Table 3.
UAE, SFE, MHG, and DES extraction of phenolic compounds from various agri-food wastes.
| Extraction technique | Fruit or vegetable byproduct | Extraction conditions | Polyphenols extraction yields | References |
|---|---|---|---|---|
| Ultrasound assisted extraction (UAE) | Artichoke waste | Solid-to-liquid ratio (S/L) 333 g/L in H2O, 60 min, 50W/L |
TPC 0.8–1.4 mg GAE/g | (207) |
| S/L 100 g/L, 50% ethanol, 25°C, 60 min, 240. | 0.02–14.8 mg chlorogenic acid/g | (208) | ||
| Cauliflower waste | S/L 50 g/L, 2 M NaOH, 60°C, 15 min, 37 kHz, 180 W | TPC 7.3 mg GAE/g | (209) | |
| Tobacco waste | S/L 20-100 g/L, ethanol-H2O 60:40–20:80 v/v, 30–70°C, 15–45 min, 37 kHz, 50 W | 3.6–804.2 μg/mL of chlorogenic acid 2.34–10.8 μg/mL of caffeic acid 11.6-93.7 μg/mL of rutin |
(210) | |
| Mustard seed meal | S/L 25 g/L, 70% ethanol, 40°C, 30 min, 60 W | TPC 13.8 mg sinapic acid equivalents/g | (211) | |
| Microwave hydrodiffusion and gravity (MHG) | Broccoli waste | 43 min, 500 W, under atmospheric pressure, in the absence of solvents | 317 μg GAE/mL | (212) |
| Sea buckthorn pomace | 15 min, 400 W | 1147 mg GAE/g | (213) | |
| Supercritical fluid extraction (SFE) | Blueberry waste | Flow rate 0.5 kg/h 5% ethanol + 5% H2O as co-solvents, 20 MPa, 40°C |
TPC 134 mg GAE/g | (214) |
| Deep eutectic solvent (DES) extraction | Ginkgo biloba leaves | S/L 95 g/L, ChCl/malonic acid 1:2 mol/mol + 55% H2O, 65°C, 53 min | 22.2 mg proanthocyanidins/g | (215) |
| Moringa oleifera leaves | S/L 50 g/L, glycerol/sodium acetate 6:1 mol/mol + 20% H2O, 50°C, 180 min | TPC 53.8 mg GAE/g TFC 16.5 mg RE/g |
(216) | |
| Peanut roots | S/L 33 g/L, ChCl/1,4-butanediol 1:3 mol/mol + 40% H2O, 55°C, 40 min | 38.9 mg of resveratrol/kg of sample | (217) | |
| Rue leaves | S/L 50 g/L, ChCl/citric acid 2:1 mol/mol + 20% H2O,30°C, 90 min. | 38.2 mg GAE/g | (218) | |
| Mango waste | S/L 17 g/L, lactic acid/sodium acetate/ H2O 3:1:4 mol/mol/mol, 20 min, 436 W | 56.2 mg GAE/g | (219) |