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Edwin N. Frankel - One of the best experts on this subject based on the ideXlab platform.
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antioxidant activity of Carnosic Acid and methyl carnosate in bulk oils and oil in water emulsions
Journal of Agricultural and Food Chemistry, 1996Co-Authors: Shu Wen Huang, Robert Aeschbach, Edwin N. Frankel, Karin Schwarz, Bruce J GermanAbstract:This study was aimed at evaluating the antioxidant activities of Carnosic Acid and its methyl ester, methyl carnosate, in inhibiting the formation and decomposition of hydroperoxides in bulk and emulsified corn oil triglycerides at 60 °C. In both lipid systems, methyl carnosate was a better antioxidant than Carnosic Acid, and both were more active than α-tocopherol. The difference in antioxidant activity between methyl carnosate and Carnosic Acid was greater in emulsion than in bulk systems. Carnosic Acid was less stable than methyl carnosate and α-tocopherol in bulk corn oil and 1% Tween 20 micelle solution. The partitioning of Carnosic Acid into the water phase may explain its low activity in emulsions. The measurement of antioxidant depletion may not be a valid method to evaluate antioxidant activities because the antioxidant activities of Carnosic Acid and methyl carnosate were not related to their oxidative stability in bulk oil and Tween 20 solution. Keywords: Antioxidants; Carnosic Acid; methyl car...
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effect of different lipid systems on antioxidant activity of rosemary constituents carnosol and Carnosic Acid with and without α tocopherol
Journal of Agricultural and Food Chemistry, 1996Co-Authors: Anu Hopia, Shu Wen Huang, Bruce J German, Karin Schwarz, Edwin N. FrankelAbstract:The effect of oxidizing lipid substrate on the antioxidant activity of carnosol and Carnosic Acid were evaluated in bulk and emulsified systems. In bulk methyl linoleate, Carnosic Acid was a better antioxidant than carnosol on the basis of conjugated diene hydroperoxide formation, and both were more active than α-tocopherol. However, in linoleic Acid carnosol was more active than Carnosic Acid. In bulk corn oil triglycerides, α-tocopherol exhibited the most antioxidant activity followed by Carnosic Acid and carnosol. In all emulsified systems, α-tocopherol consistently exhibited more antioxidant activity than carnosol and Carnosic Acid. In mixtures, carnosol decreased and Carnosic Acid increased the oxidative stability of α-tocopherol in corn oil. During oxidation Carnosic Acid and carnosol are converted to unknown compounds which exhibit antioxidant activity. The type and polarity of the lipid system used as a model substrate significantly affect the antioxidant activity of carnosol and Carnosic Acid. Ke...
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antioxidant activity of a rosemary extract and its constituents Carnosic Acid carnosol and rosmarinic Acid in bulk oil and oil in water emulsion
Journal of Agricultural and Food Chemistry, 1996Co-Authors: Edwin N. Frankel, Robert Aeschbach, Shu Wen Huang, Elizabeth PriorAbstract:This study was aimed at evaluating the antioxidant activity of a commercial rosemary extract and the active constituents carnosol, Carnosic Acid, and rosmarinic Acid, in inhibiting the formation and decomposition of hydroperoxides in tocopherol-stripped corn oil and in the corresponding corn oil-in-water emulsions. In bulk corn oil, the rosemary extract, Carnosic Acid, rosmarinic Acid, and α-tocopherol were significantly more active than carnosol. In contrast, in corn oil-in-water emulsion, the rosemary compounds were less active than in bulk oil, and the rosemary extract, Carnosic Acid, carnosol, and α-tocopherol were more active than rosmarinic Acid. Similar results were obtained in corn oil-in-water phosphate buffer emulsion at pH 5, but α-tocopherol was less active. Carnosol and Carnosic Acid were much more active antioxidants in corn oil-in-water emulsions buffered at pH 4 and 5 than at pH 7. The decreased antioxidant activity of the polar hydrophilic rosemary compounds in the emulsion system may be ...
