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Rapid extraction of bisphenol a by dispersive liquid-liquid microextraction based on solidification of floating organic

Shan TO, Mee LN, Marinah Mohd Ariffin, Saw HL

Sains Malaysiana, 2017;46:615-621.

Bisphenol A is an endocrine disruptor with widespread applications, especially in the production of polycarbonate and epoxy resins. Dispersive liquid-liquid microextraction based on solidification of floating organic technique has been developed for the extraction of bisphenol A from water and soft drink. The 1-undecanol has been applied as the extraction solvent because of its low density and melting point and high affinity to the analyte. The technique offered rapid and simple analysis as the 1-undecanol was homogeneously dispersed in the sample solution to speed the extraction and the collection of extraction solvent was simplified by centrifugation, cooling and melting steps.

Matched MeSH terms: Solvents
Profiling of cured residue of solvent-based adhesives by attenuated total reflectance-Fourier transform infrared spectroscopy with chemometrics for forensic investigation

Saman SA, Chang KH, Abdullah AFL

J Forensic Sci, 2021 Mar;66(2):608-618.
PMID: 33202056 DOI: 10.1111/1556-4029.14625

Abuse of solvent-based adhesives jeopardizes world population, especially the young generation. Adhesive-related exhibits encountered in forensic cases might need to be determined if they could have come from a particular source or to establish link between cases or persons. This study was aimed to discriminate solvent-based adhesives, especially to aid forensic investigation of glue sniffing activities. In this study, thirteen brands with three samples each, totaling at 39 adhesive samples, were analyzed using attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy followed by chemometric methods. Experimental output showed that adhesive samples utilized in this study were less likely to change in their ATR-FTIR profiles over time, at least up to 2 months. No interference from plastic materials was noticed based on ATR-FTIR profile comparison. Physical examination could differentiate the samples into two groups, namely contact adhesives and cement adhesives. A principal component analysis-score linear discriminative analysis (PC-score LDA) model resulted in 100% and 98.6% correct classification in discriminating the two groups of adhesive samples, forming seven discriminative clusters. Test set with adhesive samples applied glass slide and plastic substrates also demonstrated a 100% correct classification into their respective groups. As a conclusion, the method allowed for discrimination of adhesive samples based on the spectral features, displaying relationship among samples. It is hoped that this comparative information is beneficial to trace the possible source of solvent-based adhesives, whenever they are recovered from a crime scene, for forensic investigation.

Matched MeSH terms: Solvents
Fulltext Combating insolvency and business recovery problems in the oil industry: proposal for improvement in Nigeria's insolvency and bankruptcy legal framework

Olujobi OJ

Heliyon, 2021 Feb;7(2):e06123.
PMID: 33659729 DOI: 10.1016/j.heliyon.2021.e06123

Insolvency and business recovery laws in Nigeria have not evolved to incorporate reorganisation, reforming insolvent oil firms' operations to boost commercial oil firms' steadiness and economic suitability like other moderately developed countries. In Nigeria, liquidation is understood by many as the panacea to indebtedness. The research evaluates the Nigerian insolvency and business recovery legal regime to sustain indebted oil firms from economic shocks due to the global decline in the oil price to avert imminent business failures due to insufficient cash flows. The aim is to fill the gaps in Nigeria's insolvency and business recovery laws by recommending a model for the sustenance of oil firms and to suggest the reform of the gaps identified in the existing laws and the extant literature on the subject. The paper opted for conceptual legal review, comparative legal and policies analyses of solvency and business recovery legislations in Nigeria, Malaysia, India, South Africa, the United Kingdom and the United States. These nations were designated for this study because their insolvency and business recovery legal regime are business rescued driven, not winding up centred. The study is library research-based to address some of the flaws in Nigeria's insolvency and business recovery laws. The study finds that Nigerian legislation on insolvency is flawed in oil firms' salvage, improvement and rearrangement. It ends that, statutory bodies in the designated case study nations are efficient than those in Nigeria due to the strong political will of their governments in supporting insolvent oil firms for successful financial recovery, to safeguard jobs, to protect creditors and to enhance the wealth of their nations through sound business recovery policies and laws. The study, advocates, remodel of Nigeria's insolvency and business recovery legislations and policies in compliance with the international standards on insolvent oil firms salvaged and creditors focused policies for a robust economy. The study concludes with the recommendation for further study to consider quantitative analysis research methodology to project further scholarship on the subject.

