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医用壳聚糖敷料研究进展 总被引:1,自引:0,他引:1
介绍了壳聚糖的生物学特性以及在伤口愈合中的作用。阐述了改进壳聚糖性能的化学、物理方法以及多种形状医用壳聚糖敷料、载药类壳聚糖敷料和医用壳聚糖衍生物敷料的研究进展。 相似文献
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Biodegradable blend films from rice starch–chitosan were developed by casting film-solution on leveled trays. The influence of the ratio of starch and chitosan (2:1, 1.5:1, 1:1, and 0.5:1) on the mechanical properties, water barrier properties, and miscibility of biodegradable blend films was investigated. The biodegradable blend film from rice starch–chitosan showed an increase in tensile strength (TS), water vapor permeability (WVP), lighter color and yellowness and a decreasing elongation at the break (E), and film solubility (FS) after incorporation of chitosan. The introduction of chitosan increased the crystalline peak structure of starch film; however, too high chitosan concentration yielded phase separation between starch and chitosan. The amino group band of the chitosan molecule in the FTIR spectrum shifted from 1541.15 cm−1 in the chitosan film to 1621.96 cm−1 in the biodegradable blend films. These results pointed out that there was a molecular miscibility between these two components. The properties of rice starch–chitosan biodegradable blend film and selected biopolymer and synthetic polymer films were compared; the results demonstrated that rice starch–chitosan biodegradable blend film had mechanical properties similar to the other chitosan films. However, the water vapor permeability of rice starch–chitosan biodegradable blend film was characterized by relatively lower water vapor permeability than chitosan films but higher than polyolefin. 相似文献
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壳聚糖澄清猕猴桃果汁对果汁成分影响的研究 总被引:5,自引:1,他引:4
首先采用离子交换色谱分离壳聚糖k,得到三个壳聚糖组分(壳聚糖a、b、c)。再对未经离子交换色谱分离的壳聚糖k和经离子交换色谱分离所得的三个组分壳聚糖a、b、c澄清猕猴桃果汁前后猕猴桃果汁中化学成分变化和澄清后猕猴桃果汁的透光率、色泽的研究。可以得出,1:未经离子交换色谱分离的壳聚糖k和经离子交换色谱分离所得的三个组分壳聚糖a、b、c都可以有效的澄清猕猴桃压榨果汁,透光率达到94.6%以上;2:壳聚糖k和壳聚糖a、b、c对澄清后猕猴桃清汁的色泽有不同的影响,壳聚糖k澄清后的猕猴桃清汁色泽浅,壳聚糖c澄清后的猕猴桃清汁色泽较深;3:壳聚糖k和壳聚糖a、b、c澄清猕猴桃压榨果汁前后果汁中的可溶性固形物和VC含量相同,不影响猕猴桃果汁的营养价值;4:壳聚糖k和壳聚糖a、b、c澄清猕猴桃压榨果汁前后猕猴桃果汁中总糖、还原糖、蛋白质、总酚含量都有所变化,但是不同壳聚糖对果汁中成分的影响是不同的。 相似文献
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采用高速剪切技术对壳聚糖的机械降解过程进行了研究。考察了剪切时间、转速、温度、壳聚糖原溶液浓度、分子量和溶液pH等因素对壳聚糖降解效果的影响。以壳聚糖的动力黏度下降率来反映壳聚糖的降解程度,分别采用傅立叶变换红外光谱及凝胶渗透色谱对壳聚糖降解前后的结构和分子量分布进行了分析。研究结果表明,纯机械作用能够促进壳聚糖的降解,当壳聚糖原溶液浓度为3 g/L,分子量为100×104,pH为4.6,温度为40 ℃,降解时间为40 min,转速为20000 r/min时,降解效果最明显,动力黏度下降率为20.27%。研究还发现黏度对壳聚糖的机械降解过程有一定影响,当壳聚糖原溶液黏度为4.0 mPa·s时,壳聚糖的黏度下降率最大。本文为深入探究壳聚糖降解机理提供了理论依据。 相似文献
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Sayas-Barberá E Quesada J Sánchez-Zapata E Viuda-Martos M Fernández-López F Pérez-Alvarez JA Sendra E 《Meat science》2011,88(4):740-749
