Impact of Conventional and Sustainable Solvents on the Yield, Selectivity, and Recovery of Curcuminoids from Turmeric

Carotenoids—natural fat-soluble pigments—have attracted considerable attention because of their potential to prevent of various diseases, such as cancer and arteriosclerosis, and their strong antioxidant capacity. They have many geometric isomers due to the presence of numerous conjugated double bonds in the molecule. However, in plants, most carotenoids are present in the all-E-configuration. (all-E)-Carotenoids are characterized by high crystallinity as well as low solubility in safe and sustainable solvents, such as ethanol and supercritical CO2 (SC-CO2). Thus, these properties result in the decreased efficiency of carotenoid processing, such as extraction and emulsification, using such sustainable solvents. On the other hand, Z-isomerization of carotenoids induces alteration in physicochemical properties, i.e., the solubility of carotenoids dramatically improves and they change from a “crystalline state” to an “oily (amorphous) state”. For example, the solubility in ethanol of lycopene Z-isomers is more than 4000 times higher than the all-E-isomer. Recently, improvement of carotenoid processing efficiency utilizing these changes has attracted attention. Namely, it is possible to markedly improve carotenoid processing using safe and sustainable solvents, which had previously been difficult to put into practical use due to the low efficiency. The objective of this paper is to review the effect of Z-isomerization on the physicochemical properties of carotenoids and its application to carotenoid processing, such as extraction, micronization, and emulsification, using sustainable solvents. Moreover, aspects of Z-isomerization methods for carotenoids and functional difference, such as bioavailability and antioxidant capacity, between isomers are also included in this review.

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Recent Progress of Cu-Catalyzed Azide-Alkyne Cycloaddition Reactions (CuAAC) in Sustainable Solvents: Glycerol, Deep Eutectic Solvents, and Aqueous Media

Molecules ◽

10.3390/molecules25092015 ◽

2020 ◽

Vol 25 (9) ◽

pp. 2015 ◽

Cited By ~ 1

Author(s):

Noel Nebra ◽

Joaquín García-Álvarez

Keyword(s):

Recent Progress ◽

Copper Catalyst ◽

Aqueous Media ◽

Deep Eutectic Solvents ◽

Dipolar Cycloaddition ◽

Green Solvents ◽

Sustainable Solvents ◽

Volatile Organic ◽

Water Glycerol ◽

Reaction Media

This mini-review presents a general overview of the progress achieved during the last decade on the amalgamation of CuAAC processes (copper-catalyzed azide-alkyne cycloaddition) with the employment of sustainable solvents as reaction media. In most of the presented examples, the use of water, glycerol (Gly), or deep eutectic solvents (DESs) as non-conventional reaction media allowed not only to recycle the catalytic system (thus reducing the amount of the copper catalyst needed per mole of substrate), but also to achieve higher conversions and selectivities when compared with the reaction promoted in hazardous and volatile organic solvents (VOCs). Moreover, the use of the aforementioned green solvents also permits the improvement of the overall sustainability of the Cu-catalyzed 1,3-dipolar cycloaddition process, thus fulfilling several important principles of green chemistry.

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SUSSOL—Using Artificial Intelligence for Greener Solvent Selection and Substitution

Molecules ◽

10.3390/molecules25133037 ◽

2020 ◽

Vol 25 (13) ◽

pp. 3037 ◽

Cited By ~ 3

Author(s):

Hannes Sels ◽

Herwig De Smet ◽

Jeroen Geuens

Keyword(s):

Neural Network ◽

Artificial Intelligence ◽

Physical Properties ◽

The Self ◽

Self Organizing Map ◽

Solvent Selection ◽

Sustainable Solvents ◽

Cluster A ◽

User Friendly ◽

Intuitive Sense

Solvents come in many shapes and types. Looking for solvents for a specific application can be hard, and looking for green alternatives for currently used nonbenign solvents can be even harder. We describe a new methodology for solvent selection and substitution, by applying Artificial Intelligence (AI) software to cluster a database of solvents based on their physical properties. The solvents are processed by a neural network, the Self-organizing Map of Kohonen, which results in a 2D map of clusters. The resulting clusters are validated both chemically and statistically and are presented in user-friendly visualizations by the SUSSOL (Sustainable Solvents Selection and Substitution Software) software. The software helps the user in exploring the solvent space and in generating and evaluating a list of possible alternatives for a specific solvent. The alternatives are ranked based on their safety, health, and environment scores. Cases are discussed to demonstrate the possibilities of our approach and to show that it can help in the search for more sustainable and greener solvents. The SUSSOL software makes intuitive sense and in most case studies, the software confirms the findings in literature, thus providing a sound platform for selecting the most sustainable solvent candidate.

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Ultrafast amidation of esters using lithium amides under aerobic ambient temperature conditions in sustainable solvents

Chemical Science ◽

10.1039/d0sc01349h ◽

2020 ◽

Vol 11 (25) ◽

pp. 6500-6509 ◽

Cited By ~ 4

Author(s):

Michael Fairley ◽

Leonie J. Bole ◽

Florian F. Mulks ◽

Laura Main ◽

Alan R. Kennedy ◽

...

Keyword(s):

Ambient Temperature ◽

Organometallic Chemistry ◽

Room Temperature ◽

Temperature Conditions ◽

Lithium Amides ◽

Sustainable Solvents

Using 2-methyl THF as solvent enables efficient and ultrafast amidation of esters by lithium amides at room temperature in air, edging closer towards reaching air- and moisture-compatible polar organometallic chemistry.

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