摘要
目的分析人初乳中溶菌酶(Lysozyme,LYZ)的理化特性及其抗菌活性。方法取产后3d内的产妇乳汁,根据人LYZ标准曲线,求得其中的LYZ活性。将人初乳分别置于60、72、85和100℃水浴中孵育0、1、3、5、10、15、20和30min后取样,检测其中LYZ的活性,分析其热稳定性;将经稀释的人初乳分别调pH值至2.0、4.0、5.0、7.4、9.0和10.0,37℃孵育30min,检测其中LYZ的活性,分析其对pH值的敏感性;将不同的金属离子加入人初乳中,使其终浓度为10mmol/L,测定不同金属离子对人初乳中LYZ活性的影响;采用平板扩散法检测人初乳中LYZ的抑菌谱,并挑选敏感菌株进行定量抑菌试验。结果人初乳中LYZ的活性为(9650±236)U/ml,在60℃～85℃和pH2.0～10.0的条件下均可保持较强的活性,对多种金属离子具有一定的耐受性。人初乳中LYZ对多种革兰阳性及阴性细菌具有不同程度的抑菌作用,但对白色念珠菌无抑制作用。结论人初乳中的LYZ稳定性强,抗菌谱广,具有广泛的应用价值。
Objective To analyze the physico-chemical characteristics and antimicrobial activity of lysozyme（LYZ）in human colostrum.Methods The colostrum was collected from the lying-in women within 3 d after parturition and determined for LYZ activity according to the standard curve.The colostrum was incubated in 60,72,85 and 100℃ water bath respectively,from which samples were taken at various time points（0,1,3,5,10,15,20 and 30 min）and determined for LYZ activity to analyze the thermal stability.The colostrum was diluted,of which the pH values were adjusted to 2.0,4.0,5.0,7.4,9.0 and 10.0 respectively,and incubated at 37℃ for 30 min,then determined for LYZ activity to analyze the sensitivity to pH value.Various metal ions were added into the colostrum,each to a final concentration of 10 mmol/L,to evaluate the effect on LYZ activity.The bacteriocial spectrum of LYZ in human colostrum was determined by plate diffusion test,and the sensitive strains were selected for quantitative bacteriostasis test.Results The LYZ activity in human colostrum was（9 650 ± 236）U/ml,which was stable at 60 ～ 85℃ and pH 2.0 ～ 10.0 and showed a certain resistance to various metal ions.The LYZ in human colostrum showed inhibitory effects at different degrees on various Gram-positive and negative bacteria,while showed no inhibitory effect on Candida albicans.Conclusions The LYZ in human colostrum,with a broad bacteriocial spectrum,showed high stability,which might be applied widely.
出处
《中国生物制品学杂志》
CAS
CSCD
2010年第12期1312-1314,1319,共4页
Chinese Journal of Biologicals
基金
江苏省自然科学基金资助项目(BK2009193
BK2009-615)
江苏省高校自然科学基金资助项目(07KJD310244)
扬州大学科技创新培育基金项目(2008CXJ049
20-07CXJ031)
关键词
人溶菌酶
初乳
理化特性
抗菌活性
Human lysozyme
Colostrum
Physico-chemical characteristics
Antibacterial activity
