A Comparative Analysis of Conventional and Deep Eutectic Solvent (DES)-Mediated Strategies for the Extraction of Chitin from Marine Crustacean Shells

Chitin, the second most abundant biopolymer on earth, is utilised in a wide range of applications including wastewater treatment, drug delivery, wound healing, tissue engineering, and stem cell technology among others. This review compares the most prevalent strategies for the extraction of chitin from crustacean sources including chemical methods that involve the use of harsh solvents and emerging methods using deep eutectic solvents (DES). In recent years, a significant amount of research has been carried out to identify and develop environmentally friendly processes which might facilitate the replacement of problematic chemicals utilised in conventional chemical extraction strategies with DES. This article provides an overview of different experimental parameters used in the DES-mediated extraction of chitin while also comparing the purity and yields of associated extracts with conventional methods. As part of this review, we compare the relative proportions of chitin and extraneous materials in different marine crustaceans. We show the importance of the species of crustacean shell in relation to chitin purity and discuss the significance of varying process parameters associated with different extraction strategies. The review also describes some recent applications associated with chitin. Following on from this review, we suggest recommendations for further investigation into chitin extraction, especially for experimental research pertaining to the enhancement of the “environmentally friendly” nature of the process. It is hoped that this article will provide researchers with a platform to better understand the benefits and limitations of DES-mediated extractions thereby further promoting knowledge in this area.

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Metal-Free 1,2,3-Triazole Synthesis in Deep Eutectic Solvents

Synlett ◽

10.1055/s-0039-1690736 ◽

2019 ◽

Vol 31 (06) ◽

pp. 605-609

Author(s):

Filip Sebest ◽

Samuel Haselgrove ◽

Andrew J. P. White ◽

Silvia Díez-González

Keyword(s):

Deep Eutectic Solvent ◽

Environmentally Friendly ◽

Deep Eutectic Solvents ◽

Metal Free ◽

Chromatographic Techniques

The metal-free regioselective preparation of 1,5- and 1,4-disubstituted triazoles is reported through a cycloaddition–elimination sequence. Reactions were carried out in environmentally friendly deep eutectic solvent (DES) and pure products were isolated without the need for chromatographic techniques.

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Natural Deep Eutectic Solvent-Assisted Pectin Extraction from Pomelo Peel Using Sonoreactor: Experimental Optimization Approach

Processes ◽

10.3390/pr7070416 ◽

2019 ◽

Vol 7 (7) ◽

pp. 416 ◽

Cited By ~ 6

Author(s):

Amal Elgharbawy ◽

Adeeb Hayyan ◽

Maan Hayyan ◽

Mohamed Mirghani ◽

Hamzah Salleh ◽

...

Keyword(s):

Choline Chloride ◽

Deep Eutectic Solvent ◽

Deep Eutectic Solvents ◽

Optimization Approach ◽

Degree Of Esterification ◽

Screening Design ◽

Natural Deep Eutectic Solvents ◽

Wide Range ◽

Definitive Screening ◽

Water Ratio

Background: Natural deep eutectic solvents (NADESs) can be used for extracting a wide range of biomaterials, such as pectin. This study introduces a new generation of natural solvents for pectin extraction which could replace the conventional solvents in the food industry. Methods: In this study, NADESs were used for pectin extraction from pomelo (Citrus grandis (L.) Osbeck) peels using a sonoreactor. Definitive screening design (DSD) was used to screen the influence of time, temperature, solid/liquid ratio, and NADES/water ratio on the pectin yield and degree of esterification (DE). Results: The primary screening revealed that the best choices for the extraction were choline chloride–malonic acid (ChCl-Mal) and choline chloride–glucose–water (ChCl:Glc:W). Both co-solvents yielded 94% pectin and 52% DE after optimization at 80 °C, with 60 min of sonication, pH < 3.0, and a NADES-to-water ratio of 1:4.5 (v/v). Morphological screening showed a smooth and compact surface of the pectin from ChCl-Mal where glucose-based pectin had a rough surface and lower DE. Conclusions: NADESs proved to be promising co-solvents for pectin extraction with a high degree of esterification (>55%).

