Solvents Acetone Research Articles

Determination of four residual solvents in cefepime by headspace gas chromatography

ObjectiveTo establish a headspace gas chromatography method to determine the residual solvents of methanol, acetone, dichloromethane, and toluene in cefepime. MethodsHeadspace gas chromatography using a DB-624 capillary column and temperature program was performed to detect four residual solvents in cefepime. The temperature program consisted of an initial temperature of 60 ℃maintained for 4 min, a temperature increased to 120 ℃ at 20 ℃·min−1 maintained for 3 min, and then a temperature increased to 200 ℃ at 40 ℃·min−1 maintained for 3 min. ResultsLinear relationships were found between the peak areas and mass concentrations of the four solvents mentioned above within the defined ranges. The limits of detection for methanol, acetone, dichloromethane and toluene were 0.50, 0.15, 0.10 and 0.08 mg·L-1, respectively. The recoveries obtained using the standard addition method ranged from 98.41 % to 100.94 %. ConclusionThis method demonstrated high sensitivity and good reproducibility, and it can be used to effectively control the residual amounts of methanol, acetone, dichloromethane, and toluene, to further improve the quality of cefepime.

Two Novel Metformin Carboxylate Salts and the Accidental Discovery of Two 1,3,5-Triazine Antihyperglycemic Agent.

Metformin (MET), commonly marketed as a hydrochloride salt (MET-HCl) for better pharmacokinetic profile over the free base, would release a high concentration of chloride ions and cause adverse gastrointestinal effects. The preparation of chloride-free MET salts could potentially circumvent this issue. In this study, seven carboxylic acids (formic acid, acetic acid, malonic acid, succinic acid, fumaric acid, cinnamic acid, and acetylsalicylic acid) were used for preparing MET carboxylate salts. When compared with MET-HCl, all MET salts/salt hydrates show lower dissolution rates in pH 6.8 phosphate buffer. However, the cinnamic acid and acetylsalicylic acid show significantly higher dissolution rates in the forms of MET salt/salt hydrate. In the permeability test, the permeability of the MET in all of the salts was not improved. However, the permeability of cinnamic acid in the MET cinnamate is reduced, and the permeability of acetylsalicylic acid in the MET acetylsalicylate is increased. Meanwhile, at a higher crystallization temperature, the acetone solvent and a hydrolyzed product of acetylsalicylic acid react with MET respectively, leading to two unexpected 1,3,5-triazine derivatives. The results of in vitro bioactivity assays indicate that one of the triazine molecules promote glucose consumption more effectively than MET-HCl, and had relatively weak lactate production ability at low concentration. This glucose metabolism regulating compound may serve as a novel lead antihyperglycemic agent for further optimization.

Assessment of anticancer properties of cumin seed (Cuminum cyminum) against bone cancer.

Early-life osteosarcoma is associated with severe morbidity and mortality, particularly affecting young children and adults. The present cancer treatment regimen is exceedingly costly, and medications like ifosfamide, doxorubicin, and cisplatin have unneeded negative effects on the body. With the introduction of hyphenated technology to create medications based on plant molecules, the application of ayurvedic medicine as a new dimension (formulation, active ingredients, and nanoparticles) in the modern period is rapidly growing. The primary source of lead compounds for the development of medications for avariety of ailments is plants and their products. Traditionally, Cuminum cyminum (cumin) has been used as medication to treat a variety of illnesses and conditions. The cumin seed was successfully extracted with solvents Hexane, Chloroform, Methanol, Ethanol and Acetone. Following the solvent extraction, the extract residue was assayed in MG63 cells for their anti-proliferative properties. First, we used the [3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide] (MTT) assay to test the extracted residue's cytotoxicity. The results show that hexane extract Half-maximal inhibitory concentration (IC50 86 µG/mL) effciently inhibits cells by causing programmed cell death. Furthermore, using the Acridine orange/ethidium bromide (AO/EB) staining method, the lactate dehydrogenase assay, and the reactive oxygen species assay using the Dichloro-dihydro-fluorescein diacetate (DCHFDA) staining method, we have demonstrated that the hexane extract causes apoptosis in MG63 cells. Furthermore, flow cytometry research revealed that the hexane extract stops the cell cycle in the S phase. In addition, the hexane extract limits colony formation and the migration potential as shown by the scratch wound healing assay. Furthermore, the extract from cumin seeds exhibits remarkable bactericidal properties against infections that are resistant to drugs. Gas chromatography analysis was used to quantitatively determine the hexane and methanolic extract based on the experimental data. The primary chemical components of the extract are revealed by the study, and these help the malignant cells heal. The present study finds that there is scientific validity in using cumin seeds as a novel method of anticancer therapy after undergoing both intrinsic and extrinsic research.

