Methyl Ester Fraction Research Articles

Efficient rapid fractionation of fatty acid methyl esters (FAMEs) through evaporative urea inclusion

FAMEs work as an alternative to petroleum-based diesel fuels for its low carbon footprint. However, FAMEs' qualities are constrained by the sources' fatty acid profiles. Fractionation of FAMEs can significantly change biodiesel's qualities. Compared to other fractionation methods, evaporative urea inclusion fractionation can rapidly and effectively separate the saturated FAMEs. In addition, FTIR analysis indicated the possible conjugation of host structures by unstable hydrogen bonding and oxygen bonding. Crystallite sizes and strain of urea inclusion compounds (UICs) were calculated from the XRD spectrum, influenced by FAMEs' structures and operation processes. Only the ratios of urea to FAMEs can significantly affect compositions in evaporative urea inclusion fractionation. However, UICs formation rates were influenced by all operation conditions, such as temperatures, pressures, and ratios of urea to FAMEs to solvent. The products were evaluated by the low-temperature performance, cetane number, oxidation stability, energy density, and emissions. Urea inclusion fractionation can significantly improve the low-temperature performance, the major constraint for enlarging the utilization. However, the decreased cetane number and oxidation stability indicated the possible need for antioxidants and cetane improvers after urea inclusion fractionation. Moreover, the unsaturated enriched products from urea inclusion fractionation can provide the feedstock to synthesize biochemical or biomaterials, such as carboxylic acids, polyesters, and biolubricants.

Modeling of separation of fatty acid methyl esters derived from fisheries waste by urea complexation method

The aim of the study is to develop a simulation model for the fractionation of fatty acid methyl esters (FAME).by urea complexation. The fatty acids (FAs) were obtained from squid liver and scallop mid-gut, which contain rich in eicosapentaenoic and docosahexaenoic acids well known as health-promoting FAs. FAs can be divided into saturated fatty acid (SFA), monounsaturated fatty acid (MFA), and polyunsaturated fatty acid (PFA) based on the number of double bond in their structure. A fractionation model is proposed and derived from the assumption of the urea-FAMEs complexation reactions, which included equilibrium constants (K) concerned with FAMEs-urea and urea-urea binding. The experiments were conducted at 5 and 28 °C. Different complexation behaviors were observed for SFAME, MFAME, and PFAME. The amount of SFAME captured in the urea inclusion body was larger than MFAME and PFAME. The urea-SFAME and urea-MFAME formation behavior agreed very well with the proposed model, but the urea-PFAME formation behavior showed a large error with the calculation results. The validation experiments showed that the relative error between the experimental data and the model prediction was within 15% for SFAME and MFAME.

Fractionation of fatty acid methyl esters via urea inclusion and its application to improve the low-temperature performance of biodiesel

Biodiesel is viewed as the alternative to petroleum diesel, but its poor low-temperature performance constrains its utilization. Cloud point (CP), the onset temperature of thermal crystallization, appropriately shows the low-temperature performance. The effective way to reduce CP is to remove saturated fatty acid methyl esters (FAMEs). Compared to current methods, this work describes an extraordinary approach to fractionating FAMEs by forming solid urea inclusion compounds (UICs). Urea inclusion fractionation reduces the CPs by removing high melting-point linear saturated FAME components. Urea inclusion fractionation in this study was performed under various processing conditions: mass ratios of urea to FAMEs and solvents to FAMEs, various solvents, FAMEs from various feedstocks, and processing temperatures. Supersaturation of urea in the solution is the driving force, and it significantly affects yield, composition, CP, separation efficiency, and selectivity. Through a single urea inclusion fractionation process, FAMEs, except palm oil FAMEs, resulted in CP reduction ranging from 20 to 42 oC with a yield of 77–80% depending on the compositions. CP of palm oil FAMEs could reach as low as -17 oC with a yield of 46% after twice urea inclusion fractionation. According to the model prediction, the cetane number after urea inclusion fractionation decreased about 0.7–2 but was still higher than the minimum biodiesel requirement. Oxidation stability after urea inclusion decreased according to the proposed model, but this can be mitigated by adding antioxidants. Emission evaluation after urea inclusion fractionation indicated decreased hydrocarbons, carbon monoxide, and particulate matter. However, it resulted in the increasing emission of nitrogen oxides.