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Metal- and solvent-free preparation of benzo[4,5]imidazo[1,2-a]pyrimidine derivatives catalysed by deep eutectic solvents

Vietnam Journal of Science Technology and Engineering ◽

10.31276/vjste.63(3).15-17 ◽

2021 ◽

Vol 63 (3) ◽

pp. 15-17

Author(s):

Thuy-Duy Thi Nguyen ◽

◽

Anh Vy Truong ◽

Hoang Phuong Tran ◽

◽

...

Keyword(s):

Ethyl Acetoacetate ◽

Good Yield ◽

Choline Chloride ◽

Biginelli Reaction ◽

Deep Eutectic Solvent ◽

Environmentally Friendly ◽

Deep Eutectic Solvents ◽

Solvent Free ◽

Pyrimidine Derivatives ◽

Solvent Free Conditions

by an acidic deep eutectic solvent from choline chloride (ChCl) and phenol via the Biginelli reaction of 2-aminobenzimidazole, ethyl acetoacetate, and aldehydes has been developed under metal- and solvent-free conditions. The desired products were obtained in moderate to good yield (49-79%) and the DESs were known as an economical and environmentally friendly catalyst.

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Green Valorization of Olive Leaves to Produce Polyphenol-Enriched Extracts Using an Environmentally Benign Deep Eutectic Solvent

AgriEngineering ◽

10.3390/agriengineering2020014 ◽

2020 ◽

Vol 2 (2) ◽

pp. 226-239 ◽

Cited By ~ 2

Author(s):

Olga Kaltsa ◽

Spyros Grigorakis ◽

Achillia Lakka ◽

Eleni Bozinou ◽

Stavros Lalas ◽

...

Keyword(s):

High Performance ◽

Deep Eutectic Solvent ◽

Deep Eutectic Solvents ◽

Process Variable ◽

Molar Ratio ◽

Olive Leaves ◽

Total Polyphenol ◽

Solid Ratio ◽

Wide Range ◽

Efficient Recovery

Olive leaves (OLL) are considered to be a highly appreciated bioresource of bioactive polyphenolic phytochemicals, embracing several different structures. However, extraction processes based on deep eutectic solvents (DES) are very limited despite the wide range of techniques developed for the efficient recovery of polyphenols. This study had as objective the development of a simple, green, high-performance extraction methodology for OLL polyphenols, using a recently reported effective DES, composed of L-lactic acid and glycine. Initially, a screening was performed to select the most appropriate L-lactic/glycine molar ratio and process optimization was then carried out with response surface methodology. The optimized process variable values were DES/water (78% w/v), liquid-to-solid ratio of 36 mL g−1, and stirring speed of 500 rounds per minute, and the total polyphenol yield amounted to 97.53 ± 3.54 mg gallic acid equivalents per g dry matter. Extraction with DES at 80 °C did not significantly increase the total polyphenol yield, but it did enhance the total flavonoid yield and antioxidant activity. High-performance liquid chromatography analyses revealed that extraction with the DES resulted in extended oleuropein hydrolysis, to the favor of hydroxytyrosol formation. This finding might have a prospect in using properly tuned DES for polyphenol modification with improved bioactivities.

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Environmentally-Friendly Extraction of Flavonoids from Cyclocarya paliurus (Batal.) Iljinskaja Leaves with Deep Eutectic Solvents and Evaluation of Their Antioxidant Activities

Molecules ◽

10.3390/molecules23092110 ◽

2018 ◽

Vol 23 (9) ◽

pp. 2110 ◽

Cited By ~ 15

Author(s):

Xianchao Shang ◽

Jia-Neng Tan ◽

Yongmei Du ◽

Xinmin Liu ◽

Zhongfeng Zhang

Keyword(s):

