酶解法制备鲽鱼骨蛋白胨及其细菌培养试验

目的]研究鲽鱼骨蛋白胨的制备工艺并对其在细菌培养中的应用进行了初步探讨。方法]采用乙酸和胃蛋白酶提取鲽鱼骨蛋白胨,以蛋白提取率为指标,在单因素试验基础上,采用正交试验优化制备工艺,并对鲽鱼骨蛋白胨作为氮源在细菌培养中的应用进行了研究。结果]鲽鱼骨蛋白胨提取的最佳工艺条件为:提取时间20 h、提取温度40℃、料液比1∶50 g/m L、胃蛋白酶加酶量3 000 U/g,在此条件下鲽鱼骨蛋白胨的提取率为55.62%。蛋白胨产品的氨基酸种类齐全。通过细菌培养试验发现,对于大肠杆菌、金黄色葡萄球菌和枯草芽孢杆菌,鲽鱼骨蛋白胨的培养效果与市售细菌学蛋白胨相似。结论]鲽鱼骨蛋白胨能够提供细菌生长所需要的氮源营养,可作为氮源应用于细菌的培养。

Preparation of Peptone from Flatfish Bone Using Pepsin and Bacterial Culture Experiment

Objective] To optimize technique for extracting peptone from flatfish bone, and discuss its bacterial culture effect.Method] Pepsin and acetic acid were used to extract peptone from flatfish Limanda aspera.With extraction yield as index, the optimal conditions were determined based on single factor experiment.The bacterial culture effect of peptone as nitrogen source was also studied. Result] The opti-mal processing condition was:extraction time 20 hours, extraction temperature 40 ℃, solid to liquid ratio 1∶50 g/mL and 3 000 U/g pepsin, and the yield of peptone reached up to 55.62%.The amino acid composition of flatfish bone peptone was various and rich.Using three com-mon and typical bacteria Staphylococcus aureus, Escherichia coli, Bacillus subtilis, the performances of flatfish bone peptone was compared to commercial peptone.Results showed that bacterial culture effect of flatfish bone peptone was similar to commercial peptone. Conclusion] The study demonstrates that flatfish bone peptone could provide nitrogen nutrients needed for bacterial growth, and could be used as nitrogen source in the cultivation of the bacteria.