Shu Wen Huang - One of the best experts on this subject based on the ideXlab platform.
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antioxidant activity of Carnosic Acid and methyl carnosate in bulk oils and oil in water emulsions
Journal of Agricultural and Food Chemistry, 1996Co-Authors: Shu Wen Huang, Robert Aeschbach, Edwin N. Frankel, Karin Schwarz, Bruce J GermanAbstract:This study was aimed at evaluating the antioxidant activities of Carnosic Acid and its methyl ester, methyl carnosate, in inhibiting the formation and decomposition of hydroperoxides in bulk and emulsified corn oil triglycerides at 60 °C. In both lipid systems, methyl carnosate was a better antioxidant than Carnosic Acid, and both were more active than α-tocopherol. The difference in antioxidant activity between methyl carnosate and Carnosic Acid was greater in emulsion than in bulk systems. Carnosic Acid was less stable than methyl carnosate and α-tocopherol in bulk corn oil and 1% Tween 20 micelle solution. The partitioning of Carnosic Acid into the water phase may explain its low activity in emulsions. The measurement of antioxidant depletion may not be a valid method to evaluate antioxidant activities because the antioxidant activities of Carnosic Acid and methyl carnosate were not related to their oxidative stability in bulk oil and Tween 20 solution. Keywords: Antioxidants; Carnosic Acid; methyl car...
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effect of different lipid systems on antioxidant activity of rosemary constituents carnosol and Carnosic Acid with and without α tocopherol
Journal of Agricultural and Food Chemistry, 1996Co-Authors: Anu Hopia, Shu Wen Huang, Bruce J German, Karin Schwarz, Edwin N. FrankelAbstract:The effect of oxidizing lipid substrate on the antioxidant activity of carnosol and Carnosic Acid were evaluated in bulk and emulsified systems. In bulk methyl linoleate, Carnosic Acid was a better antioxidant than carnosol on the basis of conjugated diene hydroperoxide formation, and both were more active than α-tocopherol. However, in linoleic Acid carnosol was more active than Carnosic Acid. In bulk corn oil triglycerides, α-tocopherol exhibited the most antioxidant activity followed by Carnosic Acid and carnosol. In all emulsified systems, α-tocopherol consistently exhibited more antioxidant activity than carnosol and Carnosic Acid. In mixtures, carnosol decreased and Carnosic Acid increased the oxidative stability of α-tocopherol in corn oil. During oxidation Carnosic Acid and carnosol are converted to unknown compounds which exhibit antioxidant activity. The type and polarity of the lipid system used as a model substrate significantly affect the antioxidant activity of carnosol and Carnosic Acid. Ke...
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antioxidant activity of a rosemary extract and its constituents Carnosic Acid carnosol and rosmarinic Acid in bulk oil and oil in water emulsion
Journal of Agricultural and Food Chemistry, 1996Co-Authors: Edwin N. Frankel, Robert Aeschbach, Shu Wen Huang, Elizabeth PriorAbstract:This study was aimed at evaluating the antioxidant activity of a commercial rosemary extract and the active constituents carnosol, Carnosic Acid, and rosmarinic Acid, in inhibiting the formation and decomposition of hydroperoxides in tocopherol-stripped corn oil and in the corresponding corn oil-in-water emulsions. In bulk corn oil, the rosemary extract, Carnosic Acid, rosmarinic Acid, and α-tocopherol were significantly more active than carnosol. In contrast, in corn oil-in-water emulsion, the rosemary compounds were less active than in bulk oil, and the rosemary extract, Carnosic Acid, carnosol, and α-tocopherol were more active than rosmarinic Acid. Similar results were obtained in corn oil-in-water phosphate buffer emulsion at pH 5, but α-tocopherol was less active. Carnosol and Carnosic Acid were much more active antioxidants in corn oil-in-water emulsions buffered at pH 4 and 5 than at pH 7. The decreased antioxidant activity of the polar hydrophilic rosemary compounds in the emulsion system may be ...
Robert Aeschbach - One of the best experts on this subject based on the ideXlab platform.
