童鞋论文网提供论文发表、论文查重以及本科论文写作、硕士论文写作、职称论文写作、毕业论文写作指导服务,上万成功案例,欢迎咨询。 网站地图  |  加入收藏  |  设为首页
童鞋论文网
热门搜索
行政 教育 营销 法律 经济 护理 心理 会计 文学 工商 计算机 旅游
站内搜索:
童鞋论文网
 当前位置:童鞋论文网 > 硕士论文 > 文章正文
 
生漆相结构与干燥机理及漆酶糖链结构探讨
论文作者:童鞋论文网  论文来源:www.txlunwenw.com  发布时间:2020/11/18 14:41:04  

摘要:合成涂料是当今涂料行业的主要产品,但合成涂料尤其是溶剂型合成涂料在使用过程中会释放大量的挥发性有机物(VOCs)而对环境造成严重污染。因此,发展绿色环境友好涂料成为了当下涂料行业的热点。生漆是我国的特产资源,是一种在我国使用了几千年的绿色环保涂料,其性能优异,被誉为“涂料之王”。然而因其产量较低而限制了其广泛应用。

论文以生漆为原料,采用柱层析分离纯化生漆中的各组分,并采用这些组分组合来研究其相结构,利用NMR和ESR来探究其干燥机理,同时采用质谱等方法解析了漆酶的糖链结构,以期为发展绿色环保的仿生生漆涂料提供理论支撑。主要研究结果如下:

(1) 采用丙酮沉淀及CM Sephadex C50和DEAE Sephadex-A50等柱层析方法相结合,分离纯化获得漆酚、漆酶、星青素、漆多糖及水不溶性糖蛋白,其中漆酶纯度高且其活性高达37364U/g。

(2) 通过高速离心分离和丙酮沉淀等方法相结合确定了水不溶性糖蛋白既存在于漆酚油相也存在于两相的界面层;采用分离获得的生漆各组分制备了各种乳液,考察它们的稳定性,确定了生漆的相界面由漆酚、漆酶-漆酚复合物、星青素-漆酚复合物和水不溶性糖蛋白构成。

(3) 通过研究各种乳液和生漆的干燥性能以及1H NMR和ESR跟踪漆酚的聚合过程确定了水不溶性糖蛋白和星青素在生漆干燥中的作用。在生漆的干燥过程中,水不溶性糖蛋白起介导电子迁移的作用。自由基在相界面层由漆酶催化氧化漆酚产生后,通过水不溶性糖蛋白迁移到漆酚油相引发油相中的漆酚聚合。而星青素则起抑制界面层酚氧自由基浓度和某些自由基产生的作用。这使界面层漆酚不优先聚合,O2因而能持续渗透进入生漆的水滴中氧化还原的漆酶,从而实现自由基持续产生和本体中漆酚的平稳聚合。

(4) 漆酶经胰蛋白酶消化后采用专一性酶PNGase F切除N-聚糖,采用还原消除法脱下O-聚糖,经分离纯化后对聚糖进行甲基化和乙酰化或全甲基化后采用GC-MS、MALDI-TOF-MS和UPLC-MS来解析其糖链结构。研究阐明了漆树漆酶的12条N-糖链和11条O-糖链的结构。

关键词:生漆;相结构;干燥机理;漆酶;糖链快捷检索

Abstract: Nowadays, synthetic coatings are the main products in the coating industry, but it will release a large amount of volatile organic compounds (VOCs) during the process of using, which will cause serious environmental pollution. Therefore, the development of green environment-friendly coatings has become a hot spot in the coating industry. Raw lacquer is a special resource in our country. It is a kind of green environmental protection coating which has been used for thousands of years in China. It has excellent performance and is known as the "king of coatings". However, its low output limits its wide application.

In this paper, the components in raw lacquer were separated and purified by column chromatography, and their combination was used to study the phase structure. NMR and ESR were used to explore the drying mechanism. Mass spectrometry was used to analyze the sugar chain structure of laccase. The study hopes to provide theoretical support for the development of green and environmental friendly bionic lacquer coating. The main results are as follows:

(1) Urushiol, laccase, stellacyanin, lacquer polysaccharide and water-insoluble glycoprotein were isolated and purified by acetone precipitation and column chromatography of CM Sephadex C50 and DEAE sephadex-A50. Laccase has high purity and its activity is as high as 37364U/g.

