scholarly journals Combining acid-based deep eutectic solvents and microwave irradiation for improved chestnut shell waste valorization

2021 ◽  
Author(s):  
José González-Rivera ◽  
Angelica Mero ◽  
Elena Husanu ◽  
Andrea Mezzetta ◽  
Carlo Ferrari ◽  
...  
Keyword(s):  
Microwave Irradiation ◽  
Deep Eutectic Solvent ◽  
Deep Eutectic Solvents ◽  
Waste Valorization ◽  
Simultaneous Extraction ◽  
Microwave Assisted ◽  
Chestnut Shell ◽  
Shell Waste ◽  
Key Features

Key features of the deep eutectic solvent-microwave assisted simultaneous extraction of polyphenols and delignification pretreatment of chestnut shell waste are presented.

scholarly journals Microwave-Assisted Simultaneous Extraction of Luteolin and Apigenin from Tree Peony Pod and Evaluation of Its Antioxidant Activity

2014 ◽  
Vol 2014 ◽  
pp. 1-12 ◽  
Author(s):  
Hongzheng Wang ◽  
Lei Yang ◽  
Yuangang Zu ◽  
Xiuhua Zhao
Keyword(s):  
Microwave Irradiation ◽  
Volume Fraction ◽  
Antioxidant Activities ◽  
Radical Scavenging ◽  
Reducing Power ◽  
Optimal Conditions ◽  
Tree Peony ◽  
Antioxidant Power ◽  
Simultaneous Extraction ◽  
Microwave Assisted

An efficient microwave-assisted extraction (MAE) technique was employed in simultaneous extraction of luteolin and apigenin from tree peony pod. The MAE procedure was optimized using response surface methodology (RSM) and compared with other conventional extraction techniques of macerate extraction (ME) and heat reflux extraction (HRE). The optimal conditions of MAE were as follows: employing 70% ethanol volume fraction as solvent, soaking time of 4 h, liquid-solid ratio of 10 (mL/g), microwave irradiation power of 265 W, microwave irradiation time of 9.6 min, and 3 extraction cycles. Under the optimal conditions, 151 μg/g luteolin and 104 μg/g apigenin were extracted from the tree peony pod. Compared with ME and HRE, MAE gave the highest extraction efficiency. The antioxidant activities of the extracts obtained by MAE, ME, and HRE were evaluated using a 2,2-di(4-tert-octylphenyl)-1-picrylhydrazyl (DPPH) free radical-scavenging assay, a ferric reducing antioxidant power assay (FRAP), and a reducing power assay. Meanwhile, the structural changes of the unprocessed and processed tree peony pod samples were analyzed by scanning electron microscopy.

Choline-Based Deep Eutectic Solvent and Microwave Irradiation as Tools for PET Identification in Blend Fabric

2021 ◽  
Vol 8 (1) ◽  
pp. 40-50
Author(s):  
Samuel Choi ◽  
Hyung-Min Choi
Keyword(s):  
Microwave Irradiation ◽  
Choline Chloride ◽  
Deep Eutectic Solvent ◽  
Deep Eutectic Solvents ◽  
Test Method ◽  
Toxic Chemicals ◽  
Practical Application ◽  
Commercial Sample ◽  
Treatment Medium ◽  
Blend Fabric

A new, rapid, and eco-friendly technique for identification of polyethylene terephthalate (PET) composition in blend fabric was developed. This technique could replace a conventional composition identification of PET using toxic chemicals such as halogenated organic solvent or strong inorganic acid. Choline-based deep eutectic solvents (DES), such as ethylene glycol- choline chloride, were used as a treatment medium under microwave irradiation. The PET portion of the blend fabrics, such as 65/35 and 50/50 PET/cotton was completely removed by DES containing 5% NaOH (w/v) after 100–140 s of microwave irradiation. Various instrumental analyses confirmed the removal of PET. Finally, a commercial sample was also tested as a practical application of the new test method.

scholarly journals Exploiting Deep Eutectic Solvents and Ionic Liquids for the Valorization of Chestnut Shell Waste