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antioxidant activity of Carnosic Acid and methyl carnosate in bulk oils and oil in water emulsions
Journal of Agricultural and Food Chemistry, 1996Co-Authors: Shu Wen Huang, Robert Aeschbach, Edwin N. Frankel, Karin Schwarz, Bruce J GermanAbstract:This study was aimed at evaluating the antioxidant activities of Carnosic Acid and its methyl ester, methyl carnosate, in inhibiting the formation and decomposition of hydroperoxides in bulk and emulsified corn oil triglycerides at 60 °C. In both lipid systems, methyl carnosate was a better antioxidant than Carnosic Acid, and both were more active than α-tocopherol. The difference in antioxidant activity between methyl carnosate and Carnosic Acid was greater in emulsion than in bulk systems. Carnosic Acid was less stable than methyl carnosate and α-tocopherol in bulk corn oil and 1% Tween 20 micelle solution. The partitioning of Carnosic Acid into the water phase may explain its low activity in emulsions. The measurement of antioxidant depletion may not be a valid method to evaluate antioxidant activities because the antioxidant activities of Carnosic Acid and methyl carnosate were not related to their oxidative stability in bulk oil and Tween 20 solution. Keywords: Antioxidants; Carnosic Acid; methyl car...
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antioxidant activity of a rosemary extract and its constituents Carnosic Acid carnosol and rosmarinic Acid in bulk oil and oil in water emulsion
Journal of Agricultural and Food Chemistry, 1996Co-Authors: Edwin N. Frankel, Robert Aeschbach, Shu Wen Huang, Elizabeth PriorAbstract:This study was aimed at evaluating the antioxidant activity of a commercial rosemary extract and the active constituents carnosol, Carnosic Acid, and rosmarinic Acid, in inhibiting the formation and decomposition of hydroperoxides in tocopherol-stripped corn oil and in the corresponding corn oil-in-water emulsions. In bulk corn oil, the rosemary extract, Carnosic Acid, rosmarinic Acid, and α-tocopherol were significantly more active than carnosol. In contrast, in corn oil-in-water emulsion, the rosemary compounds were less active than in bulk oil, and the rosemary extract, Carnosic Acid, carnosol, and α-tocopherol were more active than rosmarinic Acid. Similar results were obtained in corn oil-in-water phosphate buffer emulsion at pH 5, but α-tocopherol was less active. Carnosol and Carnosic Acid were much more active antioxidants in corn oil-in-water emulsions buffered at pH 4 and 5 than at pH 7. The decreased antioxidant activity of the polar hydrophilic rosemary compounds in the emulsion system may be ...
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antioxidant and pro oxidant properties of active rosemary constituents carnosol and Carnosic Acid
Xenobiotica, 1992Co-Authors: Okezie I Aruoma, Robert Aeschbach, Barry Halliwell, J LoligersAbstract:1. Carnosol and Carnosic Acid have been suggested to account for over 90% of the antioxidant properties of rosemary extract.2. Purified carnosol and Carnosic Acid are powerful inhibitors of lipid peroxidation in microsomal and liposomal systems, more effective than propyl gallate.3. Carnosol and Carnosic Acid are good scavengers of peroxyl radicals (CCl3O2) generated by pulse radiolysis, with calculated rate constants of 1–3 × 106M-1 S-1 and 2.7 × 107M-1 S-1 respectively.4. Carnosic Acid reacted with HOCl in such a way as to protect the protein α1-antiproteinase against inactivation.5. Both carnosol and Carnosic Acid stimulated DNA damage in the bleomycin assay but they scavenged hydroxyl radicals in the deoxyribose assay. The calculated rate constants for reaction with ·OH in the deoxyribose system for carnosol and Carnosic Acid were 8.7 × 1010M-1 and 5.9 × 1010M-1 S-1 respectively.6. Carnosic Acid appears to scavenge H2O2, but it could also act as a substrate for the peroxidase system.7. Carnosic Acid a...
