酸性纤维素酶与靛蓝染色织物吸附性能的研究

研究了酸性纤维素酶对靛蓝染色织物的吸附性能,试验表明酶在纤维表面呈多分子层吸附。同时也研究了pH值、靛蓝染色深度和表面活性剂对吸附性能的影响。纤维素酶在pH值为4．88时的吸附性能最好．而且随着靛蓝染色深度的提高织物表面吸附的纤维素酶含量也提高。表面活性剂的存在也影响着酶与织物之间的吸附性能,非离子表面活性剂能促进酶与织物之间的吸附,而阳离子和阴离子表面活性剂则降低了织物表面吸附的酶含量。     

酸性纤维素酶与靛蓝染色织物吸附性能的研究

研究了酸性纤维素酶对靛蓝染色织物的吸附性能,试验表明酶在纤维表面呈多分子层吸附.同时也研究了pH值、靛蓝染色深度和表面活性剂对吸附性能的影响.纤维素酶在pH值为4.88时的吸附性能最好,而且随着靛蓝染色深度的提高织物表面吸附的纤维素酶含量也提高.表面活性剂的存在也影响着酶与织物之间的吸附性能,非离子表面活性剂能促进酶与织物之间的吸附,而阳离子和阴离子表面活性剂则降低了织物表面吸附的酶含量.     

针织牛仔布酶洗中靛蓝返染问题的研究

通过分析针织牛仔布酶洗中靛蓝沾色的平均色差,探讨了温度、时间、纤维素酶浓度以及表面活性剂浓度等因素对靛蓝返染程度的影响。结果表明,织物上吸附的酶蛋白是造成靛蓝返染的主要原因,且沾染程度随纤维素酶浓度增加先升高后降低;非离子表面活性剂TX-10,AEO-9能减轻靛蓝的返染,阴离子表面活性剂十二烷基硫酸钠能降低靛蓝返染,而阳离子表面活性剂则促进了靛蓝的返染程度。     

纤维素酶水解能力的影响因素研究

分析了酸性纤维素酶SHL对纤维素纤维水解能力的各种影响因素,如温度、pH值、织物结构、表面活性剂、染料等。实验结果表明,该酶的最佳处理温度40℃,pH值为5．0。该纤维素酶对纯棉针织物的水解能力远大于对机织物的水解能力：在处理过程中适当提高机械作用力,增加水的硬度以及添加非离子表面活性剂,都能促进酶的水解,而离子型表面活性剂抑制纤维素酶的水解;直接、活性、靛蓝和偶氯染料都抑制纤维素酶的水解．但靛蓝和偶氮染料对纤维素酶的抑制作用较小。     

非离子表面活性剂在生物质发酵生产乙醇中的应用及影响

表面活性剂广泛应用于各个领域,在制备纤维素乙醇过程中添加非离子表面活性剂,研究发现,非离子表面活性剂对木质纤维素原料的预处理和水解过程都产生积极的作用,同时总结了针对不同的木质纤维素原料可以起促进作用的非离子表面活性剂.探讨了非离子表面活性剂在水解过程中对木质纤维素原料结构以及对纤维素酶的影响,着重从纤维素酶的扩散及吸附两个方面阐述了非离子表面活性剂对纤维素酶的影响机制.     

酸性纤维素酶吸附性的影响因素研究

纤维素酶与织物之间的吸附是发生水解反应的先决条件,了解其吸附性能有助于更好地控制水解反应过程。通过对酸性纤维素酶SHL在纯棉针织物表面吸附影响因素的研究发现,吸附量随酶浓度增大线性增大,在pH值4.2￣4.8时有最大吸附量;温度升高吸附量增加;初始吸附速率很大,30 min以后达到饱和吸附;能与棉织物结合的最大酶蛋白分数α=0.4835,半饱和吸附常数K1=0.4948。靛蓝染色织物与纤维素酶的吸附量比未染色织物的吸附量大,织物上的靛蓝与溶液中的靛蓝对纤维素酶存在竞争吸附。     

表面活性剂、染料对纤维素酶活性的影响

测定了非离子、阴离子、阳离子表面活性剂、染料与酶共存体系中的纯绵织物的减量率，比较了共存体系中的酶的相对活性。同时测定色织物的分光反射率曲线，得到光的最大吸收波长。由实验得知：①非离子、阴离子表面活性剂是纤维素酶的激活剂，阳离子表面活性剂是纤维素酶的抑制剂；②直接染料、活性染料是纤维素酶的抑制剂，可能与形成不活泼的染料—纤维素酶复合物有关；③还原染料对纤维素酶无显著的抑制作用     

