【作者】 孙燕华；

【导师】 赵吉； 孙建光；

【作者基本信息】 内蒙古大学 ， 环境科学， 2009， 硕士

【摘要】 亚麻纤维作为一种重要的纺织原料,深受人们的喜爱。关于亚麻纤维的脱胶方法有物理脱胶法、化学脱胶法和生物脱胶法。目前应用和研究较多的是生物脱胶方法。生物法又分为微生物脱胶和酶法脱胶。目前国内外对亚麻脱胶研究较多的是微生物脱胶和酶法脱胶。本论文在实验室条件下对亚麻脱胶的相关参数和几个影响因素进行了相关的研究,通过测定脱胶酶的活性来分析对亚麻脱胶的影响;筛选出了四株高效脱胶菌并做了鉴定,对脱胶菌的产果胶酶活性影响因素做了相关性的研究;提取亚麻发酵液用DGGE的方法研究了不同条件下脱胶微生物的多样性。主要研究结果如下:1.在亚麻脱胶的过程中,微生物活菌数在脱胶前期迅速升高,后期下降;脱胶酶果胶酶、纤维素酶和木聚糖酶起着重要作用,果胶酶含量明显高于其他两种酶活性;含氮量和还原糖在脱胶前期都迅速增加,脱胶过程中微生物利用碳源,还原糖含量在波动中稍有下降,总氮在波动中有所上升;pH值前期迅速下降,后期趋于稳定;脱胶过程中,COD一直在升高,前期增长迅速,后期缓慢。在脱胶影响因素中,选择温度,水浴比,pH值和脱胶助剂。在温度为35℃时,水浴比在1:20左右,pH在6或8,脱胶效果较好,脱胶酶活性较高。加入尿素的脱胶助剂相对加入其他助剂和不加的果胶酶活性较高,加入硝酸铵的相对于其他的木聚糖酶活性较高。2.土壤基质中含有丰富的微生物,亚麻脱胶时加入不同土壤基质,筛选出50多株脱胶菌,又通过复筛的方法,从中筛选出4株脱胶效果相对较高的脱胶菌,对4株脱胶菌进行了基因序列测序和生理生化的测定,初步鉴定GJ-87-1、GJ-87-2和GJ-87-3为芽孢杆菌属,GJ-86-6为类芽孢杆菌属的一个种。对4株菌进行了亚麻脱胶的应用研究,测定了脱胶液中的相关酶活性,结果发现,加菌脱胶之后脱胶液中的果胶酶和木聚糖酶活性显著增高,纤维素酶活性较低。符合亚麻脱胶用菌的要求。测定了脱胶液中其他相关参数,还原糖,总含氮量、pH值和脱胶率等。测定结果发现,加菌之后还原糖变化不太显著,总含氮量明显增高,脱胶率提高,pH略显碱性。3.对4株高效脱胶菌产酶活性的影响因素温度、pH值、碳源、氮源和金属离子做了相关性的研究。在35℃左右,脱胶菌产果胶酶活性最高;在底物偏酸性的环境下,果胶酶活性相对较高;对于碳源的影响,在加入麸皮和豆粉的培养基中,果胶菌产果胶酶活性相对较高;在氮源加入硫酸铵时,果胶菌产酶活性相对较高;不同金属离子对4株脱胶菌的产酶活性影响各不相同。4.从亚麻发酵液提取不同时间段发酵液中的细菌总DNA,应用PCR-DGGE技术,分析了亚麻发酵液中的微生物多样性的的动态变化,结果发现亚麻发酵前期(24h左右),发酵液中的微生物多样性较高,之后至亚麻发酵结束,细菌微生物多样性变化不大,多样性相对较稳定。对于四种不同处理的亚麻发酵,结果发现不同处理亚麻发酵液中微生物多样性有很大不同,通气的亚麻发酵液中细菌微生物多样性相对较高,加入尿素之后微生物多样性明显减少,加入细菌GJ-86-6之后微生物多样性中出现明显优势菌群。更多还原

【Abstract】 Flax is a very important textile raw material and is popular with people. There are three mainly methods of flax degumming, physical, chemical and biological. At present biological flax degumming is the main using and investigative method. biological flax degumming includes adding bacterium and adding enzyme. In this thesis It has investigated correlation parameter and factors of flax degumming in lab conditions analyse the flax degumming factors with determining enzyme activity. they have filtered some bacteria of efficient flax degumming and made the identification. they have investigatived the influence factors of degumming bacteria’s pectinase activity. they also investigatived the microorganism diversity at different conditions of flax degumming using DGGE method. The main results are as follows:1. At the process of flax degumming, The amount of alive bacterium goes up at the prophase and falls at the anaphase. Pectinase, cellulose and xylanase are very important and have effects on flax degumming, The content of pectinse is higher than two others. The quantity of nitrogen and reducing sugar are rapidly increasing at the prophase of flax degumming. In the falx degumming process microorganism utilize carbon. The content of reducing sugar decrease and the content of nitrogen increase among the fluctuation. pH has a sharp deline in the prophase and becomes stabilization in the anaphase. COD has a sharp increase in the prophase and has a slowness increase in the anaphase.Among the influence factor, wo choose temperature, ratio of flax stem to water,pH and degumming additive to investigate. The optimum erternal retting conditions were as follows:water temperature 35℃, ratio of flax stem to watel:20 and pH 6 or 8. The activity of pectinse is higher. Adding urea into rettng water has higher activity of pectinse than adding others and adding none. The activity of xylanase is higher with adding ammonium nitrate then others .2. There are abundant microorganism in the soil. When flax were retting, we added diffent type of soil into the retting water and more then 50 bacteria were screened from them. Four bacteria with higher flax retting effect were chose from them. In order to identify their category we determined their gene sequence. They were preliminarily identified and GJ-87-1, GJ-87-2,GJ-87-3 were named as Bacillus. GJ-86-6 were named as Paenibacillus massiliensis. We added these four bacteria into flax stem respectively and added water to ret, then determined interrelated enzyme. The result were that when we added bacteria we fond the activity of pectinse and xylanase observably increased and activity of cellulose was low in retting water. They conformed to the require of degumming bacteria. We also determined others interrelated parameter reducing sugar,nitrogen,pH and ratio of flax stem degumming. The result were as follows: when we added bacteria into retting water the reducing sugar has no remarkable change, the content of nitrogen has a sharp increase, the ratio of degummed flax stem increased and pH showed alkalescence.3. We investigated the influencing factors to the activity of pectinse about the four bacteria temperature, pH, carbon, nitrogen and metal ion. The pectinse’s activity of bacteria was higher at 35℃than others; The pectinse’s activity of bacteria was comparatively higher when the substrat was at acid condition; To carbon origin, the activity of pectinse was higher when we added bran and pulse flour than others ; Adding ammonia sulfate, the activity of pectinse was higher than adding others; Different metal ion has different effect to the activity of pectinse about the four bacteria.4. We extracted DNA of bacteria from the retting water at different time and use PCR-DGGE method to investigated dynamic change of microorganism diversity in the retting water. The result was that microorganism diversity of the retting water was higher at prophase than at other time(at about 24 hours), then the microorganism diversity was steady until flax retting finished. When we used four methods to deal with the flax degumming, the resulst of microorganism diversity about the retted water were very different. Microorganism diversity is higherthan others when we added oxygen to the retting water . when we added urea into the retting water the microorganism diversity decreased. There were dominant population when we added GJ-86-6 to the retting water.更多还原