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Steven F Vaughn - One of the best experts on this subject based on the ideXlab platform.
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Mustard sinapis alba seed meal suppresses weeds in container grown ornamentals
Hortscience, 2008Co-Authors: Rick A Boydston, Treva Anderson, Steven F VaughnAbstract:Additional index words. containers, natural products, weed control Abstract. Mustard seed meal is a byproduct of Mustard (Sinapis alba L.) grown for oil production. Developing new uses for Mustard seed meal could increase the profitability of growing Mustard. Seed meal of Mustard, var. 'IdaGold', was applied to the soil surface to evaluate its effect on several common weeds in container-grown ornamentals. Mustard seed meal applied to the soil surface of containers at 113, 225, and 450 gm -2 reduced the number of annual bluegrass (Poa annua L.) seedlings by 60%, 86%, and 98%, respectively, and the number of common chickweed (Stellaria media L.) seedlings by 61%, 74%, and 73%, respectively, at 8 weeks after treatment (WAT). Mustard seed meal applied to the soil surface after transplanting Rosa L. hybrid, var. 'Red Sunblaze', Phlox paniculata L., var. 'Franz Schubert', and Coreopsis auriculata L., var. 'Nana' did not injure or affect the flowering or growth of ornamentals. In separate experiments, Mustard seed meal applied at 225 gm -2 to the soil surface reduced the number of emerged seedlings and fresh weight of creeping woodsorrel (Oxalis cornicu- lata) 90% and 95%, respectively, at 8 WAT. Mustard seed meal applied at 450 gm -2 completely prevented woodsorrel emergence at 8 WAT. Mustard seed meal applied postemergence to established liverwort (Marchantia polymorpha L.) at 113, 225, and 450 gm -2 did not injure container-grown Pulsatilla vulgaris Mill., var. 'Heiler Hybrids Mixed' up to 6 WAT and controlled liverwort from 83% to 97% at 6 WAT. Weed suppression with Mustard seed meal generally increased as rate increased from 113 to 450 gm -2 . Mustard seed meal may be useful for selective suppression of annual weeds when applied to the soil surface of container-grown transplanted ornamentals.
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Variation in Allyl Isothiocyanate Production Within Brassica Species and Correlation with Fungicidal Activity
Journal of Chemical Ecology, 1999Co-Authors: Claudia Olivier, Steven F Vaughn, Eduardo S. G. Mizubuti, Rosemary LoriaAbstract:Brassica nigra (black Mustard) and B. juncea (Indian Mustard) genotypes were tested for pathogen suppression and release of allyl isothiocyanate (AITC), a fungitoxic volatile produced in Mustard tissue after enzymatic hydrolysis of allyl glucosinolate (sinigrin). In bioassays, 28 genotypes of B. nigra and 35 genotypes of B. juncea were screened for inhibition of the potato pathogens Helminthosporium solani and Verticillium dahliae by volatiles released from macerated leaf tissue. Release of AITC from plant tissue was quantified by gas chromatography; isothiocyanate profiles were determined by headspace analysis. All Mustard genotypes produced compounds that suppressed radial growth of both fungi. Growth suppression and AITC release differed significantly ( P < 0.001) among genotypes of B. nigra and B. juncea. Mustard treatments releasing >1.2 mg AITC/g plant tissue were fungicidal to both pathogens. Headspace analysis confirmed that allyl glucosinolate was the major glucosinolate in all genotypes of B. nigra tested; most genotypes also produced 2-phenylethyl-isothiocyanate (ITC). Brassica juncea genotypes produced variable amounts of AITC and other volatiles with antimicrobial activity, including 2-phenylethyl-ITC, benzyl-ITC, and 3-butenyl-ITC. Evaluating Mustards from geographically diverse locations allowed selection of Mustard genotypes that may be useful in breeding programs designed to develop disease-suppressing green manure cultivars.
