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Shu Hai Zhao - One of the best experts on this subject based on the ideXlab platform.
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Allium chemistry hplc analysis of thiosulfinates from onion garlic wild garlic ramsoms leek scallion shallot elephant great headed garlic chive and chinese chive uniquely high allyl to methyl ratios in some garlic samples
Journal of Agricultural and Food Chemistry, 1992Co-Authors: Eric Block, Sriram Naganathan, David Putman, Shu Hai ZhaoAbstract:Room temperature vacuum distillates and extracts of onion (Allium cepa), garlic (Allium sativum), wild garlic (Allium ursinum), leek (Allium porrum L.), scallion (Allium fistulosum L.), shallot (Allium ascalonicum auct.), elephant (or great-headed) garlic (Allium ampeloprasum L. var. ampeloprasum auct.), chive (Allium schoenoprasum L.), and Chinese chive (Allium tuberosum L.) were analyzed by HPLC and 1 H NMR using authentic samples of suspected thiosulfonate components to evaluate the methods
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Allium chemistry: GC-MS analysis of thiosulfinates and related compounds from onion, leek, scallion, shallot, chive, and Chinese chive
Journal of Agricultural and Food Chemistry, 1992Co-Authors: Eric Block, David Putman, Shu Hai ZhaoAbstract:Extracts of onion (Allium cepa), leek (Allium porrum L.), scallion (Allium fistulosum L.), shallot (Allium ascalonicum auct.), chive (Allium schoenoprasum L.), and Chinese chive (Allium tuberosum L.) were analyzed by GC-MS using wide-bore capillary columns (0.53 mm id.) with cryogenic (0 "C) on-column injection and initial column temperature conditions, slow column heating rates (2-5 "C/ min), and GC-MS transfer line temperatures of 80-100 "C. Authentic samples of suspected components were used to verify identities and quantitate amounts, employing benzyl alcohol as internal standard. Under these conditions, thiosulfinates MeS(0)SMe (181, PrS(0)SPr (91, MeSS(0)Pr (13), MeS(0)SPr (14), (2)- and (E)-MeS(O)SCH=CHMe (12, 151, (E)-MeSS(O)CH=CHMe (lo), and (2)- and (E)PrS(O)SCH=CHMe (6, 8) and 2,3-dimethyl-5,6-dithiabicyclo[2.l.llhexane 5-oxides (31,30; cis- and trans-zwiebelanes) were all identified in onion, leek, scallion, shallot, and chive while MeS(0)SMe and (E,Z)-MeS(O)SCH=CHMe were identified in Chinese chive. On the other hand, we could not obtain satisfactory peaks for MeCH=CHS(O)SPr isomers or any thiosulfinates containing a 2-propenyl (allyl) group, which are best identified by HPLC. Sensory data are provided on compounds 30 and 31.
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Allium chemistry hplc analysis of thiosulfinates from onion garlic wild garlic ramsoms leek scallion shallot elephant great headed garlic chive and chinese chive uniquely high allyl to methyl ratios in some garlic samples
Journal of Agricultural and Food Chemistry, 1992Co-Authors: Eric Block, Sriram Naganathan, David Putman, Shu Hai ZhaoAbstract:Room temperature vacuum distillates and extracts of onion (Allium cepa), garlic (Allium sativum), wild garlic (Allium ursinum), leek (Allium porrum L.), scallion (Allium fistulosum L.), shallot (Allium ascalonicum auct.), elephant (or great-headed) garlic (Allium ampeloprasum L. var. ampeloprasum auct.), chive (Allium schoenoprasum L.), and Chinese chive (Allium tuberosum L.) were analyzed by HPLC and 1H NMR using authentic samples of suspected thiosulfinate components to evaluate the methods. Of the eight different thiosulfinates separated and identified in each plant extract, several are reported here for the first time. It is concluded that gas chromatography, as typically performed with high injector and column temperatures, presents an erroneous picture of the competition of room temperature extracts from Allium species and that HPLC provides a reliable qualitative and semiquantitative measure of what is actually present. A simple vacuum distillation procedure facilitating qualitative analysis of Allium volatiles is described. A number of significant trends are noted regarding the varying proportions of different thiosulfinates in each Allium species. In particular, some garlic varieties grown in cooler climates show a higher allyl to methyl ratio than garlic grown in warmer climates.