Matched MeSH terms: Solvents
Fulltext Evaluation of extraction solvent on antioxidant activity, total phenolic and total flavonoid content in Elaeis Guineensis

Wan Zuraida Wan Mohd Zain, Siti Nur Lisha Mohd Ghazali, Samsiah Jusoh

ESTEEM Academic Journal, 2019;15(1):25-32.
MyJurnal

Oil palm or Elaeis guineens is a rich natural source of phenolic with flavonoid as the main constituents. These phenolics are potent antioxidants that can be used in the food industry, cosmetics and others. Therefore, the study was aimed to determine the effect of solvents which were methanol, ethyl acetate and hexane also different plant parts which were leaves, frond and fresh fruit bunch toward antioxidant activity (AOA), total phenolic content (TPC) and total flavonoid
content (TFC). The antioxidant was analysed using the DPPH method, TPC by Ciocalteu assay and TFC by aluminium chloride colorimetric assay. The result from ANOVA indicated that there was a difference (P < 0.05) in the extracting ability of each solvent and different plant parts for AOA, TPC and TFC. Generally, the result suggested that methanol give the highest antioxidant
activity, TPC and TFC compared to ethyl acetate and hexane. Therefore, the solvent used should be selected properly to allow for a high level of extraction efficiency.

Matched MeSH terms: Solvents
Fulltext Determination of Temperature-Dependent Coefficients of Viscosity and Surface Tension of Tamarind Seeds (Tamarindus indica L.) Polymer

Malviya R, Jha S, Fuloria NK, Subramaniyan V, Chakravarthi S, Sathasivam K, et al.

Polymers (Basel), 2021 Feb 18;13(4).
PMID: 33670569 DOI: 10.3390/polym13040610

The rheological properties of tamarind seed polymer are characterized for its possible commercialization in the food and pharmaceutical industry. Seed polymer was extracted using water as a solvent and ethyl alcohol as a precipitating agent. The temperature's effect on the rheological behavior of the polymeric solution was studied. In addition to this, the temperature coefficient, viscosity, surface tension, activation energy, Gibbs free energy, Reynolds number, and entropy of fusion were calculated by using the Arrhenius, Gibbs-Helmholtz, Frenkel-Eyring, and Eotvos equations, respectively. The activation energy of the gum was found to be 20.46 ± 1.06 kJ/mol. Changes in entropy and enthalpy were found to be 23.66 ± 0.97 and -0.10 ± 0.01 kJ/mol, respectively. The calculated amount of entropy of fusion was found to be 0.88 kJ/mol. A considerable decrease in apparent viscosity and surface tension was produced when the temperature was raised. The present study concludes that the tamarind seed polymer solution is less sensitive to temperature change in comparison to Albzia lebbac gum, Ficus glumosa gum and A. marcocarpa gum. This study also concludes that the attainment of the transition state of viscous flow for tamarind seed gum is accompanied by bond breaking. The excellent physicochemical properties of tamarind seed polymers make them promising excipients for future drug formulation and make their application in the food and cosmetics industry possible.

Matched MeSH terms: Solvents
Fulltext A review on extraction techniques and therapeutic value of polar bioactives from Asian medicinal herbs: Case study on Orthosiphon aristatus, Eurycoma longifolia and Andrographis paniculata

Abd Aziz NA, Hasham R, Sarmidi MR, Suhaimi SH, Idris MKH

Saudi Pharm J, 2021 Feb;29(2):143-165.
PMID: 33679177 DOI: 10.1016/j.jsps.2020.12.016

Medicinal plants have gained much interest in the prevention and treatment of common human disease such as cold and fever, hypertension and postpartum. Bioactive compounds from medicinal plants were synthesised using effective extraction methods which have important roles in the pharmaceutical product development. Orthosiphon aristatus (OA), Eurycoma longifolia (EL) and Andrographis paniculata (AP) are among popular medicinal herbs in Southeast Asia. The major compounds for these medicinal plants are polar bioactive compounds (rosmarinic acid, eurycomanone and andrographolide) which have multiple benefits to human health. The bioactive compounds are used as a drug to function against a variety of diseases with the support of scientific evidence. This paper was intended to prepare a complete review about the extraction techniques (e.g. OA, EL and AP) of these medicinal plants based on existing studies and scientific works. Suitable solvents and techniques to obtain their major bioactive compounds and their therapeutic potentials were discussed.

