[关键词]
[摘要]
本研究以黄粉虫为试材,采用碱性蛋白酶酶解黄粉虫蛋白制备获得了抗菌肽,并对其进行分离纯化,比较了不同组分及纯化后抗菌肽的抑菌活性、热稳定性及分子量。结果表明:大孔吸附树脂对蛋白酶酶解液动态吸附并梯度洗脱后得到5个组分,抑菌试验表明无水乙醇洗脱组分的抑菌活性最强。采用制备型HPLC对无水乙醇洗脱组分进一步纯化,得到两个组分(H-1,H-2),其中组分H-2对大肠杆菌、沙门氏菌和金黄色葡萄球菌均表现出较强的抑菌活性,且其最小抑菌浓度(MIC)为0.512 mg/mL。热稳定性试验表明,H-2具有较好的热稳定性,121℃加热20 min仍能保持较高活性。液质联用(LC-MS)结果表明,H-2的分子量为756.82Da。本研究为黄粉虫抗菌肽的高效分离和纯化提供了科学依据,为黄粉虫抗菌肽在食品防腐中的应用提供了基础数据。
[Key word]
[Abstract]
Antibacterial peptides were prepared by hydrolysis of the proteins from Tenebrio molitor using alkaline protease. The antibacterial peptides were further separated and purified. Five fractions were obtained from the dynamic adsorption of the protease hydrolysate on macroporous adsorption resin and gradient elution. Theantibacterial activity, thermostability, and molecular weight of different fractions of the peptides were compared. The antimicrobial susceptibility test indicated that the ethanol-eluted fraction exhibited the strongest antimicrobial activity. This fraction was further separated into two subfractions (H-1 and H-2) by preparative high-performance liquid chromatography (HPLC). The H-2 subfraction showed relatively strong antimicrobial activities on E. coli, Salmonella and Staphylococcus aureus, with a minimum inhibitory concentration (MIC) of 0.512 mg/mL. The thermostability tests indicated that H-2 was heat stable and could maintain a relatively strong antimicrobial activity after being heated to 121 ℃ for 20 minutes. The liquid chromatography–mass spectrometry (LC-MS) results indicated the molecular weight of H-2 was 756.82 Da. The results of this study provide a scientific basis for efficient separation and purification of antibacterial peptides from Tenebrio molitor and provide data supporting the application of antibacterial peptides from Tenebrio molitor as food preservatives.
[中图分类号]
[基金项目]
陕西省农业科技攻关项目(2012K02-14)