Phenolic Compounds from Irradiated Olive Wastes: Optimization of the Heat-Assisted Extraction Using Response Surface Methodology
Abstract
:1. Introduction
2. Materials and Methods
2.1. Standards and Reagents
2.2. Olive Pomace Samples
2.3. Irradiation Experiments
2.4. Heat-Assisted Extraction (HAE)
2.5. Analysed Responses
2.5.1. Extraction Yield
2.5.2. Phenolic Fingerprinting and Quantification
2.6. Extraction Optimization by Response Surface Methodology
2.6.1. Screening Test of Factors and Level Range for Phenolic Compounds Extraction
2.6.2. Experimental Design
2.7. Statistical Analysis
3. Results and Discussion
3.1. Single-Factor Effects for Polyphenolic Extractions
3.1.1. Effect of Extraction Time on Polyphenolic Content and Extractability Yield
3.1.2. Effect of Solvent Concentration on Polyphenolic Content and Extractability Yield
3.2. Optimization of HAE Process in Olive Pomace
3.2.1. Extracting Modelling and Analysis of Variance
3.2.2. Factorial and General Optimization
4. Conclusions
Author Contributions
Funding
Acknowledgments
Conflicts of Interest
References
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Factors | Responses | ||||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Run | X1 | X2 | X3 | X1:t min | X2: T °C | X3: S % | Y1 | Y2 | Y3 | Y4 | Y5 | Y6 | Y7 | Y8 | Y9 | Y10 | Y11 |
1 | −1 | −1 | −1 | 40.3 | 37.2 | 20.3 | 4.28 | 10.23 | 2.08 | 0.21 | 16.79 | 27.01 | 63.36 | 12.92 | 1.28 | 104.57 | 16.12 |
2 | −1 | −1 | 1 | 40.3 | 37.2 | 79.7 | 2.19 | 7.25 | 1.72 | 0.16 | 11.31 | 20.08 | 75.23 | 15.81 | 1.57 | 112.70 | 10.90 |
3 | −1 | 1 | −1 | 40.3 | 72.8 | 20.3 | 5.26 | 12.93 | 2.55 | 0.24 | 20.98 | 28.05 | 69.41 | 14.33 | 1.40 | 113.18 | 16.98 |
4 | −1 | 1 | 1 | 40.3 | 72.8 | 79.7 | 3.23 | 11.35 | 2.37 | 0.23 | 17.18 | 23.84 | 88.49 | 18.41 | 1.71 | 132.44 | 13.23 |
5 | 1 | −1 | −1 | 99.7 | 37.2 | 20.3 | 3.98 | 9.61 | 2.09 | 0.19 | 15.87 | 28.34 | 69.60 | 15.13 | 1.40 | 114.47 | 13.81 |
6 | 1 | −1 | 1 | 99.7 | 37.2 | 79.7 | 2.21 | 8.35 | 1.84 | 0.16 | 12.55 | 20.66 | 78.26 | 17.24 | 1.65 | 117.81 | 10.67 |
7 | 1 | 1 | −1 | 99.7 | 72.8 | 20.3 | 5.19 | 12.50 | 2.62 | 0.26 | 20.57 | 27.91 | 66.37 | 13.56 | 1.37 | 109.20 | 18.83 |
8 | 1 | 1 | 1 | 99.7 | 72.8 | 79.7 | 3.55 | 12.22 | 2.59 | 0.24 | 18.61 | 25.30 | 91.16 | 19.30 | 1.78 | 137.55 | 13.67 |
9 | 1.68 | 0 | 0 | 120 | 55 | 50 | 4.87 | 12.55 | 2.64 | 0.26 | 20.33 | 29.51 | 73.64 | 14.24 | 1.48 | 118.87 | 17.80 |
10 | −1.68 | 0 | 0 | 20 | 55 | 50 | 4.23 | 11.17 | 2.38 | 0.25 | 18.02 | 28.03 | 72.34 | 14.50 | 1.59 | 116.46 | 14.59 |
11 | 0 | −1.68 | 0 | 70 | 25 | 50 | 3.46 | 8.81 | 1.79 | 0.16 | 14.22 | 27.38 | 68.68 | 13.51 | 1.25 | 110.82 | 12.63 |
12 | 0 | 1.68 | 0 | 70 | 85 | 50 | 5.04 | 13.22 | 2.91 | 0.25 | 21.42 | 27.23 | 73.01 | 14.94 | 1.37 | 116.55 | 18.49 |
