Physicochemical Properties and Structural Characterization of Lignin from Camellia oleifera Shell

In order to make full use of the resources of Camellia oleifera shell,this research using Camellia oleifera shell as raw material,the lignin was extracted from Camellia oleifera shell by acetic acid method and alkaline method,respectively. The basic components,physicochemical properties and structural characterization of acetic acid lignin and alkaline lignin were analyzed. The results showed that acetic acid lignin had a lower purity(91.87%)and higher purity of alkaline lignin(93.37%),and the content ofCand fixed carbon in acetic acid lignin was higher. Antioxidant activity investigation showed that the DPPH radical scavenging index of the extracted acetic acid lignin and alkaline lignin was higher than that of crude dietary fiber. Compared with alkaline lignin,the water holding capacity and swelling capacity of acetic acid lignin were increased by 59.49% and 55.36%,respectively. The binding capacity of saturated fat and unsaturated fat were increased by 5.06% and 2.24%,respectively. The DPPH radical scavenging activity was increased by 10.50%. And the moisture absorption was decreased by 28.14%.Meanwhile,the UV-visible spectra(UV)and infrared spectra(IR)analyses showed that the acetic acid lignin and alkaline lignin are mainly composed of guaiacyl and syringyl,and the guaiacyl content in acetic acid lignin was higher,while the syringyl content in alkaline lignin was higher. Thermogravimetric analysis showed that the thermal stability of acetic acid lignin was higher than that of alkaline lignin,and was more suitable for the preparation of high temperature and heat resistant materials.