Quantitation of estolides by Fourier transform infrared spectroscopy

Erhan, Selim M.; Kleiman, R.; Abbott, Thomas P.

doi:10.1007/bf02518108

Cited by 8 publications

(5 citation statements)

References 9 publications

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“…Compared to the EVOO, the carbonyl absorption of the triacylglycerol esters (1745 cm −1 ) was shifted to the frequency of free carboxylic acids (1707 cm −1 ). The shoulder at 1733 cm −1 is diagnostic of the estolide carbonyl 27 , thereby supporting MS and NMR identifications. The disappearance of the characteristic olefinic C=C stretch absorption (3004 cm −1 ) in Mann-S1 proved the almost complete saturation of the double bonds in the aliphatic chains of FAs.…”

Section: Resultssupporting

confidence: 62%

Olive oil from the 79 A.D. Vesuvius eruption stored at the Naples National Archaeological Museum (Italy)

et al. 2020

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Using a range of chromatographic, spectroscopic, and mass spectrometric analytical techniques, we characterized one of the “edible items” found at the Vesuvius archeological sites and guarded at the National Archaeological Museum of Naples (MANN) in Naples, Italy. We authenticated the specimen contained in a glass bottle (Mann-S1 sample) as originally olive oil and mapped the deep evolution throughout its 2000 years of storage. Triacylglycerols were completely hydrolyzed, while the resulting (hydroxy) fatty acids had partly condensed into rarely found estolides. A complex pattern of volatile compounds arose mainly from breakdown of oleic acid. With excellent approximation, radiocarbon dating placed the find at the time of the Plinian Mount Vesuvius eruption in 79 A.D., indicating that Mann-S1 is probably the oldest residue of olive oil in the world found in bulk amount (nearly 0.7 L).

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Section: Resultssupporting

confidence: 62%

Olive oil from the 79 A.D. Vesuvius eruption stored at the Naples National Archaeological Museum (Italy)

et al. 2020

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“…IR spectra were recorded on a Nicolet model 510 with a Fourier transform spectrometer (Madison WI). 1 H and 13 C NMR spectra were obtained in CDCl 3 solutions on a Varian spectrometer, operating at 250 and 300 MHz for 1 H and 62.5 and 75 MHz for 13 C, and the values are expressed in δ scale relative to internal tetramethylsilane. For the 250 MHz spectrometer the following conditions were used: temperature 27°C, acquisition time 6,396 s, pulse 39.37, and spectral width 5123 Hz.…”

Section: Methodsmentioning

confidence: 99%

“…Estolides are a group of FA polyesters resulting from ester bond formation between a hydroxyl or olefinic group of one FA and the terminal carboxyl group of a second FA (1). Estolides are commonly found in trace amounts as tetraglycerides in several oilseed plants such as the Cruciferaceae Heliophilia amplexicaulis or the Brassicaceae Lesquerella and related genera.…”

mentioning

confidence: 99%

Natural estolides produced by Pseudomonas sp. 42A2 grown on oleic acid: Production and characterization

Peláez

Orellana

Marqués

et al. 2003

J Americ Oil Chem Soc

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Estolides are a group of FA polyesters resulting from ester bond formation between a hydroxyl or olefinic group of one FA and the terminal carboxyl group of a second FA. These products are commonly found in trace amounts, forming tetraglycerides in several oil seed plants, and have been produced by acid clay and enzymatic catalysis in vitro. In this study, natural estolides produced by a bacterial culture are presented for the first time. Pseudomonas sp. 42A2 produced (E)-10-hydroxy-8-octadecenoic acid and (E)-7,10-dihydroxy-8-octadecenoic acid when grown on oleic acid. It is suggested that these FA were polymerized in culture by a lipase produced by the bacterial strain, resulting in a mixture of estolides. These compounds amounted to 3.8 g/L after 72 h of incubation. LC-MS analysis indicated that the types of estolides formed were dimers (m/z 560-610), trimers (m/z 845-906), tetramers (m/z 1122-1202), pentamers (m/z 1328-1424), and hexamers (m/z 1554-1788), with a relative abundance of 27.5, 19.4, 15, 9.7, and 11%, respectively. This is the first report in which hexamers were detected in a bacterial culture.

