Optimization of Microwave-Assisted Extraction of Polyphenols from Lemon Myrtle: Comparison of Modern and Conventional Extraction Techniques Based on Bioactivity and Total Polyphenols in Dry Extracts
Abstract
:1. Introduction
2. Materials and Methods
2.1. Plant Materials
2.2. Chemical and Reagents
2.3. Experimental Design
2.3.1. Optimization of MAE Conditions Using Response Surface Methodology (RSM)
2.3.2. Ultrasound-Assisted Extraction (UAE)
2.3.3. Conventional Extraction Using Shaking Water Bath Extraction (SWB)
2.4. UV Spectrophotometric Measurement of Total Phenolics (TPC), Flavonoids (TFC), and Proanthocyanidins (Pro. A)
2.5. Measurement of Antioxidant Properties
2.6. Total Chlorophyll Content
2.7. Antimicrobial Activity Assay
2.7.1. Bacterial Culture and Preparation of Inoculum
2.7.2. Disc Diffusion Bioassay
2.8. Statistical Analysis
3. Result and Discussion
3.1. Investigation of MAE Influencing Factors and Optimisation of MAE Conditions
3.1.1. Accuracy of the Polynomial Prediction Models
3.1.2. Influence of MAE Parameters on Polyphenols and Antioxidant Properties Yield
3.1.3. Optimization and Validation
3.2. Comparison of the Effects of Conventional and Novel Extraction Techniques on Phenolics, Chlorophyll, Antioxidants, and Antimicrobial Properties
4. Conclusions
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Acknowledgments
Conflicts of Interest
References
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Run | Experimental Conditions (Independent Variables) | Observed Responses (Dependent Variables) (n = 3) | |||||||||
---|---|---|---|---|---|---|---|---|---|---|---|
Pattern | X1 | X2 | X3 | Phytochemicals | Antioxidant Capacity | ||||||
TPC | TFC | Pro. A | FRAP | CUPRAC | DPPH | ABTS | |||||
1 | +−0 | 6 | 10 | 5 | 93.67247 | 88.02825 | 104.0927 | 683.4416 | 5827.626 | 985.7716 | 1371.562 |
2 | −0+ | 2 | 55 | 8 | 89.31072 | 85.19821 | 92.55855 | 737.6218 | 5723.661 | 991.6801 | 1296.063 |
3 | 000 | 4 | 55 | 5 | 94.77291 | 86.74644 | 99.4709 | 695.8874 | 5338.929 | 997.0779 | 1322.186 |
4 | 0++ | 4 | 100 | 8 | 96.58725 | 91.91176 | 103.6901 | 793.6621 | 6163.616 | 1007.508 | 1407.265 |
5 | −+0 | 2 | 100 | 5 | 85.43417 | 77.76763 | 87.44164 | 621.3235 | 5105.042 | 839.3812 | 1221.161 |
6 | −−0 | 2 | 10 | 5 | 69.86795 | 62.6842 | 74.89885 | 484.4347 | 4070.798 | 718.2009 | 990.0688 |
7 | ++0 | 6 | 100 | 5 | 105.8023 | 95.40555 | 111.5702 | 811.5801 | 6260.000 | 1155.195 | 1549.675 |
8 | 0−+ | 4 | 10 | 8 | 71.02841 | 70.43143 | 87.62903 | 599.0081 | 4384.782 | 777.6093 | 1087.066 |
