Abstract

The increasing emphasis on the development of green replacements to traditional organic solvents and ionic liquids
(ILs) can be attributed to the rising concerns over human health and detrimental impacts of conventional solvents towards the environment. A new generation of solvents inspired by nature and extracted from plant bioresources has
evolved over the last few years, and are referred to as natural deep eutectic solvents (NADES). NADES are mixtures
of natural constituents like sugars, polyalcohols, sugar-based alcohols, amino acids and organic acids. Interest in
NADES has exponentially grown over the last eight years, which is evident from an upsurge in the number of research
projects undertaken. NADES are highly biocompatible as they can be biosynthesized and metabolized by nearly all living organisms. These solvents pose several noteworthy advantages, such as easy synthesis, tuneable physico-chemical
properties, low toxicity, high biodegradability, solute sustainability and stabilization and low melting point. Research
on the applicability of NADES in diverse areas is gaining momentum, which includes as - media for chemical and enzymatic reactions; extraction media for essential oils; anti-inflammatory and antimicrobial agent; extraction of bioactive composites; as chromatographic media; preservatives for labile compounds and in drug synthesis. This review
gives a complete overview of the properties, biodegradability and toxicity of NADES which we propose can assist in
further knowledge generation on their significance in biological systems and usage in green and sustainable chemistry.
Information on applications of NADES in biomedical, therapeutic and pharma-biotechnology fields is also highlighted
in the current article along with the recent progress and future perspectives in novel applications of NADES.