Methyl Elaidate Research Articles

Mechanism of methyl elaidate on the thermal oxidation behavior

The effects of cis–trans isomerization on the oxidation products of oleic acid (composites and structure characterization) were investigated. The reduction of thermal oxidation reaction of methyl elaidate (ME) was 6.72 % lower than that of methyl oleate (MO), and the oxidation products (core aldehydes) first increased and then decreased with the prolongation of thermal oxidation time. ME exhibited better oxidation stability than MO in free radicals, hydroperoxides, double bonds, aldehydes, and glycerides. The oxidation products were mainly 11-oxo-9-undecenoate (initial stage) and methyl 9-oxononanoate (later stage), following the free radical chain reaction mechanism. The H8 in double bond was more easily dehydrogenated in the chain initiation stage than H11, followed by the formation of core aldehyde through three intermediates and two transition states each pathway. ME required a higher energy barrier (1.3–13.6 kJ/mol) than MO reaction, making it more difficult for ME to undergo thermal oxidation reaction. The transition state 4 and 5 were rate determining steps of chain initiation reaction and proliferation reaction, respectively. This study was of great significance to further control the formation of these trans fats and their oxidation products.

Esterification of crude tall oil catalyzed by Beta zeolite

In softwood Kraft pulping process, fatty/resin acids (extractives) react with the white liquor and are saponified, producing Tall Oil Soap (TOS). TOS can be converted back to the respective fatty/resin acids, generating Crude Tall Oil (CTO). In this work, TOS was converted into CTO according to standard methods, producing residual lignin and an aqueous phase as co-products. Then, CTO was esterified in the presence of Beta zeolites with different Si/Al ratios and particle sizes in rotary Teflon-lined stainless-steel autoclave. Compared to esterification of oleic and palmitic acids, esterification of CTO is a slow process, with conversions limited to no more than 83 % after 6 h at 393 K. Smaller particles (0.26 μm) and lower Si/Al ratio (15) showed greater conversion. This may be associated with a higher strength of Brønsted acid sites (due to lower Si/Al ratio) but also with an improved diffusion of reactants/products within zeolite micro- and mesopores (due to the relatively smaller particle size). The esterification product was mainly composed of esters of fatty acids, such as dimethyl 4-isopropyloctanedioate, methyl elaidate and methyl palmitate. Esters of resin acids (methyl abietate and dehydroabietate), phthalic acids, as well as paraffins are also present, but probably in lower concentrations.

Chemical components in the essential oils and ultrasonic extraction of amanus sage pholomis longifolia var. Longifolia boiss. & bl

In the present study the essential oil components of the flowers and leaves of Amanus sage Pholomis longifolia var. longifolia boiss. & Bl by ultrasonic extraction and steam distillation method were determined. According to the chemical composition analysis of Amanus Sage plant using ultrasonic extraction method, major components were methyl-7-octadecenoate (69.02%) and methyl elaidate (16.87%). The essential oil contents of flowers and leaves of the Amanus sage plant were also determined by steam distillation method. When the essential oil components of the flower were examined, the main components were found to be tricosane (22.39%), caryophyllene (22.17%), alpha-cubebene (14.4305), beta-farnesene (7.7%) and linalool (4.69%). On the other hand the main components in the the leaves were caryophyllene oxide (27.20%), fenchone (18.63%), 1,8-cineole (6.12%), camphor (4.82%), and alpha-cubebene (4.11%). Bioactive properties of the components of Amanus sage obtained from both the ultrasonic extraction and steam distillation methods showed that this plant has important medicinal and aromatic properties. Bangladesh J. Bot. 52(2): 799-803, 2023 (September)

Synthesis of Cu-1,4-Benzene Dicarboxylate Metal-Organic Frameworks (Cu-BDC MOFs) from Plastic Waste and Its Application as Catalyst in Biodiesel Production