Combustion characteristics of sugar apple seed (Annona squamosa) oil methyl ester and its blends on compression ignition engine

ABSTRACT In this present investigation, sugar apple seed (Annona squamosa) oil methyl ester (SASOME) is selected for test on the diesel engine and its suitability as an alternative fuel is examined. The viscosity of the SASOME is reduced by blending with diesel in the proportion of 25/75%, 50/50%, 75/25% and 100/0% on volume basis, then compared with diesel fuel. The aim of this study is to examine the effect of fraction of methyl ester in the blends on performance, emission and combustion parameters. The 50% blend shows 6.68% increase in BTE compared to diesel fuel. The reduction in UBC and CO is observed with 50% blend along with increased NO x emissions compared to diesel fuel. The results show the higher value of cylinder pressure, net heat release rate, cumulative heat release rate, mean gas temperature, mass fraction burned and rate of pressure rise with 50% blend compared to that of diesel fuel. Abbreviations: CHRR, cumulative heat release rate; CO, carbon monoxide; CP, cylinder pressure; HBC, unburnt hydrocarbons; MFB, mass fraction burned; MGT, maximum gas temperature; NHRR, net heat release rate; NO x , oxides of nitrogen; RPR, rate of pressure rise; SASOME, sugar apple seed oil methyl ester; %, percentage

Utilizing of CaO catalyst from chicken eggshells at several concentrations to produce biodiesel based on moringa seed oil

Chicken eggshells contain a high concentration of CaCO3 compounds, which are potentially transformed to CaO by calcination method. CaO has been used as a heterogeneous catalyst for biodiesel or fatty acid methyl ester production from Moringa seed oil. The purpose of this study is to determine the percentage of CaO which produces the highest methyl ester mass fraction and to find out the characteristics of the biodiesel. Biodiesel was made through a transesterification reaction by using a CaO catalyst that has been calcined at 900°C for 2 hours. This study was conducted using a completely randomized design (CRD) with the independent variable in the form of CaO mass percentages consisting of 5 levels (1, 2, 3, 4, and 5%). CaO catalyst at 3% concentration resulted in a mass fraction of methyl ester of 57.1%. Characteristics of the biodiesel contained water content of 0.3%, acid number of 0.03 mg KOH/g, saponification number of 6.93 mg KOH/g, iodine number of 5.49 g iod/100g, cloud point of 18°C, and pour point of 16°C. Some of the characteristics have fulfilled the standardizations of ASTM and SNI.

One-path catalytic supercritical methanothermal production of fatty acid methyl ester fractions from wet microalgae Chlorella vulgaris

Biodiesel production from microalgae requires energy-intensive dewatering before lipid extraction and transesterification. In order to avoid this energy penalty, one-path direct transesterification of wet microalgae (Chlorella vulgaris) using supercritical methanol is attempted, for the first time with added heterogeneous catalysts. This methanothermal process was found to be robust, maintaining high fatty acid methyl ester (FAME) fraction yields in a wide range of water content (16–64 mol % water in methanol). Among the eight metal oxide catalysts tested, α-Al2O3 showed the best performance for the reaction, producing 1.4–1.6 times as much FAME fractions compared to non-catalytic reaction in the same moisture range. The present catalysis is found to be not affecting transesterification step, evidenced by the weak effect of surface acidity. Instead, it appears to add extra routes to produce fuel components that fall in the FAME fraction range.

