Table 1.
Dietary fibers, total phenols and total flavonoids in industrial fruit and vegetable byproducts and their antioxidant activity.
| Products | Byproducts | Total Dietary Fibers (%) | Insoluble Dietary Fibers (%) | Soluble Dietary Fibers (%) | Total Phenol (mg GAE 100 g−1 DM) | Total Flavonoids (mg QE 100 g−1 DM) | Antioxidant Activity | References | ||
|---|---|---|---|---|---|---|---|---|---|---|
| DPPH (mmol TE 100 g−1 DM) | ABTS (mmol TE 100 g−1 DM) | Others | ||||||||
| Apple | Seed | - | - | - | 286.1–514.1 | - | 2.14–4.35 | 9.15–39.79 | - | [11] |
| Peel | - | - | - | 564 | 303 | 22 ± 0.00 a | - | - | [12] | |
| Pomace | - | - | - | 348 | - | 72.6 ± 1.6 a | 84.3 ± 1.6 a | - | [13] | |
| Avocado | Seed | - | - | - | 57.3 | - | 41.07 ± 3.58 | 64.58 ± 1.79 | 65.69 ± 2.6 d (FRAP) | [14] |
| Peel | - | - | - | 63.5 | - | 31.0 ± 3.69 | 79.15 ± 3.59 | 117.51 ± 10.29 d (FRAP) | [14] | |
| Banana | Peel | 64.3 | 56.8 | 7.4 | 1500.2 | 900.3 | IC50: 55.23 b | - | 1.41 e (Cu2+ reduction) | [15] |
| Pomegranate | Peel | - | - | - | 45.7 | - | 92.09 ± 0.36 a | 97.14 ± 0.17 a | - | [16] |
| Dates | Seed | 9.5 | - | - | 442.1 | - | 87.23 ± 1.3 a | - | - | [17] |
| Mango | Seed | - | - | - | ca. 1920 | ca. 290 | ca. 90 c | ca. 620 c | - | [18] |
| Peel | 69.8 | 44.2 | 24.6 | 4500 | - | - | - | 6.96 f | [19] | |
| Pulp | - | 43.1 | 20.9 | 100 | 28.2 | - | - | - | [20] | |
| Citrus | Seed | - | - | - | 7.8 | - | IC50: 5.53 ± 0.08 b | - | 0.92 ± 0.01 g (AC) | [21] |
| Peel | 67.4 | 62.4 | 4.9 | 145.5 | - | 22.4 ± 0.07 | - | 2.24 ± 0.07 g (AC) | [22] | |
| Tomato | Pomace | - | - | - | 86.5 | - | - | - | 2.46 ± 0.3 g (AC) | [23] |
| Carrot | Pomace | - | - | - | ca. 500 | ca. 320 | 35 c | - | 45 c (CUPRAC) | [24] |
(-), not available. a Percentage (%) of DPPH or ABTS radical inhibition, b (µg mL−1) at 50% scavenging of DPPH radical, c mg TE g−1 DM, d mmol Fe2+ 100g−1 DM, e µM TR g−1 DM, f µgVit-C Eq. g−1 DM, g mmol TE kg−1 DM. DPPH: 2,2-diphenyl-1-picrylhydrazyl. ABTS: 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid). FRAP: ferric reducing antioxidant power. TR: trolox equivalent. AC: antioxidant capacity. IC50: median inhibition concentration. GAE: gallic acid equivalent. QE: quercetin equivalent. DM: dry matter. CUPRAC: CUPric reducing antioxidant capacity assay.