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Kornkanok Ingkaninan - One of the best experts on this subject based on the ideXlab platform.
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on line hplc ms DPPH Assay for the analysis of phenolic antioxidant compounds in fruit wine antidesma thwaitesianum muell
Food Chemistry, 2010Co-Authors: Nitra Nuengchamnong, Kornkanok IngkaninanAbstract:A reversed phase high performance liquid chromatography (RP-HPLC) separation coupled with an electrospray ionisation mass spectrometry detection (ESI-MS) and the 2,2-diphenyl-1-picrylhydrazyl (DPPH) Assay was used for the screening of multiple antioxidant compounds in Antidesma thwaitesianum Muell. fruit wine. The active compounds were identified by comparison with authentic standards and published mass spectra. With the help of the multidimensional information of LC–ESI-MS/MS and DPPH Assay, the compounds with different chemical structures could be determined in one run successfully. The antioxidant compounds were separated and identified as gallic acid, cyanidin-3-sophoroside, monogalloyl glucoside, delphinidin-3-sambubioside, catechin, caffeic acid, and pelargonidin-3-malonyl glucoside. This result shows that an on-line HPLC–MS–DPPH Assay can be a powerful technique for the rapid characterisation of antioxidant compounds in plant extracts.
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On-line HPLC–MS–DPPH Assay for the analysis of phenolic antioxidant compounds in fruit wine: Antidesma thwaitesianum Muell.
Food Chemistry, 2010Co-Authors: Nitra Nuengchamnong, Kornkanok IngkaninanAbstract:A reversed phase high performance liquid chromatography (RP-HPLC) separation coupled with an electrospray ionisation mass spectrometry detection (ESI-MS) and the 2,2-diphenyl-1-picrylhydrazyl (DPPH) Assay was used for the screening of multiple antioxidant compounds in Antidesma thwaitesianum Muell. fruit wine. The active compounds were identified by comparison with authentic standards and published mass spectra. With the help of the multidimensional information of LC–ESI-MS/MS and DPPH Assay, the compounds with different chemical structures could be determined in one run successfully. The antioxidant compounds were separated and identified as gallic acid, cyanidin-3-sophoroside, monogalloyl glucoside, delphinidin-3-sambubioside, catechin, caffeic acid, and pelargonidin-3-malonyl glucoside. This result shows that an on-line HPLC–MS–DPPH Assay can be a powerful technique for the rapid characterisation of antioxidant compounds in plant extracts.
Nitra Nuengchamnong - One of the best experts on this subject based on the ideXlab platform.
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on line hplc ms DPPH Assay for the analysis of phenolic antioxidant compounds in fruit wine antidesma thwaitesianum muell
Food Chemistry, 2010Co-Authors: Nitra Nuengchamnong, Kornkanok IngkaninanAbstract:A reversed phase high performance liquid chromatography (RP-HPLC) separation coupled with an electrospray ionisation mass spectrometry detection (ESI-MS) and the 2,2-diphenyl-1-picrylhydrazyl (DPPH) Assay was used for the screening of multiple antioxidant compounds in Antidesma thwaitesianum Muell. fruit wine. The active compounds were identified by comparison with authentic standards and published mass spectra. With the help of the multidimensional information of LC–ESI-MS/MS and DPPH Assay, the compounds with different chemical structures could be determined in one run successfully. The antioxidant compounds were separated and identified as gallic acid, cyanidin-3-sophoroside, monogalloyl glucoside, delphinidin-3-sambubioside, catechin, caffeic acid, and pelargonidin-3-malonyl glucoside. This result shows that an on-line HPLC–MS–DPPH Assay can be a powerful technique for the rapid characterisation of antioxidant compounds in plant extracts.
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On-line HPLC–MS–DPPH Assay for the analysis of phenolic antioxidant compounds in fruit wine: Antidesma thwaitesianum Muell.