The increasing of PET plastic waste causes various environmental problems because decomposing it is difficult to compose. This study aims to utilize PET plastic waste as a source of terephthalic acid organic linker in the solvothermal synthesis of Cu-1,4-Benzene Dicarboxylate metal-organic frameworks (Cu-BDC MOFs). Cu-BDC MOFs were characterized using FTIR, XRD, and SEM-EDX. The characterization results showed that the crystals of Cu-BDC MOFs had an irregular cubic morphology with an average crystal size of 67.96 nm. Furthermore, Cu-BDC MOFs were applied as catalysts for the esterification reaction to produce biodiesel from coconut oil. The conversion percentage of free fatty acids in the esterification process was 43.75 %, while in the transesterification process, it was 68.90 %. Analysis using GC-MS showed the presence of 8 peaks, with the largest percentage of areas identified as fatty acid methyl esters. The major components were methyl laurate (31.17 %), methyl myristate (18.77 %), methyl palmitate (12.50 %), methyl caprylate (10.76 %), methyl elaidate (10.07 %), methyl caprate (7.34 %), methyl stearate (5.67 %), and methyl linoleate (2.26 %). The quality of the biodiesel was tested, and the results were as follows: The density parameter was measured at 842.5 kg/m3, the viscosity measurement showed 2.9572 cSt, and the water content was found to be 0.09 %. Additionally, the acid number parameter was determined to be 0.2799 mg-KOH/g. HIGHLIGHTS Cu-BDC MOFs are produced through the hydrolysis of PET waste using a solvothermal mixture of distilled water, ethanol, and DMF at 85 °C for 24 h. The micrograph of the synthesized Cu-BDC MOFs reveals a clustered topography of Cu-BDC MOFs crystals with irregular cubic (hexahedral) shapes. FTIR analysis of biodiesel displays distinctive peaks corresponding to the -C-H, -C=O, -CH2, -CH3, and -C-O functional groups. The GC-MS analysis of biodiesel from coconut oil shows the presence of 8 major peaks, namely methyl caprylate, methyl caprate, methyl laurate, methyl myristate, methyl palmitate, methyl linoleate, methyl elaidate, and methyl stearate, with the largest percent area. The quality test results of biodiesel indicate a density parameter of 842.5 kg/m3, a biodiesel viscosity measurement of 2.9572 cSt, a water content of 0.0898 %, and an acid number of 0.2799 mg-KOH/g. GRAPHICAL ABSTRACT

Gas chromatography – mass spectrometry analysis of acetone extract of Lactuca tatarica (L.) C. A. Mey. roots

Research work is devoted to the chemical investigation of the roots of the Lactuca tatarica (L.) C. A. Mey. by gas chromatography – mass spectrometry method. From the crude extract that is obtained from the roots, the presence of natural compounds of various groups has been detected. As a result, 25 different substances including acyclic compounds (methyl myristate, palmitic acid methyl ester, ethyl palmitate, methyl elaidate, methyl stearate, ethyl oleate, etc.) have been identified from the solid mass of the research object. The most abundant fatty acid esters are methyl oleate (6.831 %) and palmitic acid methyl ester (2.902 %). In addition, the triterpenoid compounds (lupeol acetate, cycloartenol acetate, 3β,13β,14β-13, 27-cycloursan-3-ol acetate) which are characteristic of the L. tatarica have been identified. Lupeol acetate is the predominant component which makes up 56.35 % of the whole obtained substances. Elaidic acid which belongs to the fatty acids group, bis(2-ethylhexyl)phthalate which belongs to the aromatic dicarboxylic acid esters and other compounds have also been identified. Among the identified substances, some are found previously from the other species of the genus Lactuca L. but with regards to the L. tatarica to the best of our knowledge the majority of them are firstly being reported in this study. The investigated plant is widespread in the lowlands and coastal areas of Azerbaijani flora. The availability of some pharmacological effective compounds (lupeol acetate, 3β,13β,14β-13, 27-cycloursan-3-ol acetate, olean-12-en-3-yl acetate) makes the research significant in terms of chemical aspect. Therefore, the results of this investigation open up new horizons for future studies in various fields including the pharmaceutical one.

The Potential of Jatropha variegata Fruits as a Natural Contraceptive: Antifertility Activity and Phytochemical Analysis.

