【作者】 谢果凰；

【导师】 杨文鸽；

【作者基本信息】 宁波大学 ， 食品科学， 2010， 硕士

【摘要】 硫酸软骨素是广泛存在于动物结缔组织中的糖胺聚糖,具有缓解关节炎、降血脂、抗氧化、抗血管生成等多种生理功能,广泛应用于食品、医药、化妆品等领域,具有广阔的开发前景。“海中霸王”鲨鱼广泛分布于印度洋、太平洋和大西洋,为全球性鱼类,但鱼翅加工的下脚料鲨鱼软骨并未得到充分利用。有研究表明鲨鱼软骨富含硫酸软骨素,虽然有厂家开始生产鲨鱼硫酸软骨素,但目前尚存在提取工艺复杂、费时、成本高、产品质量不稳定、得率低等问题。因此,优化鲨鱼硫酸软骨素提取工艺、提高产品得率和纯度,提高鲨鱼产业的附加值,迫在眉睫。本研究以鲨鱼软骨为原料,对鲨鱼硫酸软骨素进行分离、提纯和降解,并对其性质和抗氧化功能进行研究。主要包括:1、优化鲨鱼硫酸软骨素的提取工艺。采用稀碱-酶解法分离提取鲨鱼硫酸软骨素,运用单因素试验和响应面分析对鲨鱼硫酸软骨素的碱液提取工艺进行了优化。结果表明:碱提温度对硫酸软骨素的提取率影响显著,其次为碱液浓度。确定最佳提取工艺条件为:碱液浓度4%、碱提温度35℃、碱提时间3h,该工艺条件下分离提取得鲨鱼硫酸软骨素粗品,提取率为14.50%,纯度为86.01%。2、纯化并分析鉴定鲨鱼硫酸软骨素。粗品经Q-Sepharose FF离子交换色谱柱分离纯化得鲨鱼硫酸软骨素纯品,并用紫外光谱、红外光谱和核磁共振等对其进行产品分析。Q-Sepharose FF离子交换色谱柱分离纯化效果好,峰形窄而对称,结构单一,收率为91%,制品纯度达99.82%、相对分子量为44771、各项指标符合标准、不含蛋白和核酸,结构分析为6-硫酸软骨素。3、鲨鱼硫酸软骨素及其降解产物的抗氧化测定。采用H2O2+抗坏血酸法氧化降解硫酸软骨素,得到不同分子量范围的硫酸软骨素样品。比较了鲨鱼硫酸软骨素纯化前后、降解前后抗氧化能力的变化。结果表明:鲨鱼硫酸软骨素呈现良好的抗氧化活性;硫酸软骨素粗品中的杂质对其抗氧化能力有影响,与纯品相比,鲨鱼硫酸软骨素粗品清除DPPH·、OH·的能力有所提高,而还原Fe3+的能力却有所下降;鲨鱼硫酸软骨素随着分子量的减少,其抗氧化性增加。更多还原

【Abstract】 Chondroitin sulfate (ChS), a kind of acid glycosaminoglycan with ease arthritis, hypolipidemic, anti-oxidation and anti-angiogenesis functions, is extensively present in the connective tissue of animals and used in food, medicine, cosmetics and other areas, and has broad development prospects.“Sea King”---Shark is the universal fish, which is widely distributed in the Indian Ocean, Pacific and Atlantic Ocean, but the byproduct of shark cartilage from shark fin processing has not been fully utilized. Some studies has shown that shark cartilage is rich in chondroitin sulfate, although many manufacturers has began to produce shark chondroitin sulfate, but the complex extraction process, time-consuming, high-cost, unstable product quality and low yield problems also remain. Therefore, it’s urgent to optimize extraction process of shark chondroitin sulfate to improve product yield and purity, in order to improve the added value of shark industry. In this study, chondroitin sulfate was isolated and purified from shark cartilage, and its properties and anti-oxidation function were studied. The research contents include following aspects:1. The extracting process of chondroitin sulfate from shark cartilage was optimized.ChS was extracted from shark cartilage with dilute alkali-enzymatic solution. Single-factor experiments and response surface analysis were used to optimize the alkali extraction process. The factor of alkali extraction temperature on the yeild of ChS was significant, followed by alkali concentration. The optimal conditions of alkali extraction were as follows: alkali concentration 4%, extraction temperature 35℃, extraction time 3h. Under this optimal conditions, the extraction rate and purity of ChS were up to 14.50% and 86.01%, respectively.2. The chondroitin sulfate from shark cartilage was purified, analyzed and identified.Crude ChS from shark cartilage were purified by Q-Sepharose FF ion-exchange column, then analyzed by UV spectra, IR spectroscopy and nuclear magnetic resonance.The results showed that Q-Sepharose FF ion-exchange column could effectivly purify the crude ChS from shark cartilage. After purified by ion-exchange column, ChS had no protein and nucleic acid left and its purity was shown to be on a single elution peak. The yeild, purity and molecular weight of ChS were up to 91%, 99.82% and 44771, respectively. Moreover, the product was confirmed mainly to be 6-ChS by structural analysis of IR and NMR.3.The antioxidant function of shark chondroitin sulfate and its degraded products were determined.ChS from shark cartilage were degraded by the reaction system of ascorbate and hydrogen peroxide. Compared the antioxidant capacity of crude ChS, purified ChS and degraded ChS with different molecular weight, the results showed that ChS has good anti-oxidation activity. Impurities in the crude ChS affected their antioxidant capacity, and the scavenging ability of crude ChS on DPPH·,OH·were better than the purified ChS , but the reducing power on Fe3+ is just opposite. Moreover, the antioxidant capacity of degraded ChS were relevant to their molecular weight, lower the molecular weight of degraded ChS, better the antioxidant capacity.更多还原