Table 2.
Phenolic compound extraction processes presented in this review.
| Source | DES Used (Molar Ratio) |
Co-Solvent | Extraction Method and Conditions | Yield | Reference |
|---|---|---|---|---|---|
| Manuka leaves (Leptospermum scoparium) | ChCl:Lactic acid (1:2) |
- | Heating and stirring Temperature: 50 °C Extraction time: 67 min Liquid-solid ratio: 100:5.07 |
TPC: 59.82 mg GAE g−1 | [57] |
| Polygonum cuspidatum root | TBAC:Ethylene glycol (1:3) |
40% water 4.5% HCl |
Heating and stirring Temperature: 80 °C Extraction time: 80 min Rotational speed: 500 rpm Liquid–solid ratio: 40:1 |
Resveratrol: 12.26 ± 0.14 mg g−1 | [58] |
| Buddleja globosa Hope leaves | ChCl:Lactic acid (1:1) |
20% water | Heating and stirring Temperature: 60 °C Extraction time: 50 min Rotational speed: 340 rpm Liquid–solid ratio: 100:1 |
TPC: ca. 175 mg GAE g−1
Luteolin 7-O-glucoside: ca 4.1 mg g−1 Verbascoside: ca. 39 mg g−1 |
[59] |
| L-proline:Citric acid (1:1) |
20% water | TPC: ca. 175 mg GAE g−1
Luteolin 7-O-glucoside: ca. 4 mg g−1 Verbascoside: 51.045 mg g−1 |
|||
| Rosemary leaves (Rosmarinus officinalis L.) | ChCl:1,2-propanediol (1:2) |
50% water | Heating and stirring Temperature: 65 °C Extraction time: 15 min Rotational speed: 600 rpm Liquid–solid ratio: 40:1 |
TPC: 78 mg GAE g−1 | [60] |
| Black mustard (Brassica nigra L.) seed | TEOA:Glycerol (1:2) |
25% ethanol | Heating and stirring Temperature: 65 °C Extraction time: 180 min Rotational speed:1000 rpm Liquid–solid ratio: 10:1 |
TPC: 32.2 ± 0.2 mg GAE g−1 TFC: 7.2 ± 0.2 mg QE g−1 |
[61] |
| TEOA:Propylene glycol (1:2) | 25% ethanol | TPC: 29.3 ± 0.3 mg GAE g−1 TFC: 7.4 ± 0.3 mg QE g−1 |
|||
| Coffee | L-serine:Lactic acid (1:4) |
30% methanol | Two-phase hollow fiber-liquid microextraction (HF-LPME) Fiber material: polypropylene HF DES immersion time: 30 s Rotational speed: 840 rpm |
Caffeic acid: 0.032 µg g−1 | [62] |
| Green Tea | Caffeic acid: 0.022 µg g−1 | ||||
| Tomato | Caffeic acid: 0.012 µg g−1 | ||||
| Green tea | ChCl:ethylene glycol (1:2) |
29% water | Heating and stirring Temperature: 84 °C Extraction time: 39 min Liquid–solid ratio: 44:1 |
Phenolic extraction yield: 20.12% | [63] |
| Radix et Rhixoma Rhei | 1- tetradecanol:10-undecenoic acid (1:4) |
10% HCl | Heating and stirring Temperature: 67 °C Extraction time: 20 min Rotational speed: 500 rpm Liquid–solid ratio: 12:1 |
Anthraquinones: 21.52 mg g−1 | [64] |
| Turmeric (Curcuma longa) | Sucrose:Lactic acid:Water (1:5:7) |
- | Microwave-assisted extraction Temperature: 68.2 °C Extraction time: 15.4 min Maximum power: 1500 W Liquid–solid ratio: 14.5:2 |
Curcumin: 32.00 mg g−1 |
[65] |
| Lour (Osmanthus fragrans) flower | Lactic acid:glucose (1:5) |
85% water | Microwave-assisted extraction Extraction time: 0.5 s Power: 500 W Liquid–solid ratio: 30:1 |
TPC: 192.20 ± 1.08 mg GAE g−1 TFC: 560.13 ± 0.51 mg RE g−1 |
[66] |
| Microwave-assisted extraction Extraction time: 60.00 s Power: 500 W Liquid–solid ratio: 38.41:1 |
TPC: 238.09 ± 0.81 mg GAE g−1 TFC: 321.07 ± 1.65 mg RE g−1 |
||||
| Orange peel waste | ChCl:Ethylene glycol (1:2) |
50% water | Stirring Extraction time: 7 days Rotational speed: 850 rpm Liquid–solid ratio: 5:1 |
Polyphenols: 45.7 mg g−1 | [67] |
| Brewer’s spent grain | ChCl:Glycerol (1:2) |
37.46% water | Microwave-assisted extraction Temperature: 100 °C Extraction time: 13.3 min Maximum power: 700 W |
