Bioactive Phenolics and Antioxidant Capacity of Some Wild Edible Greens as Affected by Different Cooking Treatments
Abstract
:1. Introduction
2. Materials and Methods
2.1. Chemicals
2.2. Plant Material
2.3. Sample Preparation
2.4. Cooking Conditions
- Boiling. Each sample was immersed in 2 L of boiling tap water in a covered stainless steel pot and cooked on electric heating plate (ARED Heating Magnetic Stirrer, Velp Scientifica, Usmate Velate, MB, Italy). Cooking times: 10 min for B. vulgaris, H. echioides, S. oleraceus; 8 min for A. acutifolius; 7 min for A. lutea, T. officinale, U. picroides; 3 min for U. dioica.
- Steaming. Each sample was placed in a stainless steel steam cooker, suspended in a basket, covered with a lid, and steamed with 500 mL of boiling water at atmospheric pressure using an electric heating plate (ARED Heating Magnetic Stirrer, Velp Scientifica, Usmate Velate, MB, Italy). Cooking times: 4 min for A. acutifolius, 3 min for U. dioica, and 7 min for the other species.
- MW-cooking. Each sample was placed in a glass pot with 200 mL of water. Pots were covered with a micro-perforated plastic film and cooked at 900 W in a commercial microwave oven (mod. MWO 112-WH, 50 Hz, Whirlpool Co., Benton Harbor, MI, USA). Cooking times were as for steaming.
2.5. Dry Matter Determination
2.6. Preparation of Phenolic Extracts
2.7. Total Phenols
2.8. HPLC-DAD Analysis of Phenolic Compounds
2.9. Antioxidant Capacity
2.10. Statistical Analysis
3. Results and Discussion
3.1. Dry Matter Content
3.2. Phenolic Composition of Raw Wild Greens
3.3. The Effect of Cooking on Total Phenolic Content
3.4. The Effect of Cooking on Individual Phenolic Compounds
3.5. The Effect of Cooking on Antioxidant Activity
3.6. The Whole Impact of Cooking on Antioxidant Properties of the Wild Edible Greens
4. Conclusions
Author Contributions
Funding
Acknowledgments
Conflicts of Interest
References
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Scientific Name | Family Name | Common Name | Used Part | Traditional Uses |
---|---|---|---|---|
Asparagus acutifolius L. | Liliaceae | Wild Asparagus | Stems | Boiled, fried, omelets, soup, pickles, in oil |
Asphodeline lutea (L.) Rchb. | Liliaceae | Yellow Asfodel | Stems, roots | Salad, boiled, fried, grilled, omelets |
Beta vulgaris subsp. maritima (L.) Arcang. | Chenopodiaceae | Common Beet | Leaves, stems | Salad, boiled, vegetable pie |
Helminthotheca echioides L. | Asteraceae | Bristy Ox-Tongue | Leaves, stems, roots | Salad, boiled |
Sonchus oleraceus L. | Asteraceae | Sow Thistle | Leaves, stems, flowers | Salad, boiled, soup, vegetable pie |
Taraxacum officinale Weber | Asteraceae | Common Dandelion | Leaves, roots, flowers, germ | Salad, boiled, fried, soup, vegetable pie, pickles, in oil |
Urospermum picroides (L.) Schmidt | Asteraceae | Prickly Golden Fleece | Leaves, stems | Boiled |
Urtica dioica L. | Urticaceae | Stinging Nettle | Leaves, stems, flowers | Boiled, fried, omelets, soup, vegetable pie |
Peak Number | Retention Time (a) (min) | λmax (b) (nm) | Phenolic Compound Identity (c) | Phenolic Compound Content (mg 100g −1 DM) | |||||||
---|---|---|---|---|---|---|---|---|---|---|---|
Species | |||||||||||
Asparagus acutifolius | Asphodeline lutea | Beta vulgaris | Helminthotheca echioides | Sonchus oleraceus | Taraxacum officinale | Urospermum picroides | Urtica dioica | ||||
1 | 5.15 | 326 | neo-CHLA | 56 ± 7 | |||||||
2 | 5.81 | 275 | unknown 1 | 172 ±13 | |||||||
3 | 5.87 | 327 | CFTA | 63 ± 5 | 109 ± 11 | 114 ± 10 | |||||
4 | 8.18 | 326 | CHLA | 55 ± 5 | 23 ± 3 | 66 ± 8 | 29 ± 3 | 1355 ± 148 | 563 ± 67 | ||
5 | 8.29 | 303 | unknown 2 | 18 ± 3 | |||||||
