松香基阴离子交换树脂的制备及其对己糖碱性降解色素的吸附作用

蔗糖在生产过程中产生的己糖碱性降解色素（Alkaline degradation products of hexoses,HADPs）会导致成品糖色值增加,从而降低成品糖品质。采用悬浮聚合法制备新型松香基阴离子交换树脂（Rosin-based anionic exchange resin,RAER）,用于除去糖汁HADPs。采用扫描电子显微镜、氮气吸附-脱附比表面积及孔径分布测试仪、同步热分析仪等对RAER进行表征,结果表明树脂孔隙结构丰富且热稳定性好。研究了RAER对HADPs的吸附性能,在树脂投加量为0.05 g/mL,吸附温度为70 ℃,接触时间为10 h,pH值为7及HADPs浓度为100 mg/L,RAER对HADPs的脱色率可达到100%,再生20次后脱色率仍有92.2%,RAER具有良好的重复使用性能。Zeta电位分析表明,RAER吸附HADPs行为存在静电吸引作用（离子交换）。RAER吸附HADPs动力学符合准二级动力学模型（R2≥0.99）,等温线符合Freundlich模型（R2≥0.98）,热力学参数ΔH=62.32 kJ/mol,吸附机理是以化学吸附为主的多层吸热过程。     

互贯型树脂的制备及对木糖母液的脱色性能

设计制备了互贯型脱色树脂PDVB/PMATAM，通过FT-IR、SEM手段探究了树脂的理化性质，采用静态吸附实验考察了PDVB/PMATAM树脂对木糖母液的脱色性能和作用机理。结果表明，制备的PDVB/PMATAM树脂呈现均匀的球形结构，表面为疏松多孔的形态，平均粒径为0.3～0.45 mm,BET比表面积约187.85 m²/g，平均孔径约17.5 nm。PDVB/PMATAM树脂兼具疏水作用、π-π堆积、氢键、离子交换等作用，对木糖母液具有良好的脱色性能，木糖母液的脱色率达到94.5%，对酚类有机物和糠醛的吸附量分别为14.44mg/g和4.41 mg/g，总糖损失率较低。采用Langmuir模型和Freundlich模型对PDVB/PMATAM树脂的吸附等温线数据进行了拟合，拟合结果显示更符合Langmuir模型。此外，PDVB/PMATAM树脂易于再生，复用性能稳定，是一种有良好应用前景的用于糖液脱色精制的吸附剂。     

低聚木糖的脱色工艺

研究了 10种不同的活性炭和 6种阴离子交换树脂对低聚木糖溶液的脱色效果 ,并求得了它们的吸附等温线 .结果表明 ,糖用活性炭AC2 和AC6 及阴离子树脂D30 1 G对低聚木糖溶液具有较好的脱色效果 ,对糖液色素的吸附符合Freundlich方程 .在进一步的扩大试验中 ,采用AC2 、AC6 (10 %AC2 + 3%AC6 ,用量相对于糖液的干固物质 )和阳离子树脂 732、阴离子树脂D30 1 G的组合 ,低聚木糖溶液的总脱色率达到 95 .3% ,总的糖损失为 2 0 % .     

糖熏色素的纯化工艺及稳定性研究

目的:对糖熏色素进行纯化,研究糖熏色素的结构与性质。方法:本文利用大孔吸附树脂对糖熏色素进行纯化,并对纯化后糖熏色素的稳定性进行了研究。结果:XAD-7型大孔吸附树脂对糖熏色素具有较好的吸附和解吸能力。糖熏色素静态吸附与解吸工艺的最佳工艺条件为糖熏色素粗提液浓度60 μg/mL,糖熏色素粗提液pH8.0,吸附温度35 ℃,解吸液浓度40%乙醇,pH10.0,解吸温度40 ℃。其动态吸附与解吸的最佳工艺条件为径高比为1:6,上样流速2.0 mL/min,样液浓度400 μg/mL,解吸液浓度40%乙醇,解吸流速为1.5 mL/min。结论:糖熏色素经XAD-7型树脂静态和动态工艺纯化后,其纯度分别提高45.13%和36.55%,经纯化后的糖熏色素易溶解,溶液澄清且呈现亮黄色,对光敏感但具有较高的热稳定性,初步推测其为Ⅰ类焦糖色素。     

