Wang Wenyue, Wang Rui, Zhang Guiju, Chen Fangli, Xu Baocai
School of Food and Chemical Engineering, Beijing Key Laboratory of Flavor Chemistry, Beijing Higher Institution Engineering Research Center of Food Additives and Ingredients, Beijing Technology and Business University, Beijing 100048, People's Republic of China (ORCID: https://orcid.org/0000-0001-8712-5532 [G.Z.]).
China Rural Technology Development Center, Beijing 100045, People's Republic of China.
J Food Prot. 2020 Feb 1;83(2):331-337. doi: 10.4315/0362-028X.JFP-19-259.
Naturally occurring monoglyceride esters of fatty acids have been associated with a broad spectrum of antimicrobial activities. We used an automated turbidimetric method to measure the MIC and assess the antimicrobial activity of five monoglycerides (monocaprin, monolaurin, monomyristin, monopalmitin, and monostearin) against pathogenic strains of Staphylococcus aureus, Bacillus subtilis, Pseudomonas aeruginosa, and Escherichia coli. The antibacterial activity of monocaprin was highest because its carbon chain is shorter than those of other monoglycerides. The MICs of monocaprin against S. aureus, B. subtilis, P. aeruginosa, and E. coli were 0.32, 0.32, 2.5, and 2.5 mg/mL, respectively. Monocaprin had antibacterial activity under neutral and alkaline conditions (pH 7.0 to 9.0) but had no inhibitory effect on S. aureus, B. subtilis, and E. coli under weakly acidic conditions (pH 6.0). The antibacterial mechanism of monocaprin against gram-positive strains (S. aureus and B. subtilis) resulted from destruction of the cell membrane. In contrast, the antibacterial activity of monocaprin against gram-negative strains (P. aeruginosa and E. coli) was attributed to damage to lipopolysaccharides in the cell walls. Because of its inhibitory effect on both gram-positive and gram-negative bacteria, monocaprin could be used as an antibacterial additive in the food industry.
天然存在的脂肪酸单甘油酯具有广泛的抗菌活性。我们使用自动比浊法测定了五种单甘油酯（单癸酸甘油酯、单月桂酸甘油酯、单肉豆蔻酸甘油酯、单棕榈酸甘油酯和单硬脂酸甘油酯）对金黄色葡萄球菌、枯草芽孢杆菌、铜绿假单胞菌和大肠杆菌等致病菌株的最低抑菌浓度（MIC）并评估了其抗菌活性。单癸酸甘油酯的抗菌活性最高，因为其碳链比其他单甘油酯的碳链短。单癸酸甘油酯对金黄色葡萄球菌、枯草芽孢杆菌、铜绿假单胞菌和大肠杆菌的MIC分别为0.32、0.32、2.5和2.5mg/mL。单癸酸甘油酯在中性和碱性条件（pH 7.0至9.0）下具有抗菌活性，但在弱酸性条件（pH 6.0）下对金黄色葡萄球菌、枯草芽孢杆菌和大肠杆菌没有抑制作用。单癸酸甘油酯对革兰氏阳性菌株（金黄色葡萄球菌和枯草芽孢杆菌）的抗菌机制是由于细胞膜被破坏。相比之下，单癸酸甘油酯对革兰氏阴性菌株（铜绿假单胞菌和大肠杆菌）的抗菌活性归因于细胞壁中脂多糖的损伤。由于其对革兰氏阳性菌和革兰氏阴性菌均有抑制作用，单癸酸甘油酯可作为食品工业中的抗菌添加剂。
