Hexyl Acetate Research Articles

VOLATILE COMPOUNDS IN GOLDEN DELICIOUS APPLE FRUIT (Malus domestica) DURING COLD STORAGE

Biosynthesis of volatile compounds (VC), as well as activity of related enzymes (lipoxygenase LOX, alcohol acyltransferase AAT, and alcohol dehydrogenase ADH), and fatty acids (palmitic, stearic, oleic, linoleic and linolenic acids) were assessed in Golden Delicious fruit apples (Malus domestica Borkh.) during 1 ºC storage at different atmosphere conditions. Three atmosphere conditions were used: 21 % O2 and > 1 % CO2 (Regular Atmosphere, RA), 3 % CO2 and 2 % O2 (Controlled Atmosphere, CA), and CA, with 7 d under RA conditions (CA + RA), to evaluate the effect of shorts periods under air storage. CA conditions inhibited the production of butyl acetate and hexyl acetate esters, and increased hexanol concentration. Production of the branched ester 2-methyl butyl acetate did not decrease under CA conditions. As a result of 7 d under RA, butyl acetate and hexyl acetate in CA + RA increased, mainly after one month of storage. Storage under CA conditions inhibited LOX and AAT activity at some stages whereas ADH activity increased during CA storage. LOX activity showed high correlation with production of aldehydes (r2 = 0.85) and cis-2-hexenal (r2 = 0.94), during storage of apples under CA conditions. Good correlation was found between AAT activity and total esters and butyl acetate content under CA storage of apples (r2 = 0.92 and r2 = 0.93, respectively). While most fatty acids increased in concentration during RA and CA storage, linolenic acid content decreased. No correlation between volatile compounds content and fatty acid production was found.

Genetically engineered Oenococcus oeni strains to highlight the impact of estA2 and estA7 esterase genes on wine ester profile

Besides deacidifying wine, Oenococcus oeni bring significant changes in the chemical composition of wine by releasing esters by the action of their own esterases. The impact of O. oeni esterases remains relatively unexplored. Four esterase genes were identified from O. oeni genome (estA2, estA7, estC, and estB). The dual objective of this study was, first to use a genetic tool enabling the expression of esterase genes in enological conditions and, second, to investigate the impact of O. oeni esterase gene expression during winemaking on wine aromatic profile. Both estA2 and estA7 genes were successfully cloned and expressed in O. oeni and recombinant strains were inoculated in Aligoté wine to initiate malolactic fermentation (MLF). Ester profile of experimental wine was established by SPME-GC-MS. EstA2 caused significant decreases in the concentrations of isoamyl acetate, ethyl hexanoate, isobutyl acetate, and hexyl acetate, by 42.7%, 23.4%, 51.5%, and 28.9%, respectively. EstA2 has preferential hydrolytic activity toward acetate esters from higher alcohols. EstA7 has synthetic activity toward hexyl acetate with a significant 22.7% increase. This study reports the first efficient expression system enabling the production of a functional protein in O. oeni in enological conditions.

Determination of Fatty Acid Composition, Volatile Components, Physico-Chemical and Bioactive Properties of Grape (Vitis vinifera) Seed and Seed Oil

The aim of this research was to examine some physico-chemical and antioxidant properties, fatty acid composition, volatile components and effect on oxidative stability of corn oil in terms of induction period of five different grape seeds. The obtained results revealed that extraction solvent and grape variety had significant effect on bioactive properties. When the grape seed acetone: water (90:10) extracts (2,000 ppm) was added to corn oil, the induction periods at 120C was measured, and the obtained results showed that the added grape seed extracts provided better oxidative stability to corn oil. Various classes of volatile compounds have been detected in seeds such as esters, hydrocarbons, alcohols, aldehyde and acid among which most abundant were isoamyl and hexyl acetate. It could be concluded that grape seeds may be used for the preservation of food products and health supplements. Practical Applications Proximate analysis showed that grape seeds contained high amounts of oil and crude protein. Extraction solvent and grape variety had a significant effect on bioactive properties. Twenty-seven volatile compounds were detected in grape seeds from various classes such as ester, hydrocarbon, alcohol, aldehyde and acid. According to the rancimat test results, grape seed extracts provided better oxidative stability to corn oil.

