e-Polylysine-coated liposomes loaded with a 8-CD inclusion complex loaded with carvacrol: Preparation, characterization, and antibacterial activities

In this study, carvacrol (Car) is first embedded in 8-cyclodextrin (8-CD) by the freeze-drying method to form the 8-cyclodextrin-Carvacrol inclusion compound (8-CD-Car), and then 8-CD-Car liposomes (8-CD-Car-Lip) and 8-CDCar liposomes coated with e-polylysine (e-PL/8-CD-Car-Lip) with different concentrations (0-20 mg/mL) of 8-CDCar were prepared. The liposomes were characterized, and their physicochemical properties, in vitro release characteristics, and antibacterial activities were analyzed. Results showed that the fabricated liposomes 8-CDCar-Lip and e-PL/8-CD-Car-Lip were nanosized and spherical, and the latter had a larger particle size (152.21 +/- 14.48 to 520.45 +/- 30.69 nm) and greater encapsulation efficiency (69.23 +/- 0.95 to 73.25 +/- 0.65%). The in vitro release study results showed that the rate of release from e-PL-coated liposomes was much lower than that from uncoated liposomes. Inhibition of bacterial growth experiments revealed that the minimum inhibitory concentration of e-PL/8-CD-Car-Lip against Escherichia coli and Staphylococcus aureus (0.025 and 0.05 mg/mL, respectively) was twice as low as that of 8-CD-Car-Lip and nearly 12 times lower than that of Car at the same concentration. The e-polylysine coating increased the diameter, encapsulation efficiency (EE), release time, and antibacterial activity of 8-CD-Car-Lip, and the fabricated complex liposome could be applicable as an additive in the design of antibacterial packaging.

Automated summary

Carvacrol was embedded in cyclodextrin and prepared into liposomes with different concentrations. The e-polylysine coated liposomes showed larger particle size, higher encapsulation efficiency, slower release rate, and stronger antibacterial activity. The findings suggest potential applications in antibacterial packaging design.