Microbial characterization of a facultative residual sludge obtained from a biogas plant with ability to degrade commercial B10 diesel oil

Biodegradation of commercial B10 diesel oil (DB10) by the microbial consortium present in a biogas residual sludge was first investigated. Maximum removal efficiencies of the petrochemical and fatty acids methyl ester (FAME) fractions of DB10 were 55 ± 3% and 94 ± 6%, respectively. Taxonomic profiling of the microbial consortium present in the residual sludge was carried out in order to identify potential hydrocarbon-degrading bacteria. After mild selection pressure using DB10, three Pseudomonas species (P. aeruginosa, P. stutzeri and P. mendocina) were mostly found in the treated sample. However, only P. aeruginosa and P. stutzeri showed a rapid growth and high dehydrogenase activity at the expense of DB10 as the sole carbon source. In addition, both strains removed 42 ± 5% and 53 ± 2% of the petrochemical fraction, and >75% of the FAME fraction, respectively. Similar results were found with a bacterial consortium of the three isolated Pseudomonas, indicating no synergistic hydrocarbon degradation by these strains. As expected, biosurfactant production by the pseudomonads was directly associated with the bacterial DB10 biodegradation performance. These results are the first describing petroleum-based hydrocarbon biodegradation ability of a crude facultative residual sludge obtained from a biogas facility; and represent a rational first step in order to understand which bacteria in the sludge may act in petroleum-based fuels degradation.

Inhibition of the pro-inflammatory mediators in rat neutrophils by shanzhiside methyl ester and its acetyl derivative isolated from Barleria prionitis.

The aerial parts of Barleria prionitis Linn. (BP) (Acanthaceae) plant has long been used to treat inflammatory disorders such as toothache, swellings, arthritis and gout. The purpose of this study was to evaluate the effects of shanzhiside methyl ester (SME), 8-O-acetyl shanzhiside methyl ester (ASME) and iridoid glycosides rich monoterpenoidal fraction (IFBp), isolated from the aerial part of BP, on the pro-inflammatory mediators in stimulated rat neutrophils. Rat neutrophils were incubated with or without test drugs. The influence of laboratory isolated and identified SME, ASME and IFBp on the production and release of pro-inflammatory mediators i.e. myeloperoxidase (MPO), elastase, matrix metalloproteinase-9 (MMP-9), interleukin 8 (IL-8), tumor necrosis factor alpha (TNF-α) and leukotriene B4 (LTB4) was evaluated in the formyl-met-leu-phenylalanine (f-MLP) and lipopolysaccharide (LPS) stimulated rat neutrophils using enzyme-linked immunosorbent assay (ELISA) methods. IFBp was also standardized with the high performance thin layer chromatography by simultaneous determination of SME and ASME marker compounds. SME, ASME and IFBp displayed concentration-dependent inhibitory effects on the MPO, elastase and MMP-9 enzymes release, and IL-8, TNF-α and LTB4 cytokines production in the f-MLP and LPS stimulated rat neutrophils. The content of SME and ASME was found to be 17.32 ± 1.98 and 11.30 ± 1.06% w/w, respectively, in IFBp by HPTLC method. Altogether, the present results suggest that the iridoidal glycosides of BP may be considered as therapeutic strategy against neutrophil-mediated inflammatory diseases. Developed and validated HPTLC method for the standardization of IFBp of BP can be used as a quality control tool for the routine qualitative and quantitative analysis of Barleria species containing SME and/or ASME.

Investigation of Physico-Chemical Properties of Simaruoba Methyl Ester and Diesel Blends

This paper presents the experimental study of physico-chemical properties of Simarouba methyl ester and diesel blends at the different temperatures and with varying volume percentage of Simarouba methyl ester in the blend. Blends are prepared adding different volume fraction of Simarouba methyl ester to neat diesel. The percentage of Simarouba methyl ester added to diesel is 10% to 90%, the prepared blends are stirred well for mixing of methyl ester and diesel. The prepared blends are kept in closed container for 24 hours for observation of separation of blends. It is observed that there is no separation of Simarouba methyl ester and diesel. Experiments are carried out to find density, kinematic viscosity, flash point and heating value of blends. These properties are investigated using standard equipments with standard procedure. Viscosity is determined by using standard Red-Wood viscometer with standard procedure of methyl ester and diesel blends at different temperatures. It is observed that as volume fraction of Simarouba methyl ester increases in the blend density, kinematic viscosity, flash point increases and heating value decreases. The percentage decrease in kinematic viscosity is more at lower temperature compared to higher temperature. Correlations for estimation of viscosity and density of blends at different temperatures are proposed.

