Study On The Extraction And Properties Of The Pigment From Sugarcane Juicealcohol Wastewater

With the development of human society, people pay more and more attention to their health. The importance of antioxidant capacity of natural products which has obvious advantages has been recognized for health care. This study aims directly on the extraction and properties of the pigments from sugarcane juice alcohol wastewater which exhibit antioxidant activity. The results will provide theoretical and technical basis for the extraction of the pigments and application in the future.Ion exchange fiber of GX-Pigment and D-101 macroporous resin were used for the recovery of the pigment by static adsorption and desorption. Mixture of 15mL 2.32% NaOH and 7.5% NaCl was used as the eluent of 3g ion exchange fiber in order to get the pigment A and 10mL 60% ethanol was applied as eluent of 1g macroporous resin to harvest the pigment B. The recovery rate of pigment A and B was 87.94% and 73.45% under the above conditions.Studies on the stability of the pigment showed that hydrogen peroxide, vitamin C, UV light and potassium sorbate could decolor pigment A with different degrees. And hydrogen peroxide and vitamin C showed the strongest decoloring ability. Hydrogen peroxide could also make the color of pigment B fade seriously. Pigment B was more sensitive than A to pH. Antioxidant activity of the extracted pigment had been studied by using different kinds of method. When the concentration of the pigment A was 10 mg/mL, reducing ability and the scavenging ability of the pigment A in hydroxyl radical system and 1,1-diphenyl-2-picrylhydrazyl(DPPH·) system were 34.58%, 59.27% and 92.31% of those of 1mg/mL tea polyphenols(control group), respectively. While for the pigment B with concentration of 1.0 mg/mL, reducing ability and the DPPH·scavenging ability were 16.78% and 78.51% of those of control group, respectively. And the scavenging ability of pigment B with concentration of 10 mg/mL in hydroxyl radical system was 92.53% of that of the control group.The DPPH? scavenging ability of the pigment A increased in some extent with the addition of Fe3+,Al3+,Cu2+. The addition of sodium nitrite made the DPPH ? scavenging ability of pigment A and pigment B increase by 15.89% and 73.56% respectively .The ultraviolet light also enhanced the scavenging ability of the pigment A. The DPPH? scavenging activity of the pigment A and B was 95% when 0.2g/L VC was added. Compared to the original pigment B, the DPPH? scavenging activity increased by 2.34 times when 0.5mmol/L Al3+ was added. The addition of NaNO2,Zn2+ and Cu2+ made the DPPH? scavenging activity of pigment B increase by 31.82%,73.56% and 9.57% respectively.The molecule weight of main components of the pigment A varied from 3000 to 5000 Da. However, components with lower molecular weight played an important role in pigment B. When the pigment A and B was dissolved in water with pH7.0, negative charge of -28.703 and -3.906, were detected separately. The content of flavonoids of the pigment A and B were 10.4 mg and 41.7 mg Rutin equivalent per gram pigment respectively. And the content of polyphenols of the pigment A and B were 11.24 mg and 40.0 mg Gallic acid equivalent per gram pigment separately.