Ketone Extraction Research Articles

Dispersive liquid-liquid microextraction coupled with gas chromatography-mass spectrometry (GC-MS) for the determination of soy sauce aroma compounds

In the present work, a dispersive liquid-liquid microextraction (DLLME) method combined with gas chromatography-mass spectrometry (GC-MS) was successfully developed for accurate determination of aroma-active components in soy sauce. Several key experimental parameters were optimized, including the type of dispersant, vortex time and the volume ratio of extractant and dispersant. The optimal conditions were 1200 μL acetone as dispersant, 800 μL dichloromethane as extractant and 3 min of vortex mixing. The proposed method was validated, achieving good linearities with R2 ≥ 0.9941, recoveries between 82 and 129% with 4-hydroxy-2,5-dimethyl-3(2H)-furanone (HDMF) and 4-hydroxy-2 (or 5)-ethly-5 (or 2)-methyl-3(2H)-furanone (HEMF) within 84–103%, relative standard deviations ranging from 0.02 to 8.60% with HDMF and HEMF between 0.26 and 1.44%, and limits of detection and limits of quantification in the range of 0.08–35.95 μg/L and 0.25–119.83 μg/L, respectively. The entire sample processing with DLLME was completed in roughly 15 min with a total consumption of 2 mL of organic solvent, and 93 volatiles identified in the obtained extracts, with 87.1% (81 volatiles) showing relative standard deviations lower than 10%. Compared to conventional liquid-liquid extraction (LLE), DLLME exhibited obvious advantages of simplicity, rapidity, stability and low solvent consumption, favouring the extraction of acids and ketones. This is the first application of the DLLME technique for the analysis of aroma compounds in soy sauce and is suitable for rapid determination of key aroma compounds like HDMF and HEMF, especially for routine detection and large batch analysis of soy sauce, which can provide reliable information for soy sauce flavour analysis.

Ketone ester supplementation suppresses cardiac inflammation and improves cardiac energetics in a swine model of acute myocardial infarction

BackgroundMyocardial infarction (MI) is a major risk factor for the development of heart failure with reduce ejection fraction (HFrEF). While previous studies have focused on HFrEF, the cardiovascular effects of ketone bodies in acute MI are unclear. We examined the effects of oral ketone supplementation as a potential treatment strategy in a swine acute MI model. MethodsFarm pigs underwent percutaneous balloon occlusion of the LAD for 80 min followed by 72 h reperfusion period. Oral ketone ester or vehicle was administered during reperfusion and continued during the follow-up period. ResultsOral KE supplementation induced ketonemia 2–3 mmol/l within 30 min after ingestion. KE increased ketone (βHB) extraction in healthy hearts without affecting glucose and fatty acid (FA) consumption. During reperfusion, the MI hearts consumed less FA with no change in glucose consumption, whereas hearts from MI-KE-fed animals consumed more βHB and FA, as well as improved myocardial ATP production. A significant elevation of infarct T2 values indicative of inflammation was found only in untreated MI group compared to sham. Concordantly, cardiac expression of inflammatory markers, oxidative stress, and apoptosis were reduced by KE. RNA-seq analysis identified differentially expressed genes related to mitochondrial energy metabolism and inflammation. ConclusionsOral KE supplementation induced ketosis and enhanced myocardial βHB extraction in both healthy and infarcted hearts. Acute oral supplementation with KE favorably altered cardiac substrate uptake and utilization, improved cardiac ATP levels, and reduced cardiac inflammation following MI.

Process optimization and extraction of acids, syringols, guaiacols, phenols and ketones from beech wood slow pyrolysis liquids with supercritical carbon dioxide at different densities

In order to enhance the usability of beech wood slow pyrolysis liquid, an optimization of the extraction process with supercritical carbon dioxide (scCO2) has been carried out. The main goals were to minimize losses and to stabilize the extraction parameters. Different designs of extraction vessels were used to accelerate the extraction and to facilitate the extraction of slow pyrolysis liquids on silica gel as well as in its liquid state. The slow pyrolysis liquid was extracted at different scCO2 densities and temperatures. The densities were approx. 355 and 725 kg/m3 at 313.15 and 333.15 K respectively. A high density is the primary factor in increasing the extraction yield. An elevated temperature at high density level further increased the yields. The distribution of GC-MS detectable compounds of the extracts changed distinctly, resulting in an increase of syringols and a decrease of acids, ketones and furans during extraction.