Home-made silver ion solid-phase extraction system for the analysis of trans fatty acids: comparison with commercial Discovery Ag-Ion SPE

A home-made silica-based silver ion solid-phase extraction (Ag+-SPE) system for the fractionation and subsequent gas chromatographic analysis of trans fatty acids in human adipose tissue is developed and examined. Analytical characteristics of the home-made Ag+-SPE column were compared with those of the commercial Discovery Ag-Ion SPE column and it was demonstrated that the both columns can be applied for the fractionation of fatty acid methyl esters.

Production of lutein, and polyunsaturated fatty acids by the acidophilic eukaryotic microalga Coccomyxa onubensis under abiotic stress by salt or ultraviolet light

In this study, the effect of abiotic stress on the acidophilic eukaryotic microalga, Coccomyxa onubensis, was analyzed for the production of lutein and PUFAs (polyunsaturated fatty acids). It grows autotrophically at a pH of 2.5. It showed a growth rate of 0.30 d-1, and produced approximately 122.50mg·L-1·d-1 biomass, containing lipids (300.39mgg-1dw), lutein (5.30mgg-1dw), and β-carotene (1.20mgg-1dw). The fatty acid methyl ester (FAME) fraction was 89.70mgg-1dw with abundant palmitic acid (28.70%) and linoleic acid (37.80%). The addition of 100mM NaCl improved the growth rate (0.54 d-1), biomass productivity (243.75mg·L-1·d-1), and lipids accumulation (416.16mgg-1dw). The microalga showed a lutein content of 6.70mgg-1dw and FAME fraction of 118.90mgg-1dw; 68% of the FAMEs were PUFAs. However, when 200-500mM salt was added, its growth was inhibited but there was a significant induction of lutein (up to 7.80mgg-1dw). Under continuous illumination with PAR (photosynthetically active radiations)+UVA (ultraviolet A, 8.7Wm-2), C.onubensis showed a growth rate of 0.40d-1, and produced 226.3mg·L-1·d-1 biomass, containing lipids, (487.26mgg-1dw), lutein (7.07mgg-1dw), and FAMEs (232.9mgg-1dw); 48.4% of the FAME were PUFAs. The illumination with PAR+UVB (ultraviolet B, 0.16Wm-2) was toxic for cells. These results indicate that C.onubensis biomass is suitable as a supplement for functional foods and/or source of high added value products.

Furan fatty acid content and homologue patterns of fresh green matrices

Furan fatty acids (furan-FAs) are valuable antioxidants which are supposed to play an important role in the protection of polyunsaturated fatty acids from getting oxidised. Scattered literature reports indicated that these fatty acids are widely present at low concentrations in various biological and food samples. Here, we determined the furan-FA composition in 35 samples including seven fresh herb matrices, as well as in spinach and grass. Samples were transesterified and furan-FAs were enriched from the fatty acid methyl ester fraction by means of silver ion chromatography followed by analysis with gas chromatography with mass spectrometry operated in selected ion monitoring mode (GC/MS-SIM). The samples featured between one (rosemary) and eight different furan-FAs (curly-leaf parsley). Six saturated and four unsaturated furan-FAs were identified with clear dominance of β,β’-dimethyl-substituted representatives. The total amount of furan-FAs ranged from 15 to 2650 μg/100 g fresh weight with dill, grass and curly-leaf parsley being the richest sources among the sample matrices. The rarely described unsaturated furan-FAs were detected in eight of the nine matrices and were predominant in flat-leaf parsley. Curly-leaf and flat-leaf parsley as well as fresh and deep-frozen spinach samples showed remarkable differences in the furan-FA pattern.