Background Jatropha variegata (family, Euphorbiaceae) is native to Yemen, where it is commonly known as the Ebki shrub. The fruits of the plant are traditionally ingested by local women as a natural method of contraception. This study was undertaken to investigate the phytochemical content of the methanol extract of J. variegata fruits and to evaluate its antifertility potential. Methods Isolation of the chemical constituents was performed by chromatographic techniques, and the chemical structures of these compounds were identified by spectroscopy. The antifertility activity of the methanol extract was assessed in two experimental rat models to explore both the anti-implantation and the estrogenic/antiestrogenic activities in females. In these models, the number of successful implants, the size of litter, and body/ovary weights were all recorded. The development of ovarian follicles was also monitored via histological staining. Results Phytochemical work on the fruit extract of J. variegata led to the isolation of two oils (JF1 and JF2) and methyl elaidate. GC-MS analysis of the JF1 oil revealed that the major chemical constituents were fatty acid esters (43.77%), hydrocarbon alkanes (20.65%), and terpenoids (4.65%), while terpenoids (28.8%), fatty acids and their esters, (29.47%), and phytosterol (10.49%) were the major components found in the JF2 oil. The methanol extract of J. variegata fruit exhibited 50% and 93% abortifacient activity at 150 and 300 mg/kg doses, respectively. The extract also showed significant estrogenic activity as evidenced by the increase in rat ovary weight at a dose of 300 mg/kg compared to the control group. Histological analyses further confirmed this estrogenic activity. Conclusions J. variegata fruits possess an antifertility activity that appeared to result from its antiembryo implantation potential and from its estrogenic activity. The bioactive constituents involved in these activities may need to be further explored and exploited in the pursuit of newer contraceptives.

Synthesis of biodiesel from waste cooking oil using heterogeneous catalyst of Na<sub>2</sub>O/γ-Al<sub>2</sub>O<sub>3</sub> assisted by ultrasonic wave

<abstract> <p>The synthesis of biodiesel <italic>via</italic> transesterification needs to be improved by the heterogeneous catalysts. So, the study aimed to determine the best conditions for the synthesis of biodiesel produced through a transesterification reaction using waste cooking oil with a Na<sub>2</sub>O/γ-Al<sub>2</sub>O<sub>3</sub> catalyst assisted by ultrasonic wave. The steps were: catalyst preparation, oil preparation, esterification, trans-esterification reactions using methanol and various Na<sub>2</sub>O/γ-Al<sub>2</sub>O<sub>3</sub> catalysts, and characterization. The results showed that the refined waste cooking oil using FTIR was known that there was still a carbonyl group indicating the presence of triglycerides. Free Fatty Acid content of waste cooking oil after esterification was 0.40%, so that the transesterification reaction could be carried out. The XRD results of the catalyst showed a conformity with the reference and it was determined by the Scherrer formula that the crystal size of the catalyst was 30.59 nm. The best condition for biodiesel synthesis was obtained at a catalyst ratio of 1:1 as much as concentration 3% w/w for 15 minutes of ultrasonication, 65 ℃, and molar ratio of methanol: oil (12:1), for the yield of 83.51%. After identification through GC-MS, it was known that the main components in the transesterified biodiesel from waste cooking oil were methyl elaidate (38.54%), methyl palmitate (30.90%) and methyl linoleate (16.61%).</p> </abstract>

Transesterification of used frying oil by activated banana peels waste catalyst for biodiesel production

This study aims to investigate the synthesis of biodiesel from used frying oil (UFO) catalyzed by activated banana peels waste (ABPW) catalyst. Raw banana peels waste (RBPW) was activated by phosphoric acid (H3PO4) via one step carbonization method. The activated catalyst was characterized through scanning electron microscopy (SEM), Brunauer, Emmett and Teller (BET) method and fourier transform infrared spectroscopy (FTIR) analyses. The performance of the catalyst was evaluated by varying the transesterification reaction parameters such as methanol to oil volume ratio, amount of catalyst dosage, reaction time and reaction temperature towards the percentage of biodiesel yield. SEM analysis showed both RBPW and ABPW have different morphologies where porous structure was observed before RBPW being activated by H3PO4 and non-porous structure was observed after RBPW being activated by H3PO4. Comparing the textural properties for both RBPW and ABPW, the prepared ABPW catalyst has higher surface area (10.33 m2/g) and adsorption average pore diameter (62.81 Å) compare to RBPW with 4.82 m2/g of surface area and 38.79 Å of adsorption average pore diameter. Furthermore, the different in the existence of the functional group for both materials also justified the activation of BPW by H3PO4 by the preparation method. From the catalytic activity results, the highest biodiesel yield of 85 % has been attained during 15:2 of methanol to oil volume ratio, 0.5 g of catalyst dosage, 90 min of reaction time at 90 °C. However, the result from GC–MS analysis shows that only methyl elaidate and methyl palmitate were found in the biodiesel product. Therefore, improvement need to be done towards the catalyst preparation method in term of its calcination process in the future to obtain a high quality of biodiesel with high composition of FAMEs in the product.