9 | 000 | 4 | 55 | 5 | 95.1325 | 92.49178 | 103.0034 | 730.4654 | 5451.429 | 951.2987 | 1561.580 |
10 | 0−− | 4 | 10 | 2 | 67.76044 | 71.67215 | 91.63295 | 436.1154 | 3884.874 | 703.0176 | 1239.114 |
11 | 0+− | 4 | 100 | 2 | 82.07033 | 91.03641 | 107.7913 | 493.9362 | 4659.139 | 789.9637 | 1520.961 |
12 | −0− | 2 | 55 | 2 | 62.37495 | 68.82536 | 92.46291 | 370.5118 | 3378.939 | 471.9729 | 1216.816 |
13 | +0− | 6 | 55 | 2 | 86.92227 | 94.55304 | 115.2998 | 561.0199 | 4783.613 | 796.4094 | 1609.769 |
14 | 000 | 4 | 55 | 5 | 92.35194 | 89.33138 | 102.3861 | 772.8705 | 5309.874 | 927.3300 | 1505.634 |
15 | +0+ | 6 | 55 | 8 | 100.2345 | 97.62057 | 103.7533 | 854.7754 | 5900.446 | 945.2110 | 1548.363 |
Model Parameters | Phytochemicals | Antioxidant Capacity Measures | |||||
---|---|---|---|---|---|---|---|
TPC | TFC | Pro. A | FRAP | CUPRAC | DPPH | ABTS | |
Intercept β0 | 94.08 *** | 89.52 *** | 101.62 *** | 733.07 *** | 5366.74 *** | 958.67 *** | 1463.13 *** |
Linear term | |||||||
β1 | 9.96 *** | 10.14 ** | 10.92 *** | 87.12 ** | 561.66 ** | 107.67 * | 169.41 ** |
β2 | 8.45 ** | 7.91 ** | 6.53 ** | 64.68 ** | 502.46 * | 75.93 * | 126.41 * |
β3 | 7.25 ** | 2.38 | −2.44 | 140.44 *** | 683.24 ** | 120.08 ** | −30.99 |
Interactions | |||||||
β12 | −0.86 | −1.93 | −1.27 | −2.19 | −150.47 | 12.06 | −13.24 |
β13 | −3.41 | −3.33 | −2.91 | −18.34 | −306.97 | −92.73 | −35.16 |
β23 | 2.81 | 0.53 | −0.02 | 34.21 | 251.14 | 35.74 | 9.59 |
Quadratic | |||||||
β11 | −0.02 | −1.63 | −1.89 | −16.29 | 61.34 | −26.07 | −37.93 |
β22 | −5.37 | −6.9190 * | −5.23 * | −66.59 * | −112.22 | −7.86 | −142.08 |
β33 | −9.35 ** | −1.34 | 1.29 | −85.81 * | −481.42 * | −131.1815 * | −7.45 |
Model fitting indicators | |||||||
R2 | 0.96 | 0.94 | 0.95 | 0.97 | 0.94 | 0.92 | 0.91 |
Adjusted R2 | 0.89 | 0.82 | 0.87 | 0.92 | 0.83 | 0.77 | 0.74 |
RMSE | 4.337 | 4.7065 | 3.8377 | 41.805 | 359.27 | 79.956 | 96.53 |
Lack of fit | 0.0709 | 0.2157 | 0.1415 | 0.4642 | 0.0259 | 0.116 | 0.8132 |
F ratio of model | 13.2033 | 8.0893 | 11.34 | 18.99 | 8.53 | 6.24 | 5.34 |
P of model > F | 0.006 | 0.017 | 0.0078 | 0.0024 | 0.0147 | 0.0289 | 0.0397 |
Values (n = 3) | ||
---|---|---|
Predicted | Experimental | |
TPC (mg GAE/g DW) | 106.51 ± 7.32 a | 108.06 ± 3.73 a |
TFC (mg CE/g DW) | 98.85 ± 7.88 a | 101.41 ± 3.82 a |
Proanthocyanidins (mg CE/g DW) | 110.18 ± 6.43 a | 114.23 ± 2.39 a |
FRAP (mM TE/g DW) | 852.30 ± 70.03 a | 947.15 ± 36.37 a |
CUPRAC (mMTE/g DW) | 6194.44 ± 601.82 a | 6395.53 ± 157.82 a |
DPPH (mMTE/g DW) | 1067.14 ± 133.93 a | 1188.311 ± 39.17 a |
ABTS (mMTE/g DW) | 1594.73 ± 161.7 a | 1797.17 ± 91.20 a |
MAE | UAE | SWB | |
