Organosolv Treatment of Red Grape Pomace for Effective Recovery of Antioxidant Polyphenols and Pigments Using a Ternary Glycerol/Ethanol/Water System under Mild Acidic Conditions
Abstract
:1. Introduction
2. Results and Discussion
2.1. Single-Factor Experimentation
2.2. Severity-Based Modeling
2.3. Response Surface-Based Modeling
2.4. Assessment of Treatment Performance
2.5. Effect on Polyphenolic Composition and Antioxidant Characteristics
3. Materials and Methods
3.1. Chemicals
3.2. Red Grape Pomace (RGP)
3.3. Extraction Procedures
3.4. Determination of Treatment Severity
3.5. Experimental Design for Treatment Optimization
3.6. Analyses for Total Polyphenols, Total Pigments, Total Flavanols and Antioxidant Properties
3.7. Chromatographic Analyses
3.8. Data Handling and Statistics
4. Conclusions
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Conflicts of Interest
References
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CCA (% w/v) | t (min) | CSF | CSF’ | YTP (mg GAE g−1 DM) |
---|---|---|---|---|
5 | 60 | −0.45 a | 6.55 a | 123.06 a |
180 | 0.03 c | 7.03 c | 126.13 a | |
300 | 0.25 c | 7.25 c | 149.68 c | |
10 | 60 | −0.26 a | 6.74 a | 134.52 c |
180 | 0.22 c | 7.22 c | 145.05 c | |
300 | 0.44 b | 7.44 b | 163.23 b | |
15 | 60 | −0.12 c | 6.88 c | 123.73 a |
180 | 0.36 c | 7.36 c | 145.09 c | |
300 | 0.58 b | 7.58 b | 168.49 b |
Design Point | Independent Variables | Responses | ||
---|---|---|---|---|
YTP (mg GAE g−1 DM) | ||||
X1 (CCA, %) | X2 (t, min) | Measured | Predicted | |
1 | −1 (5) | −1 (60) | 133 | 130 |
2 | −1 (5) | 1 (300) | 150 | 147 |
3 | 1 (15) | −1 (60) | 124 | 126 |
4 | 1 (15) | 1 (300) | 168 | 170 |
5 | −1 (5) | 0 (180) | 126 | 132 |
6 | 1 (15) | 0 (180) | 146 | 141 |
7 | 0 (10) | −1 (60) | 135 | 135 |
8 | 0 (10) | 1 (300) | 165 | 166 |
9 | 0 (10) | 0 (180) | 145 | 144 |
10 | 0 (10) | 0 (180) | 147 | 144 |
11 | 0 (10) | 0 (180) | 140 | 144 |
Compound | Yield (μg g−1 DM) | |||
---|---|---|---|---|
Water | 60% EtOH | 75% Gl | Solvent | |
Non-pigment polyphenols | ||||
Gallic acid | 9.1 ± 0.1 a | nd | 15 ± 2 b | nd |
Caftaric acid | 41.9 ± 0.8 a | 29 ± 1 b | 44 ± 2 a, d | 40 ± 2 a, c |
Catechin | 136 ± 8 a | 69 ± 3 b | 250 ± 10 c | 300 ± 20 d |
p-Coumarate derivative | 14.6 ± 0.8 a | nd | nd | 16 ± 1 a |
Ferulate derivative | 44 ± 1 a | 56 ± 2 b | 55 ± 3 b | 59 ± 6 b |
p-Coumaric acid | 12.5 ± 0.8 a | 12.6 ± 0.5 a | 14.2 ± 0.4 b | 18 ± 2 c |
Ferulic acid | 18 ± 1 a | 19 ± 2 a | 19.2 ± 0.9 a | 26.8 ± 0.4 b |
Rutin | 6.4 ± 0.3 a | 16 ± 1 b | 11.4 ± 0.4 c | 16.5 ± 0.9 b |
Quercetin 3-O-glucuronide | 47 ± 1 a | 99 ± 1 b | 78.9 ± 0.9 c | 83 ± 5 c |
