Hydrophobic Natural Deep Eutectic Solvents for Extraction of Bioactive Compounds: Multiscale Characterization, Quantum Simulations, and Molecular Interaction Studies with Cry j 1 and Amb a 1 Allergens

What if the key to fighting allergies lies in a humble wood extract and a green solvent? This study reveals a natural deep eutectic solvent that can pull out compounds with remarkable allergy-modulating power.

Imagine a solvent that's not only green but also surprisingly effective at extracting bioactive compounds from wood—and even better, those compounds might help tame allergies. Researchers synthesized six hydrophobic natural deep eutectic solvents (NADESs) by pairing camphor, thymol, eugenol, and menthol in a 1:1 ratio. They characterized them using a suite of techniques, from FTIR and thermal analysis to quantum simulations and molecular dynamics, revealing strong hydrogen bonding in eugenol-based mixtures, especially menthol–eugenol.

Using ultrasonic-assisted extraction on Thujopsis dolabrata wood, they obtained essential oil yields ranging from 1.91% to 7.90% depending on the solvent. Gas chromatography–mass spectrometry identified 47 bioactive compounds, with a morphinan derivative as the most abundant (9.31–11.16%). This compound also showed the strongest binding to allergens Cry j 1 and Amb a 1, with binding affinities of −8.60 and −7.40 kcal/mol, respectively, and inhibition concentrations in the low micromolar range.

Molecular docking revealed that hydrophobic interactions and hydrogen bonding drive these protein–ligand interactions. The study underscores NADESs as sustainable, effective tools for extracting bioactive compounds with potential allergy-modulating effects—a promising step toward greener, smarter solutions.

Key Points

• Six NADESs synthesized from camphor, thymol, eugenol, menthol.
• Extraction yields 1.91–7.90% from Thujopsis dolabrata wood.
• Morphinan derivative shows strong allergen binding (Cry j 1, Amb a 1).