Studies On The Separation,Purification And Property Of Chondroitin Sulfate From Tilapia Byproduct

Chondroitin sulfate is a kind of bioactive acid mucopolysaccharide, it has been widely used in treatment of neuralgia, coronary heart disease, keratitis, arthritis and other diseases, but with the research in recent years, chondroitin sulfate has been gradually extended to the field of food and cosmetics. The chondroitin sulfate was extracted from tilapia byproduct (head, fins, tail) by ultrasonic, microwave and ultrasonic-microwave synergistic, respectively. And high-purity chondroitin sulfate was made by ethanol precipitation method after the extract was purified by ultrafiltration. Finally, molecular weight, purity, structure of the sample was analyzed by the Gel Permeation Chromatography (GPC), Ultraviolet Spectrometer (UV), Infrared Spectrometer (IR), High Performance Liquid Chromatograph (HPLC) and Nuclear Magnetic Resonance (NMR), and antioxidant capacity of CS was also determined. Besides, content and structure of CS were preliminary studied in three different parts of the byproduct. The main results were as follows:1. In the three extraction methods, the single factor experiments and response surface analysis were used to optimize the extraction process, which showed that the main factors affected the extraction rate of CS were power, ratio of solid to liquid, extraction time and alkali concentration; and variance analysis showed the power and solid-liquid ratio were the most significant factors.2. In the three extraction methods, extraction rate of chondroitin sulfate was2.513%by ultrasonic-microwave synergistic extraction, which was1.54times of microwave, and4times of ultrasonic-assisted independently.3. The optimum decolorization process was as follows:pH3.5, decolorized20min under70℃, in which decolorization effect is most obviously by pH value and powder activated carbon. And the optimum conditions of purified by ultrafiltration purification were:the temperature of solution was under30℃,2bar for40minutes.4. Chondroitin sulfate sample almost had no nucleic acids and proteins which purity was98.78%; molecular weight of CS was129582and most of composition was chondroitin-C after analyzed by GPC and infrared spectrometer.5. Compared the antioxidant capacity of crude CS and purifed CS with different concentration, the results showed that chondroitin sulfate had a scavenging effect on hydroxyl radical, DPPH· radical and Superoxide anion radical, and the scavenging effect increased as the increasing of CS’s content. 6. Results indicated that the head, fin and tail of tilapia all contain a certain amount of chondroitin sulfate and the chondroitin sulfate content of the head was significantly higher than fin and tail, which was1.69times of the fin,1.78times of the tail. The infrared spectra exhibited that chondroitin sulfate in the three parts were all linked with sulfate groups.