单宁酸改性鱼皮明胶-透明质酸复合微球的制备及性质研究

文章以大黄鱼鱼皮中提取的鱼皮明胶（fish skin gelatin，FSG）为主体材料，通过乳液模板法制备鱼皮明胶-透明质酸（fish skin gelatin-hyaluronic acid，FSG-HA）复合微球，再利用单宁酸（tannic acid，TA）对复合微球混合交联，构建具有高抗氧化及抗菌活性的单宁酸改性鱼皮明胶-透明质酸（FSG-HA/TA）复合微球。采用动态光散射仪、透射电子显微镜（transmission electron microscope，TEM）、激光扫描共聚焦显微镜（confocal laser scanning microscope，CLSM）、傅里叶变换红外光谱仪（Fourier transform infrared spectrometer，FTIR）和紫外-可见分光光度计等表征FSG-HA和FSG-HA/TA的微观形貌和结构，测定其抗氧化及抗菌活性。结果表明：FSG-HA和FSG-HA/TA均表现出球形结构，单宁酸的交联改性降低了FSG-HA的粒径分布，增强了鱼皮明胶与透明质酸之间的氢键作用，使微球结构更紧密且均匀；FSG-HA和FSG-HA/TA对DPPH自由基和ABTS阳离子自由基的清除率具有质量浓度依赖性，清除率最高分别达93.75%和67.63%。此外，改性后FSG-HA/TA对金黄色葡萄球菌和大肠杆菌的抑制效果显著，尤其是对金黄色葡萄球菌的最高抑菌率达95%。因此，FSG-HA/TA具有较强的抗氧化和抗菌性能，作为食品保鲜和生物医药领域的功能性材料具有巨大的应用潜力。

Fish skin gelatin (FSG) extracted from Pseudosciaena crocea skin was used as the main material. Fish skin gelatin-hyaluronic acid (FSG-HA) composite microspheres were prepared by the emulsion template method. Tannic acid (TA) was used to cross-link the microspheres to construct TA-modified fish skin gelatin-hyaluronic acid (FSG-HA/TA) composite microspheres with high antioxidant and antibacterial activities. Dynamic light scattering, transmission electron microscope (TEM), confocal laser scanning microscope (CLSM), Fourier transform infrared spectrometer (FTIR) and ultraviolet-visible absorption spectroscopy were used to characterize the microscopic morphology and structure of FSG-HA and FSG-HA/TA, and their antioxidant and antibacterial activities were determined. mined. The results indicated that both FSG-HA and FSG-HA/TA exhibited spherical structures. The cross-linking modification of TA reduced the particle size distribution of FSG-HA microspheres, enhanced the hydrogen bonding between FSG and HA, and made the microsphere structure more compact and uniform. The scavenging rates of FSG-HA and FSG-HA/TA against DPPH radicals and ABTS cationic radicals were concentration-dependent, with the scavenging rates reaching up to 93.75% and 67.63%, respectively. In addition, the modified FSG-HA/TA had significant inhibitory effects on Staphylococcus aureus and Escherichia coli, with the inhibition rate against Staphylococcus aureus reaching up to 95%. In summary, FSG-HA/TA composite microspheres have strong antioxidant and antibacterial properties and exhibit significant potential as functional materials in the fields of food preservation and biomedicine.