Matched MeSH terms: Solvents
Fulltext Current Pretreatment/Cell Disruption and Extraction Methods Used to Improve Intracellular Lipid Recovery from Oleaginous Yeasts

Zainuddin MF, Fai CK, Ariff AB, Rios-Solis L, Halim M

Microorganisms, 2021 Jan 27;9(2).
PMID: 33513696 DOI: 10.3390/microorganisms9020251

The production of lipids from oleaginous yeasts involves several stages starting from cultivation and lipid accumulation, biomass harvesting and finally lipids extraction. However, the complex and relatively resistant cell wall of yeasts limits the full recovery of intracellular lipids and usually solvent extraction is not sufficient to effectively extract the lipid bodies. A pretreatment or cell disruption method is hence a prerequisite prior to solvent extraction. In general, there are no recovery methods that are equally efficient for different species of oleaginous yeasts. Each method adopts different mechanisms to disrupt cells and extract the lipids, thus a systematic evaluation is essential before choosing a particular method. In this review, mechanical (bead mill, ultrasonication, homogenization and microwave) and nonmechanical (enzyme, acid, base digestions and osmotic shock) methods that are currently used for the disruption or permeabilization of oleaginous yeasts are discussed based on their principle, application and feasibility, including their effects on the lipid yield. The attempts of using conventional and "green" solvents to selectively extract lipids are compared. Other emerging methods such as automated pressurized liquid extraction, supercritical fluid extraction and simultaneous in situ lipid recovery using capturing agents are also reviewed to facilitate the choice of more effective lipid recovery methods.

Matched MeSH terms: Solvents
Fulltext Characterization of the key aroma compounds in three types of bagels by means of the sensomics approach

Lasekan O, Dabaj F, Muniandy M, Juhari NH, Lasekan A

BMC Chem, 2021 Mar 13;15(1):16.
PMID: 33714268 DOI: 10.1186/s13065-021-00743-4

BACKGROUND: To evaluate the impact of cold fermentation time on bagel rolls, the key aroma-active compounds in the volatile fractions obtained from three different bagel rolls through solvent assisted flavor evaporation (SAFE) were sequentially characterized by an aroma extract dilution analysis (AEDA), quantified by stable isotope dilution and analyzed by odor activity values (OAVs) respectively.
RESULTS: Findings revealed 40 aroma-active compounds with flavor dilution (FD) factor ranges of 2-1024. Of these, 22 compounds (FD ≥ 16) were quantified by stable isotope dilution assays (SIDA). Subsequent analysis of the 22 compounds by odor activity values (OAVs) revealed 14 compounds with OAVs ≥ 1 and the highest concentrations were obtained for 2,3-butanedione, 2-phenylethanol, 3-methylbutanal and acetoin respectively. Two recombination models of the bagels (i.e. 24 h and 48 h bagels) showed similarity to the corresponding bagels. Omission tests confirmed that 2,3-butanedione (buttery), acetoin (buttery), 2-acetyl-1-pyrroline (roasty), 5-methyl-2-furanmethanol (bread-like), (Z)-4-heptenal (biscuit-like) and 4-hydroxy-2,5-dimethyl-3(2H)-furanone, were the key aroma compounds. Additionally, acetic acid, butanoic acid, 2-phenylethanol (honey-like), 3-methylbutanoic acid, 2/3-methylbutanal, vanillin, 3-methylbutanol, methional were also important odorants of the bagel.
CONCLUSION: Whilst the long, cold fermented bagels exhibited roasty, malty, buttery, baked potato-like, smoky and biscuit-like notes, the control bagels produced similar but less intense odor notes.

Matched MeSH terms: Solvents
Fulltext Chemical and Thermo-Mechanical Properties of Waterborne Polyurethane Dispersion Derived from Jatropha Oil

Saalah S, Abdullah LC, Aung MM, Salleh MZ, Awang Biak DR, Basri M, et al.