Pharmacological and Phytochemical Assessment of Anagallis arvensis L. Leaf Extracts

The present study elucidates anti-inflammatory potential and biochemical activity via 2,2′-diphenyl-1-picrylhydrazyl scavenging potential (DPPH), total antioxidant activity (TAA), ferric reducing antioxidant power (FRAP), ferrous chelating activity (FCA), total phenolic content (TPC), total flavonoid content (TFC) of aqua-methanol (AqM) and aqua-acetone (AqA) extracts of Anagallis arvensis L. leaf along with mineral content (AAS) and quantitative phytochemicals (FT-IR and GC-MS). AqM extract exhibited maximum anti-inflammatory activity (82.90 ± 0.91%), DPPH (65.06 ± 1.87%), TAA (46.85 ± 7.32 μg VCE/mg), FRAP (73.82 ± 1.21 μg TE/mg), TPC (104.17 ± 1.41 μg GAE/mg); while AqA showed maximum FCA (64.77 ± 1.61%) and TFC (19.12 ± 1.24 μg QE/mg). FT-IR spectra of AqM extract ranged from 1020.58 to 3853.42 cm-1. The major six phytochemicals investigated through GC-MS were 9-octadecenoic acid (Z)-methylester; 2-hexadecen-1-ol-3,7,11,15-tetramethyl- [R-[R*,R*-(E)]]; methyl elaidate; 2-methoxy-4-vinylphenol; 9-octadecenamide-(Z)-; and benzoic acid 2-hydroxy-phenylmethyl ester exhibiting antioxidant and anti-inflammatory properties. The present investigation characterizes the pharmacognostic and phytochemical profile of A. arvensis leading towards its futuristic significance in pharmaceutical and nutraceutical industries.

Micropropagation and Screening of Phytocompounds Present among in vitro Raised and Wild Plants of Rauvolfia serpentine

Rauvolfia serpentina, commonly known as Sarpgandha, is a plant well-known for being utilized for several medicinal purposes. Unrestricted collection from natural stands and overexploitation for medicinal and traditional purposes have rendered it endangered, hence there is necessary requirement for the development of cultivation protocols for mass propagation and sustained utilization of the plant. In the present study, in vitro culture of the apical parts of R. serpentina on MS (Murashige and Skoog) medium enriched with NAA resulted in development of callus, whereas multiple shoot regeneration along with callus development was achieved on medium combination MS + NAA + Kn and MS + NAA + BAP. MS + 4µM NAA + 4µM BAP was found to be most optimum media composition for regeneration of shoots and callus. Among different media combinations utilized for in vitro rooting, a maximum of 82.6 % explants developed in vitro roots on ½ MS + 12µM NAA. Gas chromatography-mass spectrometry (GC-MS) analysis of methanolic extract prepared from leaves of wild and micropropagated plants of R. serpentina revealed the presence of 38 and 48 phytocompounds, respectively. 9, 12-Octadecadienoic acid, Methyl linoleate, Methyl stearate, Hexadecanoic acid, methyl ester, Linoleic acid, Ergost-4, 7, and 22-trien-3.alpha.-ol were some of the major compounds found to be present in the leaves of wild plants, and Linoleic acid, methyl ester, Cis-Linoleic Acid Methyl Ester, Methyl elaidate, hexadecanoic acid, and methyl ester were major compounds found to be present in in vitro raised plants. Many of the compounds detected have been known to possess 1 or more biological or pharmacological activities.

Self-Metathesis of Methyl Oleate Using Ru-NHC Complexes: A Kinetic Study

A kinetic study concerning the self-metathesis of methyl oleate and methyl elaidate was performed, using a variety of NHC-ruthenium pre-catalysts, bearing either mesityl groups or di-isopropyl-phenyl groups on the NHC ligand and various trans ligands with respect to the NHC unit. We showed that the system can be satisfactorily described using one initiation constant per pre-catalyst and four propagation constants that, conversely, do not depend on the pre-catalyst. The difference of reactivity with oleate (Z) and elaidate (E) can be fully explained by the propagation parameters; the studied pre-catalysts initiate with the same rate starting from the Z or the E olefin. The ranking of the propagation parameters is driven by the thermodynamic equilibrium. The transformation rates of Z and E isomers is only driven by these propagation constants and nothing differentiates the initiation step.