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variation in allyl isothiocyanate production within brassica species and correlation with fungicidal activity
Journal of Chemical Ecology, 1999Co-Authors: Claudia Olivier, Steven F Vaughn, Eduardo S. G. Mizubuti, Rosemary LoriaAbstract:Brassica nigra (black Mustard) and B. juncea (Indian Mustard) genotypes were tested for pathogen suppression and release of allyl isothiocyanate (AITC), a fungitoxic volatile produced in Mustard tissue after enzymatic hydrolysis of allyl glucosinolate (sinigrin). In bioassays, 28 genotypes of B. nigra and 35 genotypes of B. juncea were screened for inhibition of the potato pathogens Helminthosporium solani and Verticillium dahliae by volatiles released from macerated leaf tissue. Release of AITC from plant tissue was quantified by gas chromatography; isothiocyanate profiles were determined by headspace analysis. All Mustard genotypes produced compounds that suppressed radial growth of both fungi. Growth suppression and AITC release differed significantly (P 1.2 mg AITC/g plant tissue were fungicidal to both pathogens. Headspace analysis confirmed that allyl glucosinolate was the major glucosinolate in all genotypes of B. nigra tested; most genotypes also produced 2-phenylethyl-isothiocyanate (ITC). Brassica juncea genotypes produced variable amounts of AITC and other volatiles with antimicrobial activity, including 2-phenylethyl-ITC, benzyl-ITC, and 3-butenyl-ITC. Evaluating Mustards from geographically diverse locations allowed selection of Mustard genotypes that may be useful in breeding programs designed to develop disease-suppressing green manure cultivars.
William R. Wilson - One of the best experts on this subject based on the ideXlab platform.
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Reduction of Nitroarylmethyl Quaternary Ammonium Prodrugs of Mechlorethamine by Radiation
Radiation Research, 1998Co-Authors: William R. Wilson, Dianne M. Ferry, Moana Tercel, Robert F. Anderson, William A. DennyAbstract:Nitroarylmethyl quaternary ammonium nitrogen Mustards are bioreductive drugs designed to release mechlorethamine, when reduced metabolically, via fragmentation of the initial nitro radical anion to a benzylic-type radical. This proposed mechanism (termed Type I) is analogous to the well-known reductive fragmentation of 2-nitrobenzyl halides. The lead nitroarylmethyl quaternary Mustard SN 25246 (NSC 656581), which contains a 2-nitrobenzyl electron acceptor, was shown previously to release mechlorethamine in hypoxic cell cultures and to be a highly selective hypoxic cytotoxin. In the present work the mechanism of reductive release of mechlorethamine from nitroarylmethyl quaternary prodrugs was investigated by steady-state radiolysis with product analysis by high-performance liquid chromatography. SN 25246 releases mechlorethamine in high yield upon reduction, but several reducing equivalents are required (Type II mechanisms). Investigation of other nitroarylmethyl units identified two heterocyclic analogues...
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hypoxia selective antitumor agents 16 nitroarylmethyl quaternary salts as bioreductive prodrugs of the alkylating agent mechlorethamine
Journal of Medicinal Chemistry, 1996Co-Authors: Moana Tercel, William A. Denny, Robert F. Anderson, Alison Hogg, Bronwyn G Siim, William R. WilsonAbstract:Nitrobenzyl quaternary salts of nitrogen Mustards have been previously reported as hypoxia-selective cytotoxins. In this paper we describe the synthesis and evaluation of a series of heterocyclic analogues, including pyrrole, imidazole, thiophene, and pyrazole examples, chosen to cover a range of one-electron reduction potentials (from −277 to −511 mV) and substitution patterns. All quaternary salt compounds were less toxic in vitro than mechlorethamine, and all were more toxic under hypoxic than aerobic conditions, although the differentials were highly variable within the series. The most promising analogue, imidazole 2, demonstrated DNA cross-linking selectively in hypoxic RIF-1 cells, and was active in vivo in combination with radiation or cisplatin. However, 2 also produced unpredictable toxicity in vivo, suggestive of nonspecific nitrogen Mustard release, and this has restricted further development of these compounds as hypoxia-selective cytotoxins.