13 | 0 | 0 | −1.68 | 70 | 55 | 0 | 4.58 | 11.38 | 2.32 | 0.23 | 18.51 | 26.95 | 67.10 | 13.74 | 1.36 | 109.15 | 16.99 |
14 | 0 | 0 | 1.68 | 70 | 55 | 100 | 0.66 | 6.59 | 1.51 | 0.13 | 8.89 | 11.37 | 106.03 | 24.85 | 2.06 | 144.31 | 5.83 |
15 | −1.68 | −1.68 | −1.68 | 20 | 25 | 0 | 2.86 | 7.13 | 1.42 | 0.14 | 11.54 | 28.68 | 69.86 | 14.28 | 1.33 | 114.15 | 9.96 |
16 | −1.68 | −1.68 | 1.68 | 20 | 25 | 100 | 0.26 | 1.78 | 0.52 | 0.04 | 2.60 | 9.04 | 62.59 | 18.30 | 1.35 | 91.28 | 2.89 |
17 | −1.68 | 1.68 | −1.68 | 20 | 85 | 0 | 5.09 | 12.43 | 2.46 | 0.23 | 20.21 | 27.84 | 68.06 | 13.44 | 1.26 | 110.60 | 18.28 |
18 | −1.68 | 1.68 | 1.68 | 20 | 85 | 100 | 0.99 | 9.08 | 2.00 | 0.16 | 12.23 | 13.93 | 127.65 | 28.10 | 2.29 | 171.97 | 7.11 |
19 | 1.68 | −1.68 | −1.68 | 120 | 25 | 0 | 2.87 | 7.99 | 1.74 | 0.15 | 12.75 | 28.76 | 80.72 | 17.06 | 1.54 | 128.08 | 11.01 |
20 | 1.68 | −1.68 | 1.68 | 120 | 25 | 100 | 0.32 | 2.57 | 0.67 | 0.05 | 3.61 | 10.97 | 88.03 | 23.02 | 1.72 | 123.74 | 2.93 |
21 | 1.68 | 1.68 | −1.68 | 120 | 85 | 0 | 4.88 | 11.91 | 2.54 | 0.22 | 19.55 | 27.42 | 65.49 | 14.95 | 1.30 | 109.16 | 17.22 |
22 | 1.68 | 1.68 | 1.68 | 120 | 85 | 100 | 1.28 | 10.44 | 2.35 | 0.18 | 14.26 | 16.21 | 130.81 | 28.85 | 2.26 | 178.12 | 8.30 |
23 | 0 | 0 | 0 | 70 | 55 | 50 | 5.02 | 12.73 | 2.60 | 0.25 | 20.61 | 26.54 | 68.09 | 13.12 | 1.35 | 109.09 | 18.72 |
24 | 0 | 0 | 0 | 70 | 55 | 50 | 4.66 | 12.03 | 2.36 | 0.23 | 19.28 | 27.53 | 70.12 | 15.04 | 1.39 | 114.08 | 17.17 |
25 | 0 | 0 | 0 | 70 | 55 | 50 | 4.92 | 12.59 | 2.65 | 0.26 | 20.42 | 27.79 | 70.03 | 14.23 | 1.39 | 113.44 | 17.97 |
26 | 0 | 0 | 0 | 70 | 55 | 50 | 4.94 | 12.58 | 2.55 | 0.25 | 20.32 | 24.84 | 65.56 | 13.31 | 1.28 | 104.99 | 19.31 |
27 | 0 | 0 | 0 | 70 | 55 | 50 | 5.11 | 12.95 | 2.62 | 0.25 | 20.92 | 27.81 | 70.57 | 14.98 | 1.38 | 114.74 | 18.35 |
28 | 0 | 0 | 0 | 70 | 55 | 50 | 4.92 | 12.30 | 2.44 | 0.24 | 19.90 | 27.51 | 68.82 | 14.28 | 1.34 | 111.96 | 17.88 |
ANOVA Estimated Coefficients | ||||||||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Term | Y1 | Y2 | Y3 | Y4 | Y5 | Y6 | Y7 | Y8 | Y9 | Y10 | Y11 | |||||||||
Intercept | 4.75 | 12.28 | 2.53 | 19.81 | 19.56 | 27.29 | 69.50 | 14.02 | 1.40 | 112.22 | 17.56 | |||||||||
A-time | −0.02 | 0.08 | 0.04 | 0.10 | 0.09 | 0.20 | 1.90 | 0.57 | 0.04 | 2.70 | −0.10 | |||||||||
B-Temp | 0.47 | 1.71 | 0.35 | 2.57 | 2.53 | 0.61 | 5.21 | 0.78 | 0.07 | 6.67 | 1.70 | |||||||||
C-Solvent | −0.99 | −1.11 | −0.18 | −2.30 | −2.28 | −4.22 | 9.38 | 2.71 | 0.17 | 8.04 | −2.63 | |||||||||
AB | 0.01 | −0.03 | 0.00 | −0.02 | −0.02 | −0.01 | −1.54 | −0.26 | −0.02 | −1.83 | 0.03 | |||||||||
AC | 0.03 | 0.11 | 0.01 | 0.15 | 0.15 | 0.19 | 0.83 | 0.06 | 0.00 | 1.09 | 0.06 | |||||||||
BC | −0.10 | 0.27 | 0.06 | 0.23 | 0.23 | 0.59 | 5.24 | 0.80 | 0.07 | 6.70 | −0.20 | |||||||||