Exploring the potential of a new thermotolerant xylanase from Rasamsonia composticola (XylRc): production using agro-residues, biochemical studies, and application to sugarcane bagasse saccharification.

Xylanases from thermophilic fungi have a wide range of commercial applications in the bioconversion of lignocellulosic materials and biobleaching in the pulp and paper industry. In this study, an endoxylanase from the thermophilic fungus Rasamsonia composticola (XylRc) was produced using waste wheat bran and pretreated sugarcane bagasse (PSB) in solid-state fermentation. The enzyme was purified, biochemically characterized, and used for the saccharification of sugarcane bagasse. XylRc was purified 30.6-fold with a 22% yield. The analysis using sodium dodecyl sulphate-polyacrylamide gel electrophoresis revealed a molecular weight of 53kDa, with optimal temperature and pH values of 80°C and 5.5, respectively. Thin-layer chromatography suggests that the enzyme is an endoxylanase and belongs to the glycoside hydrolase 10 family. The enzyme was stimulated by the presence of K+, Ca2+, Mg2+, and Co2+ and remained stable in the presence of the surfactant Triton X-100. XylRc was also stimulated by organic solvents butanol (113%), ethanol (175%), isopropanol (176%), and acetone (185%). The Km and Vmax values for oat spelt and birchwood xylan were 6.7 ± 0.7mg/mL, 2.3 ± 0.59mg/mL, 446.7 ± 12.7µmol/min/mg, and 173.7 ± 6.5µmol/min/mg, respectively. XylRc was unaffected by different phenolic compounds: ferulic, tannic, cinnamic, benzoic, and coumaric acids at concentrations of 2.5-10mg/mL. The results of saccharification of PSB showed that supplementation of a commercial enzymatic cocktail (Cellic® CTec2) with XylRc (1:1 w/v) led to an increase in the degree of synergism (DS) in total reducing sugar (1.28) and glucose released (1.05) compared to the control (Cellic® HTec2). In summary, XylRc demonstrated significant potential for applications in lignocellulosic biomass hydrolysis, making it an attractive alternative for producing xylooligosaccharides and xylose, which can serve as precursors for biofuel production.

Evaluation of Fatigue and Impacted bond Strengths of Denture Base Repaired by Using Different Type of Surface Treatment

Objective: Since the 1930s, a variety of resins have been introduced into dental treatments for the construction of dental prostheses and their efficacy has been based on physical, chemical and biological properties. Denture breakage is usually related to faulty design, faulty fabrication, and/or poor materials choice. Purpose: of this study is to investigate (in vitro) the fatigue bond strength and impact bond strength of the denture repaired by light-cured acrylic resins by using different chemical solvents such as acetone, monomer and thiner. Materials and methods: The acrylic resin used are heat-cure, specially designed molds are use to prepare 6 groups of specimens following the manufacturer's instruction (5 specimens for each cured polymerization). Specimens were cut in guiding by standardized positional jig. The ends of specimen saturated by different solvents acetone, thiner and monomer before repairing. To evaluate the impact strength, plastic strips were fabricated as per the dimensions (50×5×4) mm. Alternating bending fatigue machine was used to test the ten samples with the dimension of (70102.5) mm. Result: impact bond strength with monomer solvent higher than thiner solvent and acetone solvent. Fatigue bond strength with acetone solvent higher than thiner solvent and monomer solvent. Acetone, thiner and monomer were applied as solvents, the results of all surface treatments revealed significant difference at (P- value <0.05) in mean value (no significant for fatigue bonde strength but significant with impact bond strength.

