Spirulina sp. LEB 18-extracted phycocyanin: Effects on liposomes' physicochemical parameters and correlation with antiradical/antioxidant properties.

This study describes the physicochemical properties of soybean asolectin (ASO) liposomes loaded with phycocyanin (Phy) extracted from Spirulina sp. LEB 18. The effects of Phy in the liposomes' properties were investigated by Fourier transform infrared spectroscopy (FTIR), 1H and 31P nuclear magnetic resonance (NMR), zeta (ζ)-potential, dynamic light scattering (DLS) and ultraviolet-visible (UV-vis) techniques. Phy restricted the motion of ASO polar and interface groups and disrupted the package arrangement of the lipid hydrophobic regions, as a likely effect of dipolar and π interactions related to its amino acid residues and pyrrole portions. These interactions were correlated to antiradical/antioxidant Phy responses obtained by 2,2-diphenyl-1-picrylhidrazil (DPPH) assay, thiobarbituric acid reactive substances (TBARS) and ferric reducing antioxidant power (FRAP) methods, and discussed to bring new chemical perspectives about Phy-loaded liposomes-related nutraceutical applications in inflammatory and viral infection processes.

Diethyldithiocarbamate loaded in beeswax-copaiba oil nanoparticles obtained by solventless double emulsion technique promote promastigote death in vitro.

Leishmaniasis is considered a neglected tropical disease that represents a Public Health problem due to its high incidence. In the search of new alternatives for Leishmaniasis treatment diethyldithiocarbamate (DETC) has shown an excellent leishmanicidal activity and the incorporation into drug carrier systems, such as solid lipid nanoparticles (SLNs), is very promising. In the present work DETC loaded in beeswax nanoparticles containing copaiba oil were obtained by the double emulsion/melt technique. The nanoparticles were characterized and leishmanicidal activity against L. amazonensis promastigotes forms and cytotoxicity in murine macrophages were evaluated. SLNs presented size below 200 nm, spherical morphology, negative charge surface, high encapsulation efficiency, above 80%, and excellent stability. Moreover, Fourier transform infrared spectroscopy (FTIR) and differential scanning calorimetry (DSC) analyses were performed to evaluate the chemical structure and possible interactions between DETC and SLNs. SLNs provided a protection for DETC, decreasing its cytotoxic effects in macrophages, which led to an improvement in the selectivity against the parasites, which almost doubled from free DETC (11.4) to DETC incorporated in SLNs (18.2). These results demonstrated that SLNs had a direct effect on L. amazonensis promastigotes without affect the viability of macrophage cell, can be a promising alternative therapy for the cutaneous treatment of L. amazonensis.