糖用树脂对美拉德色素的吸附性能分析

研究了5种树脂D730、201×7、D202、SD300和D750对美拉德色素溶液的脱色效果,并研究了选定树脂对美拉德色素溶液脱色效果的最佳工艺条件和脱色性能。结果表明:D202树脂对美拉德色素溶液的脱色效果最好;优化的工艺条件是料液比为1∶5(g∶m L),温度60℃,吸附时间6h,此时脱色率为74.4%;D202树脂对美拉德色素溶液的吸附符合Freundlich等温吸附方程。     

低聚木糖分离纯化的研究

利用Freundlich吸附等温方程对活性炭和阴离子交换树脂的色素吸附效能进行了评价,选择活性炭Ly-T-ac和离子交换树脂D-301作为低聚木糖液中色素的吸附剂。通过单因素实验确定了低聚木糖液的活性炭脱色条件为:温度80℃,pH5.0,活性炭用量4%,脱色时间1.5h,活性炭对糖液的脱色率为81.40%。阴离子交换树脂D-301在9%用量,温度40℃脱色2.5h下对糖液的脱色率为40.50%。低聚木糖糖液经过阴阳离子交换树脂脱盐处理后,脱盐率为65.65%。     

银杏果多糖树脂脱色工艺

通过研究6种大孔吸附树脂和2种离子交换树脂对银杏果多糖溶液色素脱除的影响,筛选出3种树脂:大孔阴离子交换树脂脱色1号、D900和非极性的大孔吸附树脂DA-201C。通过正交试验对脱色条件进行优化。在静态吸附试验研究的基础上,筛选出效果较好的树脂进行动态试验研究。结果表明:银杏果多糖中的色素可能以带负电荷的非极性小分子色素为主,在采用脱色1号树脂,pH值为4.5,温度为25℃,上柱速度为1.5mL/min,上样浓度为选择4 mg/mL,柱容量为2BV的条件下,多糖的脱色率为82.37%,多糖保留率为79.12%,蛋白去除率为88.39%。     

大孔吸附树脂脱除枸杞多糖色素技术研究

以宁夏枸杞为原料提取枸杞多糖,采用9种大孔吸附树脂对多糖提取液中色素脱除技术进行研究。在静态实验的基础上,采用正交实验筛选出色素脱除效果最佳的树脂。以脱色率、多糖保留率和蛋白清除率为指标,衡量树脂脱色效果。结果表明:D318树脂脱除色素的效果最佳,样液质量浓度3mg/mL、树脂用量3g/25mL、pH7、处理3h时D318树脂的脱色率、多糖保留率和蛋白清除率分别为67.32%、85.49%和58.76%。     

大孔吸附树脂对荔枝粗多糖的脱色条件研究

研究了9种大孔吸附树脂对荔枝多糖溶液的色素脱除率和多糖保留率的影响,筛选出非极性大孔树脂HPD-100进行后续研究。通过单因素实验和正交实验对脱色条件进行优化,研究发现,采用树脂HPD-100,在温度30℃、时间1.5h、糖液/树脂比为12:1条件下,脱色率可以达到75.54%,多糖保留率可以达到75.43%。荔枝多糖的色素以非极性小分子色素为主。     

大孔吸附树脂对刺梨果汁单宁脱除及其色泽的影响

为有效脱除刺梨果汁中的单宁和色素,提高刺梨果汁品质,选用4 种大孔吸附树脂对刺梨果汁进行脱色和脱单宁处理。结果表明：与其他3 种树脂相比,LX-60大孔吸附树脂的吸附效果最好,当树脂用量为4.0 g时,脱色率为88.18%,单宁脱除率为44.12%,且LX-60树脂的吸附等温线符合Freundlich方程。大孔吸附树脂吸附后刺梨果汁总糖和总酚含量分别显著下降至79.47%和70.18%,可溶性固形物、可滴定酸及VC的保留率分别为81.40%、84.62%和96.48%。在动态吸附实验中,刺梨果汁在大孔吸附树脂上样量为5 倍柱体积、流速为3.3 mL/min的条件下,LX-60大孔树脂对色素类物质和单宁的脱除率分别为71.56%和21.17%,脱除效果较好。因此,LX-60大孔吸附树脂能够有效脱除刺梨果汁中的单宁和色素类物质并改善品质。     

