 72.4%.Specially,Tween 80 could further improve the glucose yield of AC-HPAC-pretreated poplar to 93.8%.The enzymatic hydrolysate obtained from the two-step pretreated poplar was used to produce B.subtilis and the highest viable count of the fermentation liquor could reach 2.1×10^(9) CFU/mL.After fermentation for 11.5 h,the utilizations of glucose and xylose were 95.3%and 25.0%,respectively.The results in this work could guide for the co-production of XOS and B.subtilis from poplar,and provide a reference for the high value-added conversion of poplar.

关 键 词：杨木 预处理 低聚木糖 酶水解 枯草芽孢杆菌 

分 类 号：TQ35[化学工程]