超声辅助常温稀碱法分离玉米芯中半纤维素的研究  

Study on Isolation of Hemicelluloses from Corn Cob via Ultrasound-assisted Diluted Alkali Extraction

作　　者：方驹[1] 周雪松[1] 薛翠翠[1] 

机构地区：[1]华南理工大学制浆造纸工程国家重点实验室,广东广州510640

出　　处：《造纸科学与技术》2012年第5期26-30,共5页Paper Science & Technology

基　　金：国家高技术研究发展计划(863计划)重点项目(2007AA100704)

摘　　要：本研究通过先超声预处理再常温稀碱抽提的两步法,成功地由玉米芯中分离得到水不溶性半纤维素(HA)和水溶性半纤维素(HB),并探讨了在不同的碱浓度下超声预处理对获得的半纤维素的得率和结构的影响。结果表明,先经过10 min的超声预处理,再经3 h 5.0%KOH常温抽提得到半纤维素的得率与不经过超声预处理的20 h常温稀碱抽提大致相同,但采用前一种方法得到的水溶性半纤维素的得率较后一种方法大为提高。此外,离子色谱(IC)、凝胶渗透色谱(GPC)、傅里叶变换红外光谱(FT-IR)和核磁共振氢谱(1H-NMR)的表征结果表明,与传统稀碱抽提所得的半纤维素相比,经过短时间超声预处理和相同浓度的稀碱液抽提后,水溶性半纤维素中的阿拉伯糖含量更高,由此说明半纤维素分子链中更多的支化结构得以保留,而该结构的存在将对后续的改性反应更为有利。The water-soluble （HA） and water-insoluble （HB） hemicelluloses were successfully isolated from corn cob by a two step ultrasound-assisted diluted alkali extraction method. The yield and the structural features of the hemicelluloses obtained from the two step extraction processes under different alkali concentration during the uhrasound pretreatment were investigated. The results showed that the yield of a short time ultrasound treatment followed by a 3h diluted alkali extraction was almost the same as that obtained by a 20h conventional diluted alkali extraction. Moreover, with an assistance of the ultrasound pretreatment, larger amount of water-soluble hemicelluloses were successfully isolated from corn cob. From the characterization results of IC, GPC, FT - IR and 1 H - NMR, it can be seen that the water-soluble hemicelluloses obtained from this method have higher content of arabinose when comparing to those isolated via conventional alkali extraction method, which implied that such highly branched structure could endow them with better water solubility. Although a certain degree of the degradation of the hemicelluloses may be happened during this process, the original highly-branched structure of this natural polymer could be retained well and therefore, the biopolymer with such structure is supposed to be favorable to the following modification and utilization.

关 键 词：半纤维素 玉米芯 超声抽提 聚木糖 

分 类 号：TS721[轻工技术与工程—制浆造纸工程]