Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2025 Aug 23;30(17):3468.
doi: 10.3390/molecules30173468.

COSMO-RS Solubility Screening and Coumarin Extraction from Pterocaulon polystachyum with Deep Eutectic Solvents

Victor Hugo Rodrigues  1 , Arthur Cavassa  1 , Júlia Cardeal  1 , Nathalya Brazil  2 , Helder Teixeira  2 , Gilsane von Poser  2 , Rubem Mário Vargas  1 , Ana Rita Duarte  3 , Eduardo Cassel  1
Affiliations

COSMO-RS Solubility Screening and Coumarin Extraction from Pterocaulon polystachyum with Deep Eutectic Solvents

Victor Hugo Rodrigues et al. Molecules. .

Abstract

Deep eutectic solvents (DESs) have been studied to obtain extracts from medicinal plants, aiming for a more environmentally friendly process. Aligned with this initiative, the use of predictive thermodynamic models for screening the best solvent represents a theoretical action to reduce experimental time and cost. Therefore, this study aimed to perform and validate a relative solubility screening of 5-methoxy-6,7-methylenedioxycoumarin and prenyletin-methyl-ether at 313 K in choline chloride, menthol, and betaine-based DES, using the COSMO-RS model in COSMOThermX software. The density of DES was also predicted with a maximum error of 7.31% for this property. Ultrasound-assisted extraction (UAE) with DES at 313 K, 30 min, and a solid/liquid ratio of 1:20 (w/w) was performed to confirm the theoretical solubility results experimentally, as the extracts were analyzed through ultrafast liquid chromatography (UFLC) for coumarin content. For the results, the coumarin molecules presented intense peaks in the nonpolar region of their σ-profile, and the relative solubility screening indicated the DES Men/Lau (2:1), known for its hydrophobic nature and low polarity, as the best DES to solubilize these coumarins. Nevertheless, the UFLC results, and the complementary solubility screening of pigments, showed an interaction preference of this DES with chlorophylls instead of coumarins. This result was corroborated by spectrophotometric analysis of the extracts in UV-Vis, demonstrating that experimental validation is still mandatory in extraction processes and that predictive methodologies such as COSMO-RS should be used as guiding tools and analyzed in a greater context, considering the complexity of plant matrices in the beginning of simulations.

Keywords: coumarin; emerging solvents; predictive model; relative solubility.

PubMed Disclaimer

Conflict of interest statement

The authors declare no conflicts of interest.

Figures

Figure 1
Figure 1
Charge density surface and the generated σ-profiles of 5-methoxy-6,7-methylenedioxycoumarin and prenyletin-methyl-ether.
Figure 2
Figure 2
Absolute logarithmic activity coefficient at infinite dilution of 5-methoxy-6,7-methylenedioxycoumarin and prenyletin-methyl-ether in 8 different DESs at 40 °C. Equal capital letters (A–F) indicate a group result similarity above a 95% confidence level.
Figure 3
Figure 3
UFCL chromatogram profile of UAE DES 2 extract, highlighting peaks A (5-methoxy-6,7-methylenedioxycoumarin) and B (prenyletin-methyl-ether). Red arrows indicate the beginning and end of chromatographic peaks.
Figure 4
Figure 4
UV absorption spectra of peaks A (5-methoxy-6,7-methylenedioxycoumarin) and B (prenyletin-methyl-ether) of the DES 2 extract.
Figure 5
Figure 5
Charge density surface of chlorophylls a, b, and the σ-profiles generated.
Figure 6
Figure 6
Absolute logarithmic activity coefficient at infinite dilution of chlorophyll a, chlorophyll b, 5-methoxy-6,7-methylenedioxycoumarin, and prenyletin-methyl-ether in DES 2 and DES 8 at 40 °C.
See this image and copyright information in PMC

References

    1. Abdussalam-Mohammed W., Ali A.Q., Errayes A.O. Green Chemistry: Principles, Applications, and Disadvantages. Chem. Methodol. 2020;4:408–423. doi: 10.33945/sami/chemm.2020.4.4. - DOI
    1. Benvenutti L., Zielinski A.A.F., Ferreira S.R.S. Which Is the Best Food Emerging Solvent: IL, DES or NADES? Trends Food Sci. Technol. 2019;90:133–146. doi: 10.1016/j.tifs.2019.06.003. - DOI
    1. Abbott A.P., Boothby D., Capper G., Davies D.L., Rasheed R.K. Deep Eutectic Solvents Formed between Choline Chloride and Carboxylic Acids: Versatile Alternatives to Ionic Liquids. J. Am. Chem. Soc. 2004;126:9142–9147. doi: 10.1021/ja048266j. - DOI - PubMed
    1. Ivanović M., Islamčević Razboršek M., Kolar M. Innovative Extraction Techniques Using Deep Eutectic Solvents and Analytical Methods for the Isolation and Characterization of Natural Bioactive Compounds from Plant Material. Plants. 2020;9:1428. doi: 10.3390/plants9111428. - DOI - PMC - PubMed
    1. Martins M.A.R., Pinho S.P., Coutinho J.A.P. Insights into the Nature of Eutectic and Deep Eutectic Mixtures. J. Solution Chem. 2019;48:962–982. doi: 10.1007/s10953-018-0793-1. - DOI

MeSH terms

LinkOut - more resources