A Review on “Anjan” Hardwickia binata Roxb: Its Phytochemical Studies, Traditional uses and Pharmacological activities

Hardwickia binata commonly known as “Anjan” belonging to the family Caesalpiniaceae is a handsome medium or large deciduous ornament tree with graceful drooping branch lets is represented by a single species Hardwickia binata Roxb. It is used in folklore medicines for various ailments including diarrhea, leprosy, worm’s infection, indigestion, leucorrhoea, chronic cystitis, gonorrhea, cancer, gram negative and gram positive bacteria and fungi. The parts of plant used as roots, leaves, bark, seed, wood, Husk. The review describes therapeutic efficacy of the leaves, seed, root, husk and its extracts and isolated compounds in different aliments such as antimicrobial, analgesic, antifungal, antibacterial, cardio protective, anti-inflammatory, antitumor and DNA polymerase β inhibition properties of Hardwickia binata were reported. A preliminary Phytochemical screening show that it comprises mainly phenolic compound, saponins, flavonoids, glycosides and tannins, carbohydrate, protein, amino acids, steroids, lipids, quinones, volatile oil, fats and fixed oil. Bioactivity-guided fractionation of an active methyl ethyl ketone extract of Hardwickia binata reported to the isolation of a potent inhibitor, named as Harbinaticacid, a novel diterpenoid and its potency as DNA polymerase β inhibitor. Root bark exudates has been traditionally used to cure breast cancer by Malayali tribes of Chitteri hills. The ethanolic leaf extracts of Hardwickia binata Roxb (Caesalpinaceae) showed a broad-spectrum of activity against both gram-positive and gram-negative bacteria and were screened for antibacterial activity. This systematic review aims to provide information regarding distribution, Morphology, Phytochemical Constituents, Traditional uses and also describes various pharmacological activities reported on the plant Hardwickia binata which may help in future research to improve human health care.

Abraham model correlations for describing the partition of organic compounds from water into the methyl ethyl ketone extraction solvent

ABSTRACT Experimental water-to-methyl ethyl ketone partition coefficients have been determined for 34 different organic solutes at ambient room temperature based on gas–liquid chromatographic measurements. Updated Abraham model correlations were determined for describing solute transfer into methyl ethyl ketone by combining the measured partition coefficient data determined in the present study with published experimental values taken from chemical and engineering literature. Experimental data for 48 compounds were used in determining the revised Abraham model correlations. The revised mathematical correlations were determined to back-calculate the observed partition coefficient data to within an overall average standard deviation of 0.17 log units or less. The partitioning characteristics of the water-to-methyl ethyl ketone system are compared to the characteristics of two other biphasic water-to-ketone partitioning systems.

Rebuttal from Manoja K. Brahma, Adam R. Wende and Kyle S. McCommis.