Antioxidant Activities ◽

Choline Chloride ◽

Radical Scavenging ◽

Deep Eutectic Solvent ◽

Environmentally Friendly ◽

Deep Eutectic Solvents ◽

Selective Extraction ◽

Molar Ratio ◽

Cyclocarya Paliurus

Deep eutectic solvents (DESs) are commonly employed as environmentally-friendly solvents in numerous chemical applications owing to their unique physicochemical properties. In this study, a novel and environmentally-friendly extraction method based on ultrasound assisted-deep eutectic solvent extraction (UAE-DES) was investigated for the extraction of flavonoids from Cyclocarya paliurus (Batal.) Iljinskaja (C. paliurus) leaves, and the antioxidant activities of these flavonoids were evaluated. Nine different DES systems based on either two or three components were tested, and the choline chloride/1,4–butanediol system (1:5 molar ratio) was selected as the optimal system for maximizing the flavonoid extraction yields. Other extraction conditions required to achieve the maximum flavonoid extraction yields from the leaves of C. paliurus were as follows: DES water content (v/v), 30%; extraction time, 30 min; temperature, 60 °C; and solid-liquid ratio, 20 mg/mL. Liquid chromatography-mass spectrometry allowed the detection of five flavonoids in the extract, namely kaempferol-7-O-α-l-rhamnoside, kaempferol, quercetin, quercetin-3-O-β-d-glucuronide, and kaempferol-3-O-β-d-glucuronide. In vitro antioxidant tests revealed that the flavonoid-containing extract exhibited strong DPPH and ABTS radical-scavenging abilities. Results indicate that UAE-DES is a suitable approach for the selective extraction of flavonoids from C. paliurus leaves, and DESs can be employed as sustainable extraction media for other bioactive compounds.

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Deep eutectic solvents for Cu-catalysed ARGET ATRP under an air atmosphere: a sustainable and efficient route to poly(methyl methacrylate) using a recyclable Cu(ii) metal–organic framework

Green Chemistry ◽

10.1039/c9gc02624j ◽

2019 ◽

Vol 21 (21) ◽

pp. 5865-5875 ◽

Cited By ~ 10

Author(s):

Luis Quirós-Montes ◽

Gabino A. Carriedo ◽

Joaquín García-Álvarez ◽

Alejandro Presa Soto

Keyword(s):

Methyl Methacrylate ◽

Metal Organic Framework ◽

Deep Eutectic Solvent ◽

Environmentally Friendly ◽

Deep Eutectic Solvents ◽

Poly Methyl Methacrylate ◽

Air Atmosphere ◽

Arget Atrp ◽

Metal Organic ◽

Efficient Route

A new environmentally-friendly and air-tolerant protocol for the Cu-MOF catalysed ATRP of MMA in a biorenewable deep eutectic solvent is reported, with both the solvent and catalyst being recycled up to six consecutive times.

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Environmentally Friendly Techniques and Their Comparison in the Extraction of Natural Antioxidants from Green Tea, Rosemary, Clove, and Oregano

Molecules ◽

10.3390/molecules26071869 ◽

2021 ◽

Vol 26 (7) ◽

pp. 1869

Author(s):

Mariel Calderón-Oliver ◽

Edith Ponce-Alquicira

Keyword(s):

Green Tea ◽

Electric Fields ◽

Antioxidant Activities ◽

Environmentally Friendly ◽

Natural Antioxidants ◽

Deep Eutectic Solvents ◽

Extraction Methods ◽

Extraction Techniques ◽

Health Trends ◽

Food Applications

Many current food and health trends demand the use of more ecological, sustainable, and environmentally friendly techniques for the extraction of bioactive compounds, including antioxidants. However, extraction yields and final antioxidant activities vary between sources and are highly influenced by the given extraction method and nature and ratio of the employed solvent, especially for total polyphenols, flavonoids, and anthocyanins, which are well recognized as natural antioxidants with food applications. This review focused on the most common extraction techniques and potential antioxidant activity in the food industry for various natural antioxidant sources, such as green tea, rosemary, clove, and oregano. Green extraction techniques have been proven to be far more efficient, environmentally friendly, and economical. In general, these techniques include the use of microwaves, ultrasound, high hydrostatic pressure, pulsed electric fields, enzymes, and deep eutectic solvents, among others. These extraction methods are described here, including their advantages, disadvantages, and applications.

