Nanoencapsulation of Maqui (Aristotelia chilensis) Extract in Chitosan–Tripolyphosphate and Chenopodin-Based Systems

Abstract

Maqui berries contain a high percentage of anthocyanins with high antioxidant and anti-inflammatory capacity but that are unstable in the colonic site. Nanocarriers based on polysaccharides and/or proteins can protect against the degradation of anthocyanins. The aim of this study was the nanoencapsulation of maqui extract (ME) in chitosan–tripolyphosphate (CTPP-ME), chenopodin (CH-ME), and chenopodin–alginate (CHA-ME). A standardised ME was prepared and then encapsulated in the nanosystems. The physicochemical properties, encapsulation parameters, and the interactions of ME with the nanovehicles were characterised. The cyanidin-3-glucoside released and ORAC activity in phosphate buffer at pH 7.4 were evaluated. The content of ME was 8–9 mg of cyanidin-3-glucoside/g of extract. CTPP with ME at 3% obtained the highest encapsulation efficiency (EE = 91%), and no significant differences were observed in size (274–362 nm), PDI (0.5–0.7), and zeta potential (+34–+41 mV) when the concentration of ME changed from 1% to 5%. CH-ME was shown to be smaller (152 nm) than CTPP-ME, and CH-ME and CHA-ME showed lower EE (79% and 54%, respectively) than CTPP-ME. FT-IR revealed a stronger interaction of ME with CTPP-ME than with CH-ME. Both systems showed a significantly lower release than free ME, and the T50 value of CTPP-ME 3% (328 min) was higher than CH-ME (197 min). Both protected the ORAC activity of ME.

Nanoemulsions Based on Soluble Chenopodin/Alginate Complex for Colonic Delivery of Quercetin

“…This is evidenced by the low T50 values of F1Qt (8.5 h) compared to F4Qt (10.4 h) and P4Qt (12.9 h). Similar results were reported by Andrade et al [ 70 ] who used nanoencapsulation of a maqui extract in chitosan/tpp and QP nanovehicles to obtain a higher T50 (5.46 h) for the formulation with a strong intermolecular interaction with the encapsulated active ingredient. Additionally, it is reported that there is a greater release of Qt by diffusion at pH 5.4 compared to pH 7.4 from the NEs F4Qt and P4Qt.…”

“…The in vitro Qt dissolution of F4Qt, F5Qt, P4Qt, and P5Qt in PBS1X and Krebs buffer fits the Korsmeyer–Peppas model, capable of describing the release of drugs from polymers such as the QPA complex and QP, considering non-Fickian mechanisms [ 69 , 70 ]. See Table S3 .…”

“…On the other hand, F4Qt and P4Qt presented greater release ( p < 0.05) of Qt than F1Qt due to the swelling of the QPA complex and QP that covers the nanodroplet, strongly hydrophilic polymers, favoring the activity of proteases and alginate lyases of the colonic microbiota healthy as B. thetaiotaomicron and in IBD conditions as with E. coli . The effect of swelling of the QPA complex and enzymatic activity of the microbiota was evident in the decrease in T50 values (<10 h), triggering the diffusion of Qt by non-Fickian mechanisms (Korsmeyer–Peppas model) [ 70 , 71 ].…”