Modulation effect of core-wall ratio on the stability and antibacterial activity of cinnamaldehyde liposomes

Cinnamaldehyde is an active component of some plant essential oils, which has broad antibacterial activity. However, the strong volatility and instability of cinnamaldehyde limits its application. Cinnamaldehyde was encapsulated by liposomes, and the effects of core-wall ratio on the stability and antibacterial activity during storage were investigated. The particle size during storage showed that cinnamaldehyde liposomes with high core-wall ratios aggregated more easily, and the retention ratio of it can maintained at around 60%. The increase of cinnamaldehyde loading could reduce the fluidity of the liposome membrane. The antibacterial activity of cinnamaldehyde liposomes against Staphylococcus aureus during storage was investigated by fluorescence labeling and the killing log value. It was found that liposome-encapsulated cinnamaldehyde might still inhibit bacteria by destroying cell membrane integrity after storage and the persistence was more efficient than that of pure cinnamaldehyde. Therefore, liposomes could improve the stability and long-term antibacterial activity of cinnamaldehyde.