System Ethyl Acetate Research Articles

Screening of Process Parameters for Aspirin Loaded PLGA Microsphere

Background amp Aim Aspirin a non-steroidal anti-inflammatory drug has the potential to stimulate various dental stem cells and promotes regeneration of dental tissues. Polylactic glycolic acid PLGA a biocompatible and biodegradable polymer has the potential to stimulate multiple processes such as proliferation osteogenic differentiation initiation of mechanical support and formation of three-dimensional niches for the growth of new tissue. Hence this study aimed to identify the most effective formulation and process variables for developing aspirin polylactic glycolic acid microspheres using the Placket-Burman method.Method In the screening study Placket-Burman screening was systematically employed to estimate all of the parameter effects and interactions. The microspheres were formulated using the double-emulsion solvent extraction method by varying various variables and performing statistical analysis. Eight independent variables were considered for screening with encapsulation efficiency as the dependent variable. These variables included the volume of the internal phase of primary emulsion solvent system ethyl acetate ethanol homogenization time stirring speed emulsification time flow rate poly vinyl alcohol concentration and PLGA concentration.Results Encapsulation efficiency varied between 50.11 and 88.98. The concentration of PLGA and Poly vinyl alcohol and the volume of the internal phase were found to have a significant influence on encapsulation efficiency in the synthesis of Aspirin PLGA microsphere.Conclusion Among the eight independent variables assessed for screening the concentrations of PLGA and polyvinyl alcohol and the volume of the internal phase were found to significantly impact the encapsulation efficiency in the formulation of aspirin PLGA microspheres.

Optimization of Color Fractionation of Monascus Pigment

Monascus fungi are unique among the various microorganisms that produce edible pigments, which consist of red, orange and yellow. These pigments are typically present in a mixture. Hence, pigment separation is needed. This study aims to optimize solvent systems that can effectively fractionate the pigments. The optimization was carried out using column chromatography and the data was analyzed using Central Composite Design (CCD). The interaction of the solvent systems ethyl acetate : formic acid : acetic acid : water was optimized. The optimal solvent system obtained was 98 : 14 : 12 : 28 (vol/vol.) for ethyl acetate : formic acid : acetic acid : water, respectively. The red and yellow pigment obtained were 2.42 mg and 0.93 mg, respectively. Based on the finding, 72.2% of the Monascus pigments was red while remaining was yellow.

Musk ketone solubility in binary systems ethyl acetate with methanol, ethanol, and isopropanol: preferential solvation according to the inverse Kirkwood–Buff integrals method

ABSTRACT Three co-solvent mixtures {methanol (1) + ethyl acetate (2), ethanol (1) + ethyl acetate (2), and isopropanol (1) + ethyl acetate} were used to calculate the preferred solvation parameters () of musk ketone (MK) (2). In all co-solvent mixes, values vary non-linearly with the percentage of co-solvent (1). According to the study, values are negative in mixes rich in alcohol but positive in those high in ethyl acetate. The mixtures {methanol (1) + ethyl acetate (2)} and {ethanol (1) + ethyl acetate (2)} show the most favoured solvation of MK by ethyl acetate at 298.15 K and 293.15 K, respectively. When {isopropanol (1) + ethyl acetate (2)} is combined; it is maximum at 298.15 K. Since the values are positive, MK preferentially solvates with ethyl acetate. The most significant values for x 1 = 0.18–0.40 are obtained towards the non-polar regions of MK for the three co-solvent mixes.

Novel antimicrobial activities of self-nanoemulsifying drug delivery system (SNEDDS) ethyl acetate fraction from Garcinia mangostana L. peels against Staphylococcus epidermidis: Design, optimization, and in vitro studies

Novel antimicrobial activities of self-nanoemulsifying drug delivery system (SNEDDS) ethyl acetate fraction from Garcinia mangostana L. peels against Staphylococcus epidermidis: Design, optimization, and in vitro studies

In-Vitro Anti-inflammatory Activity of Methanolic Extract of Convolvulus pluricaulis Choisy