Synthesis, Structure, and Hirshfeld Surface Analysis of tetrakis(N,N’-diethylthiourea)bis(isothiocyanato)nickel

The complex compound tetrakis(N,N’-diethylthiourea)bis(isothiocyanato)nickel or [Ni(detu)4(NCS)2] (denoted as UMCC-1) has been synthesized by reflux method in two different solvents namely acetone and methanol. This study aims to synthesize, characterize, and analyze the Hirshfeld Surface complex UMCC-1, which was obtained using the reflux method with the mole ratio of NiCl2: detu: KSCN is 1:2:4. Single crystals UMCC-1 in acetone and methanol are dark green in color with melting points of 135-137°C and conductivity of 66.4-84.4 µS. The FTIR absorption band analysis of the two crystals is very similar, ν(C S) detu 590 cm−1 and ν(C≡N) isothiocyanate 2119 cm−1. The refinement of the crystal structure from the single crystal XRD data shows that the two dark green crystals are a molecular type that has a distorted octahedral geometry with the same crystal lattice, monoclinic crystal lattice, P21/c1 space group (no.14), crystal lattice parameter a= 11.112(3) Å, b= 17.249(5) Å, c= 9.647(3) Å, and β= 100.785(10). However, the complex produced in acetone solvent has better refinement quality than methanol concerning %R= 3.27 and %R = 4.55, respectively. The UMCC-1 crystal shows intermolecular hydrogen bonds N-H---S(isothiocyanato) and intramolecular hydrogen bonds N-H---S(detu) with Hirshfeld Surface analysis showing a significant contribution of H---H (69.5%) on crystal packing.

Synthesis, crystal structures, spectroscopy, and quantum chemical studies on the 4-dimethylaminopyridinium-2,4-dinitrophenolate: an organic NLO material for optoelectronics.

In this work, the 4-dimethylaminopyridinium-2,4-dinitrophenolate (4DMAP + 2,4DNP) by slow evaporation solution growth method has been presented. The Fourier transform infrared (FT-IR) (4000-400cm-1) and FT-Raman (4000-50cm-1) spectra were recorded for the grown crystal. The computational calculation has been carried out with density functional theory (DFT) in ground state with Gaussian program package. Optimized geometrical parameters (bond distances, bond angles, and dihedral angles) have been obtained and compared with X-ray crystallography data. The calculated fundamental vibrational frequencies from DFT/B3LYP with 6-311 + + G(d,p) level of theory were scaled so as to agree with the observed results, and the scaling factors were reported. Experimental and computed ultraviolet-visible (UV-Vis) spectra in acetone and methanol solvents were found comparable to each other. Furthermore, the frontier molecular orbitals (FMOs) energies, molecular electrostatic potential (MEP), nonlinear optical (NLO), hirshfeld surface (HS), and global chemical descriptors of the molecule were also calculated. The thermal stability and the melting point of the title compound were analyzed by the thermogravimetric analysis/differential thermal analysis (TGA/DTA) techniques. The mechanical behavior of the organic single crystal was measured by Vickers micro-hardness method. The third-order nonlinear optical properties such as nonlinear refractive index (n2), nonlinear absorption coefficient (β), optical nonlinear susceptibility Reχ(3), and optical nonlinear susceptibility Imχ(3) were calculated by using the open and closed aperture Z-scan technique. The theoretical and experimental NLO values clearly proposed that the nonlinearity of 4DMAP + 2,4DNP molecule could be helped as a potential candidate for optical limiting, frequency doubling, and optical switching applications.

Enhanced Extraction of Carotenoids from Tomato Industry Waste Using Menthol/Fatty Acid Deep Eutectic Solvent