Effect of Sulfur Content on Microbial Composition and Biodegradation of a Brazilian Diesel and Biodiesel Blend (B10)

Environmental legislation has driven the reduction of sulfur levels in automotive fuels worldwide (≤10 ppm). We evaluate the behavior of microbial biomass in terms of community composition, metabolite production, and degradation of the Brazilian blend B10, made with ultra-low-sulfur diesel (ULSD, 6.3 ppm), high-sulfur diesel (HSD, 327 ppm), and ultra-high-sulfur diesel (UHSD, 861 ppm) during simulated storage. The microcosm was assembled in glass flasks containing an aqueous phase (mineral medium) and an oil phase (fuels) at two conditions of microbial contamination: natural (∼103 colony-forming units (CFU) per liter ) and inoculated (∼106 bacterial cells and fungal spores per milliliter), evaluated each 10 days for 40 days. The results showed that biomass production was more pronounced in inoculated treatment and could be described at T40 as UHSD < ULSD < HSD B10. The higher degradation of terminal methyl ester fraction (50 ± 1%), and aromatic compounds (46 ± 2%) was in HSD B10, and ULSD B10 suffered the...

Effects of Aerobic Growth on the Fatty Acid and Hydrocarbon Compositions of Geobacter bemidjiensis BemT.

Geobacter spp., regarded as strict anaerobes, have been reported to grow under aerobic conditions. To elucidate the role of fatty acids in aerobiosis of Geobacter spp., we studied the effect of aerobiosis on fatty acid composition and turnover in G. bemidjiensis BemT. G. bemidjiensis BemT was grown under the following different culture conditions: anaerobic culture for 4 days (type 1) and type 1 culture followed by 2-day anaerobic (type 2) or aerobic culture (anaerobic-to-aerobic shift; type 3). The mean cell weight of the type 3 culture was approximately 2.5-fold greater than that of type 1 and 2 cultures. The fatty acid methyl ester and hydrocarbon fraction contained hexadecanoic (16:0), 9-cis-hexadecenoic [16:1(9c)], tetradecanoic (14:0), tetradecenoic [14:1(7c)] acids, hentriacontanonaene, and hopanoids, but not long-chain polyunsaturated fatty acids. The type 3 culture contained higher levels of 14:0 and 14:1(7c) and lower levels of 16:0 and 16:1(9c) compared with type 1 and 2 cultures. The weight ratio of extracted lipid per dry cell was lower in the type 3 culture than in the type 1 and 2 cultures. We concluded that anaerobically-grown G. bemidjiensis BemT followed by aerobiosis were enhanced in growth, fatty acid turnover, and de novo fatty acid synthesis.

Quantitative Analysis of the Distribution of cis-Eicosenoic Acid Positional Isomers in Marine Fishes from the Indian Ocean.

This study investigated the occurrence and distribution of cis-eicosenoic acid (c-20:1) positional isomers in fishes from the Indian Ocean and compared to those from the Pacific and Atlantic Ocean. Lipids were extracted from the edible part of the fish and then methylated. The eicosenoic acid methyl ester fraction was separated from total fatty acid methyl esters by reversed-phase HPLC and quantitatively analyzed using a GC-FID fitted with the SLB-IL111 highly polar GC column. c14-20:1 was used as an internal standard. The results indicated that the highest levels of c-20:1 positional isomers were found in fishes from the Pacific Ocean (saury, 166.95±12.4 mg/g of oil), followed by the Atlantic Ocean (capelin, 162.7±3.5 mg/g of oil), and lastly in fishes from the Indian Ocean (goatfish, 34.39 mg/g of oil). With only a few exceptions, the most abundant 20:1 positional isomer found in fishes of the Indian and Atlantic Ocean was the c11-20:1 isomer (>50%) followed by the c13-20:1 isomer (<25%). Unusually, the c7-20:1 isomer was predominantly found in a few fishes such as the tooth ponyfish, longface emperor, and commerson's sole. The c9, c5, and c15-20:1 isomers were the least occurring in fishes from the Indian and Atlantic Ocean. In contrast, the c9-20:1 isomer was the principal isomer identified in fishes from the Pacific Ocean. The results revealed that the content and distribution of c-20:1 positional isomers varied among fishes in different oceans. The data presented in the current study are the first to report on the distribution of c-20:1 positional isomers in fishes from the Indian Ocean.