Sintesis Natrium Zirkonia Sebagai Katalis Reaksi Transesterifikasi Minyak Goreng Bekas

Catalyst is one of factor that affect the results of the transesterification reaction. Catalyst has spesific properties that can only be used in certain reaction. In order to carry out the transesterification reaction a suitable catalyst is needed and has optimal performance. This research aims to synthesize sodium zirconia (Na2O/ZrO2) as a catalyst for transesterification reaction of used cooking oil into biodiesel and the effect of the concentration of NaOH solution on the zirconia catalyst (ZrO2). The sodium zirconia catalyst(Na2O/ZrO2) was synthesized by wet impregnation method by mixing ZrO2 and NaOH solution with variations in concentrations of 2, 4 and 6 M. Transesterification reaction is carried out with catalyst amount of 5%(w/w), with areaction time of 20 minutes, and by microwave heating at 400 watt microwave power. The comparison of oil molar with methanol was 1:15. Na2O/ZrO2 catalysts was characterized by Fourier Transform Infrared(FT-IR) Spectrophotometer, and X-Ray Diffractometer (XRD) and Scanning Electron Microscopy/Energy Dispersive X-ray (SEM/EDX). The resulting biodiesel was characterized by Gas Chromatography-Mass Spectrometry (GC-MS). Using Na2O/ZrO2 2 M catalysts produced the most biodiesel which was 85.5% (w/w). The formed biodiesel contained methyl palmitate (25,11%), methyl linoleate (10,87%), methyl elaidate (57,88%), and methyl stearate (6,14%). The characterization results showed that Na2O/ZrO2 as the transesterification used cooking oil catalyst was successfully synthesized.

Methyl elaidate: A major compound of potential anticancer extract of Moringa oleifera seeds binds with bax and MDM2 (p53 inhibitor) In silico

Background: Apoptosis is an energy-required programmed cell death process that is vital for normal homeostasis. This is because aged, malfunctioning, and genetically deficient cells such as cancer cells are eliminated through this process to avoid any abnormality in the function of the body system. Earlier, we have reported that the Lipophilic hexane fraction of crude ethanolic extract (HF-CEE) of Moringa oleifera seeds inhibited MCF7 breast cancer cell growth. Objectives: The aims of this study are to identify the esters responsible for HF-CEE cytotoxicity and to determine the ability of the compound to trigger Bax and p53 apoptotic proteins. Materials and Methods: Gas chromatography–mass spectrometry (GC-MS) analysis of the HF-CEE was performed. Methyl elaidate, the major compound identified, was molecularly docked with Bax and MDM2 (p53 inhibitor) using AutoDock 4.2. Drug suitability of methyl elaidate was determined by the rule of “5.” Results: Eleven different esters were identified in HF-CEE by GC-MS. Methyl elaidate was the major anticancer agent among the esters. Methyl elaidate bound with Bax and MDM2 at their active sites that can trigger apoptosis in cancer cells. Finally, methyl elaidate has potential drug properties according to the rule of “5.” Conclusion: Methyl elaidate of HF-CEE could be responsible for its anticancer activity and it is a potential apoptotic agent. Abbreviations used: HF-CEE: Hexane fraction of crude ethanolic extract of Moringa oleifera seeds; GC-MS: Gas chromatography mass spectrometry; MDM2: Mouse double minute 2 homolog.

CATALYTIC ACTIVITY OF CALCIUM OXIDE FROM FISHBONE WASTE IN WASTE <br> COOKING OIL TRANSESTERIFICATION PROCESS

Calcium oxide was obtained from waste fish bones that has been carried out systematically by decomposition at various temperatures that 800oC, 900oC and 1000oC for 4 hours. Calcium oxide from the decomposition process was characterized using XRD, FTIR, SEM EDX and SAA. The result of XRD Diffractogram showed that the crystallinity increased as the calcination temperature increased. The absorption bands in the FTIR spectra of calcium oxide from calcined waste fish bones shown at 355 cm-1 region indicated CaO vibration, which was reinforced by the emergence of a peak at 859 cm-1. Based on the analysis using SEM EDX, the calcined waste fish bones typically irregular particles and contained dominant calcium element. The low value of BET surface area and the total of pore volume were consistent with the adsorption measurement with SAA. The calcium oxide was applied for biodiesel synthesis from Waste cooking oil through transesterification reaction. The result of the optimization that the calcium oxide was decomposed from waste fish bones at 900oC. It exhibited best catalytic activity in the transesterification of waste cooking oil providing maximum biodiesel yield of 93% at 4% (w/v) of catalyst loading. The decomposition of biodiesel are determined by GC MS that produced methyl palmitate, methyl linoleate, methyl elaidate, methyl linoleolate, methyl stearate and methyl linolenate.