This study aimed to explore the efficiency of hydrophobic deep eutectic solvents (HDESs) composed of menthol and fatty acids for extracting carotenoids from tomato by-products. A selection of nine different HDESs and fatty acid mixtures were prepared and evaluated for their carotenoid extraction potential. The highest extraction yield was obtained with menthol/hexanoic acid 2:1 (94.5 ± 3.3 μg CtE/g dm), demonstrating the influence of the specific composition of DES components on extraction efficiency. An optimization process employing a Box–Behnken design was conducted to identify the optimal extraction conditions. The solvent-to-solid ratio, extraction time, and temperature were studied, resulting in an extraction yield increase of up to 48.5% under optimized conditions (solvent-to-solid ratio of 25:1, extraction time of 90 min, and temperature of 50 °C). Furthermore, potent antioxidant properties, including antiradical activity (63.7 ± 4 μmol AAE/g dm) and reducing power (26.7 ± 1.8 μmol AAE/g dm), were recorded. Comparative analyses with conventional organic solvents (hexane, ethyl acetate, and acetone) highlighted the superiority of HDES in both carotenoid extraction and antioxidant capacity. A color analysis of the extracts showed distinctive color profiles, with the HDES extract displaying higher redness and reduced yellowness compared to organic solvent extracts. Principal component analysis (PCA) and multivariate correlation analysis (MCA) revealed strong correlations between total carotenoid content and antioxidant parameters, underscoring the relationship between carotenoid extraction and antioxidant potential. In conclusion, this study highlights the potential of HDESs, particularly Men/Hex 2:1, as efficient and sustainable solvents for carotenoid extraction. These findings offer valuable insights for the development of innovative and environmentally friendly methods for extracting carotenoids with potential applications in various industries.

Novel method for the prediction of distribution and elution characteristic of several drugs in cellulose diacetate-water system: Interaction between mixed solvent and cellulose diacetate

Drug-loaded cellulose diacetate (CDA) membranes were prepared by dissolving cellulose diacetate in a mixed solvent of acetone and ethanol, adding the drug to it, pouring it on a glass plate and evaporating the solvent. In this study, it was prepared CDA membranes varying composition of the mixed solvent (the mass ratio of acetone (ACE) to ethanol (EtOH)) and investigated their microstructure and performance.The release properties of drugs in drug-loaded CDA membranes were examined in correlation with the composition of the mixed solvent and a method to be able to predict the release properties of drugs was proposed. Penicillin G potassium, streptomycin sulfate and ampicillin were used as drugs. The microstructure of the membranes was determined using SEM analysis and the release properties of drugs were measured using spectrofluorophotometer. It was shown that the composition of the mixed solvent can have a significant effect on the overall performance of CDA membrane. The intrinsic viscosity measurements and solubility parameter analysis proved that the intrinsic viscosity of CDA in polymer solutions with mixed solvents and the solubility parameter difference (Δδ) between mixed solvents and CDA were relative with the release properties of drugs. The release rates of drugs from the membrane related to △δ directly and the intrinsic viscosity inversely. Therefore, the release rates of drugs from CDA membrane can be controlled by changing the composition of the solvent used for the preparation of the polymer membrane.

Toward well-defined colloidal particles: Efficient fractionation of lignin by a multi-solvent strategy

Colloidal lignin particles (CLPs) have sparked various intriguing insights toward bio-polymeric materials and triggered many lignin-featured innovative applications. Here, we report a multi-solvent sequential fractionation methodology integrating green solvents of acetone, 1-butanol, and ethanol to fractionate industrial lignin for CLPs fabrication. Through a rationally designed fractionation strategy, multigrade lignin fractions with variable hydroxyl group contents, molecular weights, and high purity were obtained without altering their original chemical structures. CLPs with well-defined morphology, narrow size distribution, excellent thermal stability, and long-term colloidal stability can be obtained by rational selection of lignin fractions. We further elucidated that trace elements (S, N) were reorganized onto the near-surface area of CLPs from lignin fractions during the formation process in the form of -SO42− and -NH2. This work provides a sustainable and efficient strategy for refining industrial lignin into high-quality fractions and an in-depth insight into the CLPs formation process, holding great promise for enriching the existing libraries of colloidal materials.

Novel jellyfish-shaped resorcin[4]arene macrocyclic cocrystal via collaboration of macrocyclic chemistry and co-crystal engineering: Insight into structural, noncovalent interactions and computational chemistry

