【摘要】 采用漆酶/TEMPO/O₂体系（TEMPO用量控制在1%,2%,4%和8%）氧化壳寡糖（COS）制备得到改性壳寡糖（MC）,利用电导滴定和低场核磁共振波谱（LF-NMR）分析产物中羧基含量及水的存在形态,并检测了吸湿保湿性和抗氧化性能。结果表明,MC中羧基含量随着TEMPO用量增加而增多,MC-8中羧基含量最高达2.82%;随着羧基含量的增加,MC分子内结合水数量先增加后减小,吸湿保湿能力也呈现相同变化趋势,MC-2在饱和硫酸铵和饱和碳酸钾溶液中60 h的吸湿率最高达63.14%和20.26%,24 h的保湿率为4.71%;羧基含量的增加有利于提高产物的抗氧化性能,MC-8在0.5 g/L质量浓度下ABTS自由基清除率为85.47%。改性壳寡糖的研究在化妆品领域具有潜在的应用价值。更多还原

【Abstract】 Modified chitooligomer（MC） was prepared by oxidation of chitooligomer（COS） using laccase/TEMPO/O₂ system（TEMPO dosage was controlled at 1%, 2%, 4% and 8%）. The carboxyl content and water existing forms in products were analyzed by conductometric titration and low-field nuclear magnetic resonance（LF-NMR）, and the moisture absorption-retention activity and anti-oxidant activity were detected. The results show that the carboxyl content in MC increases with the TEMPO usage, and the carboxyl content in MC-8 is as high as 2.82%. With the increase of carboxyl content, the amount of bound water in MC increases at first and then decreases, and the moisture absorption-retention capacity shows the same trend. The moisture absorption rate of MC-2 in saturated ammonium sulfate and saturated potassium carbonate solution for 60 h is up to 63.14% and 20.26%, respectively. The moisture retention rate for 24 h is 4.71%. The increase of carboxyl content is beneficial to improve the anti-oxidant activity of the product, and the ABTS radical scavenging rate of MC-8 at the mass concentration of 0.5 g/L is 85.47%. The study indicates that MC has potential application value in the field of cosmetics.更多还原