2020 ◽  
Vol 8 (50) ◽  
pp. 18386-18399
Author(s):  
Elena Husanu ◽  
Angelica Mero ◽  
Jose Gonzalez Rivera ◽  
Andrea Mezzetta ◽  
Julian Cabrera Ruiz ◽  
...  
Keyword(s):  
Ionic Liquids ◽  
Deep Eutectic Solvents ◽  
Chestnut Shell ◽  
Shell Waste

The extraction of phenolic acids and polysaccharides from Lilium lancifolium Thunb. using a deep eutectic solvent

2021 ◽  
Author(s):  
Lin Chen ◽  
Yang-Yu Yang ◽  
Rong-rong Zhou ◽  
Liang-zi Fang ◽  
Di Zhao ◽  
...  
Keyword(s):  
Phenolic Acids ◽  
Deep Eutectic Solvent ◽  
Deep Eutectic Solvents ◽  
Simultaneous Extraction ◽  
Lilium Lancifolium

This study provided a new application of deep eutectic solvents (DESs) in the simultaneous extraction of phenolic acids and polysaccharides from the bulbs of Lilium lancifolium Thunb.

Regioselective Synthesis of Potent 4,5,6,7-Tetrahydroindazole Derivatives via Microwave-assisted Vilsmeier-Haack Reaction and their Antioxidant Activity Evaluation

2019 ◽  
Vol 16 (3) ◽  
pp. 194-201 ◽  
Author(s):  
Renu Bala ◽  
Vandana Devi ◽  
Pratibha Singh ◽  
Navjot Kaur ◽  
Pawandeep Kaur ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
Microwave Irradiation ◽  
Biological Activities ◽  
Reaction Times ◽  
Conventional Heating ◽  
High Chemical ◽  
Microwave Assisted ◽  
Work Up ◽  
Active Methylene ◽  
By Products

Background: Tetrahydroindazole, a member of the fused-pyrazole system, is a least studied class of heterocyclic compounds owing to its scarcity in nature. However, a large number of synthetically prepared tetrahydroindazoles are known to show a variety of biological activities such as interleukin- 2 inducible T-Cell kinase inhibitors, AMPA receptor positive allosteric modulators, antitumor, antituberculosis, anti-inflammatory and antimicrobial activities. Vilsmeier-Haack reaction is one of the most important chemical reactions used for formylation of electron rich arenes. Even though Vilsmeier- Haack reaction was studied on a wide variety of hydrazones derived from active methylene compounds, literature lacks the examples of the use of 4-substituted cyclohexanones as a substrate for the synthesis of 4,5,6,7-tetrahydroindazoles. The study of the reaction of Vilsmeier-Haack reagent with hydrazones derived from cyclic keto compounds having active methylene has been considered the interested topic of investigation. In the present study, ethyl cyclohexanone-4-carboxylate was treated with one equivalent of various hydrazines for two hours and the resulted hydrazones were further treated with an OPC-VH reagent (Vilsmeier-Haack reagent isolated from phthaloyl dichloride and N,Ndimethylformamide) afforded 4,5,6,7-tetrahydroindazoles in excellent yields. The synthesized compounds 4a-f and 5a-f were screened for their antioxidant activities using the DPPH radical scavenging assay. The target compounds were synthesized regioselectively using 4+1 approach in excellent yields. A number of experiments using both conventional heating as well as microwave irradiation methods were tried and on comparison, microwave irradiation method was found excellent in terms of easy work up, high chemical yields, shortened reaction times, clean and, no by-products formation. Some of the synthesized compounds showed significant antioxidant activity. The microwave assisted synthesis of 4,5,6,7-tetrahydroindazoles from ethyl cyclohexanone-4-carboxylate has been reported under mild conditions in excellent yield. Easy work up, high chemical yield, shortened reaction times, clean and no by-products formation are the major advantages of this protocol. These advantages may make this method useful for chemists who are interested in developing novel 4,5,6,7-tetrahydroindazole based drugs.