The collaboration of macrocyclic chemistry and co-crystal engineering has witnessed rapid development in recent years for the creation of functional solid-state. Here, we report the construction of novel jellyfish-like co-crystal derived from macrocyclic resorcin[4]arenes (R4A) serving as a bell and (Z)-3-(pyridine-4-yl)-2-(4-(pyridine-4-yl)phenyl)acrylonitrile (PPPA) molecules acting as a tentacle through the precise engineering of supramolecular interactions. The co-crystal structure was comprehensively investigated using single crystal X-ray diffraction (SXRD), X-ray powder diffraction (XRD), Infrared spectroscopy (IR) and molecular modeling. The packing pattern of the co-crystal structure shows the inclusion-of acetone solvent that connects the neighboring R4A cavitands into high order linear structure stabilized by multiple C–H⋯O, hydrogen bonds and C–H⋯π interactions. Interestingly, jellyfish like architecture is obtained by the interaction of PPPA with R4A molecules through collaborative C–H⋯O, CH⋯N and OH⋯N Hydrogen bonds. Additionally, the HOMO-LUMO, molecular electrostatic potential (MESP), Interaction region indicator (IRI) analysis, and Localized orbital locator (LOL) were collectively employed to provide comprehensive insights into the electronic structure and reactivity of the studied compound. Hirshfeld surface analysis in combination with 2D fingerprints plots were carried out to get insight into the role of various non-covalent routs in the formation cocrystal packing. This strategy will guide any future synthetic endeavors aimed at engineering supramolecular interactions on demand using macrocycle chemistry and co-crystal engineering for the development of promising novel functional materials.

Evaluation of antioxidant and anti-tyrosinase activities of surfactant and alcohol extracted Combretum Indicum leaves

Combretum Indicum (CI), which contains numerous bioactive compounds, has been used in traditional medicine for a variety of reasons, including the treatment of skin conditions. This study investigates the antioxidant and anti-tyrosinase activities of CI leaves extracted using different surfactants (Triton X-100 and Vitamin E TPGS) at concentrations of 1%, 2%, and 3%, as well as various alcohol solvents (acetone, methanol, and ethanol) at concentrations of 50%, 70%, and 90%. The antioxidant activity of the extracts has been evaluated using Total Phenolic Content (TPC) and 2,2-diphenyl-1-picrylhydrazyl (DPPH), while the anti-tyrosinase activity was assessed through a mushroom tyrosinase inhibition assay. Prior to analysis, CI leaves had been macerated, extracted, and freeze-dried. The research established that ethanol at a concentration of 50% is the optimum solvent to extract CI leaves, as it demonstrated good antioxidant and anti-tyrosinase action with a high percentage of yield and total phenolic content. As a result, the outcomes of this study contribute to a better understanding of the potential applications of CI leaf extract in cosmetics, notably in the treatment of oxidative stress and hyperpigmentation. Further study and development in this field could lead to the creation of effective and natural cosmetic products produced from CI leaves that have antioxidant and anti-tyrosinase effects.

Synthesis of Methyl Cellulose from Rice Husk Cellulose (Oryza sativa L.) with Methylene Chloride Through Etherification Reaction

Methyl cellulose is synthesized by an etherification reaction between α-cellulose created by isolating rice husks (Oryza sativa L.) with methylene chloride. Methylcellulose synthesis is performed by combining 1 g α-cellulose with acetone solvents at variations of methylene chloride 6 g, 8 g, 10 g, 12 g, and 14 g for 6 hours, resulting in 0.47 g, 0.60 g, 0.58 g; 0.51 g; and 0.69 g of methylcellulose. The results of methyl cellulose synthesis were tested with Degrees of Substitution, FT-IR spectroscopic analysis, and surface morphology using SEM. In the variation of methylene chloride, methylcellulose has the highest degree of replacement (14 g of 01,17). The formation of methyl cellulose is supported by FT-IR spectroscopy, namely with the appearance of vibration peaks in the wave number area of 3295.0 cm-1, which shows the -OH group, the C-H stretching group at wave number 2892.4 cm-1, the absorption peak that indicates the presence of C-O-C is found in wave numbers 1152.6 cm-1 and 1021.3 cm-1 where it is an asymmetrical and symmetrical stretching vibration. Morphological analysis using SEM showed that cellulose fibers' surface is smoother than methylcellulose. The average size of cellulose and methyl cellulose fibers is 4.791 μm and 3.828 μm, respectively. Morphological analysis using SEM showed that the surface fibers in cellulose were smoother than methylcellulose. The average size of cellulose and methyl cellulose fibers was 4.791 μm and 3.828 μm.