Modification of interactions between selected volatile flavour compounds and salt-extracted pea protein isolates using chemical and enzymatic approaches

Effects of chemical (acetylation and succinylation) and enzymatic (Alcalase) modifications on the binding properties of salt-extracted pea protein isolates (PPIs) to 2-octanone, octanal, hexyl acetate and dibutyl disulfide were monitored using GC/MS and related to changes in protein structure, based on differential scanning calorimetry and native-PAGE analyses. Addition of acetic and succinic anhydrides from zero to one gram per gram of protein gradually released the bound octanal and hexyl acetate mainly due to the loss of reactive NH2 and OH groups and dissociation of protein inherent structure. Initial addition of these dicarboxylic acid anhydrides (<0.1 g) resulted in partial denaturation of PPIs and increased binding for 2-octanone and dibutyl disulfide; however, further addition of anhydrides reduced retention of these flavour compounds probably due to extensive protein denaturation and masking of free SH groups on the protein. The binding of dibutyl disulfide was found to be positively correlated with the number of free sulfhydryl groups on acylated PPIs inferring potential sulfhydryl-disulfide interchange reactions. Enzymatic hydrolysis of PPIs by Alcalase released bound ketone and ester flavours; however, the retention levels for aldehyde and disulfide flavours were enhanced. A strong relationship was found between protein-flavour binding affinities, the type of flavour and the structure of the protein as affected by different protein modification methods.

Probing the molecular forces involved in binding of selected volatile flavour compounds to salt-extracted pea proteins

Molecular interactions between heterologous classes of flavour compounds with salt-extracted pea protein isolates (PPIs) were determined using various bond disrupting agents followed by GC/MS analysis. Flavour bound by proteins decreased in the order: dibutyl disulfide>octanal>hexyl acetate>2-octanone=benzaldehyde. Benzaldehyde, 2-octanone and hexyl acetate interacted non-covalently with PPIs, whereas octanal bound PPIs via covalent and non-covalent forces. Dibutyl disulfide reacted with PPIs covalently, as its retention was not diminished by urea and guanidine hydrochloride. Using propylene glycol, H-bonding and ionic interactions were implicated for hexyl acetate, benzaldehyde, and 2-octanone. A protein-destabilising salt (Cl3CCOONa) reduced bindings for 2-octanone, hexyl acetate, and benzaldehyde; however, retention for octanal and dibutyl disulfide increased. Conversely, a protein-stabilising salt (Na2SO4) enhanced retention for benzaldehyde, 2-octanone, hexyl acetate and octanal. Formation of a volatile flavour by-product, 1-butanethiol, from dibutyl disulfide when PPIs were treated with dithiothreitol indicated occurrence of sulfhydryl–disulfide interchange reactions.

Liquid–liquid equilibria study of the (water + phosphoric acid + hexyl or cyclohexyl acetate) systems at T = (298.15, 308.15, and 318.15) K: Measurement and thermodynamic modelling

Liquid–liquid equilibrium (LLE) data for the (water+phosphoric acid+n-hexyl acetate or cyclohexyl acetate) ternary systems were determined at T=(298.15, 308.15 and 318.15)K and p=101.3kPa. The cloud point method was used to obtain the solubility and the Karl-Fischer, acidimetric titration, and refractive index methods were used to determine the tie-line values. Both the ternary systems exhibit type-1 behavior of LLE. The experimental values were regressed and acceptably correlated using the UNIQUAC and NRTL models. The reliability of the experimental tie lines was confirmed using the Othmer–Tobias plot. Experimental distribution coefficients and separation factors were fitted using the Kamlet–Taft LSER model. The influence of temperature on the biphasic area and separation factor was found to be minor. As a result, both the esters are suitable separating agents for aqueous phosphoric acid mixtures.

Improvement of Malvar Wine Quality by Use of Locally-Selected Saccharomyces cerevisiae Strains

Malvar grape juice offers relatively little in the way of a sensory experience. Our interest lies in the use of locally-selected yeast strains in experimental fermentations to improve the sensory characteristics of Malvar wines. Two locally-selected strains of Saccharomyces cerevisiae were used as starter cultures in vinifications and compared with spontaneous fermentations of the same cultivar musts. Wine quality was investigated by their principal oenological parameters, analysis of the volatile aroma components, and corroborated by an experienced taster panel. The most salient chemical attributes were its high concentrations of isoamyl acetate and hexyl acetate and the high acidity, which have been detected to be key constituents in setting the fruity and fresh character of Malvar wines. Winemakers of winegrowing areas where this grape variety is cultivated will have improved options to elaborate new white wines styles, using selected yeast strains that enhance its aromatic properties.

