This HPLC method is for the quantification of benzyl isothiocyanate (BITC, 1) released by the act... more This HPLC method is for the quantification of benzyl isothiocyanate (BITC, 1) released by the action of the thioglucosidase enzyme on the substrate glucotropaeolin (2), the predominant glucosinolate of maca hypocotyls. Maca, a native Peruvian member of the cabbage family, is a popular herbal product. Details of the HPLC method for BITC, enzymatically produced from maca powder extracts, as well as highlights of BITC's relevance to human health, are provided.
A high-performance liquid chromatographic (HPLC) method to determine four tocopherols ((Y-, /3-, ... more A high-performance liquid chromatographic (HPLC) method to determine four tocopherols ((Y-, /3-, y-, and S-) simultaneously was developed using a pentafluorophenyl reversed-phase column. A mobile phase of 92% aqueous methanol was used. Tocopherols were measured in vegetable oil, soybean oil deodorizer distillate, mixed tocopherol concentrate, and vitamin E pharmaceutical preparations.
Abstmck Ihe organic extract of Moprounecr 0frioaM was found to contain bershacolone (l), which wa... more Abstmck Ihe organic extract of Moprounecr 0frioaM was found to contain bershacolone (l), which was defined by spectral methods as a unique diterpene containing a cyclobutene ring within a novel carbon skeleton.
The tropical red marine alga WavellS R&,, is a rich source of the physiologicallypotent icosanoid... more The tropical red marine alga WavellS R&,, is a rich source of the physiologicallypotent icosanoid 12-(S)-HEPE, previously only reported from animal tissues and cells. Comparison of our data with that for a reported hydroxyicosapentaenoic acid from the related seaweed uencia m leads us to reassign the latter structure to 12-HEPE. Because l2-(S)-HEPE was hypothesized as a likely intermediate in the biosynthesis of hybridalactone, an unusual-marine prostanoid from L. hvbrida, its isolation from this and related seaweeds provides additional support of a lipoxygenase pathway to prostanoids in marine organisms.
Laurencione was isolated from Laurencia spectabilis and its structure determined to be an equilib... more Laurencione was isolated from Laurencia spectabilis and its structure determined to be an equilibrium mixture of (~)-2-hydroxy-2-methyldihydrofuran-3-one and S-hydroxy-2,3-~ntane~one. On silica gel, laurencione dimerized to optically inactive, crystalline Spiro-his-pinnaketal, a previously reported natural product of L. pj~~ut~~~. LNTRODUCTION
AssTucT.-The organic excracc of Mapounea dfiicana yielded koumbalones A 111 and B [2], defined by... more AssTucT.-The organic excracc of Mapounea dfiicana yielded koumbalones A 111 and B [2], defined by spectral methods as new variations on the casbane ring system. The gross structures, relative configurations, and solution conformations were determined by a combination of spectral analyses and molecular modeling. Because koumbalone A spontaneously converts to koumbalone B at room temperature, koumbalone B may be an artifact of isolation.
A high-performance liquid chromatography method for analyzing the phenolic diterpenes present in ... more A high-performance liquid chromatography method for analyzing the phenolic diterpenes present in rosemary (Rosmarinus officinalis L.) and commercial rosemary extracts is reported. Carnosic acid was the major phenolic diterpene present in rosemary leaves, with lesser amounts of 12methoxycarnosic acid and carnosol. Several commercial rosemary extracts also were analyzed by this method, and in addition to these three compounds, other phenolic diterpenes, such as 7-methoxyrosmanol, 7-methoxy-epirosmanol, and rosmanol, were found in some samples. These latter three compounds seem to be artifacts, produced from carnosic acid by oxidation and cyclization. The major phenolic diterpenes were isolated, and their relative antioxidant activities in soybean oil were measured by the Rancimat. The potency of carnosic acid was more than twice that of any other compound. The antioxidant activity of pure carnosic acid was compared to butylated hydroxytoluene (BHT), butylated hydroxyanisole (BHA), and tertiary butylhydroquinone (TBHQ) and was several times greater than BHT and BHA but less than TBHQ. Nuclear magnetic resonance data for several of the compounds that were incompletely characterized in previous literature are reported . JAOCS 73, 507-514 (1996).
