ABSTRACT
The purpose of this review was to collect relevant chemical data about lycopene and its isomers, which can be extracted using different non-polar or polar aprotic solvents by SC-CO2 or biosynthesis as a friendly technique. Lycopene and other carotenoids can be identified and quantified by UV-Vis and HPLC using a C18 or C30 column, while their characterization is possible by UV-Vis, Fluorescence, FTIR, MS, NMR, and DSC assays. Among these techniques, the last four can compare lycopene isomers and identify cis or all-trans-lycopene. FTIR, MS, and NMR techniques are more suitable for the verification of the purity of lycopene extracts due to the signal complexity generated for each isomer, which enables identification by subtle differences. Additionally, some biological activities of lycopene isolated from red vegetables have already been confirmed, such as anti-inflammatory, antioxidant, and cytotoxic activity against cancer cells, probably by activating several pathways. The encapsulation of lycopene in nanoparticles demonstrated an improvement in oral delivery, and ex vivo assessments determined that these nanoparticles had better permeation and low cytotoxicity against human cells with enhanced permeation. These data suggest that lycopene has the potential to be applied in the food and pharmaceutical industries, as well as in cosmetic products.
ABSTRACT
Silver nanoparticles have been shown to possess considerable antibacterial activity, but in vivo applications have been limited due to the inherent, but low, toxicity of silver. On the other hand, silver nanoparticles could provide cutaneous protection against infection, due to their ability to liberate silver ions via a slow release mechanism, and their broad-spectrum antimicrobial action. Thus, in this work, we describe the development of a carboxymethyl cellulose-based hydrogel containing silver nanoparticles. The nanoparticles were prepared in the hydrogel in situ, utilizing two variants of cashew gum as a capping agent, and sodium borohydride as the reducing agent. This gum is non-toxic and comes from a renewable natural source. The particles and gel were thoroughly characterized through using rheological measurements, UV-vis spectroscopy, nanoparticles tracking analysis, and transmission electron microscopy analysis (TEM). Antibacterial tests were carried out, confirming antimicrobial action of the silver nanoparticle-loaded gels. Furthermore, rat wound-healing models were used and demonstrated that the gels exhibited improved wound healing when compared to the base hydrogel as a control. Thus, these gels are proposed as excellent candidates for use as wound-healing treatments.