非离子表面活性剂在旧报纸中性脱墨中的应用

研究了不同非离子表面活性剂之间、非离子与阴离子表面活性剂之间的协同作用,以及不同无机盐、酶制剂对非离子与非离子表面活性剂、非离子与阴离子表面活性剂复配体系脱墨效果的影响。结果表明,非离子表面活性剂(A7)对旧报纸的脱墨和纤维性能的改善有良好效果;两种表面活性剂(A7和A4)协同作用效果更好。在中性条件下,无机盐的加入对脱墨体系也有一定影响;酶制剂的加入对脱墨效果有较大的促进作用。     

AEO类表面活性剂对牛仔布酶洗整理效果的影响

研究了AEO类表面活性剂对牛仔布酶洗整理效果的影响,并通过AEO-9与纤维素酶之间的相互作用,初步分析了其防沾染的作用机理.结果显示:AEO类表面活性剂能够增强纤维素酶对靛蓝牛仔布的酶洗效果,其作用程度受EO链段长度及质量浓度的影响.由紫外光谱及红外光谱谱图分析可知,AEO-9与纤维素酶间会通过氢键结合影响纤维素酶的构象,其中酪氨酸残基受AEO-9作用变化明显,证实了纤维素酶对靛蓝的吸附是引起酶洗返沾色的原因之一.     

表面活性剂与染料对纤维素酶活性的影响

表面活性剂及染料对纤维素酶织物整理效果有影响,产生影响的方向及程度与表面活性剂及染料的离子化程度、离子的价数、分子量的大小及刚性程度有关。部分研究结果显示影响织物整理效果的程度为阳离子表面活性剂〉阴离子表面活性剂〉非离子表面活性剂;活性及直接染料〉还原染料;表面活性剂影响纤维素酶整理效果可能有电荷的作用、络合物的形成、胶束的作用及降低织物表面张力和改善织物表面状态有关;染料对酶的影响机理与表面活性剂有些类似,还可能有竞争性抑制作用和空间障碍作用,但没有表面活性。     

表面活性剂对酶与明胶作用体系的影响

为了正确将表面活性剂使用到制革的酶处理工序中,本试验分别在胰酶和AS1.398酶溶液中添加质量浓度10%的明胶和不同量的十二烷基苯磺酸钠(阴离子型表面活性剂)、十二烷基三甲基氯化铵(阳离子型表面活性剂)和平平加O(非离子型表面活性剂),来测定不同表面活性剂对酶活力和明胶水解程度的影响。试验表明:3种表面活性剂对酶活均起到激活作用;但添加阴离子型表面活性剂后,明胶的水解程度提高。为了探究它们在溶液中所起的主导性作用,在试验第二步,将3种表面活性剂加入到质量浓度0.4%明胶+酶的混合液中,研究混合液在37℃时的Zeta电位的变化。试验表明:加入阴离子型,Zeta电位的绝对值提升;加入阳离子型,Zeta电位从负变为正;加入非离子型,Zeta电位绝对值降低。结合实际制革生产中对皮革高性能的要求,研究表明:在进行酶软化时,应优先选择非离子型表面活性剂。     

表面活性剂对牛仔布酶洗返沾色的影响

研究了不同浓度、种类的表面活性剂对纤维素酶活力以及对牛仔布酶洗效果的影响.结果表明:阴离子型表面活性剂对纤维素酶活力有很大的抑制作用,阳离子次之;非离子型表面活性剂对纤维素酶活力影响不大.脂肪醇聚氧乙烯醚在聚氧乙烯加成数相对较低时,体现较好的防止返沾色的作用;高分子表面活性剂聚乙烯吡咯烷酮(PVP)也具有较好的防止返沾色作用;脂肪醇聚氧乙烯醚类表面活性剂与脂肪胺聚氧乙烯醚类表面活性剂的复配物体现出优异的防止返沾色作用.     

表面活性剂对T1脂肪酶活力的影响

本文研究了非离子型、阳离子型、阴离子型以及两性离子型表面活性剂对T1脂肪酶活力的影响。采用不同浓度的表面活性剂对T1脂肪酶进行处理,再以对硝基苯酚月桂酸酯作为底物,测定处理后的酶活变化。研究发现,低浓度的非离子型表面活性剂对T1都有激活作用,使其相对酶活提高50%到150%。当非离子型表面活性剂的浓度超过其临界胶束浓度,T1的活力受到不同程度的抑制,其中吐温80的抑制作用最为明显。阳离子型(CTAB)、阴离子型(N-L与SDS)和两性离子型(SB3-14)表面活性剂都对脂肪酶的酶活有强烈的抑制作用,可能是因为离子型表面活性剂的带电基团与蛋白质表面的带电氨基酸产生强烈的电荷相斥作用,导致蛋白变性而失去活力。T1脂肪酶是一类具有工业应用价值的耐热脂肪酶,研究不同类型的表面活性剂对其活力的影响,对于在不同目的下选择使用适合的表面活性剂具有重要意义。     

