林蛙抗菌肽的制备及抑菌活性研究

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p H 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。

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

Objective: In this study , ultrasonic wave-assisted extraction was used to extract the active peptides from the epidermis of rana chensinensis. Methods: With pH4.5 acetic acid-sodium acetate buffer as extraction solvent, ultrasonic wave method was used to extract the frog skin peptide. The amino acid composition and antibacterial activity of the active peptides were analyzed using UPLC, bacteria count and filter method. Results: Under ultrasound conditions, antimicrobial peptides percentage could reach 37.5%. Antimicrobial peptides crude product could effectively inhibit the growth of series microorganisms including Gram-positive bacteria, Gram-negative bacteria and fungus . The bacteriostatic rate could reach 100% when acting 5 min. The predictive best diameter of the inhibitory zone for the antimicrobial peptides was 1812mm. Conclusion: Ultrasound method can use to extract antibacterial peptide from rana chensinensis skin material. The antibacterial peptides was alkaline polypeptide, and it had significant inhibition for both gram-positive bacteria and gram-negative bacteria .