Loading and Release of Phenolic Compounds Present in Mexican Oregano (Lippia graveolens) in Different Chitosan Bio-Polymeric Cationic Matrixes

Abstract

Mexican oregano (Lippia graveolens) polyphenols have antioxidant and anti-inflammatory potential, but low bioaccessibility. Therefore, in the present work the micro/nano-encapsulation of these compounds in two different matrixes of chitosan (CS) and chitosan-b-poly(PEGMA2000) (CS-b-PPEGMA) is described and assessed. The particle sizes of matrixes of CS (~955 nm) and CS-b-PPEGMA (~190 nm) increased by 10% and 50%, respectively, when the phenolic compounds were encapsulated, yielding loading efficiencies (LE) between 90–99% and 50–60%, correspondingly. The release profiles in simulated fluids revealed a better control of host–guest interactions by using the CS-b-PPEGMA matrix, reaching phenolic compounds release of 80% after 24 h, while single CS retained the guest compounds. The total reducing capacity (TRC) and Trolox equivalent antioxidant capacity (TEAC) of the phenolic compounds (PPHs) are protected and increased (more than five times) when they are encapsulated. Thus, this investigation provides a standard encapsulation strategy and relevant results regarding nutraceuticals stabilization and their improved bioaccessibility.

Chitosan as an Outstanding Polysaccharide Improving Health-Commodities of Humans and Environmental Protection

“…In other work, when compared to chitosan, copolymers based on chitosan and polyethylene glycol methyl methacrylate (PEGMA) loaded with phenolic compounds (extracted from oregano) resulted in lower particle size (458 nm), more controlled release patterns in response to pH changes, and higher protection for the active agents in simulated gastric conditions (see the cumulative release profiles in Figure 3 ). However, this study revealed that the carrier system prepared with non-modified chitosan (particle size = 1106 nm) had better loading efficiency and was more stable (zeta potential = 50 mV) than the block copolymers-based system (zeta potential = −15 mV) [ 55 ]. In the same way, the encapsulation of quercetin in platforms developed from chitosan and soybean polysaccharides has resulted in nanoparticles with appropriate size (close to 24 nm) for targeting specific cells in the treatment of numerous diseases; in this case, chitosan helped to obtain a more stable complex [ 56 ].…”

“…The trials were performed in simulated salivary fluids. The figure was taken from the literature [ 55 ].…”

Green Extracts and UPLC-TQS-MS/MS Profiling of Flavonoids from Mexican Oregano (Lippia graveolens) Using Natural Deep Eutectic Solvents/Ultrasound-Assisted and Supercritical Fluids

“…Four flavonoids are flavonols: quercetin, quercitrin, rutin, and kaempferol; two dihydrochalcones identified as phloretin and phloridzin; and one isoflavone identified as genistein (Table 2). The presence of flavonoids in oregano, mostly flavones and flavanones such as apigenin, luteolin-7-glucoside, and naringenin, has been previously reported [21][22][23]. The quantification of flavonoids was carried out based on commercial standards.…”