Drs Karwi and Lopaschuk have provided compelling evidence of the potential for ketone bodies to provide an extra source of ATP for the heart. The foundation of our opposing views most likely stems from comparing analyses of the acute effects of ketone bodies in predominantly ex vivo studies to that which occurs in vivo with more chronic ketosis. Likewise, we must all be more prudent when comparing cardiac metabolic adaptations to physiological ketosis to those observed with ‘pure’ ketosis as occurs with consumption of ketone esters or salts, or ketone infusion. In physiological states of ketosis such as fasting or consumption of a low-carbohydrate, high-fat ketogenic diet, hearts preferentially downregulate ketolytic enzymes, decreasing ketone oxidation and enhancing fatty acid oxidation (Wentz et al. 2010; McCommis et al. 2020). This downregulation of ketolytic enzymes also occurs in the hearts of diabetic mice, or in hearts overexpressing glucose transporter 4 with enhanced glucose uptake and utilization (Brahma et al. 2020). However, cardiac ketone metabolism may be directly enhanced if delivery of lipids or glucose is not concurrently elevated. Recent studies suggest that ketone ester supplementation enhanced cardiac ketone uptake in humans (Monzo et al. 2020), and ketone ester-enriched diets increased the expression of ketolytic enzymes in the rat heart (Yurista et al. 2020). These studies imply that elevated ketone extraction is associated with increased oxidation, but neither of these studies directly measured oxidation. We agree that ketone utilization appears to be more important in failing hearts. Failing hearts from humans and rodent models display enhanced expression of the ketolytic enzymes β-hydroxybutyrate dehydrogenase 1 (BDH1) and succinyl-CoA:3-oxoacid CoA transferase (SCOT) and have been shown to extract more ketones than non-failing hearts (Aubert et al. 2016; Bedi et al. 2016; Horton et al. 2019; Monzo et al. 2020; Murashige et al. 2020). Also, cardiac-specific deletion of BDH1 or SCOT in mice exacerbates cardiac dysfunction and remodelling when challenged by pressure overload (Schugar et al. 2014; Horton et al. 2019). But these knockout mouse models provide perhaps the most significant evidence that ketone body metabolism is not critical for normal hearts, as deletion of BDH1 or SCOT does not directly induce cardiac dysfunction, and these hearts can even normally adapt to physiological ketosis (Schugar et al. 2014; Horton et al. 2019). To conclude, further investigation is needed to better understand the importance of ketone body metabolism in heart failure, as well as in response to ketosis as a potential therapy for heart failure. Readers are invited to give their views on this and the accompanying CrossTalk articles in this issue by submitting a brief (250 word) comment. Comments may be submitted up to 6 weeks after publication of the article, at which point the discussion will close and the CrossTalk authors will be invited to submit a ‘Last Word’. Please email your comment, including a title and a declaration of interest, to [email protected]. Comments will be moderated and accepted comments will be published online only as ‘supporting information’ to the original debate articles once discussion has closed. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article. None. All authors conceived, wrote, and edited this manuscript. All authors have read and approved the final version of this manuscript and agree to be accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved. All persons designated as authors qualify for authorship, and all those who qualify for authorship are listed. A.R.W. is supported by NIH R01 HL133011. K.S.M. is supported by NIH R00 HL136658.

Phytotoxic and Enzymatic Study of Philodendron meridionale on seeds of Lactuca sativa L.

In an effort to identify novel biopesticides, the present study aimed to assess the effects of Philodendron meridionale (Buturi & Sakur) stem and leaf ketonic and ethanolic extracts (SKE, SEE, LKE, and LEE, respectively) on the germination, growth, root respiration, and enzymatic activities of Lactuca sativa L. seeds, and to measure the associated saponins, phenolics, and flavonoids that may possess herbicidal, pharmaceutical, or pesticidal activities. The extracts were obtained using a modified Soxhlet apparatus and methanolic extracts of 0.1, 0.25, 0.5, 0.75 and 1.0 mg.mL-1 were tested, with water and methanol as a control. The presence of saponins and the concentration of phenolic compounds were determined. Allelopathic activity was evaluated in tests of germination, growth, cellular respiration and enzymatic activity. The presence of saponins and the concentration of phenolic compounds equivalent to 225.12 for LKE, 240.45 for LEE, 193.28 for SKE, and 265.14 for SEE (mg·g-1.gallic acid), and flavonoids 52.74 for LKE, 54.31 for LEE, 72.74 for SKE, and 67.21 for SEE (mg.g-1.quercetin) were determined. The allelopathy of the P. meridionale extracts against L. sativa was confirmed through negative effects on L. sativa seed germination, radical growth and morphology, dry mass, and the concentrations of α-amylase (EC 3.2.1.1), ascorbate peroxidase (EC 1.11.1.11), catalase (EC 1.11.1.6), and polyphenol oxidase (EC 1.10.3.1). It was likely that the allelopathic action of the P. meridionale extracts was related to its effects on the membrane permeability and oxidative stress of the treated L. sativa seeds. The P. meridionale extracts contained saponins, calcium oxalate crystals, and flavonoids, including phenolic compounds, which are known allelochemicals with herbicidal activities.