Synthesis of Cardanil Methyl Ether via Etherification Reaction Cardanol Isolated from Cashew Nut Shells (Anacardium occidentale L.) with Variations of Molar Methyl Iodide

The synthesis of the Cardanyl methyl ether is carried out through an etherization reaction between Cardanyl seed skin extract (CNSL) isolated from the methyl iodide. Cardanol is isolated with the addition of acetone, Ca(OH)2, NH4OH 25%, n-hexane: ethyl acetate (98:2), washing with NaOH 2.5%, HCl 5%, aquadest, and Na2SO4 anhydrate. The yield of the obtained cardanol is 74.39 g (74.39% of the initial weight of the CNSL) and has the following characteristics: acid count 1.2863 mgKOH/g, iodine count 215.6535 g I2/100 g, viscosity 38.7 cP, density 0.8266 g/mL, pH = 6.14. The FT-IR methyl ether Cardanyl spectrum shows an absorption band at 1162.9-1259.8 cm-1 shows a C-O stretching group at a wave number of 1043.6-1148.0 cm-1 showing the formation of an asymmetric and symmetrical C- O-C stretching band of the ether compound, the Spectra of the FT - IR methyl ether Cardanyl shows an absorptive band at 1162-1259-125,8 cm-1, showing a C-O stretching Group, at the wave number of 1043.6-1148.0 cm-1 indicating the formation, as a result, of an Asymmetric and Symmetric Stretching Group of the ethereal Compound. The Cardanyl methyl ether was synthesized by adding K2CO3, the solvent acetone and the iodide-methyl, with a reflux time of 8 hours. As for the parameters carried out in this study, the molar variation of the Cardanyl is the Methyl Iodide (1:1.5, 1:3, and 1:4.5) and yields 3.555 g; 12.084 g; 11.472 g of Cardanyl ether. Methyl ether Cardanyl was obtained in analysis with FT-IR and GC-MS spectroscopic photometers. The results of the analysis of Cardanyl methyl ethers with GC -MS were 63.28%, and the results of analysis of the Cardanyl ether with a variation of the molar ratio Cardanyl: Methyl iodide (1:1.5; 1:3; 1:4.5) with GC-MS obtaining 3.05%, 30.29%, and 26.58%. These results show the maximum percentage of methyl ethers Cardanyl at the reaction conditions of the variation molar ratios Cardanyl iodides (1:3), K2CO3 17.3 g, 50 mL of acetone, and 8 hours of reflux time.

One‐Pot/Simultaneous Synthesis of PHPMA‐G‐PLA Copolymers via Metal‐Free Rop/Raft Polymerization and their Self‐Assembly from Micelles to Thermoresponsive Vesicles

AbstractThe present article reports a simple and straightforward approach to access thermoresponsive graft copolymers based on lactide (LA) and a methacrylic monomer, 2‐hydroxypropyl methacrylate (HPMA), using a synthesized carboxy‐functionalized trithiocarbonate‐based chain transfer agent. One protocol involves a metal‐free simultaneous synthesis through a combination of reversible addition‐fragmentation chain transfer polymerization and organic acid‐catalyzed ring‐opening polymerization, which follows first‐order kinetics. The resulting copolymers with a controlled structure exhibit remarkably narrow molecular weight distributions (Ð < 1.10). Within this framework, the self‐assembly of PHPMA‐g‐PLA graft copolymers (GCs) into nanoparticles (NPs) is demonstrated at concentrations of 0.2 and 0.5 wt.%, respectively. The displacement method, based on the rapid injection of the organic solvent (acetone) into an aqueous medium under vigorous stirring, produces spherical NPs such as micelles, vesicles, or non‐spherical “lumpy rods”. The presence of a pseudo‐thermoresponsive segment (PHPMA) in GCs facilitates stimulus‐responsive self‐assembly behavior. Well‐defined spherical NPs—primarily vesicles of substantial size—develop upon heating above the glass transition temperature (Tg ≈35–36 °C) of the GCs in an acetone–water (80/20 wt.%) mixture. Last, specific interactions between the obtained PHPMA‐g‐PLA nano‐objects and blood proteins in human plasma are studied using isothermal calorimetry.

