Antibacterial activity and mechanism of monolauroyl-galactosylglycerol against Bacillus cereus

The antibacterial activity and mechanism of monolauroyl-galactosylglycerol (MLGG) against Bacillus cereus were investigated. The minimum inhibitory concentration of MLGG against B. cereus was 0.156 mg/ml. The inhibition growth curve assay also revealed that MLGG presented good antibacterial activity against B. cereus. Alkaline phosphatase activity assay, nucleotide leakage and cell viability analysis demonstrated that MLGG disrupted the integrity of cell wall and cell membrane of B. cereus. Scanning electron microscopy and transmission electron microscopy results showed obvious morphological and ultrastructural changes of B. cereus membrane, further confirming the damage of cell membrane integrity caused by MLGG. In summary, MLGG might exerted its antibacterial activity mainly by an action mode of membrane disruption, and it was expected to be an alternative for the development of new food preservatives. (C) 2017 Elsevier Ltd. All rights reserved.