Methods for the Extraction of Heme Prosthetic Groups from Hemoproteins.

Hemoproteins are widely researched because they contain redox-active heme prosthetic groups (iron + protoporphyrin IX) that enable them to perform a range of vital functions, acting as enzymes, participants in electron transfer reactions, or gas sensing, carrying, and storage proteins. While the heme prosthetic group is almost always essential for hemoprotein function, it is frequently desirable to remove it from the protein to enable biochemical or protein engineering studies. Obtaining high yields of the apo form of the hemoprotein can be challenging since high heme-protein binding affinities necessitate the use of harsh conditions to remove heme. In this Bio-Protocol, we present three chemical extraction methods that can be used to efficiently remove heme: methyl ethyl ketone extraction, acid-acetone precipitation, and on-column heme extraction. We also present protocols that can be used to quantitate the amount of residual heme bound to the protein after performing the extraction procedures.

Production routes to bio-acetic acid: life cycle assessment

BackgroundSimilar to biofuels, numerous chemicals produced from petroleum resources can also be made from biomass. In this research we investigate cradle to biorefinery exit gate life cycle impacts of producing acetic acid from poplar biomass using a bioconversion process. A key step in developing acetic acid for commercial markets is producing a product with 99.8% purity. This process has been shown to be potentially energy intensive and in this work two distillation and liquid–liquid extraction methods are evaluated to produce glacial bio-acetic acid. Method one uses ethyl acetate for extraction. Method two uses alamine and diisobutyl ketone. Additionally two different options for meeting energy demands at the biorefinery are modeled. Option one involves burning lignin and natural gas onsite to meet heat/steam and electricity demands. Option two uses only natural gas onsite to meet heat/steam demands, purchases electricity from the grid to meet biorefinery needs, and sells lignin from the poplar biomass as a co-product to a coal burning power plant to be co-fired with coal. System expansion is used to account for by-products and co-products for the main life cycle assessment. Allocation assessments are also performed to compare the life cycle tradeoffs of using system expansion, mass allocation, or economic allocation for bio-acetic acid production. Finally, a sensitivity analysis is conducted to determine potential effects of a decrease in the fermentation of glucose to acetic acid.ResultsGlobal warming potential (GWP) and fossil fuel use (FFU) for ethyl acetate extraction range from 1000–2500 kg CO2 eq. and 32–56 GJ per tonne of acetic acid, respectively. Alamine and diisobutyl ketone extraction method GWP and FFU ranges from −370–180 kg CO2 eq. and 15−25 GJ per tonne of acetic acid, respectively.ConclusionsOverall the alamine/diisobutyl ketone extraction method results in lower GWP and FFU values compared to the ethyl acetate extraction method. Only the alamine/diisobutyl extraction method finds GWP and FFU values lower than those of petroleum based acetic acid. For both extraction methods, exporting lignin as a co-product produced larger GWPs and FFU values compared to burning the lignin at the biorefinery.

The partition of organic compounds from water into the methyl isobutyl ketone extraction solvent with updated Abraham model equation

ABSTRACT Experimental water-to-methyl isobutyl ketone partition coefficients have been determined for 27 different organic solutes based on gas chromatographic measurements. Updated Abraham model correlations were determined for describing solute transfer into methyl isobutyl ketone by combining the measured partition coefficient data determined in the present study with published experimental values taken from chemical and engineering literature. One hundred nineteen compounds were used in determining the revised Abraham model correlations. After calculations, the revised mathematical correlations were found to match the experimental data to within an overall average standard deviation of 0.21 log units.

