Microwave-Assisted Extraction and HPLC-UV-CD Determination of (S)-usnic Acid in Cladonia foliacea
Abstract
:1. Introduction
2. Results
2.1. Isolation and Characterization of the Main Metabolites Present in C. foliacea Extract
2.2. Microwave-Assisted Extraction (MAE) Protocol
3. Materials and Methods
3.1. Lichen Material
3.2. Chemicals
3.3. Instruments
3.4. Isolation and Identification of Main Metabolites
3.4.1. Isolation and Identification of Main Metabolites
3.4.2. HPLC-UV/PAD-CD and HPLC-UV/PAD-ESI/MS Analysis
3.4.3. Electronic Circular Dichroism
3.4.4. Computer-Assisted Conformational Analyses and ECD Calculations
3.4.5. Quantitative Determination of (−)-(S)-UA in the Extract
3.4.6. Experimental Design of the Extraction Procedure
3.5. Experimental Design Analysis and Extraction Efficiency Enhancement
4. Conclusions
Supplementary Materials
Author Contributions
Funding
Data Availability Statement
Acknowledgments
Conflicts of Interest
Sample Availability
References
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Exp# | Solvent | N° of Cycles × Minutes | T°C | Y1 Extraction Yield (%) | Y2 (−)-(S)-UA Yield 1 |
---|---|---|---|---|---|
1 | Acetone | 2 × 5 | 60 | 4.16 | 12.86 |
2 | Acetone | 3 × 5 | 60 | 3.40 | 12.88 |
3 | Acetone | 2 × 5 | 80 | 3.60 | 13.07 |
4 | Acetone | 3 × 5 | 80 | 3.31 | 11.73 |
5 | Ethyl Acetate | 2 × 5 | 60 | 3.93 | 12.49 |
6 | Ethyl Acetate | 3 × 5 | 60 | 2.76 | 10.28 |
7 | Ethyl Acetate | 2 × 5 | 80 | 2.50 | 13.04 |
8 | Ethyl Acetate | 3 × 5 | 80 | 1.70 | 11.64 |
9 | Ethanol | 2 × 5 | 60 | 6.63 | 12.78 |
10 | Ethanol | 3 × 5 | 60 | 5.84 | 11.54 |
11 | Ethanol | 2 × 5 | 80 | 6.73 | 13.51 |
12 | Ethanol | 3 × 5 | 80 | 7.29 | 12.79 |
13 * | Ethanol | 2 × 5 | 70 | 6.15 ± 0.01 | 13.2 ± 0.7 |
Predicted ** | Ethanol | 2 × 5 | 70 | 7 ± 2 | 13 ± 2 |
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Cavalloro, V.; Marrubini, G.; Stabile, R.; Rossi, D.; Linciano, P.; Gheza, G.; Assini, S.; Martino, E.; Collina, S. Microwave-Assisted Extraction and HPLC-UV-CD Determination of (S)-usnic Acid in Cladonia foliacea. Molecules 2021, 26, 455. https://doi.org/10.3390/molecules26020455
Cavalloro V, Marrubini G, Stabile R, Rossi D, Linciano P, Gheza G, Assini S, Martino E, Collina S. Microwave-Assisted Extraction and HPLC-UV-CD Determination of (S)-usnic Acid in Cladonia foliacea. Molecules. 2021; 26(2):455. https://doi.org/10.3390/molecules26020455
Chicago/Turabian StyleCavalloro, Valeria, Giorgio Marrubini, Rita Stabile, Daniela Rossi, Pasquale Linciano, Gabriele Gheza, Silvia Assini, Emanuela Martino, and Simona Collina. 2021. "Microwave-Assisted Extraction and HPLC-UV-CD Determination of (S)-usnic Acid in Cladonia foliacea" Molecules 26, no. 2: 455. https://doi.org/10.3390/molecules26020455