棉纤维伴生物和棉纺织品的酶精练(待续)

棉纤维的伴生物有果胶质、蜡质、含氮物质、灰分等,它们的存在会影响棉纺织品印染成品的质量,必须在染整加工前处理过程中加以去除,酶精练是一种绿色、环保的前处理过程.介绍了棉纺织品酶精练剂的主要组分——角质酶和果胶酶,并举例说明了角质酶和果胶酶在棉精练中的应用效果.     

苎麻酶-化学联合脱胶工艺优化

为了减轻苎麻化学脱胶造成的环境污染,提高苎麻纤维可纺性能,采用酶化学联合脱胶法进行苎麻脱胶,分析酶脱胶过程中pH值、浴比、酶用量、金属离子、温度和时间对苎麻脱胶的影响,同时对浴比、酶用量、温度和时间进行4因素3水平的正交试验,采用优化后的工艺对苎麻进行酶脱胶、化学精练和漂洗。结果表明,苎麻在用KDN果胶酶第1步脱胶(浴比为1∶12,pH值为8.6,1 mmol/LMg2+,KDN果胶酶300 IU/g,45℃、4 h),TZ-888复合酶第2步脱胶(浴比为1∶18,pH值为4.0,1 mmol/L Ca2+,TZ-888复合酶500 IU/g,40℃,5 h)后残胶率为14.14%,进行化学精练和漂洗后最终残胶率为1.79%。     

珍珠纤维/棉混纺针织物生物酶精练工艺研究

采用生物酶对珍珠纤维,棉混纺针织物进行精练.分别用液体果胶酶、固体果胶酶、精练酶等对织物进行精练,变化酶用量、处理温度、pH值等因素,对织物毛效、失重率、白度等指标进行评定.结果表明:3种酶有相似的处理条件,如最适pH值和最适温度,但影响程度各异.综合精练效果分析,精练酶效果最好.探索了各种酶复配是否具有协同效应,结果表明:果胶酶去除果胶,有利于织物白度的提高;精练酶对织物毛效有提高作用.精练酶1.0%与液体果胶酶0.5%复配后的综合效果较好,毛效为16.0 cm/30 min,失重率为7.00%,漂后白度达85.5%另外,使用复合酶完成珍珠纤维/棉的精练过程可以达到比碱精练工艺更好的效果.     

棉织物酶法轧堆精练工艺及处理效果北大核心

测试了精练酶BioPrep^(■)Fusion和碱性果胶酶的酶学特性,并对棉织物进行冷轧堆精练处理。通过测试毛细效应、润湿时间和果胶去除率,比较了不同的果胶酶冷堆精练工艺对棉织物处理效果的影响。再将不同果胶酶冷堆精练处理后的织物进行轧蒸氧漂与染色,并与碱法冷堆精练-轧蒸氧漂前处理效果对比。结果表明,精练酶BioPrep^(■)Fusion精练效果较好,当酶质量浓度为6 g/L时,冷堆精练后和轧蒸氧漂后的果胶去除率分别为85.7%和93.3%,毛细效应分别为10.9 cm和11.5 cm,润湿时间均小于5 s。     

亚麻织物的生物酶精练工艺

分别采用果胶酶、精练酶301L以及精练酶301L与中性纤维素酶复配工艺对亚麻织物进行精练前处理,通过测试处理后织物的性能,优选出最佳应用工艺,并与传统碱精练工艺进行对比,结果表明,酶精练后织物基本能达到碱精练的效果,且具节能、环保、设备简单、工艺流程短等优点。     

棉织物果胶酶精练工艺研究

采用国产果胶酶对棉织物进行精练,分析了pH值、时间、温度、浓度、激活剂等因素对酶精练效果的影响.采用正交实验优化棉织物果胶酶精练工艺,最佳工艺条件为:酶浓度9g/L,pH值8;温度50℃,时间60 min.比较了经不同精练工艺处理的棉织物的白度、断裂强力和毛效.     

角质酶和果胶酶复合酶对棉针织物的精练研究

分别用角质酶、果胶酶、角质酶/果胶酶复合酶对棉针织物进行精练,考察精练前后纤维表面形态以及果胶去除率、棉蜡去除率、强力、润湿性变化.结果表明:角质酶(1 500 U/L)/果胶酶(12.75 U/L)复合酶的果胶去除率、棉蜡去除率分别达到79.1%和43.0%,比单独使用果胶酶有所提高,说明两种酶对棉纤维的精练具有一定的协同作用.     