Efficient Fractionation of Corn Stover for Biorefinery Using a Sustainable Pathway

This study presents a sustainable pathway for fractionating corn stover to produce glucose, high-quality lignin nanoparticles (LNPs), and levulinic acid (LA) based on the use of p-toluenesulfonic acid (p-TsOH), a solvent having strong acidity and surface activity at a high concentration. At a moderate pretreatment temperature (100 °C), 85% of xylose, 88% of arabinose, and 83% of lignin were removed from the substrate and present in the hydrolysate, while the cellulose yield in the solid residue fraction was 93%. The cellulose fraction exhibited much reduced “biomass recalcitrance” and was readily enzyme-hydrolyzed, with its glucose yield reaching up to 93% at a high solid concentration of 15% (w/w). The hydrolysate, involving the p-TsOH catalyst, was recycled for further hydrolysis of fresh corn stover: after recycling the hydrolysate four times, the cellulose fraction still had a high glucose yield of 81%. The lignin fraction in the hydrolysate was utilized in the form of LNPs, which were prepared as a result of diluting the recycled hydrolysate. The as-prepared LNPs were spherical and uniform, with an average particle size of 147 nm. The application of LNPs in the preparation of chitosan film significantly improved its strength. After LNP preparation, the diluent containing monomeric sugars was directly heated to 180 °C to produce LA in the presence of p-TsOH (an effective catalyst) with an LA yield of 57.1%. The LA was easily separated from the spent acid based on methyl isobutyl ketone (MIBK) extraction, and the p-TsOH/water mixture was recycled in the process.

Simultaneous extraction and chromatographic separation of n-alkanes and alkenones from glycerol dialkyl glycerol tetraethers via selective Accelerated Solvent Extraction

A method is described for simultaneous extraction and chromatographic separation of saturated hydrocarbons (n-alkanes) and unsaturated long-chain ketones (alkenones) from glycerol dialkyl glycerol tetraethers (GDGTs) using selective accelerated solvent extraction (ASE). We show that the method can be used to successfully separate n-alkanes and alkenones from GDGTs in marine sediment samples and n-alkanes from GDGTs in lake sediments and soil samples. A comparison of our method with analysis of samples purified using classical silica column chromatography demonstrates that the new method does not affect the alkenone unsaturation index (U37K'), the TetraEther indeX (TEX86), the Methane Index (MI), the Ring Index (RI), the branched-GDGT-based paleotemperature and soil pH indices, the Branched and Isoprenoid Tetraether (BIT) index, the n-alkane average chain length (ACL) or the carbon preference index (CPI). The new procedure results in higher sample recoveries for n-alkanes and more precise U37K' estimates at low concentrations, and contributes to reduced analyst laboratory time.

Abstract 562: Comprehensive Arteriovenous Metabolomics in the Human Heart

Introduction: Despite broad interest in the role of metabolism in the pathogenesis of heart failure, a definitive account of fuel use by the beating human heart in situ is lacking. We therefore determined the uptake and release of over 270 metabolites by simultaneous sampling of arterial, coronary sinus, and femoral venous blood in 100 patients. Methods: We enrolled 100 patients (60% male, 12% diabetic, age = 63.6 +/- 13.5 years, BMI = 29.75 +/- 6.1, EF = 57.14 +/- 6.48) undergoing ablation of atrial fibrillation. We used liquid chromatography-mass spectrometry to quantify over 270 metabolites in plasma from coronary sinus, femoral vein, and arterial blood. We also measured O 2 and CO 2 concentration, as well as atrial pressure. Results: We detected uptake or release of 77 metabolites by the heart and 136 metabolites across the leg (p <0.05 after Benjamini-Hochberg correction). We determined the cardiac extraction of all major fuel sources, including 29 fatty acids, 11 amino acids, lactate, acetoacetate, and 3-hydroxybutyrate. Several patterns emerge: first, while the leg extracts glucose (FV/A = 0.95, q = 4.7x10-14) and releases lactate (FV/A = 1.11, q = 2.87x10-14), the heart extracts lactate (CS/A = 0.95, q = 3.77x10-9) and neither extracts nor secretes glucose. Second, while the leg releases nearly all fatty acid and amino acid species, the heart consumes most fatty acids and certain non-essential amino acids. Third, extraction of unsaturated acylcarnitines correlates with left atrial pressure (p<0.01). Finally, we find a significant positive correlation between myocardial O2 consumption and extraction of ketones (p < 0.01), but not other major cardiac fuels. Conclusion: We present the most comprehensive study to date of metabolite use and secretion by the human heart. We find the heart to be an avid consumer of fatty acids and ketone bodies, but less so of glucose and essential amino acids. Consumption of ketones increases with O2 consumption, suggesting that ketones may be a preferential fuel source under high work loads. Extraction of certain acylcarnitines increases with left atrial pressure, indicating metabolic reprogramming under high filling pressures. In summary, we provide the first comprehensive model of fuel use by the beating human heart in situ.