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“…FTIR spectroscopy is an appropriate and sensitive technique to monitor the synthesis of estolides (Erhan et al, 1996). Figures 1a and 1b show the FTIR spectra of estolides obtained from HOSOL and OPOL, respectively, using different acid-catalyzed methods and reaction times.…”

Section: Chemical Characterization Of Acid Oilsmentioning

confidence: 99%

Chemical, thermal and viscous characterization of high-oleic sunflower and olive pomace acid oils and derived estolides

García‐Zapateiro¹,

Franco²,

Valencia³

et al. 2013

Grasas y Aceites

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RESUMEN Caracterización química, térmica y viscosa de oleí-nas ácidas de girasol alto oleico y orujo de oliva y estó-lidos derivadosEste trabajo presenta la caracterización química, térmica y viscosa de estólidos preparados a partir de oleínas ácidas de girasol alto-oleico y de orujo de oliva, utilizando diferentes métodos catalizados por ácidos y diferentes tiempos de reacción. Se obtuvieron estólidos con pesos moleculares promedios en peso entre 1,7 y 3,4 veces más altos que las oleínas de origen. El peso molecular de los estólidos aumenta cuando se utiliza el método catalizado por ácido sulfúrico y un tiempo de reacción de 3-6 h. Los estólidos obtenidos presentan temperaturas de congelación más altas que las oleínas. En general, los valores de viscosidad están relacionados con el peso molecular del estólido. Se encontraron incrementos significativos de viscosidad en comparación con las oleínas. Los valores máximos de viscosidad se obtuvieron para los estólidos preparados con el método catalizado por ácido sulfúrico. En los estólidos derivados de oleína de orujo de oliva se observaron los mayores incrementos de viscosidad durante las 6 primeras horas de reacción, debido al mayor aumento en el peso molecular. Tiempos más largos de reacción dan lugar a resultados desfavorables. La dependencia de la viscosidad con la temperatura de todos los estólidos es más importante que en las oleínas de partida. PALABRAS CLAVE: Análisis térmico -BiolubricantesEstólido -Oleínas ácidas de girasol alto oleico -Oleínas ácidas de orujo de oliva -Subproductos -Viscosidad. SUMMARY Chemical, thermal and viscous characterization of high-oleic sunflower and olive pomace acid oils and derived estolidesThis work deals with the chemical, thermal and viscous characterization of a variety of estolides, prepared from higholeic sunflower and olive pomace acid oils, using different acid-catalyzed synthesis protocols and reaction times. Estolides with weight-average molecular weights between 1.7 and 3.4 times higher than the original acid oils were obtained. The molecular weight of the estolides was higher when using the sulphuric acid-catalyzed method and a reaction time of 3-6 h. Estolides presented higher freezing temperatures than acid oils. In general, viscosity values are related to estolide molecular weight. Significant increments in viscosities were found in comparison with acid oils. Maximum viscosity values were obtained for estolides prepared using the sulphuric acidcatalyzed method. The largest viscosity increments in olive pomace acid oil-derived estolides were observed during the first 6 hours of reaction, due to an increase in the molecular weight; longer reaction times yielded adverse results. The temperature dependence of viscosity for all estolides studied is significantly larger than for the original acid oils. KEY-WORDS:Biolubricants -Byproducts -Estolides -High-oleic sunflower acid oil -Olive pomace acid oilThermal analysis -Viscosity.

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Quantitation of estolides by Fourier transform infrared spectroscopy

Cited by 8 publications

References 9 publications

Olive oil from the 79 A.D. Vesuvius eruption stored at the Naples National Archaeological Museum (Italy)

Olive oil from the 79 A.D. Vesuvius eruption stored at the Naples National Archaeological Museum (Italy)

Natural estolides produced by Pseudomonas sp. 42A2 grown on oleic acid: Production and characterization

Chemical, thermal and viscous characterization of high-oleic sunflower and olive pomace acid oils and derived estolides

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