浓香型原酒中塑化剂的吸附剂筛选

选用4种大孔树脂和4种酒类专用活性炭为吸附剂,采用静态吸附法,首先对57%酒精度模拟加标酒样进行吸附实验,以邻苯二甲酸二甲酯(dimethyl phthalate,DMP)、邻苯二甲酸二异丁酯(diisobutyl phthalate,DIBP)、邻苯二甲酸二丁酯(di-n-butyl phthalate,DBP)、邻苯二甲酸二(2-乙基)己酯(diethylhexyl phthalate,DEHP)4种邻苯二甲酸酯类塑化剂的吸附率为指标进行初选。之后用57%酒精度浓香型原酒进行验证,以塑化剂的吸附率和原酒中己酸乙酯、乙酸乙酯、乳酸乙酯、丁酸乙酯4种香气成分的损失率作为指标,筛选出理想的吸附剂。结果表明:1)JT201、JT203酒类专用活性炭对模拟酒样中4种塑化剂的吸附效果较好,平均吸附率为91.01%和87.21%,大孔树脂中非极性的D4006较其他树脂吸附效果好,吸附率达73.67%;极性大孔树脂NKA-Ⅱ和颗粒活性炭的吸附率不足60%,初选JT201、JT203酒类专用活性炭为原酒中塑化剂的吸附剂。2)JT201、JT203酒类专用活性炭吸附后,原酒中DMP、DBP的去除率均达90%以上,JT201对DIBP、DEHP的去除率均达80%以上,JT203对DIBP、DEHP去除率为78%、72%;JT201、JT203吸附处理后原酒中己酸乙酯、乙酸乙酯、乳酸乙酯、丁酸乙酯分别损失7.7%、6.1%、11.9%、11.6%和10.4%、8.6%、33.9%、16.0%,本研究确定JT201酒类专用活性炭为去除浓香型原酒中塑化剂的最佳吸附剂。     

Recovery of acetoin from the aqueous solution by means of a novel hyper-cross-linked resin: Equilibrium and kinetics

Acetoin is a high value-added product widely used in the food industry. Recovery of acetoin from the aqueous solution based on a polymeric adsorbent is an efficient method. Hence, a novel hyper-cross-linked resin was prepared and the adsorption behaviors of acetoin on the resin were investigated systematically. The results showed that the maximum adsorption capacity of acetoin onto the resin decreased with increasing temperature, ranged from 192 to 102 mg/g. Batch kinetic experiments revealed that the adsorption process was rapid and the equilibrium was reached in 30 min. The intraparticle diffusion and macropore diffusion models were used to predict the adsorption process. The simulation results showed that the macropore diffusion was the adsorption-rate controlling step. The obtained diffusivity (0.77 × 10⁻⁸ m²/min at the temperature of 293.15 K) had the same magnitude as the acetoin molecular diffusivity, indicating that the mass transfer into the resin pores was occurred by molecular diffusion.     

Recovery of vanillin from aqueous solutions using macroporous adsorption resins

A simple method for recovery of dissolved vanillin from aqueous solutions by the adsorption–regeneration technique has been developed. Three macroporous adsorption resins with crosslinked-polystyrene framework were NKA-2, S-8 and H103, respectively. Static equilibrium adsorption studies were used for comparing the adsorption capacities of the three resins. The results showed that H103 resin had the best adsorption capacity because of its large and nonpolar surface areas. The effects of pH, temperature and salt concentration on the adsorption capacity of H103 were investigated. The results revealed that the resin had a maximum adsorption capacity, 416 mg/g (vanillin/resin) in acidic condition when the molecule of vanillin is neutral. Furthermore, its adsorption capacity increased with the increase of temperature and salt concentration. The mass transfer zone motion model was used for analyzing the fixed bed adsorption. H103 resin had a shorter mass transfer zone of 24.7 cm and both NKA-2 and S-8 were higher than 30 cm in the experiment conditions. More than 95.6% of adsorbed vanillin can be recovered by use of 3–5 bed volumes of absolute ethanol. The resin can be used repeatedly by simple regeneration and its adsorption capacity was almost unchangeable.     