Eric Block - One of the best experts on this subject based on the ideXlab platform.
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applications of direct analysis in real time mass spectrometry dart ms in Allium chemistry z butanethial s oxide and 1 butenyl thiosulfinates and their s e 1 butenylcysteine s oxide precursor from Allium siculum
Journal of Agricultural and Food Chemistry, 2010Co-Authors: Roman Kubec, Jan Schraml, Robert B Cody, John A Dane, Rabi A Musah, Abith Vattekkatte, Eric BlockAbstract:Lachrymatory (Z)-butanethial S-oxide along with several 1-butenyl thiosulfinates was detected by DART mass spectrometry upon cutting Allium siculum, a popular ornamental Allium species used in some cultures as a spice. (Z)-Butanethial S-oxide isolated from the plant was shown to be identical to a synthetic sample. Its likely precursor, (RS,RC,E)-S-(1-butenyl)cysteine S-oxide (homoisoalliin), was isolated from homogenates of A. siculum, and a closely related species Allium tripedale, and fully characterized. Through use of LC-MS, a series of related γ-glutamyl derivatives were tentatively identified in A. siculum and A. tripedale homogenates, including γ-glutamyl-(E)-S-(1-butenyl)cysteine and its S-oxide, γ-glutamyl-S-butylcysteine and its S-oxide, and γ-glutamyl-S-methylcysteine and its S-oxide. Because compounds containing the 1-butenyl group have not been previously identified in genus Allium species, this work extends the range of known Allium sulfur compounds. The general applicability of DART mass sp...
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garlic and other Alliums the lore and the science
2009Co-Authors: Eric BlockAbstract:1. Allium Botany and Cultivation, Ancient and Modern 2. All Things Allium: Alliums in Literature, the Arts and Culture 3. Allium Chemistry 101: Historical Highlights, Fascinating Facts and Unusual Uses for Alliums 4. Chemistry in a Salad Bowl: Allium Chemistry and Biochemistry 5. Alliums in Folk and Complementary Medicine 6. Alliums in the Environment: Allelopathy and Allium-Derived Attractants, Antibiotics, Herbicides, Pesticides and Repellents
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Allium chemistry hplc analysis of thiosulfinates from onion garlic wild garlic ramsoms leek scallion shallot elephant great headed garlic chive and chinese chive uniquely high allyl to methyl ratios in some garlic samples
Journal of Agricultural and Food Chemistry, 1992Co-Authors: Eric Block, Sriram Naganathan, David Putman, Shu Hai ZhaoAbstract:Room temperature vacuum distillates and extracts of onion (Allium cepa), garlic (Allium sativum), wild garlic (Allium ursinum), leek (Allium porrum L.), scallion (Allium fistulosum L.), shallot (Allium ascalonicum auct.), elephant (or great-headed) garlic (Allium ampeloprasum L. var. ampeloprasum auct.), chive (Allium schoenoprasum L.), and Chinese chive (Allium tuberosum L.) were analyzed by HPLC and 1 H NMR using authentic samples of suspected thiosulfonate components to evaluate the methods
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Allium chemistry: GC-MS analysis of thiosulfinates and related compounds from onion, leek, scallion, shallot, chive, and Chinese chive
Journal of Agricultural and Food Chemistry, 1992Co-Authors: Eric Block, David Putman, Shu Hai ZhaoAbstract:Extracts of onion (Allium cepa), leek (Allium porrum L.), scallion (Allium fistulosum L.), shallot (Allium ascalonicum auct.), chive (Allium schoenoprasum L.), and Chinese chive (Allium tuberosum L.) were analyzed by GC-MS using wide-bore capillary columns (0.53 mm id.) with cryogenic (0 "C) on-column injection and initial column temperature conditions, slow column heating rates (2-5 "C/ min), and GC-MS transfer line temperatures of 80-100 "C. Authentic samples of suspected components were used to verify identities and quantitate amounts, employing benzyl alcohol as internal standard. Under these conditions, thiosulfinates MeS(0)SMe (181, PrS(0)SPr (91, MeSS(0)Pr (13), MeS(0)SPr (14), (2)- and (E)-MeS(O)SCH=CHMe (12, 151, (E)-MeSS(O)CH=CHMe (lo), and (2)- and (E)PrS(O)SCH=CHMe (6, 8) and 2,3-dimethyl-5,6-dithiabicyclo[2.l.llhexane 5-oxides (31,30; cis- and trans-zwiebelanes) were all identified in onion, leek, scallion, shallot, and chive while MeS(0)SMe and (E,Z)-MeS(O)SCH=CHMe were identified in Chinese chive. On the other hand, we could not obtain satisfactory peaks for MeCH=CHS(O)SPr isomers or any thiosulfinates containing a 2-propenyl (allyl) group, which are best identified by HPLC. Sensory data are provided on compounds 30 and 31.