Aim: In-Vitro Anti-inflammatory Activity of Methanolic Extract of Convolvulus pluricaulis Choisy.
 Material & Methods- The whole plant parts of Convolvulus pluricaulis Choisy were purchased from the local market. Whole plant materials were dried under shade and subjected to coarse powder for extraction process. Accurately weighed quantity of whole plant material was extracted using 95 % methanol by soxhlet apparatus for 72 h. Qualitative chemical tests of methanolic extracts were subjected to various chemical tests to detect various phytoconstituents. Solvent systems ethyl acetate: methanol: water (77:13:10) were found to be most satisfactory solvent system. After development of plates, they were air-dried and number of spots, color and Rf values were recorded. The % heamolysis was calculated by assuming the heamolysis produced by the control group as 100 %.
 Results: The preliminary phytochemical analysis revealed that different active constituent present in different extracts such as carbohydrates, proteins, amino acids, fat, oils, steroids, terpenoids, glycosides, alkaloids, tannins and other phenolics compounds. At a concentration of 500 µg/ml, the extract produced 71.59% protection of RBC haemolysis as compared with 72.73% produced by prednisolone. The methanolic extract of selected plant showed 39.70% inhibition. The Diclofenac sodium showed 55.88 % inhibition against denaturation of protein.
 Conclusion: In conclusion, it can be stated that the methanolic extract has beneficial effects in long lasting in membrane stabilizing method, inhibition of protein denaturation method and proteinase model.
 Keywords: In-Vitro, Anti-inflammatory Activity, Methanolic Extract, Convolvulus pluricaulis Choisy, Protein Denaturation Method

Quantitative Determination of Aloin in Aloe vera and Its Antioxidant Activity

Aloe vera is a popular medicinal plant used widely by the cosmetic, pharmaceutical and food industries. The Aloe vera gel, which is used mostly for its positive effects on human health,contains over 75 different bioactive compounds, including aloin. A sensitive and reliable densitometric High Performance Thin Layer Chromatography method has been developed for the quantification of aloin, an anthraquinone present in Aloe vera leaves. Chromatographic analysis was performed using methanol extract of leaves of Aloe vera using solvent system ethyl acetate: Methanol: water (100:13.5:10). Detection and quantification of aloin was done by densitometric scanning at 350nm. The results of linearity range and correlation coefficient show that there was a good correlation between peak area and corresponding concentration of aloin. The method developed here in can be implemented in the analysis and routine quality control of herbal materials. Antioxidant activity of Aloe vera was also done by using DPPH method and found that Aloe vera is also a natural antioxidant.

Water‐insoluble cosolvent in aqueous two‐phase system improved the extraction of paeonol from cortex moutan

AbstractBackgroundAqueous two‐phase extraction has advantages of green extraction, high yield, good product purity and low cost. However, conventional aqueous two‐phase systems (ATPSs) are limited in extraction/separation due to high polarity. Some researchers tuned the hydrophobicity of ATPSs by addition of hydrophobic ionic liquids or polymers. We aimed to tailor the hydrophobicity of a solvent–salt–water ATPS using cosolvent for extraction of paeonol from cortex moutan.ResultsTie‐line length and compositions in the ATPS were employed for qualitative evaluation of polarity and polarity difference between the two phases. Conditions such as pH, salt type and concentration, total solvent volume fraction and cosolvent fraction were optimized. Ethyl acetate (EA) as cosolvent in ethanol–NaH2PO4–H2O (EtPO) system did not alter the first‐order kinetic extraction model, but it improved the kinetic constant and boosted the partition coefficient from 36.7 to 58.8. For both EtPO and EtPO–EA systems, both the extraction yields and partition coefficients increased when temperature increased from 11 to 37 °C. The optimized EtPO–EA system demonstrated higher extraction yield than EtPO and 70% (v/v) ethanol systems by 25.4 and 19.5%, respectively.ConclusionsThe hydrophobicity of an ATPS was successfully tuned with cosolvent for paeonol extraction. The cosolvent–salt–water two‐phase systems are promising in extraction of weakly polar components from herbs. © 2019 Society of Chemical Industry

Isobaric Vapor Liquid Equilibria for Binary Mixtures of Isoamyl Acetate + Ethyl Acetate at 50 and 100 kPa

In this work new phase equilibria data for the system ethyl acetate + isoamyl acetate at pressures of 50 and 100 kPa are reported. The measures were carried out in the equilibrium apparatus FISCHER LABODEST VLE 602D, which is essentially a dynamic equilibrium cell equipped with a Cottrell recirculation pump. The quality of the experimental information was examined with the Wisniak point criteria because binary mixtures under study offer small deviations from the ideality. The nonrandom two-liquid and universal quasichemical activity models with symmetrical parameters were used to correlate experimental data, and both activity models show good correlation with experiments and can be used in distillation process calculations.

