林蛙抗菌肽的制备及抑菌活性研究

Study on preparation and in vitro antibacteral activity of polypeptide from the epidermis of Rana chensinensis

中文关键词:  林蛙抗菌肽  超声波提取  氨基酸  抑菌

英文关键词:antimicrobial peptides  ultrasonic extraction  amino acid  antimicrobial activity

中文摘要:

      目的 超声波方法提取林蛙表皮多肽, 对其氨基酸组成和抑菌活性进行分析。方法 以pH 4.5醋酸-醋酸钠缓冲液为提取溶剂, 超声波方法提取林蛙表皮多肽, 超高效液相色谱(UPLC)方法分析其氨基酸组成, 同时采用活菌计数和滤纸片方法测定其抑菌活性。结果 超声波方法提取林蛙多肽, 提取率为19.81%, 多肽分子量在3000~5000 Da, 该活性多肽作用2 min对大肠杆菌、金黄色葡萄球菌、白色念珠菌、铜绿假单胞菌抑菌率均可达85%以上, 作用5 min抑菌率可达100%; 其对4株菌抑菌圈直径均可达10 mm以上。结论 采用超声波方法可以从中国林蛙皮中提取抗菌肽物质, 该抗菌肽为碱性多肽, 对革兰氏阳性菌、革兰氏阴性菌均具有很强的抑菌活性。

英文摘要:

      Objective Active peptides from the epidermis of Rana chensinensis were extracted by ultrasonic wave, amino acid and antibacterial activity were researched. Methods With ultrasonic wave and pH 4.5 acetic acid-sodium acetate buffer as extraction solvent, skin peptides from the frog were extracted, the amino acid composition and antibacterial activity of polypeptides were analyzed by ultra performance liquid chroma-tography, colony counting and filtering paper. Results Under ultrasonic wave conditions, extraction rate and molecular weight of polypeptides was 19.81% and 3000~5000 Da. The antimicrobial rate of polypeptides to Escherichia coli, Staphyloccocus aureus, Candida albicans and Pseudomonas aeruginosa were more than 85% when acting 2 min, and 100% when 5 min., the predictive best diameter of the inhibitory zone for the antimicrobial peptides was 1812 mm. Conclusion Ultrasound method can be used to extracted antibacterial peptide from Rana chensinensis skin material. The antibacterial peptides were alkaline polypeptides, and had a better inhibition for both gram-positive bacteria and gram-negative bacteria .