# Monoterpenoid-Based Deep Eutectic Solvents/Natural Deep Eutectic Solvents: A Review on Its Characteristics and Applications

## TL;DR

This paper reviews monoterpenoid-based green solvents and their potential for industrial extraction and other applications.

## Contribution

The paper highlights recent advancements and unexplored opportunities in monoterpenoid-based DES/NADES from 2020–2025.

## Key findings

- Monoterpenoid-based DES/NADES show promise for extracting bioactive compounds and natural pigments.
- Combining these solvents with green extraction methods improves their industrial applicability.
- Unexplored areas include their use with supercritical CO2 and thermophysical property studies.

## Abstract

The use of deep eutectic solvents (DES) and natural deep
eutectic
solvents (NADES) as green extraction solvents holds significant potential
for various industrial applications. This review aims to summarize
recent studies (2020–2025) on the use of sustainable solvents
such as DES and NADES based on monoterpenoids in extraction processes.
It also covers their production and other applications found in the
literature such as extraction of natural compounds from raw materials,
biorefinery, and the combination with supercritical carbon dioxide.
According to the literature data, the use of green solvents can be
improved through its combination with green extraction methods (ohmic
heating, ultrasound, microwave, and supercritical technology). DES
and NADES can be prepared in specific molar proportions with the aid
of energy sources (conventional heating, microwave reactor, and ultrasound).
DES/NADES composed of monoterpenoids show significant potential for
industrial applications, particularly in the extraction of bioactive
compounds, antioxidants, and natural pigments from food matrices.
These solvents also hold potential for innovation and application
across various sectors, including health, pharmacy, chemistry, environment,
petrochemicals, biorefinery, metallurgy, and supercritical technology.
Unexplored areas, such as the combination of monoterpenoid-based DES/NADES
with supercritical carbon dioxide, the study of their phase equilibrium,
and investigation of their thermophysical properties under varying
temperature and pressure conditions, present interesting opportunities
from a technological point of view.