Optimal Design and Effective Control of Triple-Column Extractive Distillation for Separating Ethyl Acetate/Ethanol/Water with Multiazeotrope

The separation of the ternary nonideal system ethyl acetate (EtAC)/ethanol (EtOH)/water with multiazeotropes is very important since they are always generated in the production process of n-butanol...

Liquid-liquid extraction pretreatment samples method used for pharmacokinetic study of rhubarb in rats after oral administrated

Abstract Objective Pretreatment of biological samples is the most critical step in pharmacokinetic studies, especially pre-treatment of plasma samples. The pretreatment of biological samples in pharmacokinetic study of Traditional Chinese Medicines (TCM) is difficult due to the complexity of the ingredients. An organic solvent system ethyl acetate: acetone (10: 1) solution used for liquid-liquid extraction has been developed in this study and compared with the commonly used protein precipitation method. Methods Rats, Beagle dogs and humans plasma samples were adopted in this study in order to demonstrate the universality of the pretreatment method. Feasibility of this pretreatment method was also verified through its application to the pharmacokinetics of rhubarb in rats. Results According to the results of extraction recovery matrix effect, it was indicated that the liquid-liquid extraction methods with new organic solvent might be suitable for variety of structures of compounds and various types of plasma samples. The pharmacokinetic study result showed that the developed pretreatment method could successfully be used for simultaneous determination of three active compounds modin, emodin-8-O-β-D-glucopyranoside (EDG) and rhein in rat plasma with high sensitivity, accuracy, and recovery by liquid chromatography tandem mass spectrometry (LC-MS/MS). Conclusion: The pretreatment method of liquid-liquid extraction methods with new organic solvent could be successfully applied for multi-component pharmacokinetics of TCM.

Acute And Subchronic Toxicity Studies Of SNEDDS (Self Nanoemulsifying Drug Delivery Systems) From Ethyl Acetate Extract Of Bay Leaf (Eugenia polyantha W.) with Virgin Coconut Oil As Oil Phase

Bay leaf (Eugenia polyantha) is widely used as an alternative therapy for diabetic and hypercholesterol. However, the administration of the extract has a low oral bioavailability, therefore it is prepared by Self Nanoemulsifying Drug Delivery Systems (SNEDDS) ethyl acetate extract of bay leaf. Therefore, acute and subchronic toxicity test is required. The toxicity test performed was an experimental study, including acute and subchronic toxicity tests. Animal experiments were used using Wistar strain rats. Acute toxicity test using 5 groups (n=5) consisted of 1 control group and 4 groups of SNEDDS dose with 48 mg/kgBW 240 mg/kg, 1200 mg/kg, and 6000 mg/kg, while for subchronic toxicity test with 1 group control and 3 groups of doses of SNEDDS with dose group variation 91.75 mg/kgBW, 183.5 mg/kg, and 367 mg/kg. Duration of observation at acute toxicity test for 14 days while for subcronic toxicity test for 28 days with continuous SNEDDS dosage. The results of the acute toxicity test showed toxic symptoms and obtained median lethal dose (LD50) values from SNEDDS from ethyl acetate extract of bay leaf 1409.30 mg/kgBW belonging to slightly toxic category. Subchronic toxicity studies show that the test drug has minor damage in liver and kidneys and moderate damage in pancreas.