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Allium chemistry hplc analysis of thiosulfinates from onion garlic wild garlic ramsoms leek scallion shallot elephant great headed garlic chive and chinese chive uniquely high allyl to methyl ratios in some garlic samples
Journal of Agricultural and Food Chemistry, 1992Co-Authors: Eric Block, Sriram Naganathan, David Putman, Shu Hai ZhaoAbstract:Room temperature vacuum distillates and extracts of onion (Allium cepa), garlic (Allium sativum), wild garlic (Allium ursinum), leek (Allium porrum L.), scallion (Allium fistulosum L.), shallot (Allium ascalonicum auct.), elephant (or great-headed) garlic (Allium ampeloprasum L. var. ampeloprasum auct.), chive (Allium schoenoprasum L.), and Chinese chive (Allium tuberosum L.) were analyzed by HPLC and 1H NMR using authentic samples of suspected thiosulfinate components to evaluate the methods. Of the eight different thiosulfinates separated and identified in each plant extract, several are reported here for the first time. It is concluded that gas chromatography, as typically performed with high injector and column temperatures, presents an erroneous picture of the competition of room temperature extracts from Allium species and that HPLC provides a reliable qualitative and semiquantitative measure of what is actually present. A simple vacuum distillation procedure facilitating qualitative analysis of Allium volatiles is described. A number of significant trends are noted regarding the varying proportions of different thiosulfinates in each Allium species. In particular, some garlic varieties grown in cooler climates show a higher allyl to methyl ratio than garlic grown in warmer climates.
S Zdravkovickorac - One of the best experts on this subject based on the ideXlab platform.
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comparative study on Allium schoenoprasum cultivated plant and Allium schoenoprasum tissue culture organs antioxidant status
Phytotherapy Research, 2011Co-Authors: D Stajner, D Calicdragosavac, đ Malencic, Boris Popović, S ZdravkovickoracAbstract:This study was designed to examine Allium schoenoprasum tissue culture organs antioxidant and scavenging activity and to make a comparison between Allium schoenoprasum cultivated plant and Allium schoenoprasum tissue culture organs antioxidant activity. This study reports the results on the root, stalk and leaf antioxidant enzyme activities (superoxide dismutase, catalase, guaiacol peroxidase and glutathione peroxidase), reduced glutathione quantity, flavonoids and soluble protein contents and quantities of malonyldialdehyde and .OH radical. In Allium schoenoprasum tissue culture organs the total antioxidant capacity was determined by the FRAP method and scavenger activity by the DPPH method. The present results indicated that the crude extract of Allium schoenoprasum tissue culture exhibited antioxidant and scavenging abilities in all investigated plant parts, especially in the roots. According to our results, the tissue culture plants exhibited the highest activities in the roots in contrast to the cultivated plants where highest activities were observed in the leaves. Copyright © 2011 John Wiley & Sons, Ltd.
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comparative study on Allium schoenoprasum cultivated plant and Allium schoenoprasum tissue culture organs antioxidant status
Phytotherapy Research, 2011Co-Authors: D Stajner, D Calicdragosavac, đ Malencic, B M Popovic, S ZdravkovickoracAbstract:This study was designed to examine Allium schoenoprasum tissue culture organs antioxidant and scavenging activity and to make a comparison between Allium schoenoprasum cultivated plant and Allium schoenoprasum tissue culture organs antioxidant activity. This study reports the results on the root, stalk and leaf antioxidant enzyme activities (superoxide dismutase, catalase, guaiacol peroxidase and glutathione peroxidase), reduced glutathione quantity, flavonoids and soluble protein contents and quantities of malonyldialdehyde and ·OH radical. In Allium schoenoprasum tissue culture organs the total antioxidant capacity was determined by the FRAP method and scavenger activity by the DPPH method. The present results indicated that the crude extract of Allium schoenoprasum tissue culture exhibited antioxidant and scavenging abilities in all investigated plant parts, especially in the roots. According to our results, the tissue culture plants exhibited the highest activities in the roots in contrast to the cultivated plants where highest activities were observed in the leaves.