Effects of Tween 60 and Tween 80 on protease activity, thiol group reactivity, protein adsorption, and cellulose degradation by rumen microbial enzymes

Microbial enzymes extracted from mixed ruminal microorganisms were incubated for 2 h with casein and Tween 60 or Tween 80 at 10 concentrations ranging from 0 to 2.0% (vol/vol) to determine the effects of these nonionic surfactants on protease activation and thiol reactivity (unmasking of thiol groups). Rate and extent of protein adsorption to cellulosic substrate (barley straw) was measured in the presence of 0, 0.05, 0.10, 0.25, and 0.50% (vol/vol) Tween 80. Degradation of cellulose by a rumen bacterial fraction was measured over 48 h of incubation with and without Tween 60 or Tween 80 at 0.25% (vol/vol). Maximum accelerations of protease activity achievable with Tween 60 and Tween 80 (calculated from a Michaelis-Menten kinetics model) were 99.2 and 166.8%, respectively. Concentrations of Tween 60 and Tween 80 at which half the maximal velocities were attained were 0.28 and 0.20% (vol/vol), respectively. Tween 80 increased (P < 0.05) the rate and extent of adsorption of microbial protein to barley straw, and the effect was related to concentration of Tween 80 up to 0.10% (vol/vol). Initial rates of cellulose degradation with no surfactant, 0.25% Tween 60, or 0.25% Tween 80 were 0.60, 0.87, and 1.04 micrograms/ml per h, respectively. These nonionic surfactants were effective for enhancing rumen microbial protease and cellulase activities. Thus, further study is warranted to determine their potential for improving ruminant feeding.     

表面活性剂强化的氧脱木素

探讨了各种表面活性剂对竹浆氧脱木素的影响,筛选出对氧脱木素效果较好的表面活性剂;并在此基础上,对效果良好的表面活性剂进行复配,以及复配表面活性剂的ODQP漂白。结果表明:表面活性剂对氧脱木素的促进作用:阴离子表面活性剂非离子表面活性剂阳离子表面活性剂;而阴离子表面活性剂对氧脱木素的促进作用:磺酸盐型磷酸酯盐型硫酸酯盐型羧酸盐型;阴离子表面活性剂中较好的是十二烷基苯磺酸钠、N-油酰基N-甲基牛磺酸钠和直链烷基苯磺酸钠(LAS);非离子表面活性剂中较好的是高碳脂肪醇聚氧乙烯醚(AEO7)、改性异构醇醚JX08-01和醇醚硫酸钠(AES)。结果同时表明:将对氧脱木素较为有效的表面活性剂进行复配,可以更好地改善氧脱木素,最优的复配方式为阴离子表面活性剂-阴离子表面活性剂-非离子表面活性剂。这种复配表面活性剂强化的氧脱木素浆进行DQP漂白,纸浆白度达到84.2%ISO,黏度和白度稳定性也较好,并且在相同的打浆度下,OD_XQP漂白浆的裂断长、撕裂度和耐破指数也比常规ODQP漂白浆明显提高。     

Effects of pH and cationic and nonionic surfactants on the adsorption of pharmaceuticals to a natural aquifer material

A wide range of pharmaceutical compounds have been identified in the environment, and their presence is a topic of growing concern, both for human and ecological health. Adsorption to aquifer materials and sediments is an important factor influencing the fate and transport of pharmaceutical compounds in the environment. Surfactants and other amphiphiles are known to influence the adsorption of many compounds and may be present in the environment from wastewaters or other sources. The work described here examines the adsorption of four pharmaceutical compounds, acetaminophen, carbamazepine, nalidixic acid, and norfloxacin, in the presence of a natural aquifer material. Adsorption was studied as a function of pH and in the presence and absence of two surfactants, cetylpyridinium chloride (CPC), a cationic surfactant, and Tergitol NP9, an ethoxylated nonionic surfactant. In the absence of surfactants, results indicate a 1-2 orders of magnitude variation in adsorption affinity with changing pH for each of the two quinolone pharmaceuticals (nalidixic acid and norfloxacin) but no measurable adsorption for carbamazepine or acetaminophen. In the presence of surfactants, adsorption of acetaminophen and carbamazepine was enhanced to extents consistent with compound hydrophobicity, while adsorption of nalidixic acid and norfloxacin was not. At high pH values, the anionic species of nalidixic acid exhibited enhanced adsorption in the presence of the cationic surfactant, CPC.     