Polymers (Basel), 2021 Mar 05;13(5).
PMID: 33807622 DOI: 10.3390/polym13050795

Nowadays, there is a significant trend away from solvent-based polyurethane systems towards waterborne polyurethane dispersions due to government regulations requiring manufacturers to lower total volatile organic compounds, as well as consumer preference for more environmentally friendly products. In this work, a renewable vegetable oil-based polyol derived from jatropha oil was polymerized with isophorone diisocyanate and dimethylol propionic acid to produce anionic waterborne polyurethane dispersion. Free standing films with up to 62 wt.% bio-based content were successfully produced after evaporation of water from the jatropha oil-based waterborne polyurethane (JPU) dispersion, which indicated good film formation. The chemical and thermo-mechanical properties of the JPU films were characterized. By increasing the OH numbers of polyol from 161 mgKOH/g to 217 mgKOH/g, the crosslinking density of the JPU was significantly increased, which lead to a better storage modulus and improved hydrophobicity. Overall, JPU produced from polyol having OH number of 217 mgKOH/g appears to be a promising product for application as a binder for wood and decorative coatings.

Matched MeSH terms: Solvents
Fulltext In vitro cytotoxic and antimicrobial activities of Erythrina suberosa (Roxb) bark

Ahmed Z, Aziz S, Alauddin S, Mohiuddin SG, Javed A, Ahmed R, et al.

J Pharm Bioallied Sci, 2020 04 10;12(2):210-216.
PMID: 32742121 DOI: 10.4103/jpbs.JPBS_223_19

Background: The study was focused on evaluating cytotoxic and antimicrobial activities of Erythrina suberosa (Roxb.) bark through in vitro pharmacological screening.
Materials and Methods: The bark was extracted using different solvents, for example, dichloromethane, ethyl acetate, methanol, and aqueous for obtaining the organic fractions. These organic fractions were then evaluated for their cytotoxic and antimicrobial activity compared with the standard. Cefixime was used as the standard for antibacterial assay, whereas clotrimazole was used as the standard for antifungal activities. Bacterial strains used were Staphylococcus aureus and methicillin-resistant S. aureus (MRSA), whereas for antifungal activities Candida albicans, Candida parapsilosis, and Candida krusei strains were used.
Results: The organic fractions obtained were evaluated for their cytotoxic and antimicrobial activities. In cytotoxic assay (Brine shrimp lethality assay), dichloromethane fraction was the most potent with LD50 of 47.63, whereas aqueous, methanol, and ethyl acetate fractions showed LD50 of 121.74, 422.2, and 201.96, respectively. Similarly, for antibacterial assay, dichloromethane fraction showed 32.2mm zone of inhibition against MRSA in comparison with standard cefixime (zone of inhibition, 30.5mm). A minimal zone of inhibition with crude saponins (13.1 and 12.2mm) was observed against C. albicans in comparison to standard (cefixime) with a zone of inhibition of 28.5mm. No prominent results were observed against C. parapsilosis and C. krusei strains.
Conclusion: The study was based on the plant from Indo-Pak origin, and it has shown some prominent cytotoxic and antibacterial activities. Although the results of this study have provided a basic idea about the efficacy of plant extract, still more explanatory and high-scale studies can be beneficial for elaborating the cytotoxic and antimicrobial activities of this plant.

Matched MeSH terms: Solvents
Fulltext Preparation and Characterization of Polyphenylsulfone (PPSU) Membranes for Biogas Upgrading

Kujawski W, Li G, Van der Bruggen B, Pedišius N, Tonkonogij J, Tonkonogovas A, et al.