A2 | −0.03 | −0.09 | −0.01 | −0.12 | −0.13 | 0.50 | 0.70 | 0.10 | 0.04 | 1.35 | −0.32 | Not significant | Significant | |||||||
B2 | −0.14 | −0.39 | −0.06 | −0.60 | −0.59 | −0.02 | −0.06 | 0.05 | −0.04 | −0.07 | −0.54 | |||||||||
C2 | −0.72 | −1.11 | −0.22 | −2.06 | −2.04 | −2.90 | 5.51 | 1.85 | 0.10 | 4.56 | −2.01 | |||||||||
R2 | 0.98 | 0.97 | 0.97 | 0.98 | 0.98 | 0.96 | 0.96 | 0.97 | 0.95 | 0.94 | 0.96 | |||||||||
Lack of fit | 0.10 | 0.06 | 0.38 | 0.49 | 0.09 | 0.25 | 0.02 | 0.35 | 0.08 | 0.14 | 0.12 | |||||||||
Decoded Optimization | ||||||||||||||||||||
Factor | Y1 | Y2 | Y3 | Y4 | Y5 | Y6 | Y7 | Y8 | Y9 | Y10 | Y11 | Global | ||||||||
Time (min) | 53 | 68 | 120 | 120 | 68 | 120 | 120 | 120 | 120 | 120 | 66 | 120 | ||||||||
Temperature (°C) | 84.94 | 84.94 | 84.94 | 72.55 | 84.94 | 81.19 | 84.94 | 84.94 | 84.87 | 84.87 | 84.94 | 84.94 | ||||||||
Solvent (%) | 26 | 41 | 45 | 40 | 36 | 35 | 100 | 100 | 100 | 100 | 28 | 76 | −1.6 | 0 | 1.6 | |||||
Single Opt Value | 5.63 | 14.16 | 2.99 | 0.28 | 22.86 | 30.65 | 127.46 | 28.23 | 2.27 | 174.86 | 20 | |||||||||
Global Opt Value (mg/g dry weight or mg/g extract) | 3.50 ± 0.43 | 12.55 ± 0.99 | 2.75 ± 0.21 | 0.24 ± 0.02 | 19.04 ± 1.50 | 25.09 ± 2.45 | 100.77 ± 7.19 | 21.19 ± 1.61 | 1.83 ± 0.12 | 148.88 ± 8.73 | 13.70 ± 1.90 | |||||||||
Desirability | 0.64 | 0.88 | 0.92 | 0.89 | 0.83 | 0.78 | 0.57 | 0.53 | 0.60 | 0.66 | 0.66 | 0.71 |
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Madureira, J.; Melgar, B.; Santos-Buelga, C.; Margaça, F.M.A.; Ferreira, I.C.F.R.; Barros, L.; Cabo Verde, S. Phenolic Compounds from Irradiated Olive Wastes: Optimization of the Heat-Assisted Extraction Using Response Surface Methodology. Chemosensors 2021, 9, 231. https://doi.org/10.3390/chemosensors9080231
Madureira J, Melgar B, Santos-Buelga C, Margaça FMA, Ferreira ICFR, Barros L, Cabo Verde S. Phenolic Compounds from Irradiated Olive Wastes: Optimization of the Heat-Assisted Extraction Using Response Surface Methodology. Chemosensors. 2021; 9(8):231. https://doi.org/10.3390/chemosensors9080231
Chicago/Turabian StyleMadureira, Joana, Bruno Melgar, Celestino Santos-Buelga, Fernanda M. A. Margaça, Isabel C. F. R. Ferreira, Lillian Barros, and Sandra Cabo Verde. 2021. "Phenolic Compounds from Irradiated Olive Wastes: Optimization of the Heat-Assisted Extraction Using Response Surface Methodology" Chemosensors 9, no. 8: 231. https://doi.org/10.3390/chemosensors9080231
APA StyleMadureira, J., Melgar, B., Santos-Buelga, C., Margaça, F. M. A., Ferreira, I. C. F. R., Barros, L., & Cabo Verde, S. (2021). Phenolic Compounds from Irradiated Olive Wastes: Optimization of the Heat-Assisted Extraction Using Response Surface Methodology. Chemosensors, 9(8), 231. https://doi.org/10.3390/chemosensors9080231