Food Chemistry, 2010Co-Authors: Nitra Nuengchamnong, Kornkanok IngkaninanAbstract:A reversed phase high performance liquid chromatography (RP-HPLC) separation coupled with an electrospray ionisation mass spectrometry detection (ESI-MS) and the 2,2-diphenyl-1-picrylhydrazyl (DPPH) Assay was used for the screening of multiple antioxidant compounds in Antidesma thwaitesianum Muell. fruit wine. The active compounds were identified by comparison with authentic standards and published mass spectra. With the help of the multidimensional information of LC–ESI-MS/MS and DPPH Assay, the compounds with different chemical structures could be determined in one run successfully. The antioxidant compounds were separated and identified as gallic acid, cyanidin-3-sophoroside, monogalloyl glucoside, delphinidin-3-sambubioside, catechin, caffeic acid, and pelargonidin-3-malonyl glucoside. This result shows that an on-line HPLC–MS–DPPH Assay can be a powerful technique for the rapid characterisation of antioxidant compounds in plant extracts.
Régis Gougeon - One of the best experts on this subject based on the ideXlab platform.
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The Antioxidant Potential of White Wines Relies on the Chemistry of Sulfur-Containing Compounds: An Optimized DPPH Assay
Molecules, 2019Co-Authors: Remy Romanet, Jordi Ballester, Christian Coelho, Youzhong Liu, Florian Bahut, Maria Nikolantonaki, Régis GougeonAbstract:The DPPH (2,2-Diphenyl-1-picrylhydrazyl) Assay is an easy and efficient method commonly used to determine the antioxidant capacity of many food matrices and beverages. In contrast with red wines, white wines are poorer in antioxidant polyphenolics, and the more hydrophilic sulfur-containing compounds in them may contribute significantly to their antioxidant capacity. The modification of the classical DPPH method, with a methanol-buffer and the measure of EC20 (quantity of sample needed to decrease the initial DPPH concentration by 20%) has shown that sulfur-containing compounds such as cysteine (0.037 ± 0.003), glutathione (0.054 ± 0.003) or methanethiol (0.104 ± 0.003) appeared to bear antioxidant capacity comparable to well known phenolic compounds, such as catechin (0.035 ± 0.003), caffeic acid (0.057 ± 0.003) and ferulic acid (0.108 ± 0.003), respectively. In the case of white wines, the comparison with REDOX-sensory scores showed that results from this modified DPPH Assay are strongly correlated with sensory attributes (r = 0.73, p < 0.1). These results provide an unprecedented illustration of the important contribution of these sulfur-containing compounds to the radical quenching ability of white wines.
Takayuki Shibamoto - One of the best experts on this subject based on the ideXlab platform.
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Antioxidant/Lipoxygenase Inhibitory Activities and Chemical Compositions of Selected Essential Oils
Journal of agricultural and food chemistry, 2010Co-Authors: Alfreda Wei, Takayuki ShibamotoAbstract:Twenty-five essential oils were tested for antioxidant activities using a conjugated diene Assay, the aldehyde/carboxylic acid Assay, the DPPH free radical scavenging Assay, and the malonaldehyde/gas chromatography (MA/GC) Assay. They were also tested for lipoxygenase inhibitory activities using the lipoxygenase inhibitor-screening Assay. Thyme oil exhibited the greatest antioxidant effect in all Assays (80−100%) except in the DPPH Assay (60%). Clove leaf oil showed activities comparable to those of thyme oil (53−100%). Cinnamon leaf oil showed strong activities in the aldehyde/carboxylic acid Assay (100%) and DPPH Assay (84%), but only moderate activities in the conjugated diene Assay (24%) and MA/GC Assay (48%). Basil oil exhibited a strong effect in the DPPH Assay (86%) and moderate activities in the MA/GC Assay (35%). Bergamot oil exhibited 100% antioxidant activity in the aldehyde/carboxylic acid Assay. Eucalyptus and chamomile oils showed appreciable activities only in the conjugated diene Assay. Bi...