-. The mass detection sensitivity is higher than ultraviolet detection but relies heavily on the ... more -. The mass detection sensitivity is higher than ultraviolet detection but relies heavily on the concentration of acetic acid in the HPLC eluent, which consists of acetonitrile-water-acetic acid. The method is also very specific for the analysis of ginkgolic acid with no interferences from the sample matrix.
A gradient elution reversed-phase HPLC separation of ginger extract has been developed, which giv... more A gradient elution reversed-phase HPLC separation of ginger extract has been developed, which gives better separation than previous isocratic separations. HPLC-UV-electrospray MS has been successfully utilized to identify the individual pungent constituents in the chromatogram of ginger extract. Seven compounds were positively identified as the major 1 1 1 pungent constituents of ginger based on their UV spectra, [M1H] , [M1Na] and characteristic sodiated dimer [2M1Na] ions, and comparison to data for the purified standards: [6]-gingerol and [6]-shogaol. The pungent compounds were assigned as [6]-gingerol, [8]-gingerol, [10]-gingerol, [6]-shogaol, [8]-shogaol, [10]-shogaol and [6]-gingediol. Another eight minor compounds were tentatively identified as gingerol analogues.
a Referenced to the CDCl3 solvent. ∆δ measured in Hz at 500 MHz field strength. b Resonances of p... more a Referenced to the CDCl3 solvent. ∆δ measured in Hz at 500 MHz field strength. b Resonances of protons directly attached to esterified center are not subject to analysis. c Resonances not discernible in overlapped multiplets.
High-performance liquid chromatography paired with UV photodiode-array and electrospray mass spec... more High-performance liquid chromatography paired with UV photodiode-array and electrospray mass spectrometry was investigated as a method for the analysis of alkamides in the roots and achenes of the popular herb Echinacea purpurea (L.) Moench. All alkamides showed very abundant peaks in the reconstructed total ion current chromatogram. Nine alkamides were identified in the root of E. purpurea, similar to the fingerprint reported by Bauer and Remiger [Planta Med., 55 (1989) 367]. Several minor alkamides, not identifiable by previously published techniques, have been also tentatively identified. Two major peaks were identified in E. purpurea achenes as undeca-2E,4Z-diene-8, 10-diynoic acid isobutylamide (1) and dodeca-2E,4E,8E,10E /Z tetraenoic acid isobutylamide (8 / 9). The isomer pair, tetraene 8 / 9, was purified as a standard for quantification of alkamide content in E. purpurea achenes and roots, as well as for the achenes of E. angustifolia DC and E. pallida (Nutt.) Nutt.
hsTRAcr.-The Oregon marine chlorophyte Arroripbonia cwlita produces an assortment of oxidized pol... more hsTRAcr.-The Oregon marine chlorophyte Arroripbonia cwlita produces an assortment of oxidized polyunsaturated fatty acids, or oxylipins. The smallest of these was a IO-carbon conjugated t r i e d 1 with antimicrobial properties. Related to 1 were three novel branched-chain conjugated trienals 4, 9, and 9 in which the aldehyde was present as a branch on a 17sarbon fatty acid chain. Additionally, two novel conjugated unbranched trienone octadecanoids 8 and 10 were also isolated and characterized. Finally, a family of related epoxy-alcohols (11,12,15, and 17) was obtained from A. coalita. Structures were determined by spectroscopic methods in combination with formation of various degradation products and derivatives. The absolute stereochemistry of several of these metabolites was determined by application of exciton chirality circular dichroic spectroscopy on benzoate derivatives.