Rosemary Loria - One of the best experts on this subject based on the ideXlab platform.
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Variation in Allyl Isothiocyanate Production Within Brassica Species and Correlation with Fungicidal Activity
Journal of Chemical Ecology, 1999Co-Authors: Claudia Olivier, Steven F Vaughn, Eduardo S. G. Mizubuti, Rosemary LoriaAbstract:Brassica nigra (black Mustard) and B. juncea (Indian Mustard) genotypes were tested for pathogen suppression and release of allyl isothiocyanate (AITC), a fungitoxic volatile produced in Mustard tissue after enzymatic hydrolysis of allyl glucosinolate (sinigrin). In bioassays, 28 genotypes of B. nigra and 35 genotypes of B. juncea were screened for inhibition of the potato pathogens Helminthosporium solani and Verticillium dahliae by volatiles released from macerated leaf tissue. Release of AITC from plant tissue was quantified by gas chromatography; isothiocyanate profiles were determined by headspace analysis. All Mustard genotypes produced compounds that suppressed radial growth of both fungi. Growth suppression and AITC release differed significantly ( P < 0.001) among genotypes of B. nigra and B. juncea. Mustard treatments releasing >1.2 mg AITC/g plant tissue were fungicidal to both pathogens. Headspace analysis confirmed that allyl glucosinolate was the major glucosinolate in all genotypes of B. nigra tested; most genotypes also produced 2-phenylethyl-isothiocyanate (ITC). Brassica juncea genotypes produced variable amounts of AITC and other volatiles with antimicrobial activity, including 2-phenylethyl-ITC, benzyl-ITC, and 3-butenyl-ITC. Evaluating Mustards from geographically diverse locations allowed selection of Mustard genotypes that may be useful in breeding programs designed to develop disease-suppressing green manure cultivars.
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variation in allyl isothiocyanate production within brassica species and correlation with fungicidal activity
Journal of Chemical Ecology, 1999Co-Authors: Claudia Olivier, Steven F Vaughn, Eduardo S. G. Mizubuti, Rosemary LoriaAbstract:Brassica nigra (black Mustard) and B. juncea (Indian Mustard) genotypes were tested for pathogen suppression and release of allyl isothiocyanate (AITC), a fungitoxic volatile produced in Mustard tissue after enzymatic hydrolysis of allyl glucosinolate (sinigrin). In bioassays, 28 genotypes of B. nigra and 35 genotypes of B. juncea were screened for inhibition of the potato pathogens Helminthosporium solani and Verticillium dahliae by volatiles released from macerated leaf tissue. Release of AITC from plant tissue was quantified by gas chromatography; isothiocyanate profiles were determined by headspace analysis. All Mustard genotypes produced compounds that suppressed radial growth of both fungi. Growth suppression and AITC release differed significantly (P 1.2 mg AITC/g plant tissue were fungicidal to both pathogens. Headspace analysis confirmed that allyl glucosinolate was the major glucosinolate in all genotypes of B. nigra tested; most genotypes also produced 2-phenylethyl-isothiocyanate (ITC). Brassica juncea genotypes produced variable amounts of AITC and other volatiles with antimicrobial activity, including 2-phenylethyl-ITC, benzyl-ITC, and 3-butenyl-ITC. Evaluating Mustards from geographically diverse locations allowed selection of Mustard genotypes that may be useful in breeding programs designed to develop disease-suppressing green manure cultivars.
William A. Denny - One of the best experts on this subject based on the ideXlab platform.
