罗非鱼骨胶原蛋白质的提取及其性质

Extraction and Characterization of Collagen from Tilapia Bone

为充分利用鱼片加工废弃物鱼骨中的胶原蛋白质,采用单因素以及正交实验法,研究胃蛋白酶在酸性介质条件下提取罗非鱼骨胶原蛋白质的最佳工艺,精制后的胶原蛋白质采用SDSPAGE电泳、紫外及傅立叶变换红外扫描,圆二色检测,氨基酸分析,热变性温度测定等方法 ,分析胶原蛋白质的理化性质。结果显示:乳酸溶液p H 2.6,温度30℃,料液比1∶30(g/mL),加酶量200U/g,提取时间24h,此工艺条件下的粗胶原蛋白质提取率达到70.28%,得率为12.76%;罗非鱼骨胶原蛋白质含有2条α链和1条β链,属于典型的I型胶原蛋白质;罗非鱼骨胶原蛋白质的主要氨基酸为甘氨酸、脯氨酸、羟脯氨酸、谷氨酸和丙氨酸;罗非鱼骨胶原蛋白质的热变性温度为34.5℃。研究表明,采用胃蛋白酶提取鱼骨胶原蛋白质,提取率和纯度均较高。

Fish bone,containing plenty of collagen,is the main offal from fish fillet processing.The collagen from Tilapia bone after removing impurities was extracted by pepsin digestion in acid medium condition.The effects of extraction medium,temperature,material to liquid ratio,pepsin addition,extraction duration on yield of collagen were investigated.The optimum conditions using lactic acid as medium to extract collagen were pH 2.6,material to liquid ratio（w/v） 1∶30,30 ℃,200U/g pepsin addition,extraction time 24h,and the yield of extracted collagen reached 70.28%（12.76% when compared with the initial weight of Tilapia bone）.Then,the extracted crude collagen was further purified and its physicochemical property was determined by the methods of SDS-PAGE,UV and FT-IR scanning,DSC,CD and amino acid analysis.The results indicated that the extracted Tilapia bone collagen belongs to typical collagen Ⅰ with two α and one β chains.Furthermore,the Tilapia bone collagen contains high percentages of Gly,Pro,Hyp,Glu and Ala and its denaturation temperature was 34.5 ℃.In conclusion,the extracted Tilapia bone collagen by pepsin digestion has a higher yield and purity.