Comparative analysis of aroma compounds in ‘Bartlett’ pear in relation to harvest date, storage conditions, and shelf-life

In this study ‘Bartlett’ pear fruit from two harvest dates were stored under normal atmosphere and ultra-low oxygen (ULO: 0.8kPa O2, <0.5kPa CO2) at +1°C and −1°C. Storage under ULO at −1°C greatly delayed ripening, as demonstrated by maintained firmness and suppressed synthesis of aroma volatiles after storage. ULO storage also suppressed synthesis of esters, including two character-impacting compounds: methyl and ethyl (2E,4Z)-deca-2,4-dienoate. Synthesis of hexyl acetate was suppressed under ULO storage regardless of temperature, while ethyl acetate synthesis was suppressed only by ULO at −1°C. The levels of most aroma volatiles were recovered after the following 10 d of shelf-life, although with significantly lower recovery for methyl and ethyl (2E,4Z)-deca-2,4-dienoate in fruit under ULO storage. Although synthesis of aroma volatiles was most suppressed under ULO at −1°C, butyl and hexyl acetate levels recovered better in fruit under ULO storage at −1°C than at +1°C. Acetaldehyde and nonanal were the principal aldehydes present, with levels that were higher in early harvested fruit and in fruit stored at +1°C. Using multivariate analysis, we found two clusters one for after storage and the other for after shelf life samples, with the exception of pears after storage and after shelf life at +1°C and normal atmosphere positioned on the lower side of graph Overall, this analysis discriminated between mentioned storage conditions that are specifically defined by hexylacetate and decanal on the one side and ethyl butanoate, pentyl acetate and α-farnesene on the other side.

Solid state supramolecular structure of diketopyrrolopyrrole chromophores: correlating stacking geometry with visible light absorption

Mono- and di-alkylated 1,4-diketo-3,6-dithiophenylpyrrolo[3-4-c]pyrrole derivatives (TDPPs) have been synthesised and their solid state packing and absorption properties have been correlated. In this library of compounds the bulkier substituents distort the geometry of the chromophores and shift the lowest energy absorption band as a consequence of reduced π–π stacking and inter-chromophore overlap. Longitudinal displacement of the conjugated core is affected by donor–acceptor intermolecular interactions and twisting of the thiophene ring out of the plane of the DPP core, whereas lateral displacement was correlated to distortion of the NLactam–C(R) bond out of the plane of the DPP core. The di-substituted TDPP with hexyl units exhibit high molecular planarity, strong close packing of the conjugated core and significant red shift of the maximum of absorption in the solid, whereas the mono-substituted compounds with hexyl and ethyl acetate units are the least distorted of the series because of strong intermolecular hydrogen bonding that increases the molecular overlap and planarity of the chromophores. Therefore the family of mono-substituted TDPPs and more specifically the ones with ethyl acetate substituents show good potential for modulating the molecular geometry and optimizing the charge transport in materials for organic electronic applications.

Analysis of volatile compounds of clove (syzygium aromaticum) buds as influenced by growth phase and investigation of antioxidant activity of clove extracts

AbstractThe volatile compounds originating from fresh clove (Syzygium aromaticum) buds cultivated in a medicinal plant garden located in southern Tokyo were investigated. The volatile compounds originating from fresh clove buds were adsorbed onto polydimethylsiloxane‐coated devices and then analysed using gas chromatography‐mass spectrometry. Sampling was performed at three different development stages of clove buds, i.e., phase I (green), phase II (pink), and phase III (red). In thermal desorption‐gas chromatography‐mass spectrometry procedure volatile compounds: eugenol, β‐caryophyllene, α‐humulene, α‐farnesene, and eugenol acetate were the predominant constituents in most cases. Methyl salicylate, α‐copaene, β‐ocimene, 2‐nonanone, ethyl hexanoate, and acetophenone were additionally found as the buds ripened. Volatile compounds obtained from clove leaves were analysed using the same method, and β‐caryophyllene, eugenol, α‐humulene, 3‐hexen‐1‐ol, 3‐hexen‐1‐yl acetate, and hexyl acetate were identified.The antioxidant activity of both water and methanol extracts of clove buds and leaves collected from the medicinal plant garden was confirmed using electron spin resonance spectrometry. Scavenging activities against superoxide anion radical and hydroxyl radical were evaluated. Copyright © 2015 John Wiley &amp; Sons, Ltd.

