卡拉胶寡糖活性的研究进展

与卡拉胶相比,卡拉胶寡糖由于其分子量较小、易于吸收等特点,表现出较优的生物活性,越来越被人们所重视。主要介绍了近年来卡拉胶寡糖活性的研究进展。     

角叉菜化学成分及其生物活性的研究进展

角叉菜作为一种常见的大型海藻,不仅含有丰富的化学成分,提取物具有较强的生物活性,还是提取卡拉胶的重要藻类之一。对近年来国内外学者对角叉菜的化学成分、提取物的生物活性及其应用研究情况进行了综述。     

透明质酸等化妆品用生物活性多糖吸湿保湿性能测定

目的：研究单一生物活性多糖及复配物的吸湿保湿性能。方法：通过干燥器控制湿度的方法对透明质酸、鲨鱼软骨素、海藻酸钠、水溶性壳聚糖、卡拉胶寡糖等天然保湿材料与常用保湿剂甘油进行吸湿和保瀑性能测试。结果：在RH81％条件下,各试样吸湿能力顺序为：卡拉胶寡糖,甘油,海藻酸钠,水溶性壳聚糖,透明质酸〉鲨鱼软骨素;在RH43％条件下,各试样吸湿能力顺序为：甘油,海藻酸钠,水溶性壳聚糖,透明质酸,卡拉胶寡糖,鲨鱼软骨素。硅胶环境下,各试样的保湿能力顺序为：透明质酸〉水溶性壳聚糖〉卡拉胶寡糖〉鲨鱼软骨素〉海藻酸钠〉甘油。遥过对5种聚糖的两两复配实验,筛选出卡拉胶寡糖、水溶性壳聚糖、透明质酸3种生物活性多糖与其它多糖复配效果较好。结论：本实验所采用的吸湿、保湿性能评价方法准确、简单、可靠,适用于各种类型的保湿剂,可作为一种化妆品用保瀑剂的性能评价方法。     

涂料涂装技术快讯

福建农林大学利用生物活性大分子研制环保涂料福建农林大学采用魔芋葡甘聚糖、卡拉胶、大豆分离蛋白、蔗糖酯、天然色素和水为主要原料,研发了一种环保涂料。该新产品的生产工艺包括载体制备、微胶囊制备和环保涂料制备。由     

卡拉胶的性能及某些新应用

结合卡拉胶的凝胶保水性、与蛋白质相互作用、增稠助悬性,介绍了国内外卡拉胶在食品领域及医学领域的某些新应用。     

卡拉胶在食品中的应用

卡拉胶是一种天然亲水植物胶，可用作胶凝剂、悬浮剂等，是前景良好的食品添加剂。本文主要介绍了卡拉胶的性质、应用及市场前景等。     

卡拉胶寡糖的制备及其生物活性的研究

对卡拉胶的降解条件、降解获得的卡拉胶寡糖的理化性质及其抗肿瘤活性进行了研究。结果表明,60℃下用0.5%硫酸降解1%的卡拉胶,可以得到比较均匀、分子量大小不等的多种卡拉胶寡糖。用这种方法获得的卡拉胶寡糖对结肠癌细胞DLD1生长的抑制作用远远强于相同浓度的卡拉胶,为拓宽卡拉胶的应用提供了实验依据。     