(2) By the combination high-speed centrifugation and acetone precipitation, water-insoluble glycoproteins were found not only in the interphase layer but also in the urushiol oil phase. Various emulsions were prepared from the raw lacquer fractions obtained by separation, and their stability was investigated. It is determined that the phase interface of the raw lacquer is composed of urushiol, laccase-urushiol complex, stellacyanin -urushiol complex and water-insoluble glycoprotein.

(3) The effects of water-insoluble glycoproteins and stellacyanin in the drying of raw lacquer were determined by studying the various emulsions and the drying properties of raw lacquer, as well as 1H NMR and ESR to track the polymerization process of urushiol. In the drying process of raw lacquer, water-insoluble glycoprotein plays a role in mediating electron transfer. After the free radicals are catalyzed by laccase to oxidize urushiol in the phase interface layer, they transfer to the urushiol oil phase through the water-insoluble glycoprotein to initiate urushiol polymerization in the oil phase. However, the stellacyanin can inhibit the concentration of phenoxy radicals and the production of some radicals in the interface layer. This makes the interfacial layer urushiol not preferentially polymerized, and O2 can continuously penetrate into the redox laccase in the water droplets of the raw lacquer, thus achieving the continuous production of free radicals and the stable polymerization of urushiol in the bulk.

(4) Laccase was digested with trypsin, and the N-glycans were removed by the specific enzyme PNGase F, and the O-glycans were removed by the reduction elimination. After purification, the glycans were methylated, acetylated or methylated, and then its sugar chain structures were analyzed by GC-MS, MALDI-TOF-MS and UPLC-MS. The study clarified that the laccase had 12 N-sugar chains and 11 O-sugar chains.

Key words: Lacquer; Phase structure; Drying mechanism; Laccase; Sugar chain

上一篇:基于生成对抗网络的行人重识别探讨     下一篇:不同种类活性炭对CX3R型消毒副产物的吸附探讨
 
论文客服 95702844
论文热线18796337551
本站网址 www.txlunwenw.com
郑重承诺 原创,包修改,包通过!
童鞋论文网真诚欢迎新老客户的光临与惠顾!
 
 热门文章
· 住宅建设用地使用权续期研究
· 用户锁定效应视角下的网易云音
· 众筹产品创新性对融资绩效的影
· 南京市城镇居民冷鲜肉认知度问
· 摩拜共享单车可持续盈利研究
· 催生地方政府隐性债务风险的原
· 基于网络平台的SPA模式研究——
· 社交媒体中不实信息转发主体心
· 基于游客感知的云台山景区微信
· 新媒体时代背景下乡村旅游企业
 
 推荐文章
· 论消费者民族中心主义对大学生
· 中端酒店的用户画像探讨——以
· 广州市花都区市场猪肉价格稳定
· 传播政治经济学视阈下对“吃播
· 顾客参与视角的休闲农业企业价
· 基于SCP范式的电商企业聚美优品
· 环境保护税税收优惠制度实施效
· 网络诽谤的刑法规制研究
· 拜仁慕尼黑足球俱乐部的中国粉
· 共享经济下成都大学生闲置物品
 
 相关文章
· 非国家行为体的影响及其限度研
· 雷蒙德·威廉斯的生态社会主义
· 麦金太尔正义理论思想渊源研究
· 论做好硕士研究生的引路人
· 新时期研究生学术活动研究
· “石发”与文学创作之关系研究
· 我国男装奢侈品消费市场探讨
· 关于张家山汉简所显示的汉初法
· 旅客冲击跑道事件的法律评析
· 离不了婚的新郎——我国婚姻登

论文原创,准时交稿,包修改,包通过,十年信誉,品质保证
童鞋论文网提供本科论文、专科论文、毕业论文、职称论文、硕士论文写作指导以及论文发表、论文查重服务
备案号:苏ICP备11011187号-1 苏公网安备32030502000117号
版权归童鞋论文网所有 禁止一切商用盗用