基于D152树脂吸附蛋白质结合SERS测定鱼肉中的鸟嘌呤含量

基于大孔树脂除杂与表面增强拉曼光谱的灵敏实时性,建立一种鱼肉中鸟嘌呤含量的快速检测方法。以D152树脂为填料,柱内直径1 cm,柱高20 cm,蛋白吸附率在83%～92%之间,鸟嘌呤滤除率大于95%。经单因素试验筛选和正交试验优化得出,上样流速为3 mL/min,洗脱液pH值为4.0以及洗脱流速为0.5 mL/min。基于银包金纳米颗粒（silver-coated gold nanoparticles,Au@Ag NPs）为表面增强基底,鸟嘌呤质量浓度在0.001～100 mg/L范围,鸟嘌呤质量浓度与拉曼强度呈线性关系,R2为0.969 9,检出限为0.1 mg/L。整个检测过程只需10 min,且无需复杂的样品处理。结果表明,D152树脂作为填料的层析柱能有效去除鱼肉中蛋白质等杂质的干扰,以Au@Ag NPs为基底的表面增强拉曼光谱技术的方法能够灵敏、快速的检测鱼肉中痕量嘌呤,检出限低于现有的高效液相色谱法,为开发设计水产品中嘌呤的快速检测方法提供研究基础。     

Evaluation of the adsorption behavior of polyacetylenes onto a food-grade resin for the debittering of carrot juice

In the present study, a procedure for the adsorptive removal of bitter principles, such as the polyacetylenes falcarinol, falcarindiol, and falcarindiol-3-acetate, from carrot juice using a food-grade macroreticular, non-ionic adsorption resin was investigated. To characterize the adsorption behavior of the target compounds, the influence of the independent factors resin amount, stirring rate, pH value, and temperature was studied first in batch-scale experiments. Based on mathematical models obtained from the analysis of the D-optimal design applied, optimal adsorption conditions of each polyacetylene were deduced. Taking together these findings, the adsorption behavior of polyacetylenes was investigated in column experiments. To enhance the binding rates by increasing contact times, the carrot juice was two- and threefold re-applied to the column at 30 °C. As expected, relative amounts of polyacetylenes bound by the adsorbent increased with prolonged contact time of carrot juice and resin material. After a contact time of 64 min, nearly 90% of total polyacetylenes were sorbed onto the resin surface. Therefore, the described adsorption technique may present a valuable tool for the removal of polyacetylenes from carrot juice and thus for debittering. On the other hand, adsorption may be utilized for the recovery and enrichment of these plant secondary metabolites and their use as a functional ingredient in pharmaceutical products and dietary supplements, respectively.     

Size effects on adsorption of hematite nanoparticles on E. coli cells

Adsorption of engineered nanoparticles (NPs) onto bacterial cells is critical for quantifying nanobio interactions as well as toxicokinetic properties of NPs. The purpose of this work was to study adsorption of hematite (α-Fe(2)O(3)) NPs onto Escherichia coli cells and to determine the particle size effects on the adsorption kinetics. Adsorption of large NPs (76 and 98 nm) on cells reached equilibrium faster (within 30-40 min) than small NPs (approximately 60-90 min). The adsorption rates in mg Fe/(L · s) decreased in the order of 98 nm > 76 nm > 53 nm > 26 nm. However, adsorption rates expressed as the number of adsorbed hematite NPs per unit cell surface area in #/(m2 · s) were faster for small NPs than those for large NPs. To interpret the size effects on adsorption kinetics, the Extended Derjaguin-Landau-Verwey-Overbeek (EDLVO) theory was combined with interfacial force boundary layer (IFBL) theory. The computed adsorption rates for different sizes had excellent agreement with the experimental data, and they explained that that faster kinetics for smaller NPs could be attributed to faster particle mobility and lower energy barriers in the total interaction energy. This study lays the groundwork for quantifying the kinetic behavior of NPs interacting with microbial cells, and the results provide insight into adsorption processes at the nanoscale.     