Materials (Basel), 2020 Jun 25;13(12).
PMID: 32630434 DOI: 10.3390/ma13122847

Asymmetric polyphenylsulfone (PPSU) membranes were fabricated by a non-solvent induced phase inversion method. Glycerin and silica nanoparticles were added into the polymer solution to investigate their effects on the material properties and gas separation performance of prepared membranes. The morphology and structure of PPSU membranes were analyzed by scanning electron microscopy (SEM), the surface roughness of the selective layer was analyzed by atomic force microscopy (AFM), and the surface free energy was calculated based on the contact angle measurements by using various solvents. The gas separation performance of PPSU membranes was estimated by measuring the permeability of CO2 and CH4. The addition of glycerin as a nonsolvent into the polymer solution changed the cross-section structure from finger-like structure into sponge-like structure due to the delayed liquid-liquid demixing process, which was confirmed by SEM analysis. The incorporation of silica nanoparticles into PPSU membranes slightly increased the hydrophilicity, which was confirmed by water contact angle results. PPSU membrane fabricated from the polymer solution containing 10 wt.% glycerin showed the best CO2/CH4 selectivity of 3.86 and the CO2 permeability of 1044.01 Barrer. Mixed matrix PPSU membrane containing 0.1 wt.% silica nanoparticles showed the CO2/CH4 selectivity of 3.16 and the CO2 permeability of 1202.77 Barrer.

Matched MeSH terms: Solvents
Preparation of Medicinal Plants: Basic Extraction and Fractionation Procedures for Experimental Purposes

Abubakar AR, Haque M

J Pharm Bioallied Sci, 2020 01 29;12(1):1-10.
PMID: 32801594 DOI: 10.4103/jpbs.JPBS_175_19

Preparation of medicinal plants for experimental purposes is an initial step and key in achieving quality research outcome. It involves extraction and determination of quality and quantity of bioactive constituents before proceeding with the intended biological testing. The primary objective of this study was to evaluate various methods used in the preparation and screening of medicinal plants in our daily research. Although the extracts, bioactive fractions, or compounds obtained from medicinal plants are used for different purposes, the techniques involved in producing them are generally the same irrespective of the intended biological testing. The major stages included in acquiring quality bioactive molecule are the selection of an appropriate solvent, extraction methods, phytochemical screening procedures, fractionation methods, and identification techniques. The nitty-gritty of these methods and the exact road map followed solely depends on the research design. Solvents commonly used in extraction of medicinal plants are polar solvent (e.g., water, alcohols), intermediate polar (e.g., acetone, dichloromethane), and nonpolar (e.g., n-hexane, ether, chloroform). In general, extraction procedures include maceration, digestion, decoction, infusion, percolation, Soxhlet extraction, superficial extraction, ultrasound-assisted, and microwave-assisted extractions. Fractionation and purification of phytochemical substances are achieved through application of various chromatographic techniques such as paper chromatography, thin-layer chromatography, gas chromatography, and high-performance liquid chromatography. Finally, compounds obtained are characterized using diverse identification techniques such as mass spectroscopy, infrared spectroscopy, ultraviolet spectroscopy, and nuclear magnetic resonance spectroscopy. Subsequently, different methods described above can be grouped and discussed according to the intended biological testing to guide young researchers and make them more focused.

Matched MeSH terms: Solvents
Fulltext Corn Starch/Chitosan Nanoparticles/Thymol Bio-Nanocomposite Films for Potential Food Packaging Applications

Othman SH, Othman NFL, Shapi'i RA, Ariffin SH, Yunos KFM

Polymers (Basel), 2021 Jan 27;13(3).
PMID: 33513664 DOI: 10.3390/polym13030390

This work aims to develop corn starch/chitosan nanoparticles/thymol (CS/CNP/Thy) bio-nanocomposite films as potential food packaging materials that can enhance the shelf life of food. CS/CNP/Thy bio-nanocomposite films were prepared by the addition of different concentrations of thymol (0, 1.5, 3.0, 4.5 w/w%) using a solvent casting method. The resulting films were characterized in terms of optical, mechanical, and water vapor permeability (WVP) properties. The addition of thymol was found to reduce the tensile strength (TS), elongation at break (EAB), and Young's modulus (YM) of the films. Generally, the increment in the concentration of thymol did not significantly affect the TS, EAB, and YM values. The addition of 1.5 w/w% thymol increased the WVP of the films but the WVP reduced with the increase in thymol concentrations. CS/CNP/Thy-3% bio-nanocomposite films demonstrated the potential to lengthen the shelf life of cherry tomatoes packed with the films, whereby the cherry tomatoes exhibited no significant changes in firmness and the lowest weight loss. In addition, no mold growth was observed on the sliced cherry tomatoes that were in direct contact with the films during 7 days of storage, proving the promising application of the films as active food packaging materials.