1-methylcyclopropene effects on volatile profile and quality of 'Royal Gala' apples produced in Southern Brazil and stored in controlled atmosphere

ABSTRACT: Apple volatile aroma depends of complex interaction among organic compounds. The aim of the present study was to evaluate the effect of 1-methylcyclopropene (1-MCP) application on volatile profile and quality on 'Royal Gala' apples produced in Southern Brazil and stored under controlled atmosphere condition (CA; 1.0kPa O2+1.2kPa CO2; 0.5±0.1°C; 94±1% relative humidity). Volatile profile was determined after eight month of CA storage plus 7 days of shelf life via solid-phase microextraction (HS-SPME) and analyzed by gas chromatography coupled to mass spectrometer. In the volatile profile were identified 8 esters, 11 alcohols, 6 aldehydes, 6 acids, 2 ketones, 1 ether and 1 terpene. 1-MCP application reduced significantly the main volatile compounds production by 'Royal Gala' apples produced in Southern Brazil. Its application decreases significantly the esters production, especially 2-methyl-butyl acetate and hexyl acetate, compared to 'Royal Gala' apples storage under CA. 1-methylcyclopropene application decrease ethylene production and respiration rate. Apples treated with 1-MCP exhibit higher hexanal and 2(E)-hexenal production.

A pecky rice-causing stink bug Leptocorisa chinensis escapes from volatiles emitted by excited conspecifics

The stink bug Leptocorisa chinensis (Hemiptera: Alydidae), which causes pecky rice grains, emits pungent volatiles when disturbed. To study ecological functions of the volatiles, we investigated the responses of adult L. chinensis in a small observation arena. When an undisturbed individual of the same gender was introduced into the arena, the initially occupying L. chinensis did not show any behavioural responses. However, when a disturbed conspecific of the same gender was introduced, the initial occupant was excited immediately and escaped from the arena through the hole, suggesting that the pungent volatiles from a disturbed conspecific caused excitement/escape behaviour. Chemical analyses using a gas chromatograph–mass spectrometer showed that disturbed adults of both sexes emitted octanal, (E)-2-octenal, octanol, hexyl acetate, (Z)-3-octenyl acetate, octyl acetate and (E)-2-octenyl acetate. (E)-2-Octenal was the major compound. When exposed to (E)-2-octenal and to (E)-2-octenyl acetate, undisturbed females were excited and escaped from the observation arena with a similar proportional response as to disturbed females. Males and females escaped from (E)-2-octenal at ca. 2–10 ppbV in a mesh cage. The possible use of the volatile compounds eliciting excitement/escape behaviour in L. chinensis for control of this species in paddy fields is discussed.

Volatile Characterization of Major Apricot Cultivars of Southern Xinjiang Region of China

The characterization of aroma of the 14 main apricot (Prunus armeniaca L.) cultivars in Xinjiang was evaluated using high-performance solid-phase microextraction (HP-SPME) with gas chromatography-mass spectroscopy (GC-MS). A total of 208 volatiles that include 80 esters, 25 aldehydes, 15 terpenes, 21 ketones, 39 alcohols, 27 olefins, and 1 acid were identified from these cultivars. The compounds propyl acetate, 3-methyl-1-butanol acetate, (Z)-3-hexen-1-ol acetate, d-limonene, β-linalool, hexanal, hexyl acetate, butyl acetate, β-myrcene, ethyl butanoate, and β-cis-ocimene were the major compounds responsible for aroma in these cultivars. GC-MS results showed that Kuchexiaobaixing, Guoxiyuluke, and seven other cultivars were characterized by a high level of esters and were considered to be fruity apricot aroma. ‘Luotuohuang’ and ‘Heiyexing’ accumulate high levels of terpenes and exhibited an outstanding floral aroma. Higher levels of alcohols and aldehydes were observed in ‘Danxing’, ‘Sumaiti’, and ‘Kumaiti’. The latter are considered green aroma cultivars. These three types of cultivars with different aroma characteristics can be significantly differentiated by using the principal component analysis (PCA) method. The contributions of volatiles to the apricot aroma were assessed by using the partial least squares regression (PLSR) model. Esters, terpenes, and C6 components were shown to be responsible for the fruity, floral, and green character of fresh apricots, respectively.

