论文总字数：15973字

摘 要

玉米芯，即玉米去粒之后的穗轴，其中含有大量的半纤维素，且来源广泛，过去多作废弃物处理，用来焚烧，不仅污染环境，而且也很大程度地浪费了资源，所以怎样有效的利用玉米芯来提取半纤维素显得迫在眉睫。很多文献已报道木聚糖具有多种与生物有机体自身免疫防御和氧化保护相关的生物学活性。其硫酸酯衍生物亦因此广泛的生物活性和更好的水溶性而受到人们极大的关注。本文主要提及木聚糖硫酸酯。

本实验对玉米芯中半纤维素的提取方法是碱氧化法，对其进行粗提取，然后通过离心，用70%乙醇洗涤，再通过透析袋透析进行纯化。我们主要从温度、pH值，提取时间等三个条件对其提取进行优化，通过对提取物纯化之后的成分进行红外光谱和液相色谱以及¹H和¹³C-NMR图谱等数据分析，得到其成分数据和我们所需产物的得率。木聚糖是半纤维素的主要成分，它经木糖以β-1,4糖苷键连接而成，通过酶水解可生产低聚木糖、木糖等疗效食品，这些产品在国际上需求很广。

本文利用微反应器的优良特性，在微通道反应器中进行玉米芯木聚糖的磺化反应，生成木聚糖硫酸酯。然后通过红外光谱和¹³C-NMR图谱对其进行结构和元素分析，最后得出结论。

关键词：玉米芯木聚糖 碱氧化法提取半纤维素 微通道技术 木聚糖硫酸酯

Microchannel technology for efficient preparation of xylan sulfate

Abstract

The corn cob, the cob after corn grain removal, contains a large amount of hemicellulose and has a wide range of sources. In the past, it was often used as a waste material for incineration. It not only pollutes the environment, but also wastes resources to a great extent. How to effectively use corn cob to extract hemicellulose is imminent. Many literatures have reported that xylan has a variety of biological activities related to the autoimmune defense and oxidative protection of biological organisms. Its sulphate derivatives have also received great attention due to their extensive biological activity and better water solubility. This article mainly mentions xylan sulfate.

In this experiment, the method for extracting hemicellulose in the corn cob was alkali oxidation, which was subjected to crude extraction, followed by centrifugation, washing with 70% ethanol, and purification by dialysis bag dialysis. We mainly optimize the extraction from three conditions: temperature, pH value, and extraction time. The composition of the extracted components was analyzed by IR, LC and 1H and 13C-NMR spectra. And the yield of our desired product.Xylan is the main component of hemicellulose it by xylose in beta 1, 4 glycosidic bond connection, through enzymatic hydrolysis to produce low poly xylose xylose curative effect such as food, these products demand is very wide in the world .

This paper USES the excellent characteristics of micro reactor, the microchannel reactor for corn cob xylan sulfonation reaction, generate xylan sulfate Then by ftir and ¹³ C-NMR spectra and elemental analysis on the forming, the final conclusion.

Key words: Corn cob xylan;Alkaline extraction of hemicellulose;Microchannel technology;Xylan sulfate

目 录

摘 要 I

Abstract II

第一章 文献综述 1

1.1 研究背景 1

1.2 微反应器的了解 2

1.3 玉米芯半纤维素的提取及条件优化 3

1.4 木聚糖的硫酸化修饰 3

1.5 本论文的研究意义和内容概括 4

第二章 实验过程 6

2.1实验试剂和实验仪器 6

2.1.1实验试剂 6

2.1.2实验仪器 7

2.2 实验步骤 9

2.2.1 半纤维素的提取： 9

2.2.2 半纤维素的纯化： 9

2.2.3 木聚糖的磺化： 9

2.3 数据分析方法 10

第三章 结果与讨论 12

3.1 不同优化条件下半纤维素得率 12

3.2 半纤维素红外光谱图 13

3.3 液相色谱分析 14

3.4 不同条件对所提半纤维素的分子量的影响 14

3.5 ¹H和¹³C-NMR谱图 15

第四章 结论与展望 17

4.1 结论 17

4.2 展望 18

参考文献 19

致 谢 21

请支付后下载全文，论文总字数：15973字