Potential of Deep Eutectic Solvents in the Extraction of Organic Compounds from Food Industry By-Products and Agro-Industrial Waste

Abstract

Global food waste has a huge impact on the environment, as it is a source of greenhouse gas emissions and wasted natural resources. Across the world, over 30% of food is lost or wasted each year. Aside from this, the food industry, as well, is one of the biggest sources of agro-industrial waste and by-products, which can be valorized and used for different purposes. Such waste is a good source of bioactive organic compounds that can be extracted without altering their properties, where deep eutectic solvents can serve as green solvents and as an excellent replacement for volatile organic solvents. Isolated compounds can be used in innovative food production, chemical production, cosmetics and other industries. Deep eutectic solvents have attracted extraordinary attention due to their advantages such as environmental friendliness, availability and easy preparation, easy handling and utilization of non-toxic components for their formation. Due to these properties, they are a greener alternative to classic organic solvents for many processes, including extractions. In this paper, we review the utilization of deep eutectic solvents as potential green media for the extraction of organic compounds such as polyphenols, carbohydrates, proteins and alkaloids from by-products of the food industry and from agro-industrial waste.

Avaliação De Modelo Didático Sobre a Herança Da Anemia Falciforme No Ensino De Genética

“…Regardless of the many advantages of DES, some recovery issues of the dissolved solutes after extraction have been reported such as solvent distillation but techniques are being explored: use of macroporous resins, solid phase extraction (SPE), antisolvent method and back extraction (Molnar et al, 2024), as shown in Figure 4, however, these methodologies still require the use of organic solvents such as ethanol and methanol (Palos-Hernández et al, 2022). However, the most recent techniques in protein extraction and purification involve the use of DES (Lin et al, 2022;Karimi et al, 2024); processes based on these solvents have reported higher extraction efficiencies up to 62-90% for plant proteins and aminoacids, higher results than other techniques, such as acid-based method (Li et al, 2021;Bowen et al, 2022;Zhou et al, 2022).…”

“…The term "eutectic" is derived from the greek word meaning low melting point and can be applied for different systems like alloys and also in liquid medium (Liu et al, 2018). In recent decades, DES have been used as unconventional solvents and they can be defined as "Mixtures of two or more pure compounds for which the eutectic point temperature is lower than that of an ideal liquid mixture, presenting significant negative deviations from ideality" and, due to their multiple properties, they have been used for the extraction of bioactive compounds, stabilization of biomolecules, enhancers of drug delivery, as well as, for the treatment of food industry waste (Molnar et al, 2024). The advantage of DES consists in their simple and inexpensive preparation, which involves only mixing and stirring at temperature below 150°C (Botelho Junior et al, 2022).…”

“…The only solvent that possesses these characteristics is water, however, it cannot be used for all types of extractions, since it does not dissolve hydrophobic compounds due to its high dielectric constant, hence the use of solvents that, at least decrease this environmental impact and are more biodegradable must follow some of the 12 principles of green chemistry (Ferreira & Sarraguça, 2024). It has been demonstrated that DES are more effective for protein extraction than classical organic solvents and, in addition the extraction efficiency is higher; DES have shown higher selectivity (Molnar et al, 2024). At industrial scale, the most commonly methods used for protein extraction involve organic solvents, as well as alkaline and acid solutions or enzyme-based extraction (Figure 3).…”

Combination of Natural Deep Eutectic Solvents and Nano-Liquid Chromatography towards White Analytical Chemistry: A Practical Application

“…In the field of analytical chemistry processes, other characteristics stand out, including a broad range of solubility, tunable properties through the adjustment of the components and their molar ratios, offering a customizable platform for specific applications, and great thermal stability. Thus, it has been widely demonstrated in several publications that they possess great potential as extraction agents [18][19][20][21]. Nevertheless, its high viscosity, although effective in avoiding processes such as oxidation or degradation of certain compounds, hinders its fluidic properties, handling, and mass transfer between sample and solvent.…”