Matched MeSH terms: Solvents
Report - Synthesis of new antibacterial agents encompassing tosyl, piperidine, propanamide and 1,3,4-oxadiazole functionalities

Sattar A, Aziz-Ur-Rehman -, Abbasi MA, Siddiqui SZ, Rasool S, Ali Shah SA

Pak J Pharm Sci, 2020 Jul;33(4):1697-1705.
PMID: 33583804

A series of propanamide compounds 6a-l was derived by N-substitution reactions, encompassing tosyl, piperidine and 1,3,4-oxadiazole moieties. The intended array of compounds 6a-l was afforded by a series of five steps reaction scheme. 1-Tosylpiperidin-4-carboxylate (1) was synthesized by the reaction of tosyl chloride (a) with ethyl isonipecotate (b) under mild basic conditions. Compound 1 was subjected to nucleophillic substitution by hydrazine to synthesize 1-tosylpiperidin-4-carbohydrazide (2). The compound, 5-(1-tosylpiperidin-4-yl)-1,3,4-oxadiazole-2-thiol (3) was synthesized by intermolecular cyclization of compound 2 by CS2 under strong basic conditions. The target compounds, 6a-l, were finally synthesized from 3 by reacting with different electrophiles, 5a-l, in an aprotic polar solvent with sodium hydride as an activator. The different propanamoyl electrophiles, 5a-l, were synthesized by the reaction of different aromatic and aliphatic amines, 4a-l, with 3-bromopropionyl chloride under mild basic conditions. The structural elucidation was carried out using modern spectroscopic techniques including IR, 1H-NMR and EI-MS. The antibacterial potential of synthesized compounds was assessed against five bacterial strains. Compounds 6a, 6c, 6d, 6e and 6f were found to be potent antibacterial agents.

Matched MeSH terms: Solvents
Fulltext Continuous-flow Heck synthesis of 4-methoxybiphenyl and methyl 4-methoxycinnamate in supercritical carbon dioxide expanded solvent solutions

Lau PL, Allen RW, Styring P

Beilstein J Org Chem, 2013;9:2886-97.
PMID: 24367454 DOI: 10.3762/bjoc.9.325

The palladium metal catalysed Heck reaction of 4-iodoanisole with styrene or methyl acrylate has been studied in a continuous plug flow reactor (PFR) using supercritical carbon dioxide (scCO2) as the solvent, with THF and methanol as modifiers. The catalyst was 2% palladium on silica and the base was diisopropylethylamine due to its solubility in the reaction solvent. No phosphine co-catalysts were used so the work-up procedure was simplified and the green credentials of the reaction were enhanced. The reactions were studied as a function of temperature, pressure and flow rate and in the case of the reaction with styrene compared against a standard, stirred autoclave reaction. Conversion was determined and, in the case of the reaction with styrene, the isomeric product distribution was monitored by GC. In the case of the reaction with methyl acrylate the reactor was scaled from a 1.0 mm to 3.9 mm internal diameter and the conversion and turnover frequency determined. The results show that the Heck reaction can be effectively performed in scCO2 under continuous flow conditions with a palladium metal, phosphine-free catalyst, but care must be taken when selecting the reaction temperature in order to ensure the appropriate isomer distribution is achieved. Higher reaction temperatures were found to enhance formation of the branched terminal alkene isomer as opposed to the linear trans-isomer.

Matched MeSH terms: Solvents
Fulltext Agarwood branch ethanolic extract: optimal extraction process conditions and cytotoxic effects

Phirdaous Abbas, Yumi Zuhanis Has-Yun Hashim, Hamzah Mohd Salleh, Saripah Salbiah Syed Abdul Azzizz