Microwave-assisted Synthesis of Benzoxazoles Derivatives

2020 ◽  
Vol 7 (3) ◽  
pp. 183-195
Author(s):  
Musa Özil ◽  
Emre Menteşe
Keyword(s):  
Microwave Irradiation ◽  
Reaction Medium ◽  
Pharmaceutical Chemistry ◽  
Conventional Heating ◽  
High Yield ◽  
Microwave Assisted Synthesis ◽  
Microwave Assisted ◽  
Optical Brighteners ◽  
Chemistry Research ◽  
Extensive Class

Background: Benzoxazole, containing a 1,3-oxazole system fused with a benzene ring, has a profound effect on medicinal chemistry research owing to its important pharmacological activities. On the other hand, the benzoxazole derivative has exhibited important properties in material science. Especially in recent years, microwave-assisted synthesis is a technique that can be used to increase diversity and quick research in modern chemistry. The utilization of microwave irradiation is beneficial for the synthesis of benzoxazole in recent years. In this focused review, we provide a metaanalysis of studies on benzoxazole in different reaction conditions, catalysts, and starting materials by microwave technique so far, which is different from conventional heating. Methods: Synthesis of different kind of benzoxazole derivatives have been carried out by microwave irradiation. The most used method to obtain benzoxazoles is the condensation of 2-aminophenol or its derivatives with aldehydes, carboxylic acids, nitriles, isocyanates, and aliphatic amines. Results: Benzoxazole system and its derivatives have exhibited a broad range of pharmacological properties. Thus, many scientists have remarked on the importance of the synthesis of different benzoxazole derivatives. Conventional heating is a relatively inefficient and slow method to convey energy in orientation to the reaction medium. However, the microwave-assisted heating technique is a more effective interior heating by straight coupling of microwave energy with the molecules. Conclusion: In this review, different studies were presented on the recent details accessible in the microwave- assisted techniques on the synthesis of the benzoxazole ring. It presents all examples of such compounds that have been reported from 1996 to the present. Benzoxazoles showed an extensive class of chemical substances not only in pharmaceutical chemistry but also in dyestuff, polymer industries, agrochemical, and optical brighteners. Thus the development of fast and efficient achievement of benzoxazoles with a diversity of substituents in high yield is getting more noteworthy. As shown in this review, microwave-assisted synthesis of benzoxazoles is a very effective and useful technique.

scholarly journals Microwave assisted transesterification of biodiesel from waste cooking oil using CaO extracted from green mussel shell waste and limestone as catalyst

2021 ◽  
Author(s):  
Budiani F. Endrawati ◽  
Niar K. Julianti ◽  
Azmia R. Nafisah ◽  
Chandra S. Rahendaputri ◽  
Endah Mutiara
Keyword(s):  
Waste Cooking Oil ◽  
Mussel Shell ◽  
Green Mussel ◽  
Microwave Assisted ◽  
Cooking Oil ◽  
Shell Waste

scholarly journals Microwave-Assisted Asinger Synthesis of Thiazolines

2020 ◽  
Vol 3 (1) ◽  
pp. 27
Author(s):  
Raúl Eduardo Gordillo-Cruz ◽  
Liliana Gonzalez-Reyes ◽  
Milton Coporo-Reyes ◽  
Nieves Zavala-Segovia ◽  
Bernardo A. Frontana-Uribe ◽  
...  
Keyword(s):  
Microwave Irradiation ◽  
Reaction Times ◽  
Reaction Conditions ◽  
Microwave Assisted

An array of 2,4-disubstituted thiazolines was obtained through Asinger reaction approach from the straightforward treatment of diverse aldehydes/ketones with 1-mercaptopropan-2-one, in the presence of NH3 assisted by microwave irradiation, displaying similar and sometimes higher yields, as well as shorter reaction times that traditional Asinger reaction conditions at room and lower temperatures.

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

2021 ◽  
Vol 23 (3) ◽  
pp. 1300-1311 ◽  
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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