Quantitative NMR spectroscopy of biologically active substances and excipients

Beyer, Tanja; Diehl, Bernd; Holzgrabe, Ulrike

doi:10.1007/978-3-642-36303-0_6

Cited by 6 publications

(7 citation statements)

References 93 publications

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“…The experiment was designed to compare the oxidative stability of TAG molecules in which the positional distribution of L was different (i.e., SO vs. SSO). In agreement with previous literature [27][28][29], a typical 1 H-NMR spectrum obtained from unoxidized SO contains 10 well-known signals; their assignments are shown in Fig. 1A, B.…”

Section: Degradation Of Main Components Of Oil In So and Ssosupporting

confidence: 90%

Effect of Positional Distribution of Linoleic Acid on Oxidative Stability of Triacylglycerol Molecules Determined by ¹H NMR

Wang

Yang

Gan

et al. 2015

J Americ Oil Chem Soc

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1H nuclear magnetic resonance (1H NMR) was used to determine the effect of positional distribution of linoleic acid (L) on the oxidative stability of triacylglycerols. For this purpose, structured soybean oil (SSO), which had a similar total fatty acid composition but a different L positional distribution than soybean oil (SO), was produced by interesterification reaction. The SO and SSO were oxidized in the dark at 40 °C. Afterwards, 1H NMR was used to monitor the oxidation process and quantify the main polyunsaturated fatty acid, Z,E‐ and E,E‐conjugated forms, hydroperoxides, and aldehydes at different oxidation periods in a single run. After 45 days of oxidation, SSO showed lower L content than SO (9.9 ± 1.1 and 16.8 ± 0.5 %, respectively). Additionally, secondary oxidation products in SSO were shown to be more abundant than in SO (82.3 ± 4.9 and 43.6 ± 0.9 mmol/L oil, respectively). This study indicated that SO, which contains a higher distribution of L at the sn‐2 position, was more resistant to autoxidation than SSO.

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Section: Degradation Of Main Components Of Oil In So and Ssosupporting

confidence: 90%

Effect of Positional Distribution of Linoleic Acid on Oxidative Stability of Triacylglycerol Molecules Determined by ¹H NMR

Wang

Yang

Gan

et al. 2015

J Americ Oil Chem Soc

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“…Since the integral of an 1 H-NMR signal is proportional to the number of protons, the molar concentration of the hydroperoxide groups can be determined by 1 H-NMR [21,22]. Recently, Guillen and Goicoechea reported the use of the proton signal of non-deuterated chloroform occurring in deuterated chloroform for the quantification of the oxidation products [23].…”

Section: Introductionmentioning

confidence: 99%

¹H‐NMR Spectroscopy as a New Tool in the Assessment of the Oxidative State in Edible Oils

Skiera

Steliopoulos

Kuballa

et al. 2012

J Americ Oil Chem Soc

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Within the course of lipid peroxidation, hydroperoxides are formed as primary products. They can be used as analytical markers to assess the deterioration status of oils and fats. Here a new 1 H-NMR assay to determine the hydroperoxide amount in edible oils is presented. We were able to show that the analytical performance of the method is similar to that of the commonly used peroxide value (PV) according to Wheeler. A total of 290 edible oil samples were analyzed using both methods. For some oil varieties considerable discrepancies were found between the results obtained. In the case of black seed and olive oil, two substances could be identified that cause positive (black seed oil) and negative (olive oils) deviations from the theoretical PV expected from the NMR values.

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“…Hydroperoxides are the primary products of lipid oxidation, and hence, peroxide content (peroxide value, PV) is often used to detect the initial stage of oxidation (Guillén and Cabo ). Also, conjugated diene level is sometimes exchangeable with PV because many hydroperoxides contain a conjugated diene system (Beyer and others ). In order to confirm the results of PV from 200 ppm CAPE and 4‐VC + α‐tocopherol (100 ppm + 100 ppm), 1 H NMR was used to simultaneously investigate the formation of primary oxidants, such as, ( Z,E ) and ( E,E ) conjugated dienic systems, and secondary oxidation compounds (i.e., aldehydes).…”

Section: Resultsmentioning

confidence: 99%

“…In order to confirm the results of PV from 200 ppm CAPE and 4‐VC + α‐tocopherol (100 ppm + 100 ppm), 1 H NMR was used to simultaneously investigate the formation of primary oxidants, such as, ( Z,E ) and ( E,E ) conjugated dienic systems, and secondary oxidation compounds (i.e., aldehydes). The principle of quantification was that the integrated 1 H NMR signals were proportional to proton numbers (Beyer and others ; Holzgrabe ).…”

Section: Resultsmentioning

confidence: 99%

Antioxidant Properties of Caffeic acid Phenethyl Ester and 4‐Vinylcatechol in Stripped Soybean Oil

Jia

Wang

et al. 2015

Journal of Food Science

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Caffeic acid was used to synthesize 4-vinylcatechol (4-VC) by thermal decarboxylation and to prepare caffeic acid phenethyl ester (CAPE) by esterification reaction. The identities of synthesized products were confirmed by (1)H NMR. Antioxidative activities of 4-VC and CAPE were compared with α-tocopherol and BHT in stripped soybean oil at 60 °C under the dark. To evaluate the degrees of oxidation at different concentrations and combinations, peroxide value (PV) and (1)H NMR were performed. From the results of PV, the formation of primary oxidation products (i.e., hydroperoxides) in stripped soybean oil containing 200 ppm CAPE was the slowest. The relative oxidation degree of 200 ppm CAPE (9.5%) was lower than other samples on 9 d. Similar results were obtained by (1)H NMR analysis. After 15 d of storage, levels of conjugated diene forms and aldehydes of 200 ppm CAPE sample (57.3 and 0.9 mmol/mol oil) were also lower than other treatments. In addition, 4-VC and α-tocopherol were found to have a synergistic antioxidant effect.

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Quantitative NMR spectroscopy of biologically active substances and excipients

Cited by 6 publications

References 93 publications

Effect of Positional Distribution of Linoleic Acid on Oxidative Stability of Triacylglycerol Molecules Determined by ¹H NMR

Effect of Positional Distribution of Linoleic Acid on Oxidative Stability of Triacylglycerol Molecules Determined by ¹H NMR

¹H‐NMR Spectroscopy as a New Tool in the Assessment of the Oxidative State in Edible Oils

Antioxidant Properties of Caffeic acid Phenethyl Ester and 4‐Vinylcatechol in Stripped Soybean Oil

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Quantitative NMR spectroscopy of biologically active substances and excipients

Cited by 6 publications

References 93 publications

Effect of Positional Distribution of Linoleic Acid on Oxidative Stability of Triacylglycerol Molecules Determined by 1H NMR

Effect of Positional Distribution of Linoleic Acid on Oxidative Stability of Triacylglycerol Molecules Determined by 1H NMR

1H‐NMR Spectroscopy as a New Tool in the Assessment of the Oxidative State in Edible Oils

Antioxidant Properties of Caffeic acid Phenethyl Ester and 4‐Vinylcatechol in Stripped Soybean Oil

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Effect of Positional Distribution of Linoleic Acid on Oxidative Stability of Triacylglycerol Molecules Determined by ¹H NMR

Effect of Positional Distribution of Linoleic Acid on Oxidative Stability of Triacylglycerol Molecules Determined by ¹H NMR

¹H‐NMR Spectroscopy as a New Tool in the Assessment of the Oxidative State in Edible Oils