卡拉胶在牙膏中的应用

本文介绍了新型粘合剂卡拉胶的特性及应用。     

K-卡拉胶提取过程中碱处理时间对添加K-卡拉胶的鱼糜性质影响

K-卡拉胶是鱼糜制品中常用的添加剂,其性质与卡拉胶硫酸基团和3,6内醚半乳糖含量密切相关。碱处理是K-卡拉胶提取工艺的必要工艺环节,会影响K-卡拉胶的硫酸基团和3,6内醚半乳糖含量。目的:以白鲢鱼糜为原料,研究不同碱处理时间提取的K-卡拉胶对鱼糜白度、持水性、凝胶强度和质构的影响。方法:控制不同的碱处理时间,提取得到不同的K-卡拉胶样品,添加到鱼糜制品中,分析测定鱼糜白度、持水性、凝胶强度和TPA的变化。结果:K-卡拉胶提取过程中碱处理时间对添加K-卡拉胶的鱼糜品质具有显著影响。随着K-卡拉胶提取过程中碱处理时间的增加,添加卡拉胶后鱼糜白度和持水性呈下降趋势,鱼糜硬度、胶着性和咀嚼性呈现上升趋势,但鱼糜破断力、凝胶强度、弹性、内聚性和回复性没有显著性影响。结论:阐明了K-卡拉胶提取过程中碱处理时间对添加K-卡拉胶鱼糜质量的影响,为开发鱼糜制品专用的K-卡拉胶产品提供了技术参考。     

卡拉胶的提取工艺及其在医药领域的应用研究进展

卡拉胶是一种高分子量的线性硫酸盐海洋多糖，由于独特的生物和理化性质赋予了它在各个领域具有广阔的应用潜力。本文综述了近年来卡拉胶的提取工艺技术以及卡拉胶在抗病毒活性、抗肿瘤活性、硒化卡拉胶、对罕见疾病的治疗、载药性能等方面的应用研究进展，并对卡拉胶的研究方向和前景进行了展望。     

Enzymatic and ionic crosslinked gelatin/K‐carrageenan IPN hydrogels as potential biomaterials

Hydrogels of a natural origin have attracted considerable attention in the field of tissue engineering due to their resemblance to ECM, defined degradability and compatibility with biological systems. In this study, we introduced carrageenan into a gelatin network, creating IPN hydrogels through biological methods of enzymatic and ionic crosslinking. Their gelation processes were monitored and confirmed by rheology analysis. The combination of biochemical and physical crosslinking processes enables the formation of biohydrogels with tunable mechanical properties, swelling ratios and degradation behaviors while maintaining the biocompatibilities of natural materials. The mechanical strength increased with an increase in carrageenan content while swelling ratio and degradability decreased correspondingly. In addition, the IPN hydrogels were shown to support adhesion and proliferation of L929 cell line. All the results highlighted the use of biological crosslinked gelatin‐carrageenan IPN hydrogels in the context of tissue engineering. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 10.1002/app.40975.     

Carrageenan: A Food‐Grade and Biocompatible Support for Immobilisation Techniques

Immobilisation of both enzymes and whole‐cell systems is of major importance in the improvement of the stability, activity and reusability of these biocatalysts. This review describes the use of the naturally occurring polysaccharide carrageenan as a support for the immobilisation of biocatalysts. Carrageenan is a food‐grade and biocompatible support material extracted from red seaweeds. Before focusing on the use of carrageenan as an immobilisation support, an overview is given of the present uses of biocatalysts in industrial processes. The basic concepts of enzyme and whole‐cell immobilisation are discussed, as well as the background of carrageenan as a biopolymer. Several examples of enzymes and whole‐cell systems immobilised in carrageenan are discussed. A list of the most relevant patents in this field is presented as well as a list of enzymes and cell systems immobilised in carrageenan as described in the literature.     

Comparative studies on physico-chemical characterization of yeast cells entrapped with alginate and hybrid beads

Natural polymers used as carrier materials in immobilization technology have the advantage of being non-toxic, biocompatible and biodegradable. In the present investigation, immobilization of yeast cells using different polymers has been carried out and the properties such as morphological, hardening, thermal stability and characterization of functional groups of alginate and hybrid beads (alginate–carrageenan and alginate–xanthan gum) have been studied by different techniques such as scanning electron microscope, texture analyzer, differential scanning calorimetry, and Fourier transfer infrared spectroscopy. The swelling behavior in terms of pH variation as well as flow properties of alginate and hybrid beads has also been examined. The hybrid beads prepared from alginate and carrageenan were found to be the best in terms of strength, cell holding capacity, pH and thermal stability. The reusability of beads was also studied in terms of enzyme activity of the entrapped yeast cells. The beads prepared by alginate–carrageenan were found to be more stable than alginate and alginate–xanthan beads. The yeast cells entrapped in alginate–carrageenan beads showed no significant decrease in enzyme activity up to seven batches. Thus, alginate–carrageenan beads can be used as a polymeric carrier/support to develop a stable and long-term immobilized cell system, which indicates its high potential for commercial applications in food and pharmaceutical sector.     