Biological and Natural Resources Engineering Journal, 2020;3(2):7-26.
MyJurnal

Uninfected agarwood branch is readily available as raw material in agarwood plantation as new practices of agarwood plantation scheme were opted as substitute to the endangered wild type agarwood. The uninfected branch can be easily obtained during pruning process (one of plantation’s common maintenance procedure), throughout the years before inoculation stage. This current study aimed to investigate the optimal extraction process conditions of agarwood branch using ethanol as solvent system for maximal yield, and assess its cytotoxic effects towards MCF-7 breast cancer cells. Uninfected branch of Aquilaria subintegra was subjected to One Factor at a Time (OFAT) and Response Surface Methodology (RSM)-guided ethanolic extraction to achieve maximal yield. The extract was then subjected to cytotoxicity, cell attachment and cell viability assays, respectively. Optimization Run 2 (temperature 45 °C, solid-liquid ratio of 1:30, 16 hours maceration) gave the highest agarwood branch ethanolic extract (ABEE) yield of 44.70 ± 18.9 mg/g dried material (DM). Meanwhile Run 7 (temperature 45 °C, solid-liquid ratio of 1:10, 16 hours of maceration) gave the lowest yield (19.34 ± 14.1 mg/g DM). However, while maintaining the 16 hour-maceration, the model predicted a slightly lower yield of 30.232 ± 0.266 mg/g DM of ABEE with process conditions of 45 °C and solid-liquid ratio of 1:19 when the desirable parameters were factored in namely using (ⅰ) the most suitable temperature (that does not risk the bioactivities of the extract), and (ⅱ) an economical volume of solvent. Crude ABEE obtained from the optimal process conditions resulted in cytotoxicity effects on MCF-7 breast cancer cells with IC50 estimate of 3.645 ± 0.099 μg/mL. The extract also affected MCF-7 cell attachment and viability with altered morphology. More work to elucidate the mechanism of actions of the extract are warranted; which could further lead to development of breast cancer natural product-based therapeutics.

Matched MeSH terms: Solvents
Fulltext Arene diazonium saccharin intermediates: a greener and cost-effective alternative method for the preparation of aryl iodide

Zaharani L, Ghaffari Khaligh N, Shahnavaz Z, Rafie Johan M

Turk J Chem, 2020;44(3):535-542.
PMID: 33488175 DOI: 10.3906/kim-2002-26

In the current protocol, the arene diazonium saccharin derivatives were initially produced from various substituted aromatic amines; subsequently, these intermediates were treated with a greener organic iodide for the preparation of the aryl iodide. We tried to choose low-cost, commercially available, biodegradable, recoverable, ecofriendly, and safe reagents and solvents. The arene diazonium saccharin intermediates could be stored in the liquid phase into a refrigerator for a long time with no significant loss activity. The outstanding merits of the current protocol (a) included the partial recovering of saccharin and tetraethylammonium salt, (b) reduce the use of solvents and the reaction steps due to eliminating separation and purification of intermediates, (c) good yield of the sterically hindered substrates, and (d) avoid the generation of heavy metal or corrosive waste.

Matched MeSH terms: Solvents
Fulltext Antioxidant and LC-QToF-MS/MS analysis of polyphenols in polar and non-polar extracts from Strobilanthes crispus and Clinacanthus nutans

Tan, H. M., Leong, K. H., Song, J., Mohd Sufian, N. S. F., Mohd Hazli, U. H. A., Chew, L. Y., et al.

International Food Research Journal, 2020;27(5):903-914.
MyJurnal

Strobilanthes crispus and Clinacanthus nutans are popular herbal plants in the Southeast
Asian region. The present work was aimed at determining the antioxidant activities and the
associated components in the leaf extracts of both species using polar and non-polar solvents
namely water, methanol, ethyl acetate, and hexane. The total phenolic content (TPC) and total
flavonoid content (TFC) were higher in the leaf extracts of S. crispus as compared to C.
nutans. Among the solvents, methanol was the best solvent in extracting the antioxidant
components for S. crispus (TPC: 159.85 ± 0.89 mg GAE/g extract and TFC: 955.47 ± 2.66 mg
RE/g extract). However, for C. nutans, its methanolic extract yielded the highest TPC (36.39
± 0.17 mg GAE/g extract), whereas ethyl acetate yielded the highest TFC (229.61 ± 7.81 mg
RE/g extract). The high levels of both TPC and TFC contributed to the antioxidant activities
of S. crispus extract as reflected in the methanolic extract attaining the highest level of
antioxidant activities, measured by ferric reducing antioxidant power (FRAP) (6.84 ± 1.12
mmol Fe2+/g extract), DPPH radical scavenging (IC50: 203.60 ± 7.28 μg/mL), and Trolox
equivalent antioxidant capacity (TEAC) (1.01 ± 0.01 mmol TE/g extract) assays. This
contrasted with C. nutans which showed lower antioxidant activities owing to its lower TPC
and TFC. Correlation analysis revealed significant correlations (p < 0.05, r = 0.915 - 0.985)
between both TPC and TFC in S. crispus and antioxidant activities. However, only TPC of C.
nutans showed a significant correlation with FRAP values (r = 0.934). Further tentative
identification of the constituents in the extracts using HPLC-ESI-QToF-MS/MS revealed the
existence of 20 polyphenolic compounds in both S. crispus and C. nutans, which were likely
responsible for their antioxidant activities. In addition, 15 polyphenolic compounds classified
as chalcones, isoflavanoids, flavones, and flavonols have not been previously reported in both
species. The methanolic extracts of both species yielded a higher content of antioxidants, with
S. crispus offering a richer source of dietary antioxidants as compared to C. nutans. However,
further study is needed to identify their bioactivities in relation to their bioactive components.