Influence of physicochemical factors on environmental availability and distribution of semiochemicals that affect Varroa destructor and phylogenetically close organisms: classification by VHWOC PCA-clustering

Varroa destructor parasites Apis mellifera larvae following the interception of the semiochemicals involved in bee communication; thus, the semiochemical availability and distribution pathways take place within different physicochemical environments. The structure of 172 molecules with semiochemical activity on Varroa destructor was used to compute the representative physicochemical descriptors of the thermodynamic partition among different physicochemical environments: vapor pressure (V), Henry's coefficient (H), water solubility constant (W), octanol-water partition coefficient (O) and organic carbon partition coefficient (C); VHWOC. The principal component analysis (PCA) and hierarchical clustering of VHWOC descriptors allowed us to establish the trend in availability and distribution of the semiochemicals resulting in a 4 classes model of physicochemical environments: Class 1, Soluble/Volatile; Class 2, Soluble; Class 3, Contact; Class 4, Adsorbed/Volatile. Our results suggest that semiochemicals can transit between different thermodynamic equilibrium phases depending on environment conditions. The classification prediction of the model was tested on 6 new molecules obtained from ketonic extracts of L5 Apis mellifera drone larvae; locating them in class 4, which was consistent with their molecular structure. This study can be the starting point for the design of synthetic semiochemicals or for the control of Varroa destructor. In addition, the method can be used in the analysis of other semiochemical groups.

Isolation and characterization of polyphenols from Euphorbia heterophylla L. (Euphorbiaceae) leaves

Many of Euphorbiaceae species are recognized as traditional medicinal plants and the oils and latex of many species have also economic importance. In fact, Euphorbia heterophylla L., belonging to this family and popularly known in Brazil as “leiteira”, “flor-de-poetas” and wild poinsettia, has been used traditionally in Africa and India to treat many kinds of health disorders. However, the chemical composition of this species has been little studied so far. In the present investigation, the flavonoids quercitrin (quercetin 3-O-α-L-rhamnopyranoside), hyperin (quercetin 3-O-β-D-galactopyranoside), isoquercitrin (quercetin 3-O-β-D-glucopyranoside) and isoquercitrin 6”-malonate (quercetin 3-O-β-D-(6”-malonate)-glucopyranoside) were isolated from an ethyl acetate partition of aqueous ketone extract from E. heterophylla leaves. The dehydroellagitannins geraniin and phyllantusiin D as well as 1,2,3,4,6- penta-O-galloyl- β-D-glucopyranoside, caffeic acid and the coumarin aesculetin (6,7-dihydroxycoumarin) were also isolated. All the compounds were characterized by spectroscopic methods such as 1H and 13C-NMR, COSY, HETCOR, APT and by comparison with literature data. The presence of these substances of relevant bioactivity is reported for the first time in E. heterophylla through our study supporting in this way the medicinal use of this specie.