Preparation and potential in vivo anti‐influenza virus activity of low molecular‐weight κ‐carrageenans and their derivatives

Degradation of native κ‐carrageenan was performed using acid hydrolysis aided with microwave heating. Combined with nonofiltration membrane (cut‐off molecular weight 250 Da) separation, 1. 400 Da ‐ 50 kDa low‐molecular‐weight (LMW) κ‐carrageenans were obtained. Narrow molecular weight distribution of LMW κ‐carrageenans could be prepared under pH 2.18 during the microwave power range investigated. The in vivo anti‐influenza virus (IV) activity of three kinds of LMW κ‐carrageenans (3, 5, and 10 kDa), their acetylated derivatives (acetylation degree of 1.5), as well as an acetylated and sulfated derivative of 3 kDa carrageenan (acetylation degree of 1.0 and sulfation degree of 2.4), were investigated using FM1‐induced pulmonary oedema model. These LMW κ‐carrageenans showed significant inhibition against FM1‐induced pulmonary oedema as compared with the virus control, although their activities were inferior to that of positive control, Rabivirin. Introduction of acetyl groups greatly increased their anti‐IV activity. The acetylated 3‐kDa κ‐carrageenan exhibited comparative activity with Rabivirin at both doses of 6 and 30 2. mg/kg·d, and the acetylated and sulfated derivative of 3 kDa carrageenan displayed higher activity than Rabivirin at the dose of 30 mg/kg·d. These results disclosed that 3 kDa κ‐carrageenan with proper acetylation degree and sulfation degree was a potential candidate against influenza virus. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

微波处理对卡拉胶结构性质的影响

探讨微波处理条件对卡拉胶的3，6-脱水-半乳糖(3，6-AG)含量、凝胶强度、融点、凝固点和失重率的影响。结果表明，经不同输出功率微波辐照后卡拉胶的36-脱水-半乳糖含量、凝胶强度、融点、凝固点均呈下降趋势。用SPSS统计软件分析微波输出功率对卡拉胶3，6-AG含量和凝胶强度的影响，结果表明，微波输出功率对卡拉胶的这两个参数均有显著影响。经二元变量相关分析结果表明，微波处理时间与上述几项指标之间，除了失重率之外，均有高度相关性。     

pH-response of chitosan, κ-carrageenan, carboxymethyl cellulose sodium salt complex hydrogels

We synthesized the polyelectrolyte complex hydrogel consisting of chitosan, κ-carrageenan, and carboxymethyl cellulose sodium salt (NaCMC) and investigated the swelling properties of the gel varying with carrageenan/NaCMC compositions. In a lower composition of carrageenan, heterogeneous gels were obtained indicating strong electrostatic interactions among these polyelectrolytes. Oppositely, in a higher composition of carrageenan, a gelation did not occur. It was cleared that a homogeneity of the gel strongly depended on the carrageenan/NaCMC composition. The degree of swelling at the equilibrium decreased proportional to the carrageenan composition. The gels showed a maximum degree of swelling in the range of pH 11-12. The maximum degree of swelling discontinuously decreased with increasing the NaCMC composition and was independent of the composition at a higher composition of NaCMC. Swelling properties in pure water and in alkaline solutions were also affected by salt concentrations of each polyelectrolyte aqueous solutions.     

Chitin whiskers reinforced carrageenan films as low adhesion cell substrates

Carrageenan was used to prepare carrageenan films reinforced with chitin nanowhiskers. Atomic force microscopy was used to characterize the morphology and roughness of the films. Structural characterization was performed using X-ray diffraction and Fourier transform infrared spectroscopy. The mechanical properties were assessed by tensile tests. The prepared nanocomposites were used as cell substrate in order to explore their potential biological applications. HeLa cells were seeded on the samples in order to assess their biocompatibility. The preliminary results show good cell proliferation but low cell adhesion, demonstrating a potential application of this novel material as substrate for tumor cell culture.     