D301阴离子交换树脂对大豆异黄酮分离特性的影响

为更好地将离子交换树脂应用于大豆异黄酮的分离纯化,研究了乙醇含量、pH、温度、初始浓度等条件对D301阴离子交换树脂吸附分离大豆异黄酮的影响。静态吸附实验结果表明,该树脂在以水为溶剂、pH 8左右、40℃时对大豆异黄酮有最好的吸附效果。穿透曲线实验表明,动态饱和吸附量受温度影响较大,当柱温为50℃、初始浓度C07.03 mg/mL时,饱和吸附量为105.0 mg/g干树脂。洗脱曲线实验表明,采用体积分数75%乙醇洗脱,异黄酮回收率为89.3%,产品中大豆异黄酮含量高达56.0%,含量比原料提高了十几倍。表明D301阴离子交换树脂对大豆异黄酮的分离纯化具有较好的选择性和应用前景。     

大孔树脂分离纯化杜仲翅果中桃叶珊瑚甙的研究

为获得较高纯度的桃叶珊瑚甙,采用大孔树脂吸附法对杜仲翅果中桃叶珊瑚甙粗提液进行纯化研究。比较5种大孔吸附树脂对桃叶珊瑚甙的静态吸附-解吸效果,从中筛选出适合桃叶珊瑚甙分离纯化的树脂,并对其动态吸附和解吸性能进行研究。结果表明:D4020树脂最适合桃叶珊瑚甙的纯化;当上样液浓度为3mg/mL、pH7、上样速率2mL/min、上样液体积40mL时,树脂达到动态吸附饱和;再用120mL50%(v/v)乙醇溶液,以2mL/min的流速可以洗脱完全。经过D4020树脂的纯化,桃叶珊瑚甙精制品纯度达到62.54%。     

AB-8大孔树脂对中华补血草根多酚的吸附洗脱特性

从S-8、NKA-9、AB-8、NKA和D4020大孔树脂中筛选出AB-8树脂,研究了AB-8树脂对中华补血草根多酚的吸附洗脱特性。结果表明:AB-8树脂对中华补血草根多酚的饱和吸附时间为5h,吸附等温线符合Lang-muir模型,饱和吸附量为55.30mg/g,提取液pH值对吸附过程影响不显著;以质量浓度1.99mg/mL的提取液上柱,流速为1mL/min时,吸附泄漏点为10BV(柱床体积,1BV=30mL),饱和点为32BV,因此,采用串柱法有利于AB-8树脂吸附能力的发挥;用体积分数70%乙醇作为洗脱剂,以流速1mL/min洗脱,获得的多酚纯度为58.29%。     

吸附树脂对蛹虫草黄酮纯化工艺条件优化

以蛹虫草黄酮粗提物为研究对象,分析黄酮纯化过程中树脂种类、上样体积、淋洗液pH值、洗脱液体积分数与体积及树脂重复使用次数多种影响因素,优化吸附树脂对黄酮的分离纯化工艺。通过对AB-8、D-101、NKA-9和NKA-Ⅱ 4 种吸附树脂对蛹虫草黄酮的静态吸附、静态解吸和静态吸附动力学等特性的研究,发现AB-8吸附树脂对蛹虫草黄酮有较高的吸附速率和单位吸附量,且易于解吸,是蛹虫草黄酮分离的理想树脂。通过优化实验,确定AB-8吸附树脂对蛹虫草黄酮分离纯化的最优工艺条件为树脂装柱体积100 mL时,上样体积40.0 mL、黄酮上样量47.536 mg、淋洗和洗脱速率2 BV/h、淋洗液pH 5、洗脱液乙醇体积分数和洗脱体积分别为85%和500 mL,树脂重复使用次数为2 次,在此条件下,蛹虫草黄酮的回收率在65%以上,纯度在17%以上,具有良好的分离纯化效果。