In vitro release and antioxidant activity of Satsuma mandarin (Citrus reticulata Blanco cv. unshiu) peel flavonoids encapsulated by pectin nanoparticles

Abstract

The flavonoids of citrus peel extracts (CPE) were encapsulated by pectin nanoparticles (PNs), in an attempt to control the releasing property and improve their antioxidant activity. The physiochemical properties of the obtained PNs were characterised. Flavonoid composition in CPE before and after encapsulation were determined. In vitro release profiles and antioxidant activity of CPE were further evaluated. Results showed the size of spherical PNs obtained was 271.5 AE 5.3 nm. Interestingly, in simulated gastric fluid (SGF), 73% flavonoids were released from the naked CPE after 2 h, while only 28.78% from the CPE-loaded PNs (E-PNs). The releasing rate of flavonoids reached 91.47% from E-PNs after 24 h in the simulated intestinal fluid (SIF). Moreover, DPPH and ABTS assay revealed that E-PNs showed higher antioxidant activity than blank PNs and free CPE. These data showed that the controlled release of CPE might potentially increase its bioaccessibility and there was a synergistic effect between citrus PNs and CPE on the antioxidant activity. Encapsulation, release, antioxidant activity Y. Hu et al. Encapsulation, release, antioxidant activity Y. Hu et al.Figure 6 Comparison of antioxidant activity of CPE by DPPH• + (a) and ABTS• + (b) and antioxidant activity of E-PNs and pectin by DPPH• + (c) and ABTS• + (d) at different concentrations, data are reported as means AE SD, n = 3. Encapsulation, release, antioxidant activity Y. Hu et al.

Optimized preparation process for naringenin and evaluation of its antioxidant and α‐glucosidase inhibitory activities

“…Furthermore, the Adeq Precision value (13.994) is higher than 4, which indicates an adequate signal. These results indicate that the experimental design of the model was feasible and effective (Hu et al., 2017). In addition, the linear coefficients ( A , C ), quadratic term coefficients ( A 2 , B 2 , and C 2 ), and cross‐product coefficients ( AC ) were significant, indicating the significance of their effects on the conversion of naringin.…”

“…The DPPH radical‐scavenging test is widely used to evaluate natural products or synthetic compounds because of its advantages of operational ease and accurate experimental results (Hu et al., 2017). As shown in Figure 6a, both naringenin and naringin have the ability to scavenge DPPH free radicals and have a definite effect on the concentration.…”

“…ANOVA was used to validate the regression equation and determine the effect of each factor on the conversion of naringin. As shown in Table 3 (Hu et al, 2017). In addition, the linear coefficients (A, C), quadratic term coefficients (A 2 , B 2 , and C 2 ), and cross-product coefficients (AC) were significant, indicating the significance of their effects on the conversion of naringin.…”

Evaluation of antioxidant properties of extractable and nonextractable polyphenols in peel and flesh tissue of different peach varieties

“…However, on the other hand, according to many studies, phenolic compounds are accumulated in the epidermal layer (peel) of the fruit at the tissue level (Cevallos‐Casals, Byrne, Okie, & Cisneros‐Zevallos, ). For example, many fruit such as pear, blueberry, apple, citrus, and mango, their peel tissues contain higher quantities of phenolic compounds as compared with flesh (Abbasi et al, ; Hu, Zhang, Ke, Li, & Zhou, ; Kim et al, ; Li et al, ; Vieira et al, ; Wang, Camp, & Ehlenfeldt, ). Previous studies have pointed out that the external concentration of phenolics is involved in protection of plant cells against pathogens and environmental stress (Treutter, ).…”

Potential of Nanomaterial Applications in Dietary Supplements and Foods for Special Medical Purposes

“…Citrus reticulata Blanco cv. unshiu peel extract (CPE) flavonoids encapsulated by pectin NPs with particle size 271.5 ± 5.3 nm released only 28.78% of flavonoids in simulated gastric fluid within 2 h compared to naked CPE and showed higher antioxidant activity than blank pectin NPs and free CPE [ 140 ]. The replacement of 30% of pectin (low charge density) with alginate (high charge density) forming shell around zein NPs significantly improved the aggregation stability at pH 5–7 and high ionic strengths (2.0 µM NaCl), and CUR encapsulated in these core-shell NPs was characterized by higher antioxidant and radical scavenging activities than CUR dissolved in ethanol solutions [ 141 ].…”