Morphological study of cationic polymer–anionic surfactant complex precipitated in solution during the dilution process

We investigated the phase diagrams and the morphology of the complexes that were formed by cationic polymers, cationic cellulose (CC) and cationic dextran (CD), and by anionic surfactant‐based sodium poly(oxyethylene) lauryl ether sulfate (LES). The anionic charge of the LES‐based surfactants was changed by adding an amphoteric surfactant, lauryl amidopropyl betaine acetate (LPB), or a nonionic surfactant, polyoxyethylene stearyl ether (C18EO25). We discuss the relationship between the complex aggregation process and the morphology of the precipitated complexes. The morphologies of CC complex aggregates, which precipitated during the dilution process in a model shampoo solution, changed from membranous forms to mesh‐like forms by decreasing the charges of both the CC and the surfactant. Their touch on hair in the rinsing process changed from sticky to smooth and velvety, corresponding to their rheological properties. In contrast, CD complex aggregates had a membranous form and a smooth touch independently of the charges on the polymer and surfactant. These results suggested that the control of the charges of both the polymer and surfactant and the choice of polymer structure are important for excellent conditioning effects upon rinsing with shampoo.     

Micellar partitioning and its effects on Henry's law constants of chlorinated solvents in anionic and nonionic surfactant solutions

Micellar partitioning of volatile chlorinated hydrocarbons in surfactant solutions and its effects on vapor-liquid equilibrium is fundamental to the overall design and implementation of surfactant-enhanced aquifer remediation. Surfactant micelles greatly enhance contaminant recovery from the subsurface; however, the reduced volatility of organic compounds compromises the aboveground treatment of surfactant-laden wastewaters using air-stripping process. Batch equilibrium tests were performed to acquire micellar partition coefficients (Km) and apparent Henry's law constants (H*) of three prominent groundwater contaminants (tetrachloroethylene, trichloroethylene, cis-dichlorethylene) in the presence of two anionic surfactants (sodium dodecyl sulfate, SDS; sodium dodecylbenzene sulfonate, SDBS) and two nonionic surfactants (Triton X-100 and Tween 80). The H* values were significantly reduced in the presence of all four surfactants over their critical micelle concentrations (cmc's). On a cmc basis, the anionic surfactant SDS had the greatest effect on H*, followed by SDBS, Triton X-100, and Tween 80. Anionic surfactants decreased H* to an order of magnitude lower than nonionic surfactants, although nonionic surfactants decreased the H* at concentrations significantly lower than the anionic surfactants due to their lower cmc's. Nonionic surfactants present higher Km and molar solubilization ratio than anionic surfactants. Tetrachloroethylene has the highest Km values among three chlorinated solvents, which agrees well with the hydrophobicity (Kow) of these chemicals. An empirical correlation between log Km and log Kow is developed on the basis of data from this study and the Km values reported for a number of chlorinated and nonchlorinated hydrocarbons. Equilibrium data were also tested against three sets of models that describe the partitioning of volatile compounds in vapor-water-micelle phases. Applications of these models in experimentally determining Km from batch vapor-water equilibrium data are discussed.     

Surfactant cleaning of ultrafiltration membranes fouled by whey

A polyethersulphone ultrafiltration membrane was prepared for concentration of whey. The membrane was fouled by whey and the effect of different cleaning agents on flux recovery of the fouled membrane was studied. The optimum cleaning procedure for membrane regeneration was elucidated. The results showed that a combination of surfactants (anionic, cationic and nonionic) may be employed as the optimum cleaning agent for maximum flux recovery. The fluorescence studies revealed that the cationic surfactant interact with proteins by breaking the intra‐chain hydrophobic bonding and providing electrostatic repulsion. Changing the alkyl chain from dodecyl to hexadecyl increases the interaction of surfactant–protein. Dodecyltrimethylammonium bromide (DTAB) provided a weak interaction with whey proteins than to tetradecyltrimethylammonium bromide (TTAB) and cetyltrimethylammonium bromide (CTAB). All data obtained in this study support a surfactant–protein interaction in which hydrophobic forces play a dominant role. The nonionic surfactants poly(oxyethylene) isooctyl phenyl ether (TX‐100) and anionic surfactants SDS interact with amino acids in the inner protein structure thus denaturate tertiary protein structure and reduce hydrophobic interaction of proteins by membrane surface.     

牛仔水洗条件与靛蓝沾色的关系

模拟生产实际情况，收集纯靛蓝牛仔布水洗残液进行靛蓝染料的再沾色试验。通过测定白衬布的R值，定量分析沾色的程度，研究了水洗温度、pH值、纤维素酶种类、表面活性剂以及水洗时间对沾色的影响。结果表明，影响靛蓝再沾色的主要因素是纤维素酶种类、表面活性剂以及水洗时间，而温度、pH值的影响较小。