D Stajner - One of the best experts on this subject based on the ideXlab platform.
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comparative study on Allium schoenoprasum cultivated plant and Allium schoenoprasum tissue culture organs antioxidant status
Phytotherapy Research, 2011Co-Authors: D Stajner, D Calicdragosavac, đ Malencic, Boris Popović, S ZdravkovickoracAbstract:This study was designed to examine Allium schoenoprasum tissue culture organs antioxidant and scavenging activity and to make a comparison between Allium schoenoprasum cultivated plant and Allium schoenoprasum tissue culture organs antioxidant activity. This study reports the results on the root, stalk and leaf antioxidant enzyme activities (superoxide dismutase, catalase, guaiacol peroxidase and glutathione peroxidase), reduced glutathione quantity, flavonoids and soluble protein contents and quantities of malonyldialdehyde and .OH radical. In Allium schoenoprasum tissue culture organs the total antioxidant capacity was determined by the FRAP method and scavenger activity by the DPPH method. The present results indicated that the crude extract of Allium schoenoprasum tissue culture exhibited antioxidant and scavenging abilities in all investigated plant parts, especially in the roots. According to our results, the tissue culture plants exhibited the highest activities in the roots in contrast to the cultivated plants where highest activities were observed in the leaves. Copyright © 2011 John Wiley & Sons, Ltd.
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comparative study on Allium schoenoprasum cultivated plant and Allium schoenoprasum tissue culture organs antioxidant status
Phytotherapy Research, 2011Co-Authors: D Stajner, D Calicdragosavac, đ Malencic, B M Popovic, S ZdravkovickoracAbstract:This study was designed to examine Allium schoenoprasum tissue culture organs antioxidant and scavenging activity and to make a comparison between Allium schoenoprasum cultivated plant and Allium schoenoprasum tissue culture organs antioxidant activity. This study reports the results on the root, stalk and leaf antioxidant enzyme activities (superoxide dismutase, catalase, guaiacol peroxidase and glutathione peroxidase), reduced glutathione quantity, flavonoids and soluble protein contents and quantities of malonyldialdehyde and ·OH radical. In Allium schoenoprasum tissue culture organs the total antioxidant capacity was determined by the FRAP method and scavenger activity by the DPPH method. The present results indicated that the crude extract of Allium schoenoprasum tissue culture exhibited antioxidant and scavenging abilities in all investigated plant parts, especially in the roots. According to our results, the tissue culture plants exhibited the highest activities in the roots in contrast to the cultivated plants where highest activities were observed in the leaves.
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exploring Allium species as a source of potential medicinal agents
Phytotherapy Research, 2006Co-Authors: D Stajner, Natasa Milic, Jasna Canadanovicbrunet, Agnes Kapor, M Stajner, B M PopovicAbstract:It has been shown that Allium species may help to prevent tumor promotion, cardiovascular diseases and aging; all processes that are associated with free radicals. Therefore the Allium species of both cultivated species (Allium nutans L., Allium fistulosum L., Allium vineale L., Allium psekemense B. Fedtsch, Allium cepa L., Allium sativum L.) and wild species (Allium flavum L., Allium sphaerocephalum L., Allium atroviolaceum Boiss, Allium schenoprasum L., Allium vineale L., Allium ursinum L., Allium scorodoprasum L.) from various locations were investigated for their antioxidative properties. The leaves were examined for activities of antioxidative enzymes (catalase, peroxidase, superoxide-dismutase, glutathione-peroxidase), non-enzymic antioxidants (reduced glutathione and total flavonoids), content of soluble proteins, vitamin C, carotenoids, chlorophylls a and b, as well as the quantities of malonyldialdehyde and *OH and O2*- radicals. Using a contemporary spectroscopic fluorescent method, lipofuscin, 'plant age pigments' were determined. ESR spectroscopy was used to follow the decrease of oxygen radicals in the presence of extracts of Allium species in phosphate buffer (pH 7). The results showed that all Allium species had strong antioxidative properties due to their high concentration of total flavonoids, high content of carotenoids and chlorophylls, and very low concentrations of toxic oxygen radicals. ESR signals of DMPO-OH radical adducts, in the presence of Allium extracts in phosphate buffer (pH 7), were reduced by up to 94.3%.