Glyburide in a series co-solvent solutions: Solubility and modeling, solvation and quantum chemistry research

The shake-flask technique was used to test the solubility of glyburide in mixtures of acetone + water and ethyl acetate + methanol/ethanol/isopropanol under 101.0 kPa. For a fixed temperature, the glyburide solubility positively increased with the mass fraction of acetone in the acetone + water mixture, and reached a maximum value of 8.805 × 10−6 at 298.15 K. The solubility magnitudes reach their peak when the mass fraction of ethyl acetate in solutions containing ethyl acetate plus methanol/ethanol/isopropanol is approximately 0.3, which correspond to 5.703 × 10−4, 5.235 × 10−4 and 4.307 × 10−4, respectively, at 298.15 K. Two models-the Jouyban-Acree and modified van't Hoff-Jouyban-Acree were employed to correlate the solutility and produced the biggest relative average deviation of 7.78 %. The local composition (solvents) around the drug molecule was investigated at 298.15 K using an inverse Kirkwood-Buff integrals. The positive preferred solvation parameters of glyburide were observed in the medium and rich compositions of methanol/n-propanol/isopropanol/acetonitrile/PG/NMP (taken from published works)/acetone, signifying that glyburide was preferentially solvated by these solvents; while they had negative magnitudes in ethyl acetate + methanol/ethanol/isopropanol systems throughout the whole ethyl acetate compositions. The solubility of glyburide in the ten solutions was properly described by an extended Hildebrand solubility parameter approach, with relative average errors of no more than 5.32 %. In addition, the electrostatic characteristics of the basicity/acidity of glyburide molecule were highlighted with the help of quantitative study of molecular surface. Because of their lowest (-158.0 kJˑmol−1 to −136.6 kJˑmol−1) and largest (156.6 kJˑmol−1 to 182.8 kJˑmol−1) global electrostatic potentials, the > C = O and > NH groups are the main targets of electrophilic and nucleophilic assault. Visual examination of the weak interactions between glyburide and the neat solvents (methanol, ethanol, isopropanol, acetone, ethyl acetate, and water) was done using the Hirshfeld partition analysis-based independent gradient model.

Amino acid and acetone fluorescence sensors based on a stable light-emitting Cd(II) metal-organic framework with derivatives of isonicotinic acid

As one of the most promising category of functional materials, luminescent metal–organic frameworks (LMOFs) have been widely investigated as fluorescence chemical sensors which can offer a reliable diagnostic tools in biomedical research. Herein, a luminescent Cd-MOF [Cd2(L)2(H2O)]n (Cd-MOF) (H2L = 3-(3-carboxylphenyl) isonicotinic acid), was synthesized by and characterized in detail. Single-crystal structure determination reveals that Cd-MOF crystalizes in the monoclinic crystal system with C2/c space group. Experimental results show that Cd-MOF is a highly selective and sensitive luminescent sensor for rapidly detecting acetone, l-Tryptophane (L-Trp) and l- Aspartic acid (L-Asp) in water. It can significantly test acetone in common solvents, selectively identify l-Trp-and l-Asp-in 12 amino acid aqueous solutions, and enhance the fluorescence signal of Tryptophan and quench l-Asp-with the detection limit of 17.6 μM and 68.8 μM respectively. However, upon the interaction with electron rich amino acid (L-Trp), the Cd-MOF shows the selective “Turn-On” behavior, which may also be supported by the DFT studies.

Optimised extraction of phospholipids and omega‐3 fatty acids from Patagonian squid waste with low‐toxicity solvents

SummaryExtracting conditions of lipid compounds (phospholipids, PLs; ω3 fatty acids, FAs) from Patagonian squid (Doriteuthis gahi) waste were optimised by employment of a Simplex‐Lattice design. For it, different concentrations of low‐toxicity solvents (ethanol, acetone and ethyl acetate; single and binary and ternary mixtures) were tested. As a result, the multiple regression anova proved that the quadratic model was significant (P < 0.05) for PL and eicosapentaenoic acid (EPA) contents and for total polyunsaturated/total saturated and total ω3/total ω6 FA ratios. Thus, the anova application of the fitting model led to the following optimised values for such parameters: 477.42 g kg−1 lipids, 21.48 g 100 g−1 total FAs, 3.48 and 13.03, respectively. The combination of process variable levels which maximised the desirability function (0.49 value) was ethanol/ethyl acetate (0.50:0.50, v/v) and led to values of 412.50 (g kg−1 lipids), 19.05 (g 100 g−1 total FAs), 2.59 and 12.86, respectively, for the above‐mentioned lipid parameters. Results were compared to those obtained by the conventional chloroform/methanol procedure. By including an advanced mathematical design, a novel eco‐friendly strategy based on the employment of low‐toxicity solvents is proposed for the extraction from a marine waste substrate of highly valuable lipid compounds with healthy and nutritional properties.

