山西老陈醋类黑精的分离及其抑菌活性

Separation of Melanoidin from Shanxi Aged Vinegar and Its Antibacterial Activity

为探究老陈醋类黑精的抑菌作用,采用超滤和尺寸排阻色谱法将山西老陈醋冻干粉（Shanxi aged vinegar extract,SAVE）分离成不同分子质量的水提物和类黑精部分,采用Na Cl解离法将醋类黑精解离为类黑精骨架和小分子复合物两部分,用比浊法测定各组分对大肠杆菌、金黄色葡萄球菌和枯草芽孢杆菌的抑菌活性。结果表明：SAVE中的类黑精具有显著的抑菌活力（P〈0.05）,类黑精对SAVE的抑菌性发挥了主要作用;类黑精中分子质量在3~5 k D的组分抑菌活力最强,其对3种受试菌的最低抑菌浓度（minimal inhibitory concentration,MIC）均为5 mg/m L;类黑精组成中的小分子复合物比类黑精骨架部分具有更强的抑菌活性。

Shanxi aged vinegar extract（SAVE, lyophilized aqueous extract） was separated by ultrafiltration into different molecular weight aqueous soluble fractions and the high molecular weight fraction was further purified into melanoidins. Thereafter, the melanoidins were dissociated in aqueous Na Cl solution into two components： skeleton and small molecular weight complex. The antibacterial activity of these components against E. coli, Staphylococcus aureus and Bacillus subtiliswas determined by a turbidimetric method. Results indicated that melanoidins from SAVE had a significant antibacterial activity（P 0.05）, and they played a major role in the bacteriostatic activity of SAVE. The antimicrobial activity of the melanoidin component with molecular weight of 3-5 k D was the strongest, with minimal inhibitory concentration（MIC） of 5 mg/m L for all three bacteria tested. The small molecular weight complex from melanoidin had greater bacteriostastic activity than the skeleton part.