Urea functionalized surface-bonded sol-gel coating for on-line hyphenation of capillary microextraction with high-performance liquid chromatography

Sol-gel urea functionalized-[bis(hydroxyethyl)amine] terminated polydimethylsiloxane coating was developed for capillary microextraction-high performance liquid chromatographic analysis from aqueous samples. A fused silica capillary is coated from the inside with surface bonded coating material and is created through in-situ sol-gel reaction. The urea-functionalized coating was immobilized to the inner surface of the capillary by the condensation reaction of silanol groups of capillary and sol-solution. The characterization of the coating material was successfully done by using X-ray photoelectron spectroscopy, thermogravimetric analysis, field emission scanning electron microscope, and energy dispersive X-ray spectrometer. To make a setup of online capillary microextraction-high performance liquid chromatography, the urea functionalized capillary was installed in the HPLC manual injection port. The analytes of interest were pre-concentrated in the coated sampling loop, desorbed by the mobile phase, chromatographically separated on C-18 column, and analyzed by UV detector. Sol-gel coated capillaries were used for online extraction and high-performance liquid chromatographic analysis of phenols, ketones, aldehydes, and polyaromatic hydrocarbons. This newly developed coating showed excellent extraction for a variety of analytes ranging from highly polar to non-polar in nature. The analysis using sol-gel coating showed excellent overall sensitivity in terms of lower detection limits (S/N = 3) for the analytes (0.10 ng mL−1–14.29 ng mL−1) with acceptable reproducibility that is less than 12.0%RSD (n = 3). Moreover, the capillary to capillary reproducibility of the analysis was also tested by changing the capillary of the same size. This provided excellent%RSD of less than 10.0% (n = 3).

In vitro action of Mimosa caesalpinifolia ketone extract on Haemonchus contortus and Trichostrongylus colubriformis

This study aimed to evaluate the in vitro anthelmintic activity of Mimosa caesalpinifolia (sabiá) ketone extract, which is rich in condensed tannins (CT), on Haemonchus contortus and Trichostrongylus colubriformis. The leaves and stems of M. caesalpinifolia were collected, dried in the shade, and ground to a dry powder from which ketone extracts were obtained for in vitro assays. The extracts were diluted in 5% acetone and PBS to concentrations in the range 0.25-2.80 mg mL-¹ and the inhibition of egg hatchability was assayed. Feces collected from goats naturally infected with H. contortus (55%) and T. colubriformis (45%) were macerated and the helminth eggs were collected to conduct in vitro egg hatchability tests. Nematode larvae collected from the feces were used for a larval exsheathment inhibition assay of M. caesalpinifolia leaf and M. caesalpinifolia leaf and stem ketone extracts at concentrations of 0.6 and 1.2 mg mL-¹; three replicates were performed for each concentration. PBS was used as a negative control. Polyvinylpolypyrrolidone (PVPP) was added to the extracts to assess the effect of phenolic compounds on anthelmintic activity. An inhibitory effect of 80.7% and 82.3% was observed on hatchability after treatment with 1.0 and 2.0 mg mL-¹ M. caesalpinifolia leaf ketone extract, respectively. An inhibition rate lower than 75% was observed for 1.0 mg mL-¹ M. caesalpinifolia leaf and stem ketone extract. The M. caesalpinifolia leaf ketone extract larval exsheathment assay resulted in inhibition of 97.3% and 99.8% at concentrations of 0.6 and 1.2 mg mL-¹, respectively. For the leaf and stem ketone extract, the larval exsheathment inhibition was 94.3% at 1.2 mg mL-¹. The leaf and leaf and stem extracts showed no inhibitory effects on larval exsheathment after the addition of PVPP. These results showed that cuticular loss was related to the action of the phenolic compounds in the M. caesalpinifolia extracts. M. caesalpinifolia leaf ketone extract inhibited egg hatchability, but the leaf and stem extract showed lower efficiency, which indicated a greater abundance of active compounds in the leaves. The M. caesalpinifolia ketone extracts were effective in the inhibition of larval exsheathment at the highest concentration tested. Based on these results, in vivo studies should be performed to demonstrate the anthelmintic activity of this plant in goats.