David Putman - One of the best experts on this subject based on the ideXlab platform.
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Allium chemistry hplc analysis of thiosulfinates from onion garlic wild garlic ramsoms leek scallion shallot elephant great headed garlic chive and chinese chive uniquely high allyl to methyl ratios in some garlic samples
Journal of Agricultural and Food Chemistry, 1992Co-Authors: Eric Block, Sriram Naganathan, David Putman, Shu Hai ZhaoAbstract:Room temperature vacuum distillates and extracts of onion (Allium cepa), garlic (Allium sativum), wild garlic (Allium ursinum), leek (Allium porrum L.), scallion (Allium fistulosum L.), shallot (Allium ascalonicum auct.), elephant (or great-headed) garlic (Allium ampeloprasum L. var. ampeloprasum auct.), chive (Allium schoenoprasum L.), and Chinese chive (Allium tuberosum L.) were analyzed by HPLC and 1 H NMR using authentic samples of suspected thiosulfonate components to evaluate the methods
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Allium chemistry: GC-MS analysis of thiosulfinates and related compounds from onion, leek, scallion, shallot, chive, and Chinese chive
Journal of Agricultural and Food Chemistry, 1992Co-Authors: Eric Block, David Putman, Shu Hai ZhaoAbstract:Extracts of onion (Allium cepa), leek (Allium porrum L.), scallion (Allium fistulosum L.), shallot (Allium ascalonicum auct.), chive (Allium schoenoprasum L.), and Chinese chive (Allium tuberosum L.) were analyzed by GC-MS using wide-bore capillary columns (0.53 mm id.) with cryogenic (0 "C) on-column injection and initial column temperature conditions, slow column heating rates (2-5 "C/ min), and GC-MS transfer line temperatures of 80-100 "C. Authentic samples of suspected components were used to verify identities and quantitate amounts, employing benzyl alcohol as internal standard. Under these conditions, thiosulfinates MeS(0)SMe (181, PrS(0)SPr (91, MeSS(0)Pr (13), MeS(0)SPr (14), (2)- and (E)-MeS(O)SCH=CHMe (12, 151, (E)-MeSS(O)CH=CHMe (lo), and (2)- and (E)PrS(O)SCH=CHMe (6, 8) and 2,3-dimethyl-5,6-dithiabicyclo[2.l.llhexane 5-oxides (31,30; cis- and trans-zwiebelanes) were all identified in onion, leek, scallion, shallot, and chive while MeS(0)SMe and (E,Z)-MeS(O)SCH=CHMe were identified in Chinese chive. On the other hand, we could not obtain satisfactory peaks for MeCH=CHS(O)SPr isomers or any thiosulfinates containing a 2-propenyl (allyl) group, which are best identified by HPLC. Sensory data are provided on compounds 30 and 31.
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Allium chemistry hplc analysis of thiosulfinates from onion garlic wild garlic ramsoms leek scallion shallot elephant great headed garlic chive and chinese chive uniquely high allyl to methyl ratios in some garlic samples
Journal of Agricultural and Food Chemistry, 1992Co-Authors: Eric Block, Sriram Naganathan, David Putman, Shu Hai ZhaoAbstract:Room temperature vacuum distillates and extracts of onion (Allium cepa), garlic (Allium sativum), wild garlic (Allium ursinum), leek (Allium porrum L.), scallion (Allium fistulosum L.), shallot (Allium ascalonicum auct.), elephant (or great-headed) garlic (Allium ampeloprasum L. var. ampeloprasum auct.), chive (Allium schoenoprasum L.), and Chinese chive (Allium tuberosum L.) were analyzed by HPLC and 1H NMR using authentic samples of suspected thiosulfinate components to evaluate the methods. Of the eight different thiosulfinates separated and identified in each plant extract, several are reported here for the first time. It is concluded that gas chromatography, as typically performed with high injector and column temperatures, presents an erroneous picture of the competition of room temperature extracts from Allium species and that HPLC provides a reliable qualitative and semiquantitative measure of what is actually present. A simple vacuum distillation procedure facilitating qualitative analysis of Allium volatiles is described. A number of significant trends are noted regarding the varying proportions of different thiosulfinates in each Allium species. In particular, some garlic varieties grown in cooler climates show a higher allyl to methyl ratio than garlic grown in warmer climates.