Quinone/hydroquinone meroterpenoids with antitubercular and cytotoxic activities produced by the sponge-derived fungus Gliomastix sp. ZSDS1-F7

Fifteen compounds, including six quinone/hydroquinone meroterpenoids, purpurogemutantin (1), macrophorin A (2), 4′-oxomacrophorin (3), 7-deacetoxyyanuthone A (4), 2,3-hydro-deacetoxyyanuthone A (5), 22-deacetylyanuthone A (6), anicequol (7), three roquefortine derivatives, roquefortine C (8), (16S)-hydroxyroquefortine C (9), (16R)-hydroxyroquefortine C (10), dihydroresorcylide (11), nectriapyrone (12), together with three fatty acid derivatives, methyl linoleate (13), phospholipase A2 (14), methyl elaidate (15), were isolated from the sponge-derived fungus Gliomastix sp. ZSDS1-F7 isolated from the sponge Phakellia fusca Thiele collected in the Yongxing island of Xisha. Their structures were elucidated mainly by extensive NMR spectroscopic and mass spectrometric analyses. Among these compounds, compounds 1–3 and 5–7 showed significant in vitro cytotoxicities against the K562, MCF-7, Hela, DU145, U937, H1975, SGC-7901, A549, MOLT-4 and HL60 cell lines, with IC50 values ranging from 0.19 to 35.4 μM. And compounds 2–4 exhibited antitubercular activity with IC50 values of 22.1, 2.44 and 17.5 μM, respectively. Furthermore, compound 7 had anti-enterovirus 71 activity with MIC value of 17.8 μM. To the best of our knowledge, this is the first report to product two quinone/hydroquinone meroterpenoids skeletons (linear skeleton and drimane skeleton) from the same fungal strain.

English

Calophyllum inophyllum methyl esters have a low oxidation stability value (5-6 h) caused by high amounts of polyunsaturated fatty acid methyl esters (FAME), especially methyl linoleate. Partial hydrogenation was done to reduce the number of polyunsaturated FAME to transform them into mono-unsaturated. This was performed at 6 bar and 900 rpm with Pd/Al2O3 solid catalyst in a reactor with a capacity of 1 liter. The research purpose was to learn the effects of reaction temperature (80; 100; 120°C) and time (1; 1.5; 2 h) on the FAME composition. The optimum condition of the experiment was obtained at 120°C for 1 h, with 15.47 h as the oxidation stability value, 17.8°C as the cloud point value, and 51.17 as the cetane number. Under this condition, the methyl linoleate content decreased by 59.89% w/w (from 21.869% to 8,770% w/w) and methyl linoleate hydrogenated into methyl elaidate. Meanwhile, the methyl linolenate content decreased by 85,37% w/w (from 0.205% to 0.030% w/w) and methyl linolenate hydrogenated into methyl linolelaidate. These results show that the research met the following standards: a minimum oxidation stability value of 10 h in accordance with the World Wide Fuel Charter (WWFC) 2009, a maximum cloud point value of 18°C and a minimum cetane number 51 in accordance with SNI 7182-2012. The physical properties values of the Calophyllum inophyllum methyl esters were predicted using the empirical equations.

Non-invasive characterization of the adipogenic differentiation of human bone marrow-derived mesenchymal stromal cells by HS-SPME/GC-MS.

A non-invasive method to characterize human mesenchymal stromal cells during adipogenic differentiation was developed for the first time. Seven fatty acid methyl esters (FAMEs), including methyl laurate, methyl myristate, methyl palmitate, methyl linoleate, methyl oleate, methyl elaidate and methyl stearate, were used for characterizing adipogenic differentiation using headspace solid-phase microextraction (HS-SPME) which is a very simple and non-invasive method for the extraction of volatile compounds. Glassware was used for culturing mesenchymal stromal cells rather than the common plasticware to minimize contamination by volatile impurities. The optimal SPME fiber was selected by comparing diverse fibers containing two pure liquid polymers (PDMS and PA) and two porous solids (PDMS/DVB and CAR/PDMS). Using optimized procedures, we discovered that seven FAMEs were only detected in adipogenic differentiated mesenchymal stromal cells and not in the mesenchymal stromal cells before differentiation. These data could support the quality control of clinical mesenchymal stromal cell culture in the pharmaceutical industry in addition to the development of many clinical applications using mesenchymal stromal cells.