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Toxico-metabolomics study of a deep eutectic solvent comprising choline chloride and urea suggests in vivo toxicity involving oxidative stress and ammonia stress

Green Chemistry ◽

10.1039/d0gc03927f ◽

2021 ◽

Vol 23 (3) ◽

pp. 1300-1311 ◽

Cited By ~ 1

Author(s):

Dasom Jung ◽

Jae Back Jung ◽

Seulgi Kang ◽

Ke Li ◽

Inseon Hwang ◽

...

Keyword(s):

Oxidative Stress ◽

Choline Chloride ◽

Deep Eutectic Solvent ◽

Deep Eutectic Solvents ◽

In Vivo Toxicity ◽

Metabolomics Study ◽

Ammonia Stress

The in vitro and in vivo studies suggest that choline chloride-based deep eutectic solvents may not be considered as pure, safe mixtures even if they consist of safe compounds.

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Deep Eutectic Solvents Based Choline Chloride for Enzymatic Biodiesel Production from Degumming Palm Oil

Asian Journal of Chemistry ◽

10.14233/ajchem.2020.22193 ◽

2020 ◽

Vol 32 (4) ◽

pp. 733-738 ◽

Cited By ~ 1

Author(s):

R. Manurung ◽

Taslim ◽

A.G.A. Siregar

Keyword(s):

Palm Oil ◽

Raw Materials ◽

Choline Chloride ◽

Deep Eutectic Solvent ◽

Deep Eutectic Solvents ◽

Biodiesel Production ◽

Chloride Salt ◽

Enzymatic Reactions ◽

Potential Applications ◽

Palm Oil Biodiesel

Deep eutectic solvents (DESs) have numerous potential applications as cosolvents. In this study, use of DES as organic solvents for enzymatic biodiesel production from degumming palm oil (DPO) was investigated. Deep eutectic solvent was synthesized using choline chloride salt (ChCl) compounds with glycerol and 1,2-propanediol. Deep eutectic solvent was characterized by viscosity, density, pH and freezing values, which were tested for effectiveness by enzymatic reactions for the production of palm biodiesel with raw materials DPO. Deep eutectic solvent of ChCl and glycerol produced the highest biodiesel yield (98.98%); weight of DES was only 0.5 % of that of the oil. In addition, the use of DES maintained the activity and stability of novozym enzymes, which was assessed as the yield until the 6th usage, which was 95.07 % biodiesel yield compared with the yield without using DES. Hence, using DES, glycerol in enzymatic biodiesel production had high potentiality as an organic solvent for palm oil biodiesel production

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Deep Eutectic Solvents for the Valorisation of Lignocellulosic Biomasses towards Fine Chemicals

Biomass ◽

10.3390/biomass1010003 ◽

2021 ◽

Vol 1 (1) ◽

pp. 29-59

Author(s):

Enrico Scelsi ◽

Antonella Angelini ◽

Carlo Pastore

Keyword(s):

Environmental Impact ◽

Lignocellulosic Biomass ◽

Deep Eutectic Solvent ◽

Modern Society ◽

Deep Eutectic Solvents ◽

Critical Discussion ◽

Fine Chemicals ◽

Enzymatic Transformation ◽

Alternative Sources ◽

Industrial Level

The growing demand for energy and materials in modern society pushes scientific research to finding new alternative sources to traditional fossil feedstocks. The exploitation of biomass promises to be among the viable alternatives with a lower environmental impact. Making biomass exploitation technologies applicable at an industrial level represents one of the main goals for our society. In this work, the most recent scientific studies concerning the enhancement of lignocellulosic biomasses through the use of deep eutectic solvent (DES) systems have been examined and reported. DESs have an excellent potential for the fractionation of lignocellulosic biomass: the high H-bond capacity and polarity allow the lignin to be deconvolved, making it easier to break down the lignocellulosic complex, producing a free crystallite of cellulose capable of being exploited and valorised. DESs offer valid alternatives of using the potential of lignin (producing aromatics), hemicellulose (achieving furfural) and cellulose (delivering freely degradable substrates through enzymatic transformation into glucose). In this review, the mechanism of DES in the fractionation of lignocellulosic biomass and the main possible uses for the valorisation of lignin, hemicellulose and cellulose were reported, with a critical discussion of the perspectives and limits for industrial application.

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