TPC: 2.89 mg GAE g−1 | [68] |
| Maritime Pine (Pinus pinaster) wood | Lactic acid:Tartaric acid:ChCl (4:1:1) |
- | Heating and stirring Temperature: 175 °C Extraction time: 90 min Liquid–solid ratio: 10:1 |
Lignin removal: 94.9 ± 3.3% | [69] |
| Poplar (Populus) sawdust | ChCl:Lactic acid (1:10) |
- | Heating and stirring Temperature: 130 °C Extraction time: 90 min Liquid–solid ratio: 10:1 |
Lignin removal: 89.3% |
[70] |
| Oil palm (Elaeis guineensis) frond | ChCl:Urea (1:2) |
20% water 2.5% NaOH |
Ultrasound-assisted extraction Extraction time: 30 min Ultrasound amplitude: 60% |
Lignin removal: 47.00 ± 0.16% | [71] |
| Blueberry (Vaccinium spp.) pomace | ChCl:Oxalic acid (1:1) |
30% water | Pulse- Ultrasound-assisted extraction Temperature: 76 °C Extraction time: 3.2 min Power: 325 W Liquid–solid ratio: 60:1 |
Total anthocyanin yield: 24.27 ± 0.05 mg C3GE g−1 | [72] |
| Lily (Lilium lancifolium Thunb.) | ChCl:Ethylene glycol (1:2) |
20% water | Ultrasound-assisted extraction Temperature: 50 °C Extraction time: 40 min Liquid–solid ratio: 25:1 |
Regaloside B: 0.31 ± 0.06 mg g−1 Regaloside C: 0.29 ± 0.03 mg g−1 Regaloside E: 3.04 ± 0.38 mg g−1 |
[73] |
| Lavandula pedunculata subsp. lusitanica | Proline:Lactic acid (1:1) |
30% water | Ultrasound-assisted extraction Extraction time: 60 min Frequency: 37 kHz |
TPC: 56.00 ± 0.77 mg GAE g−1 | [74] |
| Sage (Salvia officinalis) | ChCl:Lactic acid (1:2) |
10% water | Stirring and heating Temperature: 50 °C Extraction time: 90 min |
Carnosic acid: 14.43 ± 0.28 μg mg−1 Carnosol: 4.83 ± 0.09 μg mg−1 |
[75] |
| ChCl:Lactic acid (1:2) |
10% water | Ultrasound-assisted extraction Temperature: 70 °C Extraction time: 60 min |
Carnosic acid: 14.00 ± 0.02 μg mg−1 Carnosol: 4.18 ± 0.05 μg mg−1 |
||
| ChCl:Lactic acid (1:2) |
10% water | MCE Extraction time: 2 min Vibration speed: 5 m s−1 |
Carnosic acid: 8.26 ± 0.45 μg mg−1 Carnosol: 1.87 ± 0.33 μg mg−1 |
||
| Turmeric (Curcuma longa) | ChCl:Lactic acid (1:1) |
20% water | Ultrasound-assisted extraction—direct sonication Temperature: 30 °C Extraction time: 20 min Frequency: 22 kHz Intensity: 70.8 W cm−2 Pulse mode: 60% Particle size: 0.355 mm Liquid–solid ratio: 20:1 |
Curcuminoids: 77.13 mg g−1 | [76] |
| Olive leaf | ChCl:Fructose:Water (5:2:5) |
42.69% water | Ultrasound-assisted extraction Temperature: 75 °C Extraction time: 60 min Power: 140 W Frequency: 37 kHz Liquid–solid ratio: 40.66:1 |
TPC: 187.31 ± 10.3 mg GAE g−1 TFC: 12.75 ± 0.6 mg ApE g−1 |
[77] |
| Helichrysum arenarium L. inflorescences | ChCl:1,2-propanediol (1:2) |
25% water | Ultrasound-assisted extraction Temperature: 50 °C Extraction time: 60 min |
Phenolics: 30.15 ± 0.42 mg g−1 | [78] |
| ChCl:1,4-butanediol (1:6) |
Phenolics: 29.75 ± 0.49 mg g−1 | ||||
| Olive oil | ChCl:Xylitol:Water (2:1:3) |
- | Heating and stirring Temperature: 40 °C Extraction time: 60 min Liquid:oil ratio: 1:1 |
Phenolics: 555.36 ± 21.93 mg kg−1 | [79] |
| Olive oil | ChCl:Extracted phenolics | - | Rotating disk sorptive extraction Extraction time: 15 min Disk material: poly(vinylidene fluoride-co-tetrafluoroethylene) Rotational speed: 150 rpm ChCl concentration: 300 g L−1 |
Absolute extraction recovery Gallic acid: 87% Protocatechuic acid: 79% Tyrosol: 76% Vanillic acid: 75% p-coumarinic acid: 82% Syringaldehyde: 81% Thymol: 66% |
[80] |