Matched MeSH terms: Solvents
A current overview of the oxidative desulfurization of fuels utilizing heat and solar light: from materials design to catalysis for clean energy

Lim XB, Ong WJ

Nanoscale Horiz, 2021 May 21.
PMID: 34018529 DOI: 10.1039/d1nh00127b

The ceaseless increase of pollution cases due to the tremendous consumption of fossil fuels has steered the world towards an environmental crisis and necessitated urgency to curtail noxious sulfur oxide emissions. Since the world is moving toward green chemistry, a fuel desulfurization process driven by clean technology is of paramount significance in the field of environmental remediation. Among the novel desulfurization techniques, the oxidative desulfurization (ODS) process has been intensively studied and is highlighted as the rising star to effectuate sulfur-free fuels due to its mild reaction conditions and remarkable desulfurization performances in the past decade. This critical review emphasizes the latest advances in thermal catalytic ODS and photocatalytic ODS related to the design and synthesis routes of myriad materials. This encompasses the engineering of metal oxides, ionic liquids, deep eutectic solvents, polyoxometalates, metal-organic frameworks, metal-free materials and their hybrids in the customization of advantageous properties in terms of morphology, topography, composition and electronic states. The essential connection between catalyst characteristics and performances in ODS will be critically discussed along with corresponding reaction mechanisms to provide thorough insight for shaping future research directions. The impacts of oxidant type, solvent type, temperature and other pivotal factors on the effectiveness of ODS are outlined. Finally, a summary of confronted challenges and future outlooks in the journey to ODS application is presented.

Matched MeSH terms: Solvents
Fulltext DISPERSIVE LIQUID-LIQUID MICROEXTRACTION FOR THE EXTRACTION OF POLYCYCLIC AROMATIC HYDROCARBONS IN APPLE JUICE

LIANG SUN TAN, SAW HONG LOH

UMT Journal of Undergraduate Research, 2020;2(2):15-22.
MyJurnal

Polycyclic aromatic hydrocarbons (PAHs) are hazardous and persistent organic pollutants that usually exist at low concentrations in the environment. In this study, dispersive liquid-liquid microextraction (DLLME) technique coupled with high performance liquid chromatography-fluorescence detection (HPLC-FD) was optimized for the analysis of selected PAHs, namely phenanthrene (PHE), fluoranthene (FLA) and benzo[a]pyrene (BaP) in apple juice. Under the optimal extraction conditions (the mixture of 200 µL of acetone and 50 µL of 1-octanol was applied to extract the selected PAHs for 1 min), the DLLME-HPLC-FD showed excellent linearity over the concentration range of 5 to 200 µg/L for both PHE and FLA, and 0.01 to 5 µg/L for BaP with correlation coefficients, r ≥ 0.9956. The method offered ultra-trace detection of selected PAHs in the range of 0.002 to 0.5 µg/L, and negligible matrix effects in determining selected PAHs with relative recovery average within the range of 92.6 to 109.6% in apple juice. The advantages of applying this method for the extraction of PAHs include rapidity, simple operation, as well as small consumption of organic extraction solvent, which is beneficial for routine analysis.

Matched MeSH terms: Solvents

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