This HPLC method is for the quantification of benzyl isothiocyanate (BITC, 1) released by the act... more This HPLC method is for the quantification of benzyl isothiocyanate (BITC, 1) released by the action of the thioglucosidase enzyme on the substrate glucotropaeolin (2), the predominant glucosinolate of maca hypocotyls. Maca, a native Peruvian member of the cabbage family, is a popular herbal product. Details of the HPLC method for BITC, enzymatically produced from maca powder extracts, as well as highlights of BITC's relevance to human health, are provided.
A high-performance liquid chromatographic (HPLC) method to determine four tocopherols ((Y-, /3-, ... more A high-performance liquid chromatographic (HPLC) method to determine four tocopherols ((Y-, /3-, y-, and S-) simultaneously was developed using a pentafluorophenyl reversed-phase column. A mobile phase of 92% aqueous methanol was used. Tocopherols were measured in vegetable oil, soybean oil deodorizer distillate, mixed tocopherol concentrate, and vitamin E pharmaceutical preparations.
Abstmck Ihe organic extract of Moprounecr 0frioaM was found to contain bershacolone (l), which wa... more Abstmck Ihe organic extract of Moprounecr 0frioaM was found to contain bershacolone (l), which was defined by spectral methods as a unique diterpene containing a cyclobutene ring within a novel carbon skeleton.
The tropical red marine alga WavellS R&,, is a rich source of the physiologicallypotent icosanoid... more The tropical red marine alga WavellS R&,, is a rich source of the physiologicallypotent icosanoid 12-(S)-HEPE, previously only reported from animal tissues and cells. Comparison of our data with that for a reported hydroxyicosapentaenoic acid from the related seaweed uencia m leads us to reassign the latter structure to 12-HEPE. Because l2-(S)-HEPE was hypothesized as a likely intermediate in the biosynthesis of hybridalactone, an unusual-marine prostanoid from L. hvbrida, its isolation from this and related seaweeds provides additional support of a lipoxygenase pathway to prostanoids in marine organisms.
Laurencione was isolated from Laurencia spectabilis and its structure determined to be an equilib... more Laurencione was isolated from Laurencia spectabilis and its structure determined to be an equilibrium mixture of (~)-2-hydroxy-2-methyldihydrofuran-3-one and S-hydroxy-2,3-~ntane~one. On silica gel, laurencione dimerized to optically inactive, crystalline Spiro-his-pinnaketal, a previously reported natural product of L. pj~~ut~~~. LNTRODUCTION
AssTucT.-The organic excracc of Mapounea dfiicana yielded koumbalones A 111 and B [2], defined by... more AssTucT.-The organic excracc of Mapounea dfiicana yielded koumbalones A 111 and B [2], defined by spectral methods as new variations on the casbane ring system. The gross structures, relative configurations, and solution conformations were determined by a combination of spectral analyses and molecular modeling. Because koumbalone A spontaneously converts to koumbalone B at room temperature, koumbalone B may be an artifact of isolation.
A high-performance liquid chromatography method for analyzing the phenolic diterpenes present in ... more A high-performance liquid chromatography method for analyzing the phenolic diterpenes present in rosemary (Rosmarinus officinalis L.) and commercial rosemary extracts is reported. Carnosic acid was the major phenolic diterpene present in rosemary leaves, with lesser amounts of 12methoxycarnosic acid and carnosol. Several commercial rosemary extracts also were analyzed by this method, and in addition to these three compounds, other phenolic diterpenes, such as 7-methoxyrosmanol, 7-methoxy-epirosmanol, and rosmanol, were found in some samples. These latter three compounds seem to be artifacts, produced from carnosic acid by oxidation and cyclization. The major phenolic diterpenes were isolated, and their relative antioxidant activities in soybean oil were measured by the Rancimat. The potency of carnosic acid was more than twice that of any other compound. The antioxidant activity of pure carnosic acid was compared to butylated hydroxytoluene (BHT), butylated hydroxyanisole (BHA), and tertiary butylhydroquinone (TBHQ) and was several times greater than BHT and BHA but less than TBHQ. Nuclear magnetic resonance data for several of the compounds that were incompletely characterized in previous literature are reported . JAOCS 73, 507-514 (1996).
