13C CPMAS NMR as an Alternative Method to Verify the Quality of Dietary Supplements Containing Curcumin
Abstract
:1. Introduction
2. Results and Discussion
3. Materials and Methods
Supplementary Materials
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Acknowledgments
Conflicts of Interest
Sample Availability
References
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Ethanol | Acetonitrile | Isopropanol | |
---|---|---|---|
Solubility (g/L) | |||
Curcumin | 3.9 | 7.2 | 0.91 |
Demethoxycurcumin | 45 | 26 | 16.2 |
Bisdemethoxycurcumin | 53 | 11 | 8.2 |
Functional | a (Å) | b (Å) | c (Å) | α (°) | β (°) | γ (°) | Volume (Å3) |
---|---|---|---|---|---|---|---|
GGA PBESOL | 12.375 | 7.567 | 20.771 | 90 | 90.510 | 90 | 1945.03 |
LDA CA-PZ | 12.178 | 6.765 | 19.572 | 90 | 94.745 | 90 | 1607.00 |
LDA CA-PZ OBS | 11.970 | 5.975 | 18.671 | 90 | 96.386 | 90 | 1327.06 |
GGA PBE | 12.838 | 8.394 | 21.171 | 90 | 89.149 | 90 | 2281.16 |
GGA PBE TS | 12.625 | 6.983 | 19.985 | 90 | 94.826 | 90 | 1755.64 |
GGA PBE Grimme | 12.533 | 6.824 | 19.891 | 90 | 95.137 | 90 | 1694.48 |
GGA RPBE | 13.479 | 9.988 | 22.124 | 90 | 86.774 | 90 | 2973.81 |
GGA PW91 | 13.001 | 8.631 | 21.321 | 90 | 88.326 | 90 | 2391.67 |
GGA PW91 OBS | 12.273 | 6.523 | 19.207 | 90 | 96.289 | 90 | 1528.42 |
GGA WC | 12.433 | 9.070 | 21.419 | 90 | 86.695 | 90 | 2411.54 |
C Atom Number | Experiment | Polymorph I | Polymorph II | Polymorph II * | Polymorph III |
---|---|---|---|---|---|
1 | 98.6 | 97.9 | 105.3 | 107.5 | 105.6 |
2 | 186.8 | 181.0 | 183.0 | 180.1 | 180.3 |
2’ | 182.4 | 174.4 | 171.8 | 172.9 | 171.9 |
3 | 122.8 | 122.5 | 120.1 | 119.6 | 121.0 |
3’ | 122.8 | 118.9 | 118.4 | 118.0 | 114.9 |
4 | 140.2 | 139.9 | 137.9 | 138.9 | 138.0 |
4’ | 140.2 | 138.7 | 135.2 | 136.5 | 138.1 |
5 | 128.8 | 126.3 | 125.1 | 122.7 | 121.6 |
5’ | 129.7 | 125.7 | 125.9 | 124.6 | 124.5 |
6 | 124.8 | 122.7 | 113.0 | 114.5 | 114.3 |
6’ | 124.8 | 120.1 | 112.7 | 114.5 | 113.1 |
7 | 114.1 | 109.2 | 110.0 | 112.0 | 114.4 |
7’ | 114.9 | 112.1 | 111.9 | 111.5 | 109.6 |
8 | 148.1 | 151.3 | 146.3 | 148.9 | 147.7 |
8’ | 148.1 | 149.5 | 145.1 | 146.8 | 147.4 |
9 | 148.1 | 145.7 | 144.2 | 145.8 | 145.7 |
9’ | 148.1 | 147.0 | 144.6 | 144.4 | 144.8 |
10 | 108.2 | 104.8 | 109.5 | 114.4 | 113.5 |
10’ | 109.8 | 112.1 | 111.9 | 111.5 | 109.6 |
11 | 54.9 | 49.8 | 51.0 | 52.2 | 51.4 |
11’ | 56.8 | 52.3 | 49.7 | 54.1 | 52.6 |
MAE | 3.25 | 4.83 | 4.66 | 4.68 |
C Atom Number | δEXP-δCALC I | δEXP-δCALC II | δEXP-δCALC II * | δEXP-δCALC III |
---|---|---|---|---|
1 | 0.7 | −6.7 | −8.9 | −7 |
2 | 5.8 | 3.8 | 6.7 | 6.5 |
2’ | 8 | 10.6 | 9.5 | 10.5 |
3 | 0.3 | 2.7 | 3.2 | 1.8 |
3’ | 3.9 | 4.4 | 4.8 | 7.9 |
4 | 0.3 | 2.3 | 1.3 | 2.2 |
4’ | 1.5 | 5 | 3.7 | 2.1 |
5 | 2.5 | 3.7 | 6.1 | 7.2 |
5’ | 4 | 3.8 | 5.1 | 5.2 |
6 | 2.1 | 11.8 | 10.3 | 10.5 |
6’ | 4.7 | 12.1 | 10.3 | 11.7 |
7 | 4.9 | 4.1 | 2.1 | −0.3 |
7’ | 2.8 | 3 | 3.4 | 5.3 |
8 | −3.2 | 1.8 | −0.8 | 0.4 |
8’ | −1.4 | 3 | 1.3 | 0.7 |
9 | 2.4 | 3.9 | 2.3 | 2.4 |
9’ | 1.1 | 3.5 | 3.7 | 3.3 |
10 | 3.4 | −1.3 | −6.2 | −5.3 |
10’ | −2.3 | −2.1 | −1.7 | 0.2 |
11 | 5.1 | 3.9 | 2.7 | 3.5 |
11’ | 4.5 | 7.1 | 2.7 | 4.2 |
No. | Form | Declared Content |
---|---|---|
S1 | Capsule | 250 mg turmeric rhizome extract (curcumin min. 70%); 2.5 mg black pepper extract (piperine 95%) |
S2 | Capsule | 350 mg turmeric rhizome extract (266 mg curcumin); 5 mg black pepper extract (4.75 mg piperine) |
S3 | Capsule | 332 mg curcumin (95%) |
S4 | Tablet | 300 mg curcumin (95%); 5 mg piperine (95%) |
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Siudem, P.; Szeleszczuk, Ł.; Zielińska, A.; Paradowska, K. 13C CPMAS NMR as an Alternative Method to Verify the Quality of Dietary Supplements Containing Curcumin. Molecules 2023, 28, 3442. https://doi.org/10.3390/molecules28083442
Siudem P, Szeleszczuk Ł, Zielińska A, Paradowska K. 13C CPMAS NMR as an Alternative Method to Verify the Quality of Dietary Supplements Containing Curcumin. Molecules. 2023; 28(8):3442. https://doi.org/10.3390/molecules28083442
Chicago/Turabian StyleSiudem, Paweł, Łukasz Szeleszczuk, Agnieszka Zielińska, and Katarzyna Paradowska. 2023. "13C CPMAS NMR as an Alternative Method to Verify the Quality of Dietary Supplements Containing Curcumin" Molecules 28, no. 8: 3442. https://doi.org/10.3390/molecules28083442