Determination and Thermodynamic Analysis of the Solubility of Limonin in Eight Organic Solvents and Ethyl Acetate + 2-Propanol Binary Solvents from 283.2 to 323.2 K

In the present study, the solubility of limonin in eight organic solvents and a binary solvent system (ethyl acetate + 2-propanol) was determined by the high-performance liquid chromatography analysis method within the temperature range from 283.2 to 323.2 K. The results showed that the solubility of limonin increased with temperature in the eight pure solvents and the binary solvent mixtures. In the binary solvent system ethyl acetate + 2-propanol, the solubility decreased with the initial mole fraction of ethyl acetate. The experimental solubility of limonin was well correlated with temperature by the simplified thermodynamic equation, modified Apelblat equation, λh equation, and NRTL equation. Furthermore, the solubility of limonin in the binary solvent mixtures was correlated with both temperature and initial solvent composition of the binary solvent mixtures by the Jouyban–Acree model, van’t Hoff–Jouyban–Acree model, modified Apelblat–Jouyban–Acree model, Ma model, Sun model, and NRTL model. Finally,...

Chromatographic Fingerprinting of Sarasvata Churna-an Ayurvedic Polyherbal Formulation for Epilepsy

Sarasvata churna is an Ayurvedic formulation prescribed for Epilepsy and other brain related disorders. The objective of this study is to explore bioactive principles present in Sarasvata churna using GCMS and HPTLC techniques and establishing their correlation in Epilepsy treatment. The volatile oil obtained by hydro-distillation was used for the GCMS analysis and methanolic extracts were used for HPTLC studies. HPTLC fingerprints for the formulation and method for simultaneous qualitative analysis of biomarkers in the formulation was developed using HPTLC. The GCMS report shows the presence of α-Pinene, Propanal, 2-Caren-10-al, 3-Caren-10-al, Caryophyllene, Epiglobulol, Asarones, α-selinene, α-sesquiphellandrene, o-cymene, copaene etc. HPTLC fingerprints for methanolic extracts of Sarasvata churna was established with good separation and resolution in solvent system Toluene:Ethylacetate:Methanol (7.5:2.5:0.5v/v/v). The HPTLC method for simultaneous analysis of marker compounds in the formulation was developed in solvent system Ethylacetate:Glycial acetic acid:Toluene:Water (4:1:1:0.5v/v/v/v) with Rf 0.77 for Piperine, 0.07 for Bacosides and Rf 0.57 for Withnolides in the reference compounds and methanolic extracts of Sarasvata churna. Chromatographic patterns of reference compounds were easily detectable in the tracks of Sarasvata churna methanolic extracts. The chromatographic standards obtained from this study will help in chemical standardization of Sarasvata churna and enhance the use Sarasvata churna for management of Epilepsy.

ИЗУЧЕНИЕ ФЕНОЛЬНЫХ СОЕДИНЕНИЙ НАДЗЕМНОЙ ЧАСТИ ХАТЬМЫ ТЮРИНГЕНСКОЙ, ПРОИЗРАСТАЮЩЕЙ НА ТЕРРИТОРИИ АЛТАЙСКОГО КРАЯ

Lavatera thuringiaca L. family Malvaceae (Malvaceae) contains a rich complex of biologically active compounds and is widely used in folk medicine as an anti-inflammatory, enveloping, expectorant agent. The goal of this research is to study of phenolic compounds in aboveground part of Lavatera thuringiaca, growing in the Altai Region. To achieve the goal needs to solve the following problem: conducting qualitative reactions to flavonoids, separation and identification of phenolic compounds by TLC and HPLC. The results of qualitative reactions allowed to sugges the presence in the raw material of flavonoids groups flavonol, flavone, flavanone. Using the method of thin layer chromatography in the system ethyl acetate - acetic acid - water (70:10:20) detected flavonoids flavone and flavonol groups. Then prepared ethanolic extraction and separation was divided into fractions: ether, ethylacetate and butanolic. By HPLC in the ester fraction were identified caffeic acid, coumaric derivatives and ferulic acid, flavonoids of flavone, trimethoxyflavone, isoflavone groups, chalcone derivative; in ethyl acetate fraction - caffeic acid, gallic derivatives and ferulic acids, flavonoids of flavone, trimethoxyflavone groups; in butanol fraction - flavonoid of group flavone, apigenin and catechol derivatives. The research aimed at studying the possibility of applying the aboveground part of the Lavatera thuringiaca in medicine. It is planned to develop standard documentation on medicinal plant raw material.