Phytochemical analysis and antimicrobial activity of Tamarindus indica extracts against Fusarium oxysporum and Xanthomonas campestris

Abstract. Gitari FM, Githae EW, Kuria EK. 2023. Phytochemical analysis and antimicrobial activity of Tamarindus indica extracts against Fusarium oxysporum and Xanthomonas campestris. Intl J Trop Drylands 7: 73-82. Plant-pathogenic bacteria and fungi are a major threat to biodiversity and food security worldwide. The pathogens are difficult to control using cultural methods and have sometimes acquired resistance to conventional pesticides. This has necessitated the search for more efficient active compounds against them. One promising source of such compounds is tropical-medicinal plants such as Tamarindus indica L. This study first determined the phytochemical composition of T. indica extracts from different parts (leaves, bark, roots, and pods). Then it evaluated in-vitro the antimicrobial activity against plant pathogenic bacteria (Xanthomonas campestris) and fungi (Fusarium oxysporum). Crude extracts were obtained using different solvents (dichloromethane, methanol, and acetone). The analysis revealed the presence of nine pharmaco-active phytochemicals; methanol extracts had the highest concentrations of these phytochemicals. All extracts demonstrated inhibitory effects against F. oxysporum. However, the extracts did not show any antimicrobial effect against X. campestris. There was a significant difference (p<0.05) in the percentage of inhibition of F. oxysporum growth by different extracts. Generally, high growth inhibition was observed in media containing different plant extracts at 250 and 500 ppm concentrations. For acetone extracts, the highest inhibition (71.042%) was induced by root extract at a 250 ppm concentration, whereas for dichloromethane extracts, the highest inhibition (68.811%) was induced by 500 ppm of leaf extract. Methanol extracts from stem recorded the highest inhibition of 86.953% at concentrations of 125 ppm. This was followed by root extracts (75.169% inhibition) at 500 ppm. The T. indica, therefore, has great potential as a source of bio-pesticide for use in integrated pest management of F. oxysporum.

Precipitation Using Organic Solvents for Purifying Lipase from Preussia africana

Aims: The present study aimed to purify a new lipase from the endophytic fungus Preussia africana (P. africana).
 Study Design: Lipases were produced through fermentation and precipitation using different organic solvents and characterized at optimal temperature and pH conditions.
 Place and Duration of Study: Assays were carried out at the Laboratory of Bioprocess at the Federal University of Alfenas between January and August, 2023.
 Methodology: Enzymes were produced via submerged fermentation. After fermentation, the broth was filtered and lyophilized so that enzymes were concentrated. Organic solvents (methanol, ethanol, isopropanol and acetone) were used at 10 and 25°C for lipase precipitation. A second precipitation step was investigated in a supernatant: solvent ration ranging from 1:3 to 1:2 (v/v) and temperatures between 10°C and 25°C. Optimal temperature and pH conditions for the hydrolytic activity of precipitated lipase were also found.
 Results: Acetone and isopropanol were more efficient in precipitating lipase while maintaining its catalytic activity, as specific activities of 211.34 ± 0.05 and 179.50 ± 0.08 U/mg were achieved, respectively. For the second precipitation step, acetone in a supernatant: solvent ratio of 1:2 (v/v) at 10°C achieved optimal performance, as purification factor of 1.89 ± 0.01 and recovered activity of 93.45% were found. Maximum hydrolytic activity of 72.80 ± 1.29 U/mL was observed using olive oil as substrate at pH between 7 and 8 and 37°C.
 Conclusion: The use of acetone at 10°C in two precipitation steps proved to be a more robust strategy for P. africana lipase precipitation in the purification process.