Chitosan-coated liposomes of Carissa spinarum extract: synthesis, analysis and antipneumococcal potency

Abstract

In the present study, a chitosan-coatedCarissa spinarum-polyphenol-loaded liposome (LipCsP-chitosan) nanocarrierwas fabricated for the delivery ofC. spinarumpolyphenols (CsPs) to improve the bioavailability andantipneumococcal potential of CsPs againstKlebsiella pneumoniae. LipCsP-chitosan was synthesized using the iongelation method and characterized by using a Malvern Zetasizer and Fourier transform infrared (FTIR) spectroscopy.CsP encapsulation and release kinetics were investigated. The antipneumococcal activity of the nanoformulationswas assessed using agar-well diffusion and microdilution assays. LipCsP-chitosan exhibited a hydrodynamic size anda zeta potential of 365.22 ± 0.70 nm and +39.30 ± 0.61 mV, respectively. The encapsulation efficiency of LipCsP-chitosan was 81.5%. FTIR analysis revealed interactions of the liposomes with chitosan and CsPs. A biphasic CsPrelease profile followed by a sustained-release pattern was observed. LipCsP-chitosan presented a higherbioaccessibility of polyphenols in the simulated gastric phase (74.1 ± 1.3%) than in the simulated intestinal phase(63.32 ± 1.00%). LipCsP-chitosan had a relative inhibition zone diameter of 84.33 ± 2.51% when compared with CsPs.At a minimum inhibitory concentration of 31.25 mg/ml, LipCsP-chitosan reduced the viability ofK. pneumoniaeby57.45 ± 3.76% after 24 h. The results obtained from this study offer a new approach to the utilization of LipCsP-chitosan as nanocarriers for candidate antipneumococcal agents.