Alpha-amylase Inhibition and Brine Shrimp Lethality Activities of Nine Medicinal Plant Extracts from South-West Nigerian Ethnomedicine

ABSTRACTAcanthospermum hispidum, Alchornea laxiflora, Calyptrochilum christyanum, Heliotropicum indicum, Holarrhena floribunda, Ipomoea asarifolia, Nauclea diderrichii, Piper guineense, and Tetracera scandens were extracted into methanol and screened for the availability of alpha-amylase inhibitors. Plant extracts’ toxicity was determined by brine shrimp lethality assay (BSLA). The most active plant, Nauclea diderichii, was fractionated into four solvent systems (n-hexane fractions, ethyl acetate, dichloromethane, and n-butanol) and tested. All the extracts showed varying degrees of alpha-amylase inhibitory activity. N. diderrichii with IC50 = 248.30 ± 0.27 µg.mL–1 had the highest inhibitory activity, while its butanol fraction with IC50 = 137.8 µg.mL–1 had activity comparable to the standard α-amylase inhibitor acarbose (IC50 = 177.50 ± 0.42 µg.mL–1). LC50 values for BSLA ranged from 11.35 to 1,127.50 µg.mL–1, with T. scandens being the most toxic with 11.35 µg.mL–1 and N. diderrichii the least toxic with 1,127.50 µg.mL–1.

The isobaric vapor liquid equilibria of ethyl acetate + acetonitrile + bis(trifluoromethylsulfonyl)imide-based ionic liquids at 101.3 kPa

We investigated the isobaric vapor liquid equilibria (VLE) of the binary system ethyl acetate + acetonitrile, the ternary system ethyl acetate + acetonitrile + 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide([EMIM][NTf2]), as well as ethyl acetate + acetonitrile + 1-hexyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide([HMIM][NTf2]) at 101.3 kPa in a modified Othmer still. The experimental data were correlated with the e-NRTL activity coefficient model, and the parameters were obtained with a good consistency. The results indicated that ionic liquids([EMIM][NTf2] and [HMIM][NTf2]) produced a consistent salting-out effect of ethyl acetate, resulting in the incremental relative volatility of ethyl acetate to acetonitrile and even eliminated the azeotropic phenomenon when the mole fraction of ILs was up to 0.05.

Ultrasonic Speed and Related Thermo-acoustical Parameters of Solutions of 1,1′-Bis(3-methyl-4-ethoxyacetylphenoxy)cyclohexane at Four Different Temperatures

The density (ρ), viscosity (η) and ultrasonic speed (U) of the pure solvents: 1,4-dioxane (DO), ethyl acetate (EA), tetrahydrofuran (THF) and solutions of the biologically active 1,1′-bis(3-methyl-4-ethoxyacetylphenoxy)cyclohexane were investigated at four temperatures: 298, 303, 308 and 313 K over a wide range of concentrations (0.1–0.01 mol·dm−3) to understand molecular interactions in these solutions. Various acoustical and thermodynamic parameters such as specific acoustical impedance (Z), isentropic (adiabatic) compressibility (κS), Rao’s molar sound function (Rm), van der Waals constant (b), internal pressure (π), free volume (Vf), intermolecular free path length (Lf), classical absorption coefficient {(α/f2)Cl}, viscous relaxation time (τ), Gibbs energy of activation (ΔG*), enthalpy of activation (ΔH*) and entropy of activation (ΔS*) were determined using the ρ, η and U data. A good to excellent correlation between a given parameter and concentration (C) is observed at all temperatures (T) and solvent systems studied. A linear increase or decrease of acoustical and thermodynamic parameters with concentration and temperature indicate the presence of strong molecular interactions in the solutions. ΔG* decreases linearly with increasing concentration and temperature in the DO system, while it decreases with C and increases with temperature in the EA and THF systems. The enthalpy of activation (ΔH*) was found to be practically independent of concentration but ΔH* and ΔS* were found to be slightly concentration dependent. In the DO system they are positive, while in the EA and THF systems they are negative.