芽孢杆菌产碱性果胶酶的棉散纤维精练

采用自制的芽孢杆菌WSHB04202产碱性果胶酶对棉散纤维进行精练,与Bioprep 3000L果胶酶和传统碱精练进行对比,分析了自制酶对棉纤维失重率、果胶去除率、棉蜡去除率、断裂强力及染色性能的影响.结果表明,自制酶与Bioprep 3000L果胶酶的应用效果相当,酶精练后棉纤维的失重率和强力损失远小于碱精练,棉蜡去除率低于碱精练,果胶去除率及精练后棉纤维的染色性能与碱精练试样相当.     

棉织物染整中不同果胶酶精练效果的比较研究

通过试验得出果胶酶应用的较佳工艺条件:酸性果胶酶A pH值3～5,温度30～60℃;碱性果胶酶B pH值7～9,温度40～60℃.在此工艺条件下比较2种酶的精练效果,并测定2种果胶酶酶活、SDS-PAGE电泳等,分析研究了它们的精练特点.结果表明:碱性果胶酶B分子质量小,酶的专一性更强,对棉纤维果胶物质去除具有较好的效果[碱性果胶酶B 0.025%(owf),JFC 0.2 g/L,果胶去除率70%].     

纯棉针织物酶练工艺的在线监测

采用紫外分光光度法测定棉针织物果胶酶精练体系中酶活和果胶裂解产物不饱和半乳糖醛酸的含量,讨论了温度、pH值、助剂和酶浓度对精练浴酶活和酶裂解产物量的影响,研究了酶精练液的重复利用性;并通过监测生物酶精练工艺过程,了解和控制酶精练的效果,建立了快速监测的初步模型.     

Dependence of reactive prints of cotton fabrics on type and condition of the scouring system

The effect of scouring systems, i.e. bioscouring and conventional scouring, of cotton fabrics on the printability of the latter by a reactive dye was studied. Parameters affecting the bioscouring process, namely concentration of alkaline pectinase enzyme in single use and in admixture with cellulase enzyme and duration of bioscouring process as well as pretreatment with β‐cyclodextrin at different concentrations followed by bioscouring on the printability, were also studied. The printed substrates, obtained with fabrics that have been bioscoured under those conditions along with fabric conventionally scoured using sodium hydroxide, were evaluated for colour strength, handle and overall fastness properties to washing, rubbing and perspiration. Results obtained bring into focus the most appropriate bioscouring conditions of cotton fabric for optimal printability. Fabrics processed according to the most appropriate conditions of bioscouring exhibit overall printing characteristics which are comparable with, if not superior than, those obtained with conventional scouring. Prints obtained with bioscouring using alkaline pectinase and cellulase enzymes exhibit K/S of 19.77; this is compared with K/S of 18.35 for conventional scouring. This is in addition to replacing the harsh chemicals with eco‐friendly biodegradable enzymes.     

EFFECT of ENZYMES ON MICROFILTRATION of APRICOT PUREE1

In pilot plant flitration tests, using a ceramic microfilter, it was shown that pectinase was effective in increasing flux at an enzyme level as low as 75 ppm and that flux increased with time during filtration. Cellulase was shown to inhibit flux when used alone or in combination with pectinase, even though it contributed to reducing viscosity of the puree. Both cellulase and pectinase were partially held back by the filter; usually more than half the pectinase was retained. This resulted in increased enzyme concentration with time in retentate. Retained enzymes might be used by continuously adding fresh puree with reduced enzyme to retentate after startup.     

棉针织物复合生物酶精练加工

为进一步提高单一酶对棉织物的精练效果,复合生物酶精练日益受到重视。但由于不同酶制剂最佳工作条件的不一致,使复合酶精练受到极大限制。为此,研究了自制碱性果胶酶、中性纤维素酶、中性碱性蛋白酶和自制木聚糖酶及其组成的复合生物酶制剂的棉针织物一浴一步法精练加工工艺,确定了最优精练组合。结果表明,复合酶的精练效果较单一酶有明显的提高,织物润湿性、染色性能接近常规碱精练水平且强力损失更小。     

