Development of anti-bacterial material included in cyclodextrin with environmentally controlled release characteristics

本课题研究了根据环境温度和湿度的不同，制备环糊精包合抗菌材料的技术。1）将一氯三嗪基-β-环糊精（MCT-β-CD）共价键合到纤维素粉末和和纸上。MCT-β-CD的键合量与水含量、反应温度和MCT-β-CD浓度有关。该反应表现为MCT-β-CD在纤维素材料上的物理吸附，随后出现零级化学反应; 2）固定化环糊精能够包合并释放扁柏酚作为模型抗菌香料。MCT-β-CD对扁柏酚的平均包合摩尔比为0.85，与扁柏酚在天然β-环糊精中的包合分数基本相同。3）在50℃下，不同相对湿度条件下，测定了固定化MCT-β-CD中扁柏酚的释放速率。释放动力学可以使用Avrami方程建模。与未结合的MCT-β-CD相比，固定化MCT-β-CD中包含的扁柏酚可以很好地控制释放。4）为了研究含有扁柏酚的和纸的抗菌能力，将其暴露于实验室空气，然后将积累的活微生物转移到标准生长琼脂中。含有扁柏酚的平板显示根本没有微生物生长。功能性和纸具有良好的抗菌性能。

In this research and development, we have studied the technique to make anti-bacterial material included in cyclodextrin in accordance with the environmental temperature and humidity.1)Monochlorotriazinyl-β-cyclodextrin (MCT-β-CD) was covalently bonded to cellulose powder and washi paper. The amount of MCT-β-CD bonded to them was dependent on the water content, the reaction temperature and the concentration of MCT-β-CD of the solution. The reaction was characterized as a physical adsorption of the MCT-β-CD on the cellulose materials, followed by an appearing zero order chemical reaction.2)The immobilized cyclodextrin was able to include and release hinokitiol as a model antibacterial flavor. The average molar inclusion ratio to MCT-β-CD was 0.85, which is nearly the same inclusion fraction as for hinokitiol in native β-cyclodextrin.3)The release rates of hinokitiol included in the fixed MCT-β-CD were monitored at different relative humidities at 50℃ The release rates were markedly increased with the increase in the relative humidity. The release kinetic could be modeled using the Avrami equation. The hinokitiol included in the immobilized MCT-β-CD could be well controlled to release compared to that in the unbound MCT-β-CD.4)To investigate the antibacterial ability of the hinokitiol containing washi paper, it was exposed to laboratory air, followed by a transfer of the accumulated vital microorganism to standard growth agar. The plate containing hinokitiol showed no microbial growth at all. The functional washi exhibited a good antibacterial ability.