从林蛙皮肤中提取的小分子多肽具有诸多生物活性.以鲜活林蛙为试验材料,剥离皮肤,采用酶解法提取小分子活性多肽,并研究其理化性质.结果表明:制备的林蛙皮多肽的紫外特征吸收峰位于220 nm处,280 nm附近吸收峰较小;分子量主要分布在190～1 000 u,并且在250～540 u的分布最多,占37.47％;该混合多肽具有多种生物活性因子,尤其是抗菌肽和凋亡调控蛋白;在不同pH值缓冲溶液中都具有良好的溶解性;抑菌试验表明其对大肠杆菌和金黄色葡萄球菌有不同程度的抑菌活性.证明制各的小分子混合多肽有望成为新的制剂原料.“,”There are many biological activities in small molecular polypeptides which were extracted from the skin of Rana chensinensis,and to study the physicochemical properties of the polypeptides will provide a theoretical basis for polypeptides preparation.In this study,live Rana chensinensis was used as experimental material,skin was peeled,small molecular polypeptides were extracted by enz ymolysis method and their chemical and physical properties were studied.The study showed that characteristic ultraviolet absorption peak of the frog skin polypeptides appeared at 220 nm,while absorption peak near 280 nm was small;molecular weight distribution was between 190～1 000 u,and content between 250～ 540 u was 37.47％,which is the largest proportion.Polypeptides from Rana skin had a plurality of bioactive factors,and in particular they contained antimicrobial peptides and apoptosis regulating proteins;peptides showed good solubility in different pH buffer solutions;bacteriostatic test showed that peptides had different degrees of antibacterial activity on E.coli and Staphylococcus aureus.The above results show that the small molecule polypeptides prepared in our study are expected to be new preparation materials.