新型碱性果胶酶用于棉针织物精练的工艺优化

针对芽孢杆菌Bacillussp.WSHB04-02所产碱性果胶酶在棉织物精练中存在的问题,研究该碱性果胶酶应用于棉针织物精练的工艺条件,并进行优化。利用单因素法考察pH值、温度、酶用量和处理时间4个因素对酶精练效果的影响,得出该碱性果胶酶用于棉针织物精练的最优工艺条件为:酶活浓度960 U/L(1.2 mL/L),pH值7.0,温度60℃,处理时间40 min。对利用优化工艺处理的棉针织物的织物失重率、毛效、果胶去除率进行测定,与国外公司的相关产品以及传统碱精练工艺的使用效果做了比较。结果表明,新型碱性果胶酶具有中性、耐热性较好、成本较低和环境污染少的优点。     

棉针织物碱性果胶酶精练时酶解产物的研究

通过测定棉针织物碱性果胶酶精练过程中产生的糖量变化研究了精练时间、酶用量及棉蜡对酶精练效果的影响,研究结果对碱性果胶酶在棉织物精练中的应用有一定的指导意义．     

动力学法优化碱性果胶酶比活的测定方法

本文通过优化蛋白浓度测定方法和酶活力测定方法,并以酶解动力学曲线考察方法优化的合理性,以验证终点法测定碱性果胶酶比活的准确性。结果表明,果胶酶蛋白的最佳测定波长为550 nm,其线性和截距明显优于传统方法,可以忽略果胶酶稀释倍数对蛋白测定的影响。钙离子对该酶具有激活作用;聚半乳糖醛酸比果胶更适合作为酶活力测定底物,其最适pH为9.5,最佳浓度为2 mg/mL,果胶酶活力测定的最佳波长为232 nm,所测酶活力在吸光度值0~2范围内均保持零级反应状态,酶蛋白浓度与酶解速率线性相关且回归曲线截距更接近原点,因此,该测定条件不仅可用于终点法,酶解时间也可灵活掌握,而非拘泥于一个固定的时间段。以酶解30 min为例,其检测限(LOD)为0.15 mU/mL。由于DNS法的灵敏度较低,其半乳糖醛酸标准曲线不过原点,从而导致因酶液稀释倍数不同而产生测量误差,因此,紫外法测定碱性果胶酶活力为最佳选择。     

低甲醛美耐敏树脂单宁Unitan KDN的应用

Unitan KDN是以美耐敏树脂构成的低甲醛鞣剂，通常可在复鞣阶段与其他阴离子产品一同使用。鞣制的皮革中甲醛含量低至57．466mg／kg，已低于国家出口皮革中甲醛含量不超过70mg／kg的要求，它非常适合用于甲低甲醛皮革的复鞣。并可使皮革粒面紧实，对皮革纤维结构较为松弛的部位如肩部，边腹部有好的填充作用，经Unitan KDN美耐敏树脂鞣制的皮革可获得柔软、丰满的手感。其ATOMA系列加脂剂耐水溶液萃取性极好。     

生物酶应用于棉/麻混纺织物前处理的研究

用α-淀粉酶、果胶酶、纤维素酶的复合酶处理棉麻混纺织物，对酶煮氧漂工艺参数进行优选，并和常规碱处理工艺进行比较，该工艺具有降低成本，保护环境的优点，可提高半成品质量。     

Improvement of tea leaves fermentation with Aspergillus spp. pectinase

The pectinase enzymes isolated from Aspergillus spp., A. indicus, A. flavus and A. niveus were used for fermentation of tea leaves. The enzymes were purified and characterized. The effect of both crude enzyme preparation and purified pectinase enzymes on the improvement of tea leaf fermentation were determined in terms of theaflavin, thearubigin, high polymerized substances, total liquor colour, dry matter content and total soluble solids of the tea produced. The crude enzyme preparations obtained from ethanol precipitation were found to be more effective in improving tea leaf fermentation than the purified pectinase enzymes.     

果胶酶在亚麻纱前处理中的应用

采用碱性果胶酶代替碱对亚麻纱进行精练,通过正交试验,确定了碱性果胶酶精练的最佳工艺条件,分析了影响碱性果胶酶对亚麻纱精练的因素.实验证明在较低的温度下采用碱性果胶酶进行精练,与常规的高温碱精练工艺相比,果胶去除程度高,润湿性好,白度相当,可节约能源,减少环境污染.