Stereochemistry of C18 Monounsaturated Cork Suberin Acids Determined by Spectroscopic Techniques Including 1 H-NMR Multiplet Analysis of Olefinic Protons

Suberin is a biopolyester responsible for the protection of secondary plant tissues, and yet its molecular structure remains unknown. The C18:1 ω-hydroxyacid and the C18:1 α,ω-diacid are major monomers in the suberin structure, but the configuration of the double bond remains to be elucidated. To unequivocally define the configuration of the C18:1 suberin acids. Pure C18:1 ω-hydroxyacid and C18:1 α,ω-diacid, isolated from cork suberin, and two structurally very close C18:1 model compounds of known stereochemistry, methyl oleate and methyl elaidate, were analysed by NMR spectroscopy, Fourier transform infrared (FTIR) and Raman spectroscopy, and GC-MS. The GC-MS analysis showed that both acids were present in cork suberin as only one geometric isomer. The analysis of dimethyloxazoline (DMOX) and picolinyl derivatives proved the double bond position to be at C-9. The FTIR spectra were concordant with a cis-configuration for both suberin acids, but their unambiguous stereochemical assignment came from the NMR analysis: (i) the chemical shifts of the allylic (13) C carbons were shielded comparatively to the trans model compound, and (ii) the complex multiplets of the olefinic protons could be simulated only with (3) JHH and long-range (4) JHH coupling constants typical of a cis geometry. The two C18:1 suberin acids in cork are (Z)-18-hydroxyoctadec-9-enoic acid and (Z)-octadec-9-enedoic acid.

A comprehensive evaluation of the cetane numbers of fatty acid methyl esters

The cetane number (CN), being related to ignition and combustion behavior, is a prime indicator of the quality of diesel fuels, including those derived from renewable resources such as biodiesel. While many effects of compound structure are known or have been postulated, experimental data have not always been available for the various ester components of biodiesel and a comprehensive evaluation including some structural features not yet experimentally investigated such as double bond configuration and position is lacking. In this work, existing CN data of fatty esters are complemented by studying C18 esters with differing double bond positions and double bond configurations. For the first time, CNs, determined as derived cetane number (DCNs), of neat trans fatty acid methyl esters, methyl elaidate (methyl 9(E)-octadecenoate) and methyl linolelaidate (methyl 9(E),12(E)-octadecenoate), were determined as were the CNs of the C18:1 positional isomers methyl petroselinate (methyl 6(Z)-octadecenoate) and methyl asclepate (methyl 11(Z)-octadecenoate). The CNs of the positional and geometric isomers of methyl oleate are close to the CN of methyl oleate. These data are compared to other previously determined CN data. Furthermore, the applicability of CN data is evaluated using an extensive collection of CN determinations for methyl oleate as “standard” fatty acid (methyl) ester. The average CN value for methyl oleate is in the range of 56–58 with a CN of 57 suggested for calculating purposes. Similarly, uncertainty ranges could be established for CNs of other fatty materials. The data are also useful for predicting CNs of compounds for which CNs are not readily available or easily determinable.

Thiol–ene coupling of 1,2-disubstituted alkene monomers: The kinetic effect of cis/ trans-isomer structures

The free-radical induced reaction between a tri-functional thiol (2-ethyl-(hydroxymethyl)-1,3-propanediol trimercapto propionate) and two 1,2-disubstituted alkenes (methyl oleate and methyl elaidate) has been investigated under photochemical conditions. The photoreaction was monitored via time-resolved FTIR, Raman and NMR spectroscopy to provide insights about the kinetics and efficiency in end-product formation. The information collected was subjected to numerical modelling using the GEPASI software using pre-established literature values for the rate coefficients in order to verify the proposed reaction scheme. The results confirm the thiol–ene reaction mechanism showing a very fast cis/ trans-isomerization (<1.0 min) when compared with the total disappearance of unsaturations, indicating that the rate-limiting step controlling the reaction is the hydrogen transfer from the thiol involved in the formation of product. High thiol–ene conversions can be obtained at reasonable rates without major influence of side-reactions when performed in bulk indicating that this reaction is suitable for network forming purposes with monounsaturated fatty acid methyl esters derivatives. The kinetic and mechanistic information collected provides a basis for the design of new thiol–ene systems aiming at material and coating applications.