6 | 9.80 | 326 | CA-der. 1 | 12 ± 3 | 14 ± 4 | ||||||
7 | 10.80 | 325 | CA (I.S.) | tr.(d) | tr.(d) | tr.(d) | tr.(d) | ||||
8 | 11.77 | 315 | unknown 3 | 15 ± 4 | |||||||
9 | 12.71 | 327 | CA-der. 2 | tr.(d) | tr.(d) | 28 ± 4 | tr.(d) | ||||
10 | 13.93 | 325 | CA-der. 3 | 18 ± 5 | |||||||
11 | 16.45 | 331 | CHCA | 65 ± 7 | 301 ± 42 | 725 ± 85 | 625 ± 72 | ||||
12 | 16.93 | 255; 349 | L-der. 1 | 50 ± 4 | |||||||
13 | 18.00 | 267; 344 | unknown 4 | 17 ± 3 | |||||||
14 | 20.01 | 269; 338 | A-der. 1 | 1600 ± 192 | |||||||
15 | 21.31 | 269; 338 | A-der. 2 | 115 ± 9 | |||||||
16 | 21.20 | 326 | 3,5-DCQA | 11 ± 4 | 25 ± 2 | 64 ± 5 | 40 ± 5 | 110 ± 13 | |||
17 | 22.25 | 326 | 1,5-DCQA | 14 ± 5 | |||||||
18 | 22.53 | 256; 351 | L-7-glucoside | 149 ± 18 | 115 ± 12 | 444 ± 51 | 11 ± 3 | ||||
19 | 22.92 | 257; 356 | Q-3-glucoside | 412 ± 48 | |||||||
20 | 23.65 | 257; 356 | Q-3-rutinoside | 299 ± 27 | 147 ± 16 | ||||||
21 | 24.96 | 269; 337 | A-der. 3 | 672 ± 55 | |||||||
22 | 25.56 | 257; 356 | Q-der. | 133 ± 18 | tr.(d) | ||||||
23 | 25.90 | 256; 352 | I-der. | 122 ± 15 | |||||||
24 | 27.50 | 317 | unknown 5 | 28 ± 5 | |||||||
25 | 27.67 | 268; 339 | A-7-glucoside | 19 ± 3 | 59 ± 8 | 544 ± 67 | |||||
26 | 28.33 | 255; 349 | L-der. 2 | 18 ± 4 | |||||||
27 | 28.83 | 266; 349 | K-3-rutinoside | 18 ± 4 | |||||||
28 | 29.85 | 256; 351 | L-der. 3 | 21 ± 5 | |||||||
29 | 29.97 | 255; 356 | I-3-rutinoside | 215 ± 18 | |||||||
30 | 39.66 | 255; 351 | L-der. 4 | 69 ± 8 | |||||||
31 | 43.88 | 317 | unknown 6 | 64 ± 10 | |||||||
32 | 44.02 | 319 | unknown 7 | 35 ± 4 | |||||||
33 | 45.32 | 303 | unknown 8 | 29 ± 2 | |||||||
34 | 50.38 | 275 | unknown 9 | 36 ± 4 |
Species | Total Phenolic Content (TPC) (mg CAE 100g−1 DM) | |||
---|---|---|---|---|
Raw | Boiling | Steam | Microwave | |
A. acutifolius | 1200 ± 57 b,A | 873 ± 33 d,B | 1196 ± 60 d,A | 1136 ± 52 c,A |
A. lutea | 1055 ± 52 c,A | 756 ± 42 d,B | 955 ± 60 e,A | 777 ± 53 d,B |
B. vulgaris | 2477 ± 255 a,A | 1443 ± 81 b,B | 2375 ± 108 b,A | 1962 ± 264 b,AB |
H. echioides | 810 ± 115 d,C | 1410 ± 117 bc,AB | 1184 ± 124 d,B | 1495 ± 268 c,A |
S. oleraceus | 1394 ± 231 b,B | 644 ± 44 de,C | 2005 ± 212 c,A | 2371 ± 472 b,A |
T. officinale | 1044 ± 265 bcd,A | 1108 ± 212 c,A | 1315 ± 210 d,A | 1151 ± 192 c,A |
U. picroides | 2574 ± 247 a,BC | 2109 ± 245 a,C | 2811 ± 152 a,B | 4632 ± 104 a,A |
U. dioica | 735 ± 87 d,A | 184 ± 65 f,C | 443 ± 73 f,B | 326 ± 75 e,BC |
Cooking Method | TPC | Chlorogenic Acid | Chicoric Acid | Caftaric Acid | Apigenin-7-Glucoside | Luteolin-7-Glucoside | Sum of Caffeic Acid Derivatives | Sum of Flavonoids |
---|---|---|---|---|---|---|---|---|
Raw | ** | ns | ns | ns | ns | *** | * | ns |
Boiling | *** | ** | ns | * | ns | ns | * | * |
Steam | *** | ns | ns | ns | * | *** | ** | ns |
Microwave | **** | ** | ns | ns | * | *** | ** | * |
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Sergio, L.; Boari, F.; Pieralice, M.; Linsalata, V.; Cantore, V.; Di Venere, D. Bioactive Phenolics and Antioxidant Capacity of Some Wild Edible Greens as Affected by Different Cooking Treatments. Foods 2020, 9, 1320. https://doi.org/10.3390/foods9091320
Sergio L, Boari F, Pieralice M, Linsalata V, Cantore V, Di Venere D. Bioactive Phenolics and Antioxidant Capacity of Some Wild Edible Greens as Affected by Different Cooking Treatments. Foods. 2020; 9(9):1320. https://doi.org/10.3390/foods9091320
Chicago/Turabian StyleSergio, Lucrezia, Francesca Boari, Maria Pieralice, Vito Linsalata, Vito Cantore, and Donato Di Venere. 2020. "Bioactive Phenolics and Antioxidant Capacity of Some Wild Edible Greens as Affected by Different Cooking Treatments" Foods 9, no. 9: 1320. https://doi.org/10.3390/foods9091320