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antioxidant lipoxygenase inhibitory activities and chemical compositions of selected essential oils
Journal of Agricultural and Food Chemistry, 2010Co-Authors: Takayuki ShibamotoAbstract:Twenty-five essential oils were tested for antioxidant activities using a conjugated diene Assay, the aldehyde/carboxylic acid Assay, the DPPH free radical scavenging Assay, and the malonaldehyde/gas chromatography (MA/GC) Assay. They were also tested for lipoxygenase inhibitory activities using the lipoxygenase inhibitor-screening Assay. Thyme oil exhibited the greatest antioxidant effect in all Assays (80−100%) except in the DPPH Assay (60%). Clove leaf oil showed activities comparable to those of thyme oil (53−100%). Cinnamon leaf oil showed strong activities in the aldehyde/carboxylic acid Assay (100%) and DPPH Assay (84%), but only moderate activities in the conjugated diene Assay (24%) and MA/GC Assay (48%). Basil oil exhibited a strong effect in the DPPH Assay (86%) and moderate activities in the MA/GC Assay (35%). Bergamot oil exhibited 100% antioxidant activity in the aldehyde/carboxylic acid Assay. Eucalyptus and chamomile oils showed appreciable activities only in the conjugated diene Assay. Bi...
Ross A Shalliker - One of the best experts on this subject based on the ideXlab platform.
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Antioxidant Screening of Beverages using the Online HPLC–DPPH • Assay Incorporating Active Flow Technology Chromatography Columns
Processing and Impact on Antioxidants in Beverages, 2014Co-Authors: Michelle Camenzuli, Gary R. Dennis, Harald Ritchie, Ross A ShallikerAbstract:The analysis and isolation of antioxidants from complex samples requires a separation step to fractionate the sample, followed by a means to measure the presence of the antioxidants. This can be conveniently achieved using liquid chromatography coupled with an on-line antioxidant Assay. One such on-line antioxidant Assay involves the diphenylpicrylhydrazyl radical (DPPH•), which provides a positive test for phenolic antioxidants through a decolorization of the DPPH• reagent. In this study we review typical applications involving the DPPH• Assay. Then we demonstrate how this Assay can be improved using recent developments of chromatography technology. The study uses coffee, a complex sample containing numerous antioxidants, to show the efficiency of the new technology. Using this new technology the need to employ large-volume mixing coils is no longer a requirement.
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antioxidant screening of beverages using the online hplc DPPH Assay incorporating active flow technology chromatography columns
Processing and Impact on Antioxidants in Beverages, 2014Co-Authors: Michelle Camenzuli, Gary R. Dennis, Harald Ritchie, Ross A ShallikerAbstract:The analysis and isolation of antioxidants from complex samples requires a separation step to fractionate the sample, followed by a means to measure the presence of the antioxidants. This can be conveniently achieved using liquid chromatography coupled with an on-line antioxidant Assay. One such on-line antioxidant Assay involves the diphenylpicrylhydrazyl radical (DPPH•), which provides a positive test for phenolic antioxidants through a decolorization of the DPPH• reagent. In this study we review typical applications involving the DPPH• Assay. Then we demonstrate how this Assay can be improved using recent developments of chromatography technology. The study uses coffee, a complex sample containing numerous antioxidants, to show the efficiency of the new technology. Using this new technology the need to employ large-volume mixing coils is no longer a requirement.
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Parallel segmented flow chromatography columns with multiplexed detection : an illustration using antioxidant screening of natural products
Microchemical Journal, 2013Co-Authors: Michelle Camenzuli, Gary R. Dennis, Harald Ritchie, Ross A ShallikerAbstract:Abstract The combination of high performance liquid chromatography with the diphenylpicrylhydrazyl radical (DPPH˙) Assay, known as the online DPPH˙ Assay, is widely used for the detection of antioxidants in natural products. The key component in the online DPPH˙ Assay is a reaction coil between the chromatography column and the UV detector. This coil is where the antioxidants leaving the column mix and react with DPPH˙ reagent. The degree to which the antioxidants decolorise the DPPH˙ reagent is measured spectrophotometrically. Reaction coils are usually larger than 100 μL, which is incompatible with high efficiency columns, especially for compounds with low retention eluting from short columns. In this study we use the online DPPH˙ Assay with active flow technology chromatography columns, a new column format current in development. This column uses a new type of end fitting which allows the flow from the column to be segmented into multiple portions. Flow segmentation reduces the volumetric flow from the column without increasing the analysis time. The multiple outlet ports on the active flow column enabled detectors to be multiplexed in parallel, rather than in series, providing faster analysis with less dead volume, and greater sensitivity.