English

This paper concerns the production of methyl laurate from coconut cream through fractionation of methyl esters. Coconut oil was produced by wet processing of coconut cream. The esters were prepared by reacting coconut oil and methanol using homogeneous catalyst KOH in a batch reactor, followed by fractionation of fatty acid methyl esters (FAME) at various reduced pressures applying differential batch vacuum distillation. Experimental data were compared with simulation of a batch distillation employing the simple Raoult’s model and modified Raoult’s model of phase equilibria. Activity coefficients (γ i ) were determined by optimization to refine the models. The modified Rault’s model with activity coefficients gave better agreement with the experimental data, giving the value of γ i between 0,56-0,73. For a given boiling temperature, lower operating pressure produced higher purity of C10 and C12 FAME for respective distillates.

The role of the glucuronoxylan carboxyl groups in the action of endoxylanases of three glycoside hydrolase families: A study with two substrate mutants

BackgroundBacterial appendage-dependent GH30 glucuronoxylan hydrolases recognize the substrate through an ionic interaction of a conserved positively charged arginine with the carboxyl group of 4-O-methyl-d-glucuronic acid. One of the options to verify this interaction is preparation of enzyme mutants. An alternative approach is a chemical modification of the substrate, glucuronoxylan, in which the free carboxyl group in all residues of MeGlcA is eliminated. MethodsIn this work the carboxyl groups of 4-O-methyl-d-glucuronic acid residues of an alkali extracted beechwood xylan were esterified with methanol. A water-soluble fraction of the polysaccharide methyl ester was converted by NaBH4 reduction to the second soluble derivative, 4-O-methylglucoxylan. Specific activities of several endoxylanases (EXs) of GH families 10, 11 and 30 were determined on glucuronoxylan, and its two new uncharged derivatives. ResultsElimination of the free carboxyl group from the polysaccharide did not influence activities of GH10 EXs, but resulted in 50% decrease of specific activity of GH11 EXs, and led to more than 300-fold reduction of specific activity of Erwinia chrysanthemi GH30 xylanase. ConclusionsThese results confirm the crucial role of the interactions between GH30 xylanases and the MeGlcA carboxyl group for efficient cleavage of the polysaccharide. Analysis of the hydrolysis products by TLC and MS confirmed that all three types of xylanases hydrolyzed uncharged glucuronoxylans similarly as the original one. SignificanceThe uncharged glucuronoxylan derivatives will be useful to differentiate GH30 xylanases with various degree of selectivity for glucuronoxylan, including fungal enzymes without the conserved arginine.

Characterization of Mycolic Acids in Total Fatty Acid Methyl Ester Fractions from Mycobacterium Species by High Resolution MALDI-TOFMS.

Mycolic acids (MAs) are characteristic components of bacteria in the suborder Corynebacterineae, such as Mycobacterium. MAs are categorized into subclasses based on their functional bases (cyclopropane ring, methoxy, keto, and epoxy group). Since MAs have heterogeneity among bacterial species, analyzing of MAs are required in the chemotaxonomic field. However, their structural analysis is not easy because of their long carbon-chain lengths and several functional groups. In this study, total fatty acid (FA) methyl ester (ME) fraction of M. tuberculosis H37Rv was analyzed by matrix-assisted laser desorption/ionization (MALDI) time-of-flight mass spectrometry (TOFMS) with a spiral ion trajectory (MALDI spiral-TOFMS). The distributions of carbon-chain length and their relative peak intensities were confirmed with those obtained by analysis of each subclass fraction which was separated from total FA ME fraction using thin-layer chromatography (TLC). The observed major peaks were reliably assigned as MAs owing to the high mass accuracy (error<3 ppm). The types of MA subclasses, their distributions of carbon-chain lengths, their relative peak intensities, and the ratio of even- and odd-numbered carbon-chain MAs for the total FA ME fraction were consistent with those of MA subclass fractions. To visualize whole MAs, contour maps of relative peak intensities for whole MAs were created. The contour maps indicated the MA subclasses and their distributions of carbon-chains with relative peak intensities at a glance. Our proposed method allows simple characterization in a short time and thus enables the analysis of large numbers of samples, and it would contribute to the chemotaxonomy.