Elizabeth Prior - One of the best experts on this subject based on the ideXlab platform.
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antioxidant activity of a rosemary extract and its constituents Carnosic Acid carnosol and rosmarinic Acid in bulk oil and oil in water emulsion
Journal of Agricultural and Food Chemistry, 1996Co-Authors: Edwin N. Frankel, Robert Aeschbach, Shu Wen Huang, Elizabeth PriorAbstract:This study was aimed at evaluating the antioxidant activity of a commercial rosemary extract and the active constituents carnosol, Carnosic Acid, and rosmarinic Acid, in inhibiting the formation and decomposition of hydroperoxides in tocopherol-stripped corn oil and in the corresponding corn oil-in-water emulsions. In bulk corn oil, the rosemary extract, Carnosic Acid, rosmarinic Acid, and α-tocopherol were significantly more active than carnosol. In contrast, in corn oil-in-water emulsion, the rosemary compounds were less active than in bulk oil, and the rosemary extract, Carnosic Acid, carnosol, and α-tocopherol were more active than rosmarinic Acid. Similar results were obtained in corn oil-in-water phosphate buffer emulsion at pH 5, but α-tocopherol was less active. Carnosol and Carnosic Acid were much more active antioxidants in corn oil-in-water emulsions buffered at pH 4 and 5 than at pH 7. The decreased antioxidant activity of the polar hydrophilic rosemary compounds in the emulsion system may be ...
Bruce J German - One of the best experts on this subject based on the ideXlab platform.
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antioxidant activity of Carnosic Acid and methyl carnosate in bulk oils and oil in water emulsions
Journal of Agricultural and Food Chemistry, 1996Co-Authors: Shu Wen Huang, Robert Aeschbach, Edwin N. Frankel, Karin Schwarz, Bruce J GermanAbstract:This study was aimed at evaluating the antioxidant activities of Carnosic Acid and its methyl ester, methyl carnosate, in inhibiting the formation and decomposition of hydroperoxides in bulk and emulsified corn oil triglycerides at 60 °C. In both lipid systems, methyl carnosate was a better antioxidant than Carnosic Acid, and both were more active than α-tocopherol. The difference in antioxidant activity between methyl carnosate and Carnosic Acid was greater in emulsion than in bulk systems. Carnosic Acid was less stable than methyl carnosate and α-tocopherol in bulk corn oil and 1% Tween 20 micelle solution. The partitioning of Carnosic Acid into the water phase may explain its low activity in emulsions. The measurement of antioxidant depletion may not be a valid method to evaluate antioxidant activities because the antioxidant activities of Carnosic Acid and methyl carnosate were not related to their oxidative stability in bulk oil and Tween 20 solution. Keywords: Antioxidants; Carnosic Acid; methyl car...
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effect of different lipid systems on antioxidant activity of rosemary constituents carnosol and Carnosic Acid with and without α tocopherol
Journal of Agricultural and Food Chemistry, 1996Co-Authors: Anu Hopia, Shu Wen Huang, Bruce J German, Karin Schwarz, Edwin N. FrankelAbstract:The effect of oxidizing lipid substrate on the antioxidant activity of carnosol and Carnosic Acid were evaluated in bulk and emulsified systems. In bulk methyl linoleate, Carnosic Acid was a better antioxidant than carnosol on the basis of conjugated diene hydroperoxide formation, and both were more active than α-tocopherol. However, in linoleic Acid carnosol was more active than Carnosic Acid. In bulk corn oil triglycerides, α-tocopherol exhibited the most antioxidant activity followed by Carnosic Acid and carnosol. In all emulsified systems, α-tocopherol consistently exhibited more antioxidant activity than carnosol and Carnosic Acid. In mixtures, carnosol decreased and Carnosic Acid increased the oxidative stability of α-tocopherol in corn oil. During oxidation Carnosic Acid and carnosol are converted to unknown compounds which exhibit antioxidant activity. The type and polarity of the lipid system used as a model substrate significantly affect the antioxidant activity of carnosol and Carnosic Acid. Ke...