2단계 발효로 제조된 고산도 사과식초의 품질지표성분 설정

In this study, high-acidity cider vinegar (HACV) was produced by alcoholic and acetic acid fermentation of apple concentrate without any nutrients and then the optimum alcohol concentration was determined through a qualitative study. HACV was fermented with different initial alcohol concentrations (6-9%) during the process of acetic acid fermentation. The highest content of reducing sugar, organic acids, and free amino acids was observed at 6% of initial alcohol concentration. Approximately 20 types of volatile compounds were identified by solid-phase microextraction (SPME) and GC-MS. The total volatile content was the highest at 6% of initial alcohol concentration, and the acid content was the lowest at 9% of the initial alcohol concentration. The HACV produced by a two-stage fermentation process was qualitatively better than commercial HACV presenting the highest value at 6% of initial alcohol concentration. Malic acid, aspartic acid, and hexyl acetate were selected as quality index components of HACV production by two-stage fermentation on the basis of correlation between their physicochemical properties and the sensory attributes of HACV.

Identification of the Alarm Pheromone of Hygia lativentris and Changes in Composition during Development.

Heteropteran insects produce a series of volatile compounds from their scent glands that protect them from predators and parasites. These compounds also play roles in chemical communication that elicit aggregation, dispersal, and mating behaviors. Hygia lativentris (Coreidae) adults frequently aggregate on host plants. When disturbed, they quickly disperse with the release of a sour smell, suggesting that these bugs possess an alarm pheromone in their secretions. This adult secretion-induced dispersal has been examined with a laboratory assay. Hexanal, the predominant component of the adult secretion was identified as a component of the alarm pheromone by evaluation of the adult bug's response time and escape distance from the chemical source. Physicochemical analyses with gas chromatography/mass spectrometry and nuclear magnetic resonance spectroscopy revealed that secretory components differed between nymphs and adults, and also during adult aging. Nymphs produced two unsaturated compounds, (E)-2-hexenal and (E)-4-oxo-2-hexenal, together with hexanal and 1-hexanol, which were found in all developmental stages. In adults, hexyl acetate was the major component of secretions within 3 days of emerging, while the amount of this ester decreased and those of hexanal, hexanoic acid, and hexanal trimer increased with aging. The decomposition of hexyl acetate into hexanal via 1-hexanol was attributed to the presence of esterases and alcohol dehydrogenases specifically found in adult secretory glands. In contrast, the formation of a hexanal trimer may be due to a non-enzymatic reaction under acidic conditions.

Amperometric Detection of Plant Volatiles Using Metal Oxide Nanoparticles

Volatile organic compounds released by pathogen-infected plants can be used as fingerprints for plant disease detection via electronic nose technologies1,2. In this work, nanoparticles of TiO2 or SnO2 modified on screen-printed carbon (SP) electrodes have been developed for detection of fruit volatiles using amperometric techniques. p-ethylguaiacol, is a characteristic compound present in the volatile signature of fruits infected with a pathogenic fungus called Phytophthora cactorum. The electroanalytical data obtained using cyclic voltammetry and differential pulse voltammetry showed that both SnO2 and TiO2 exhibited high sensitivity (174–188 mA cm-2 mM-1) and low detection limits (35–62 nM) for p-ethylguaiacol detection3. Both biosensors were evaluated for interference by adding common green leaf volatiles (cis-3-hexel-1-ol, hexyl acetate and cis-3-hexen-1-yl acetate). The results demonstrate that both metal oxides are a reasonable alternative to expensive electrode materials such as gold or platinum for amperometric sensor applications. Reference T. Baldwin, A. Kessler and R. Halitschke, Curr. Opin. Plant Biol., 2002, 5, 351.P. W. Par´e and J. H. Tumlinson, Plant Physiol., 1999, 121, 325.Y. Fang, Y. Umasankar and R. P. Ramasamy, Analyst., 2014, 139, 3804 Figure 1

Olfactory response of Anastrepha striata (Diptera: Tephritidae) to guava and sweet orange volatiles.