Microalgal fatty acid methyl ester a new source of bioactive compounds with antimicrobial activity

ObjectiveTo evaluate fatty acid composition and the antimicrobial activity of the major fraction of fatty acid methyl ester (FAME) extracts from three microalgae collected from freshwater lakes in Theni District, Tamil Nadu, India. MethodsAntimicrobial study was carried out by well diffusion method against bacterial as well as fungal pathogens such as Escherichia coli, Staphylococcus aureus, Enterobacter sp., Klebsiella sp., Salmonella typhi, Fusarium sp., Cryptococcus sp., Candida sp., and Aspergillus niger and Aspergillus flavus. The FAME profiles were determined through gas chromatography with a flame ionization detector. ResultsThe FAME was found to be radial effective in inhibiting the radial growth of both bacterial and fungal pathogens. The FAME extracts exhibited the antibacterial activity against three clinical pathogens, namely, Escherichia coli, Salmonella typhi and Enterobacter sp. with the maximum zone of inhibition of 12.0 mm, 12.0 mm and 11.0 mm, respectively. The FAME showed moderate antifungal activity against Cryptococcus sp. (11.8 mm), Aspergillus niger (10.5 mm), Candida sp. (11.8 mm) and Fusarium sp. (10.4 mm). Gas chromatography-flame ionization detector analysis revealed about 30 different FAMEs. ConclusionsWe assume that the observed antimicrobial potency may be due to the abundance of erucic acid methyl ester (C22:0), arachidic acid methyl ester (C20:0), palmitic acid methyl ester (C16:0), cis-11-eicosenoicmethyl ester (C20:1), cis-11, 14-eicosadienoic acid methyl ester (C20:2) and linolenic acid methyl ester (C18:3) in FAMEs which appears to be promising to treat microbial diseases.

Solvent‐Assisted Crystallization of Fatty Acid Alkyl Esters from Animal Fat

AbstractAn easy and efficient method for the separation of saturated and unsaturated fatty acid mono alkyl esters, prepared from animal fat, was developed. The most efficient separation was achieved by the use of solvents such as methanol and acetone at low temperatures. The dilution of the alkyl esters with 10 times the amount of solvent (10:1 v/w) and storage of the mixture for 4 h at −22 °C could be defined as optimum conditions. After filtration of the saturated fraction at the corresponding temperature very pure fractions were obtained. For fatty acid methyl esters deriving from tallow, with an initial content of saturated fatty acids of almost 50 %, a saturated ester fraction with only 5 % unsaturated fatty acids and an unsaturated ester fraction with about 9 % of saturated fatty acids could be obtained. The solvent easily could be recovered by distillation. In addition fatty acid ethyl, 1‐propyl, 2‐propyl, 1‐butyl, tert‐butyl and 3‐methyl‐1‐butyl esters were prepared and separated into saturated and unsaturated fractions. All fractions were analyzed according to the fatty acid compositions and showed similar or slightly worse results compared to the methyl esters. The cold filter plugging points of the unsaturated fractions were measured, showing the lowest value for the unsaturated methyl ester fraction at −26 °C. The fractionation with the use of solvents is an easy tool in order to obtain fatty acid alkyl esters with excellent cold temperature behavior out of animal fat.