Rapid separation of three proanthocyanidin dimers from Iris lactea Pall. var. Chinensis (Fisch.) Koidz by high‐speed counter‐current chromatography with continuous sample load and double‐pump balancing mode

The dried seeds of Iris lactea have been used in traditional Chinese medicine. Previous studies have been focused on irisquinones while other chemical components are rarely reported. To establish an efficient high-speed counter-current chromatography (HSCCC) separation method with continuous sample load (CSL) and double-pump balancing (DPB) mode to isolate proanthocyanidins from I. lactea. Firstly, an ethyl acetate extract of I. lactea was pre-fractionated by silica column chromatography for the enrichment of proanthocyanidins. Secondly, the enriched proanthocyanidins sample (EPS) was further fractionated by HSCCC with a two-phase solvent system ethyl acetate:n-butanol:water (9:1:10, v/v/v) using DPB mode. The flow rate of the two phases was 2.2 mL/min, the revolution speed was 900 rpm, the separation temperature was 30 °C and the detection wavelength was 280 nm. Finally, the structures of the three isolated proanthocyanidins were elucidated by spectroscopic methods and compared with published data. Under the optimized conditions, 600 mg of the EPS with six continuous injections (100 mg/time) was fractionated, yielding 57 mg of prodelphinidin B3, 198 mg of procyanidin B3, and 162 mg of procyanidin B1, at purities of 97.2%, 98.1% and 97.3%, respectively. The HSCCC separation method with CSL and DPB proved to be rapid, convenient and economical, constituting an efficient strategy for the isolation of proanthocyanidins.

Thermo-Acoustical Study of Biologically Active 1,1’-Bis(3-Methyl-4-Carboxyethylphenoxy) Cyclohexane at Four Different Temperatures

Density (ρ), viscosity (η), ultrasonic speed (U), and thermo-acoustical parameters such as specific acoustical impedance (Z), adiabatic compressibility (κa), internal pressure (π), free volume (Vf), inter molecular free path length (Lf), Van der Waals constant (b), viscous relaxation time (τ), classical absorption coefficient (α/f2)cl, Rao’s molar sound function (Rm), solvation number (Sn), Gibbs free energy of activation (ΔG*), enthalpy of activation (ΔH*) and entropy of activation (ΔS*) of biologically active 1,1’-bis (3-methyl-4-carboxyethylphenoxy) cyclohexane (BMCPC) in 1,4-dioxane (DO), ethyl acetate (EA), tetrahydrofuran (THF) have been studied at four different temperatures: 298, 303, 308 and 313 K to understand the molecular interactions in the solutions. A good to excellent correlation between a given parameter and concentration is observed at all temperatures and solvent systems studied. Linear increase or decrease [except (α/f2)cl ] of acoustical parameters with concentration and temperature indicated the existence of strong molecular interactions. ΔG* decreased linearly with increasing concentration and temperature in DO and EA systems and increased with temperature in THF system. ΔH* and ΔS* are found practically concentration independent in case of DO and EA system but both are found concentration dependent in THF system.

Thermo-Acoustical Study of Biologically Active 1,1’-Bis(3-Methyl-4-Carboxyethylphenoxy) Cyclohexane at Four Different Temperatures

Density (ρ), viscosity (η), ultrasonic speed (U), and thermo-acoustical parameters such as specific acoustical impedance (Z), adiabatic compressibility (κa), internal pressure (π), free volume (Vf), inter molecular free path length (Lf), Van der Waals constant (b), viscous relaxation time (τ), classical absorption coefficient (α/f2)cl, Rao’s molar sound function (Rm), solvation number (Sn), Gibbs free energy of activation (ΔG*), enthalpy of activation (ΔH*) and entropy of activation (ΔS*) of biologically active 1,1’-bis (3-methyl-4-carboxyethylphenoxy) cyclohexane (BMCPC) in 1,4-dioxane (DO), ethyl acetate (EA), tetrahydrofuran (THF) have been studied at four different temperatures: 298, 303, 308 and 313 K to understand the molecular interactions in the solutions. A good to excellent correlation between a given parameter and concentration is observed at all temperatures and solvent systems studied. Linear increase or decrease [except (α/f2)cl ] of acoustical parameters with concentration and temperature indicated the existence of strong molecular interactions. ΔG* decreased linearly with increasing concentration and temperature in DO and EA systems and increased with temperature in THF system. ΔH* and ΔS* are found practically concentration independent in case of DO and EA system but both are found concentration dependent in THF system.