Kaempferol 3-O-rutinoside | nd | 6.7 ± 0.2 a | 2.29 ± 0.08 b | 3.5 ± 0.4 c |
Myricetin | 17.5 ± 0.4 a | 92 ± 4 b | 45.0 ± 0.9 c | 50 ± 4 c |
Resveratrol | 9.4 ± 0.1 a | 21.6 ± 0.8 b | 17.1 ± 0.2 c | 21 ± 1 b |
Quercetin | 19.2 ± 0.2 a | 171 ± 5 b | 109 ± 4 c | 149 ± 9 d |
Kaempferol | 7.8 ± 0.4 a | 32 ± 1 b | 18.9 ± 0.3 c | 30.8 ± 0.6 b |
Isorhamnetin | 9.8 ± 0.1 a | 93 ± 1 b | 46.4 ± 0.4 c | 90 ± 5 b |
Total | 394 | 718 | 730 | 901 |
Anthocyanin pigments | ||||
Cyanidin 3-O-glucoside | 24.2 ± 0.2 a | 27 ± 3 a | 5.3 ± 0.4 b | 13 ± 2 c |
Delphinidin 3-O-glucoside | 65 ± 6 a | 78 ± 3 b | 61 ± 7 c | 115 ± 2 d |
Petunidin 3-O-glucoside | 85 ± 5 a | 390 ± 24 b | 97 ± 8 a | 180 ± 10 c |
Paeonidin 3-O-glucoside | 364 ± 4 a | 730 ± 40 b | 399 ± 6 c | 250 ± 20 d |
Malvidin 3-O-glucoside | 36 ± 2 a | 131 ± 6 b | 65 ± 2 c | 74 ± 7 c |
Malvidin 3-O-glucoside p-coumarate | 58 ± 1 a | 1320 ± 30 b | 315 ± 6 c | 420 ± 30 d |
Total | 631 | 2676 | 942 | 1049 |
Sum | 1025 | 3394 | 1671 | 1950 |
Variable | Code | Levels | ||
---|---|---|---|---|
−1 | 0 | 1 | ||
CCA (%) | X1 | 5 | 10 | 15 |
t (min) | X2 | 60 | 180 | 300 |
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Geropoulou, M.; Yiagtzi, E.; Chatzimitakos, T.; Palaiogiannis, D.; Makris, D.P. Organosolv Treatment of Red Grape Pomace for Effective Recovery of Antioxidant Polyphenols and Pigments Using a Ternary Glycerol/Ethanol/Water System under Mild Acidic Conditions. Molecules 2024, 29, 563. https://doi.org/10.3390/molecules29030563
Geropoulou M, Yiagtzi E, Chatzimitakos T, Palaiogiannis D, Makris DP. Organosolv Treatment of Red Grape Pomace for Effective Recovery of Antioxidant Polyphenols and Pigments Using a Ternary Glycerol/Ethanol/Water System under Mild Acidic Conditions. Molecules. 2024; 29(3):563. https://doi.org/10.3390/molecules29030563
Chicago/Turabian StyleGeropoulou, Maria, Elissavet Yiagtzi, Theodoros Chatzimitakos, Dimitrios Palaiogiannis, and Dimitris P. Makris. 2024. "Organosolv Treatment of Red Grape Pomace for Effective Recovery of Antioxidant Polyphenols and Pigments Using a Ternary Glycerol/Ethanol/Water System under Mild Acidic Conditions" Molecules 29, no. 3: 563. https://doi.org/10.3390/molecules29030563
APA StyleGeropoulou, M., Yiagtzi, E., Chatzimitakos, T., Palaiogiannis, D., & Makris, D. P. (2024). Organosolv Treatment of Red Grape Pomace for Effective Recovery of Antioxidant Polyphenols and Pigments Using a Ternary Glycerol/Ethanol/Water System under Mild Acidic Conditions. Molecules, 29(3), 563. https://doi.org/10.3390/molecules29030563