-. The mass detection sensitivity is higher than ultraviolet detection but relies heavily on the ... more -. The mass detection sensitivity is higher than ultraviolet detection but relies heavily on the concentration of acetic acid in the HPLC eluent, which consists of acetonitrile-water-acetic acid. The method is also very specific for the analysis of ginkgolic acid with no interferences from the sample matrix.
A gradient elution reversed-phase HPLC separation of ginger extract has been developed, which giv... more A gradient elution reversed-phase HPLC separation of ginger extract has been developed, which gives better separation than previous isocratic separations. HPLC-UV-electrospray MS has been successfully utilized to identify the individual pungent constituents in the chromatogram of ginger extract. Seven compounds were positively identified as the major 1 1 1 pungent constituents of ginger based on their UV spectra, [M1H] , [M1Na] and characteristic sodiated dimer [2M1Na] ions, and comparison to data for the purified standards: [6]-gingerol and [6]-shogaol. The pungent compounds were assigned as [6]-gingerol, [8]-gingerol, [10]-gingerol, [6]-shogaol, [8]-shogaol, [10]-shogaol and [6]-gingediol. Another eight minor compounds were tentatively identified as gingerol analogues.
a Referenced to the CDCl3 solvent. ∆δ measured in Hz at 500 MHz field strength. b Resonances of p... more a Referenced to the CDCl3 solvent. ∆δ measured in Hz at 500 MHz field strength. b Resonances of protons directly attached to esterified center are not subject to analysis. c Resonances not discernible in overlapped multiplets.
High-performance liquid chromatography paired with UV photodiode-array and electrospray mass spec... more High-performance liquid chromatography paired with UV photodiode-array and electrospray mass spectrometry was investigated as a method for the analysis of alkamides in the roots and achenes of the popular herb Echinacea purpurea (L.) Moench. All alkamides showed very abundant peaks in the reconstructed total ion current chromatogram. Nine alkamides were identified in the root of E. purpurea, similar to the fingerprint reported by Bauer and Remiger [Planta Med., 55 (1989) 367]. Several minor alkamides, not identifiable by previously published techniques, have been also tentatively identified. Two major peaks were identified in E. purpurea achenes as undeca-2E,4Z-diene-8, 10-diynoic acid isobutylamide (1) and dodeca-2E,4E,8E,10E /Z tetraenoic acid isobutylamide (8 / 9). The isomer pair, tetraene 8 / 9, was purified as a standard for quantification of alkamide content in E. purpurea achenes and roots, as well as for the achenes of E. angustifolia DC and E. pallida (Nutt.) Nutt.
hsTRAcr.-The Oregon marine chlorophyte Arroripbonia cwlita produces an assortment of oxidized pol... more hsTRAcr.-The Oregon marine chlorophyte Arroripbonia cwlita produces an assortment of oxidized polyunsaturated fatty acids, or oxylipins. The smallest of these was a IO-carbon conjugated t r i e d 1 with antimicrobial properties. Related to 1 were three novel branched-chain conjugated trienals 4, 9, and 9 in which the aldehyde was present as a branch on a 17sarbon fatty acid chain. Additionally, two novel conjugated unbranched trienone octadecanoids 8 and 10 were also isolated and characterized. Finally, a family of related epoxy-alcohols (11,12,15, and 17) was obtained from A. coalita. Structures were determined by spectroscopic methods in combination with formation of various degradation products and derivatives. The absolute stereochemistry of several of these metabolites was determined by application of exciton chirality circular dichroic spectroscopy on benzoate derivatives.
Uploads
Papers by Cody Beaumont