The behavioral responses of virgin and mated female Anastrepha striata Schiner (Diptera: Tephritidae) to guava (Psidium guajava L.) or sweet orange (Citrus sinensis L.) were evaluated separately using multilure traps in two-choice tests in field cages. The results showed that flies were more attracted to guava and sweet orange volatiles than to control (unbaited trap). The physiological state (virgin or mated) of females did not affect their attraction to the fruit volatiles. Combined analysis of gas chromatography coupled with electroantennography (GC-EAD) of volatile extracts of both fruits showed that 1 and 6 compounds from orange and guava, respectively elicited repeatable antennal responses from mated females. The EAD active compounds in guava volatile extracts were identified by gas chromatography-mass spectrometry (GC-MS) as ethyl butyrate, (Z)-3-hexenol, hexanol, ethyl hexanoate, hexyl acetate, and ethyl octanoate. Linalool was identified as the only antennal active compound in sweet orange extracts. In field cage tests, there were no significant differences between the number of mated flies captured by the traps baited with guava extracts and the number caught by traps baited with the 6-component blend that was formulated according to the relative proportions in the guava extracts. Similar results occurred when synthetic linalool was evaluated against orange extracts. From a practical point of view, the compounds identified in this study could be used for monitoring A. striata populations.

Monitoring the evolution of volatile compounds using gas chromatography during the stages of production of Moscatel sparkling wine

This study reports, for the first time, the main changes that occur with some important aroma compounds of Moscatel sparkling wines during winemaking, measured using headspace solid-phase microextraction, one-dimensional and comprehensive two-dimensional gas chromatography (GC×GC) with mass spectrometry detection (MS). The best conditions of volatile extraction included the use of PDMS/DVB fibre, 2mL of wine, 30% of NaCl, 40°C for 30min. The chromatographic profile of sparkling wines showed decreasing amounts of monoterpenes (limonene, 4-terpineol, terpinolene, citronellol, α-terpineol, linalool, hotrienol, and nerol oxide), increasing amounts of esters (terpenyl esters, ethyl octanoate, ethyl decanoate and hexyl acetate) and alcohols (1-nonanol and 2-phenylethanol). Sixty-nine compounds co-eluted in the first dimension; only six co-eluted in the second dimension. GC×GC/TOFMS allows more detailed study of the volatile profile of sparkling wines.

Volatile profile of yellow passion fruit juice by static headspace and solid phase microextraction techniques

The profile of volatile compounds of yellow passion fruit juice was analyzed by solid phase microextraction headspace (HS-SPME) and optimized static headspace (S-HS) extraction techniques. Time, temperature, NaCl concentration and sample volume headspace equilibrium parameters was adjusted to the S-HS technique. The gaseous phase in the headspace of samples was collected and injected into a gas chromatograph coupled to a mass spectrometer. In the HS-SPME technique was identified 44 volatile compounds from the yellow passion fruit juice, but with S-HS only 30 compounds were identified. Volatile esters were majority in both techniques, being identified ethyl butanoate, ethyl hexanoate, (3z)-3-hexenyl acetate, hexyl acetate, hexyl butanoate and hexyl hexanoate. Aldehydes and ketones were not identified in S-HS, but were in HS-SPME. β-Pinene, p-cymene, limonene, (Z)-β-ocimene, (E)-β-ocimene, γ-terpinene, α-terpinolene and (E) -4,8-dimethyl-1, 3,7 - nonatriene terpenes were identified in both techniques. This study showed that the S-HS optimized extraction technique was effective to recovery high concentrations of the major volatile characteristics compounds in the passion fruit, such as ethyl butanoate and ethyl hexanoate, which can be advantageous due to the simplicity of the method.

Liquid–liquid equilibria of water + acetic acid + 2-ethyl hexyl acetate ternary system

Liquid–liquid equilibrium (LLE) data of water+acetic acid+2-ethyl hexyl acetate have been determined experimentally at 298.2, 308.2 and 318.2K. All the phase diagrams were obtained by determining binodal curves and tie-lines. The reliability of the experimental tie-lines was confirmed by using the Othmer–Tobias correlation. UNIFAC and modified UNIFAC models were used to predict the phase equilibrium in the system determined from experimental data, using the interaction parameters between CH3, CH2, CH, CH3COO, COOH, and H2O functional groups. Distribution coefficients and separation factors were evaluated for the immiscibility region.