鱿鱼蛋白抗菌液及其美拉德反应产物制备及抑菌作用研究

Study on the preparation and antibacterial activity of squid protein hydrolysate and Maillard reaction product

中文关键词:  鱿鱼蛋白  酶解  鱿鱼腐败菌  美拉德反应  抑菌作用  膜损伤

英文关键词:squid protein  hydrolysis  specific spoilage organisms of squid  Maillard reaction  antibacterial activity  membrane damage

中文摘要:

      目的 制备抗菌型鱿鱼蛋白水解液, 实现鱿鱼资源的高值化利用。方法 以鱿鱼蛋白(鱿鱼头和加工碎肉)为原料, 经风味蛋白酶、胰蛋白酶、胃蛋白酶、碱性蛋白酶和中性蛋白酶水解, 测定各水解液对鱿鱼腐败菌(specific spoilage organisms of squid after end storage at room temperature, SE-SSOs)的抑菌性, 选择合适蛋白酶水解鱿鱼蛋白, 在最适酶解温度和酶解pH下, 研究加酶量和酶解时间对水解液抑菌活性影响, 制备鱿鱼蛋白抗菌液, 通过美拉德反应提高鱿鱼蛋白抗菌液对SE-SSOs的抑菌活性, 探讨抑菌模式。结果 胃蛋白酶水解鱿鱼蛋白所得水解液对SE-SSOs的抑菌效果强于其他4种蛋白酶, 在胃蛋白酶最适pH 2.0和酶解温度37℃下, 胃蛋白酶添加量500 U/g和酶解2.0 h制备了鱿鱼蛋白抗菌液(squid protein antibacterial hydrolysate, SAH), SAH中分子量6500 Da左右和低于1000 Da肽组分的相对含量达到47%。在SAH中分别添加1%和3%质量体积比葡萄糖、果糖和壳聚糖, 在120℃油浴下加热30 min进行美拉德反应, 其中添加3%果糖的SAH美拉德反应产物(记作SAH-3Fru MRPs)对SE-SSOs抑菌作用强于SAH和其他美拉德产物。扫描电镜结果显示SE-SSOs由杆菌和球菌组成, 经SAH和SAH-3Fru MRPs作用后细胞膜的完整性遭到破坏, 且在SAH-3Fru MRPs作用下菌体膜损伤情况更为严重, 可见部分菌体已被完全裂解。结论 胃蛋白酶水解法适用于制备抗菌型鱿鱼蛋白水解液, 通过美拉德反应能进一步提高水解液的抑菌作用, SAH和SAH-3Fru MRPs均可以通过膜损伤方式抑制SE-SSOs中特定菌。因此, SAH及SAH-3Fru MRPs有进一步开发应用前景。

英文摘要:

      Objective To prepare antibacterial hydrolysate of squid protein and utilize squid proteins in high value. Methods Squid protein, including squid head and processed meat, used as the raw materials was hydrolyzed by flavor protease, trypsin, pepsin, alkaline protease and neutral protease, respectively. The antibacterial activities of these hydrolysates were evaluated by determination of their inhibition activities against the specific spoilage organisms of squid after end storage at room temperature (SE-SSOs). An appropriated protease was selected for the preparation of squid protein antibacterial hydrolysates. Under the optimum pH and enzymatic temperature, the effects of enzyme addition amount and hydrolysis time on the antibacterial activity of the hydrolysate were determined. Furthermore, the antibacterial activity of squid protein hydrolysate was increased through Maillard reaction, as well as the antibacterial action mode was explored. Results The inhibition activity of pepsin hydrolysate against SE-SSOs was stronger than the other four protein hydrolysates. Squid protein antibacterial hydrolysate (SAH) was prepared by addition of 500 U/g of pepsin and hydrolysis for 2.0 hours at the optimal pH of 2.0 and hydrolysis temperature of 37℃. The relative content of peptide fractions with molecular weight of around 6500 Da and <1000 Da in SAH reached 47%. SAH was reacted with 1% or 3% glucose, fructose or chitosan under 120℃ in oil bath for 30 min to prepare the Maillard reaction products. Among which, the Maillard reaction products of SAH with 3% fructose (denoted as SAH-3Fru MRPs) demonstrated stronger antibacterial activity than SAH and the other Maillard reaction products on the inhibition of SE-SSOs. The scanning electron microscopy results showed that SE-SSOs were composed of Bacteria and Cocci. After the action of SAH or SAH-3Fru MRPs, the integrity of the cell membrane of SE-SSOs was disrupted. In addition, compared to SAH treatment, the cell membrane damage of SE-SSOs was more severe under SAH-3Fru MRPs treatment and some cells were observed to be completely lysed. Conclusion The enzymatic hydrolysis method is suitable for the preparation of antibacterial squid protein hydrolysate, and its antibacterial activity can be improved by the Maillard reaction. Both SAH and SAH-3Fru MRPs can inhibit specific bacteria in SE-SSOs through membrane damage mode. Therefore, SAH and SAH-3Fru MRPs can have further prospect development and application.