摘要阿拉伯木聚糖是大麦细胞壁的主要结构多糖,也是大麦籽粒中非淀粉多糖(NSP)的重要组分之一,其含量、结构以及理化性质不仅影响大麦的品质,也对大麦在啤酒酿造、饲料加工等方面的利用价值有重要影响。本实验通过测定并比较分析20种西藏野生大麦及栽培大麦品种的总阿拉伯木聚糖含量及木聚糖酶活力,从而能对野生大麦的相关品质及遗传特性有更深入的了解,并为西藏野生大麦丰富的遗传资源的开发、利用提供重要的参考依据。实验结果表明,不同品种大麦的总阿拉伯木聚糖含量及木聚糖酶活力具有显著差异,但分布较为均匀,且西藏野生大麦的总阿拉伯木聚糖含量及木聚糖酶活力均普遍高于栽培大麦。这将有利于我们在此基础上通过杂交等手段获得具有新的遗传特性的优良大麦品种,并能进一步促进啤酒等工业的发展。47352
Abstract Arabinoxylan is a major polymer in cell wall of barley and an important component of non-starch polysaccharide(NSP) barley grain, it’s content, structure and the physical and chemical properties affect not only the quality of barley but also it’s utilization in beer brewing, feed processing and so on. In this study, we determined and analysed the total arabinoxylans content and endo-xylanase activity in the 20 kinds of Tibetan wild barley and cultured barley to learn more about the quality and genetic characteristics of wild barley and to provide the important and scientific reference basis for the development and utilization of genetic resources of wild barley in Tibetan. The results show that the total arabinoxylan content and xylanase activity of different varieties of barley are obviously different and the distribution is successive.Furthermore, the total arabinoxylan content and endo-xylanase activity of Tibetan wild barley are generally higher than those of cultivated barley. This study result can help us to acquire excellent barley species through the hybridization and other biological technique and will promote the development of beer industry.
毕业论文关键词:野生大麦;栽培大麦; 总阿拉伯木聚糖含量;木聚糖酶活力
Keyword: wild barley; cultivated barley; the contents of total arabinoxylans; endo-xylanase activity
目 录
1 引言 4
2材料与方法 4
2.1大麦品种、种植地选定 4
2.2材料的获得与处理 4
2.3实验仪器与药品 5
2.4实验方法 5
2.4.1 Total AX测定(Douglas 间苯三酚法) 5
2.4.1.1 TAX的提取 5
2.4.1.2显色剂的配制 5
2.4.1.3木糖标准曲线的制备 5
2.4.2 大麦内切木聚糖酶(Endo-xylanase)活力测定(DNS试剂法) 5
2.4.2.1全麦粉粗提酶 5
2.4.2.2木糖标准曲线的制备 5
2.4.2.3 内切木聚糖酶活力的测定 5
3 结果与分析 6
3.1 TAX含量的测定 6
3.2内切木聚糖酶活力的测定 7
4 讨论 9
参考文献 10
致谢 11
1 引言
阿拉伯木聚糖(AX)是大麦非淀粉多糖的主要成分,同时也是其细胞壁多糖的重要组成部分。大麦阿拉伯木聚糖在大麦中所占的含量并不高,一般占种子干重的3%-5%左右。但由于AX具有高粘度、高吸水性等特性,其含量、结构及理化性质对大麦品质以及大麦最终的利用价值均具有重要影响,如能影响种子的吸水性、提高麦粒硬度及阻碍大麦籽粒胚乳营养物质的释放等[1]。另外,在制麦时降解不充分的AX进入麦芽汁后会增加麦汁的黏度,阻碍麦汁及啤酒的过滤,最终造成成品啤酒的浑浊,恶化啤酒泡沫,影响啤酒口感[2-3]等。 因此,大麦阿拉伯木聚糖的功能性质受到越来越多的国内外学者的关注。