DSC characterization of rabbit corneas treated with Stryphnodendron adstringens (Mart.) Coville extracts

Keratoconus is an eye ectasia that affects the cornea causing distortion of vision. Corneal crosslinking promoted by riboflavin photo-stimulated at 365 nm is a treatment used successfully to block the keratoconus progression. In this study, we characterize rabbit corneas subjected to enhanced crosslinking using different vegetable extracts prepared from Stryphnodendron adstringens (Mart.) Coville bark by differential scanning calorimetry. The extracts tested in this study were: aqueous, ketonic, ethanolic, ethyl acetate and hydroalcoholic, which revealed high levels of polyphenols, such as proanthocyanidins. The corneas, obtained from the slaughter rabbits, were divided into groups: control (consisting of untreated corneal samples) and S. adstringens, where the samples were subjected to 4% vegetable extracts for 2 h. The DSC profiles of the corneas were obtained in nitrogen atmosphere. The results showed that temperature and enthalpy of denaturation of the corneal samples treated with S. adstringens were higher than the control group. The control group presents temperature and enthalpy values of 59.8 ± 1.1 °C and 24.6 ± 2.7 J g−1, respectively. After crosslinking with ketone extract, the values were 90.1 ± 1.1 °C and 39.9 ± 2.7 J g−1. These results show that S. adstringens is efficient to increment the crosslinking level of the corneas.

Detailed Componential Characterization of Extractable Species with Organic Solvents from Wheat Straw.

Componential analysis of extractives is important for better understanding the structure and utilization of biomass. In this investigation, wheat straw (WS) was extracted with petroleum ether (PE) and carbon disulfide (CS2) sequentially, to afford extractable fractions EFPE and EFCS2, respectively. Detailed componential analyses of EFPE and EFCS2 were carried out with Fourier transform infrared (FTIR) spectroscopy, gas chromatography/mass spectrometry (GC/MS), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), energy dispersive spectrometry (EDS), and electron probe microanalysis (EPMA). Total extractives were quantified 4.96% by weight compared to the initial WS sample. FTIR and GC/MS analyses results showed that PE was effective for the extraction of ketones and waxes derived compounds; meanwhile CS2 preferred ketones and other species with higher degrees of unsaturation. Steroids were enriched into EFPE and EFCS2 with considerable high relative contents, namely, 64.52% and 79.58%, respectively. XPS analysis showed that most of the C atoms in extractives were contained in the structures of C-C, C-COOR, and C-O. TEM-EDS and EPMA analyses were used to detect trace amount elements, such as Al, Si, P, S, Cl, and Ca atoms. Detailed characterization of extractable species from WS can provide more information on elucidation of extractives in biomass.

Liquid-liquid equilibrium for ternary systems, methyl isobutyl ketone + (catechol, resorcinol and hydroquinone) + water at 333.15 K, 343.15 K and 353.15 K

Liquid-liquid equilibrium (LLE) data are vital to extraction process design and optimization. To provide fundamental data for the extracting process of dihydric phenol from wastewater, experimental liquid equilibrium data for ternary systems {methyl isobutyl ketone + catechol + water}, {methyl isobutyl ketone + resorcinol + water} and {methyl isobutyl ketone + hydroquinone + water} were determined at 333.15 K, 343.15 K and 353.15 K under atmospheric pressure. The NRTL and UNIQUAC models were used to correlate the experimental data and relevant binary interaction parameters were yielded. The experimental data were successfully correlated with the two models, and the root mean square deviations (RMSD) between the calculated and experimental values were less than 2%. Moreover, NRTL model performed slightly better than UNIQUAC model since the RMSD was smaller. Distribution coefficient and selectivity were employed to assess methyl isobutyl ketone's extraction capacity, which indicate that, methyl isobutyl ketone is a desirable extractant with extraction performance and physiochemical properties outperforming other extractants.