【摘要】 为了寻求安全有效的美白材料,采用漆酶/TEMPO氧化法对壳寡糖（COS）分子结构的C6位进行修饰制备羧基化壳寡糖（C-COS）,并对C-COS进行核磁共振(¹³C NMR)、黑色素抑制效果检测及其对酪氨酸酶的抑制动力学测试。结果表明,核磁共振谱图中,在化学位移为181.46×10^-6处出现了明显的C6位羧基吸收峰,表明漆酶/TEMPO体系成功将壳寡糖C6位氧化并制得C-COS;在一定浓度范围内,C-COS对黑色素的抑制率随羧基含量的增加而增强,当羧基含量为0.6451 mmol/g时,C-COS对黑色素的抑制率达到52.92%;C-COS对酪氨酸酶抑制的动力学研究结果显示它对酪氨酸酶的抑制作用属于可逆抑制中的竞争型抑制。通过探究C-COS对黑色素的抑制效果及机理,为其提供能够作为皮肤美白添加剂的直接依据。更多还原

【Abstract】 The specific C-6 oxidation by laccase/TEMPO of chitooligomer（COS） and carboxylate chitooligomer（C-COS） was studied to obtain a safe and effective skin-whitening material. Nuclear magnetic resonance(¹³C NMR) was used to detect the C-COS structure. Besides, the inhibitory effects on melanin and tyrosinase inhibition kinetics studies of C-COS were also measured. The results showed that a peak appeared at 181.46×10^-6 in the ¹³C NMR spectrum of C-COS, corresponding to ■ carbon bond, which indicated that the C6 hydroxyl groups of COS were successfully oxidized into carboxyl groups by laccase/TEMPO system. The rate of inhibition of C-COS on melanin increased with increasing concentration of the samples within limits. When the content of carboxyl groups was 0.6451 mmol/g, the inhibitory effect of C-COS on melanin reached 52.92%. The kinetics research denoted that C-COS displayed a competitive inhibitory effect to the tyrosinase, which belonged to one of three reversible inhibition types. In this study, the inhibitory effect and mechanism of C-COS on melanin were explored and it would provide support for C-COS as a skin whitening agent in the future.更多还原