Novel carrageenan-based hydrogel nanocomposites containing laponite RD and their application to remove cationic dye

Novel hydrogel nanocomposites were synthesized by solution polymerization of acrylamide in the presence of carrageenan biopolymer and laponite RD clay. Laponite was used as an inorganic cross-linker. Ammonium persulfate was applied as an initiator. The structure and morphology of the nanocomposites were investigated using XRD, scanning electron microscopy, and transition electron microscopy techniques. The influence of both laponite nanoclay and the carrageenan content on the swelling degree of nanocomposites was studied and it was found that all nanocomposites containing carrageenan component have a high swelling degree compared to a nanocomposite without carrageenan. The obtained nanocomposites were examined to remove a cationic crystal violet (CV) dye from water. The effect of carrageenan and clay contents on the speed of dye adsorption revealed that while the rate of dye adsorption is enhanced by increasing the clay content, it was depressed as the carrageenan content increased in nanocomposite composition. The results showed that the pseudo-second-order adsorption kinetic was predominant in adsorption of CV onto nanocomposites. The experimental equilibrated adsorption capacity of nanocomposites was analyzed using Freundlich and Langmuir isotherm models. The results indicated that the experimental data fit the Langmuir isotherm best. Maximum adsorption capacity was obtained for carrageenan-free nanocomposite with 79.8?mg?g^?1 of adsorbed CV onto nanocomposite.     

Evaluation of mechanical and thermal properties of carrageenan/hydroxypropyl methyl cellulose hard capsule

The inherent source of gelatin used for commercial hard capsules causes a surging demand for vegetarian capsules. In this work, carrageenan is utilized in preparing hard capsules to meet consumer preferences. Hydroxypropyl methylcellulose (HPMC) was incorporated as a reinforcing agent to improve the low mechanical properties of hard capsules made of carrageenan. The HPMC concentration was manipulated from 0.2 to 1.0 w/v% in the carrageenan matrix. The increasing concentration of HPMC exerts significant effects on the tensile strength and elongation at break, with an improvement of 59.1% and 46.9%, respectively, at the optimized HPMC concentration of 0.8 w/v%. The loop strength of the capsule is also increased by 56.4% with decreasing moisture content. The downfield movement from around 3.20 ppm of the carrageenan proton to 3.33 ppm in the proton nuclear magnetic resonanance ( ¹H-NMR) spectrum suggests the formation of intermolecular hydrogen bonding between carrageenan and HPMC, which correlates to the results of Fourier-transform infrared spectroscopy (FTIR) and zeta potential. The glass transition temperature of the film was increased from 37.8 to 65.3°C, showing an upgrade in thermal stability. The film possesses a major mass loss with an activation energy of 64.7 kJ/mol with an increment of 43.4% compared to the control carrageenan. These findings support the conclusion that HPMC enhanced the mechanical properties and thermal stability of the carrageenan film, and the comprehensive analysis of the molecular interaction and decomposition kinetics subsequently may expand the application fields of the carrageenan-HPMC hard capsule as an alternative to gelatin in the future.     

Rheological Characterization of Synergistic Mixtures of Carrageenan and Locust Bean Gum for Aqueous Gelcasting of Alumina

Previous works have shown that carrageenan can be successfully used in the aqueous gelforming of powders, because carrageenan forms a firm gel, similar to that formed by agarose, but at a much lower cost. In this work, the synergistic effect of carrageenan with locust bean gum is studied. The rheological behavior of 2 wt% solutions of these polysaccharides and their mixtures are measured under mixing conditions (60°C) and by recording the viscosity and elastic modulus on cooling. The effect of the addition of these solutions to 50 vol% alumina slurries up to a concentration of 0.5 wt% is studied. Although gelling time increases, the resulting gels are stronger than for carrageenan alone. Gelcast alumina bodies with green and sintered densities of 57% and 97.6% of theoretical have been obtained.