---|---|---|---|
Phenolic compounds | |||
TPC (mg GAE/g DW) | 406.67 ± 8.57 a | 399.03 ± 7.65 a | 398.10 ± 2.76 a |
TFC (mg CE/g DW) | 384.57 ± 2.74 a | 381.57 ± 5.29 a | 379.13 ± 7.77 a |
Pro. A (mg CE/g DW) | 336.54 ± 7.09 a | 347.58 ± 6.85 a | 347.39 ± 5.76 a |
Antioxidant capacities | |||
FRAP (mM TE/g DW) | 3175.56 ± 79.39 a | 3221.73 ± 158.54 a | 3272.45 ± 101.46 a |
CUPRAC (mM TE/g DW) | 22,479.77 ± 87.89 c | 23,270.17 ± 146.33 b | 24,520.28 ± 154.34 a |
ABTS (mM TE/g DW) | 7023.99 ± 83.49 b | 7040.03 ± 103.22 b | 7241.42 ± 38.75 a |
DPPH (mM TE/g DW) | 4531.04 ± 33.02 ab | 4404.50 ± 53.14 b | 4645.36 ± 72.92 a |
Total chlorophyll content mg/g dry extract | 1.14 ± 0.49 b | 1.29 ± 0.09 a | 1.33 ± 0.05 a |
Bacteria | Inhibition Zone (mm) (n = 9) | ||||||
---|---|---|---|---|---|---|---|
MAE | UAE | SWB | Ciprofloxacin (5 µg/disc) | ||||
15 mg/mL | 20 mg/mL | 15 mg/mL | 20 mg/mL | 15 mg/mL | 20 mg/mL | ||
E. coli | ND | ND | ND | ND | ND | ND | |
E. aerogenes | ND | ND | ND | ND | ND | ND | |
S. lugdunensis | 9.42 ± 0.49 b | 10.42 ± 0.38 b | 9.25 ± 0.61 b | 10.58 ± 0.38 b | 8.83 ± 0.81 b | 10.17 ± 0.26 b | 34.92 ± 0.20 a |
B. cereus | 8.58 ± 0.38 b | 9.33 ± 0.26 b | 8.75 ± 0.61 b | 9.33 ± 0.26 b | 8.67 ± 0.26 b | 9.83 ± 0.26 b | 26.08 ± 0.66 a |
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Saifullah, M.; McCullum, R.; Vuong, Q.V. Optimization of Microwave-Assisted Extraction of Polyphenols from Lemon Myrtle: Comparison of Modern and Conventional Extraction Techniques Based on Bioactivity and Total Polyphenols in Dry Extracts. Processes 2021, 9, 2212. https://doi.org/10.3390/pr9122212
Saifullah M, McCullum R, Vuong QV. Optimization of Microwave-Assisted Extraction of Polyphenols from Lemon Myrtle: Comparison of Modern and Conventional Extraction Techniques Based on Bioactivity and Total Polyphenols in Dry Extracts. Processes. 2021; 9(12):2212. https://doi.org/10.3390/pr9122212
Chicago/Turabian StyleSaifullah, Md, Rebecca McCullum, and Quan Van Vuong. 2021. "Optimization of Microwave-Assisted Extraction of Polyphenols from Lemon Myrtle: Comparison of Modern and Conventional Extraction Techniques Based on Bioactivity and Total Polyphenols in Dry Extracts" Processes 9, no. 12: 2212. https://doi.org/10.3390/pr9122212
APA StyleSaifullah, M., McCullum, R., & Vuong, Q. V. (2021). Optimization of Microwave-Assisted Extraction of Polyphenols from Lemon Myrtle: Comparison of Modern and Conventional Extraction Techniques Based on Bioactivity and Total Polyphenols in Dry Extracts. Processes, 9(12), 2212. https://doi.org/10.3390/pr9122212