Chitosan of high and low molecular weights was added at 0%, 0.25%, 0.5% and 1% concentrations to a burger model system. Burgers were evaluated by physicochemical analysis, cooking characteristic and storage stability. The antioxidant activity of chitosan was studied in vitro. The addition of chitosan influenced pH and color properties, in molecular weight and concentration dependent ways. Cooking properties were significantly affected by the chitosan. High molecular weight chitosan improved all cooking characteristics compared with control samples. Low molecular weight chitosan increased the shelf life of burgers, enhanced the red color and reduced total viable counts, compared with control and high molecular weight chitosan samples. The antioxidant activity of chitosan was dependent on molecular weight and concentration. The results indicate that high molecular weight chitosan (HMWC) improves all cooking characteristics and antioxidant activity while low molecular weight chitosan extends the red color and reduces total viable counts. 相似文献
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Antimicrobial activity of native chitosan,degraded chitosan,and O-carboxymethylated chitosan 总被引:3,自引:0,他引:3
The antimicrobial activity of native chitosan was compared to that of lipase-degraded chitosan. The effects of O-carboxymethylated (O-CM) substitution on native (molecular weight, 120; degree of deacetylation, 84.71%) and lipase-degraded chitosans were also investigated. The antimicrobial activity of native chitosan was more extensive than that of lipase-degraded chitosan; however, lipase-degraded chitosan was still highly effective and more water-soluble. O-CM chitosan derived from degraded chitosan was more effective than O-CM chitosan derived from native chitosan. O-CM substitution enhanced lipase-degraded chitosan's antimicrobial activity without reducing its solubility. 相似文献
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壳聚糖对金黄色葡萄球菌抑菌活性的研究 总被引:2,自引:0,他引:2
研究了壳聚糖对金黄色葡萄球菌抑菌活性,考察了不同壳聚糖浓度、pH值、金属离子、醋酸浓度对壳聚糖抑制金黄色葡萄球菌活性的影响,并以壳聚糖浓度、pH值、醋酸浓度为因素进行正交试验,确定了壳聚糖对金黄色葡萄球菌抑菌活性的最优条件。实验结果表明,壳聚糖对金黄色葡萄球菌的抑制能力随其浓度的升高而增强;壳聚糖溶于浓度为2%的醋酸溶液时,培养基pH控制在6.0时壳聚糖的抑菌活性最强;金属离子在一定程度上降低了壳聚糖的抑菌活性;这3个因素对壳聚糖的抑菌活性的影响程度为壳聚糖浓度pH值醋酸浓度。 相似文献
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壳聚糖固定化酶研究进展 总被引:2,自引:0,他引:2
介绍壳聚糖作为固定化酶载体的3种主要情况:壳聚糖直接作为固定化酶载体;壳聚糖衍生物作为固定化酶载体;壳聚糖与其他物质共同作为固定化酶载体。壳聚糖及其衍生物的固定化酶具有酶活性高、回收率高和耐贮藏等特点。指出壳聚糖及其衍生物在固定化酶技术领域有着广阔的应用前景。 相似文献
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本文简单介绍了壳聚糖纤维的国内外发展历程;重点阐述了纯壳聚糖纤维,工业化绿色纺丝过程中的关键技术的研究与突破;详细说明了纯壳聚糖纤维在医疗、卫生、纺织、航天、军工、烟草等领域的应用;并提出今后加强产学研合作,加快对纯壳聚糖纤维在高端领域产品的研发,以更好地发挥纯壳聚糖纤维在促进人体健康、提升生活质量方面的作用,推进纯壳聚糖纤维行业持续、健康、快速发展。 相似文献