乳铁蛋白和乳铁素的抗菌活性比较

Antibacterial Activities of Lactoferrin Compared with LactoferricinB's

牛乳铁蛋白是从牛乳中提取出来的一种铁结合性糖蛋白,牛乳铁素是从牛乳铁蛋白N-端水解下来的25个氨基酸残基。它们具有多种生物学功能,其中的广谱抗菌性尤为引人注目。本实验以牛初乳中提取的乳铁蛋白及其水解产物乳铁素为研究对象,选取大肠杆菌为实验菌株,进行铁饱和乳铁蛋白和缺铁性乳铁蛋白、乳铁素对大肠杆菌生长抑制的比较研究。研究结果表明:铁饱和乳铁蛋白、缺铁性乳铁蛋白和乳铁素的最小抑菌浓度分别为6mg/ml、3mg/ml和15μg/ml,乳铁素的最小杀菌浓度为30μg/ml。乳铁蛋白水解后,经纯化获得的乳铁素,其抗菌能力较缺铁性乳铁蛋白增加200倍,较铁饱和乳铁蛋白增加400倍。

Lactoferrin （LF） is an iron-binding glycoprotein in milk. Bovine lactoferricin （LfcinB） is a peptide having 25 amino acid residue derived from the N-terminal part of BLf. BLf and LfcinB possess a variety biological functions, and it＇s broadspectrum antibacterial activity is knockout. In this experiment, the antibacterial activity of holo-Lf, apo-Lf and LfcinB was studied and compared, and Escherichia coli was used for studying the antimicrobial growth. The results shown that the minimum inhibitory concentration （MIC） of bovine holo-lactoferrin （holo-LFB）, bovine apo-lactoferrin （apo-LFB） and lactoferricin （LfcinB） against E.coli is 6mg/ml, 3mg/ml and 15 μg/ml and the minimum bactericidal concentration （MBC） of Lfcin against E. coli is 30μg/ml, respectively. The ability of inhibiting E.coli growth enhanced 200 times for apo-LFB and 400 times for holoLFB after LFB was hydrolysised and puritied.