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Reduction of Nitroarylmethyl Quaternary Ammonium Prodrugs of Mechlorethamine by Radiation
Radiation Research, 1998Co-Authors: William R. Wilson, Dianne M. Ferry, Moana Tercel, Robert F. Anderson, William A. DennyAbstract:Nitroarylmethyl quaternary ammonium nitrogen Mustards are bioreductive drugs designed to release mechlorethamine, when reduced metabolically, via fragmentation of the initial nitro radical anion to a benzylic-type radical. This proposed mechanism (termed Type I) is analogous to the well-known reductive fragmentation of 2-nitrobenzyl halides. The lead nitroarylmethyl quaternary Mustard SN 25246 (NSC 656581), which contains a 2-nitrobenzyl electron acceptor, was shown previously to release mechlorethamine in hypoxic cell cultures and to be a highly selective hypoxic cytotoxin. In the present work the mechanism of reductive release of mechlorethamine from nitroarylmethyl quaternary prodrugs was investigated by steady-state radiolysis with product analysis by high-performance liquid chromatography. SN 25246 releases mechlorethamine in high yield upon reduction, but several reducing equivalents are required (Type II mechanisms). Investigation of other nitroarylmethyl units identified two heterocyclic analogues...
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Mono- and dysfunctional nitrogen Mustard analogues of the DNA minor groove binder pibenzimol. Synthesis, cytotoxicity and interaction with DNA.
Anti-cancer drug design, 1998Co-Authors: William A. DennyAbstract:Two series of mono- and dysfunctional aniline Mustards linked to a bisbenzimidazole minor groove binder have been prepared using a new method (polyphosphate ester-mediated direct coupling of appropriate Mustard acids with a preformed advanced phenylenediamine intermediate). As the linker chain attaching the Mustard was lengthened the binding site size of the compounds to calf thymus DNA remained essentially constant at 2.6 nucleotides, but reversible binding strength declined by a factor of 2. Analogues with longer linker chains alkylated DNA much more rapidly than those with shorter chains, consistent with the electronic factors. The short chain analogues also failed to alkylate a 120 bp HindIII to Bg/II fragment of the gpt gene, as measured by gel electrophoresis cleavage assays. The longer chain analogues (both mono- and dysfunctional Mustards) showed patterns of DNA alkylation that varied with chain length. In particular, while most compounds showed substantial N7 alkylation at many guanine residues, the analogue with a (CH2)3 linker chain showed strong alkylation at adenine sites in poly-AT regions. For the longer chain analogues, the bifunctional Mustards were substantially (10- to 20-fold) more cytotoxic than the corresponding monofunctional analogues.
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aniline Mustard analogues of the dna intercalating agent amsacrine dna interaction and biological activity
Anti-cancer Drug Design, 1997Co-Authors: K K Valu, P D Woodgate, Bruce C Baguley, William A. DennyAbstract:Two series of analogues of the clinical antileukemic drug and DNA-intercalating ligand amsacrine have been prepared, containing aniline Mustard sidechains of varying reactivity, linked either at the 4-position of the intercalating acridine chromophore (type A) or at the 1'-position of the 9-anilino group (type B). DNase I footprinting assays showed that compounds of type B had stronger reversible binding to DNA than did compounds of type A. Compounds of each type showed similar patterns of alkylation-induced cleavage of DNA, and alkylate at the N7 of guanines in runs of guanines (similar to the pattern for untargeted Mustards) as well as some adenines. Both classes of compounds crosslinked DNA, although those bearing relatively inactive Mustards did so only at high drug/base pair ratios. However, while the patterns of DNA alkylation were broadly similar, the compounds were considerably more cytotoxic than analogous untargeted Mustards. Comparison of their cytotoxicities in wild-type and DNA repair-deficient lines indicated this toxicity was due to DNA crosslinks (except for the least reactive SO 2 -linked Mustards). The 4-linked analogues showed slightly higher in vivo antileukemic activity than the corresponding 1'-linked analogues.
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hypoxia selective antitumor agents 16 nitroarylmethyl quaternary salts as bioreductive prodrugs of the alkylating agent mechlorethamine
Journal of Medicinal Chemistry, 1996Co-Authors: Moana Tercel, William A. Denny, Robert F. Anderson, Alison Hogg, Bronwyn G Siim, William R. WilsonAbstract:Nitrobenzyl quaternary salts of nitrogen Mustards have been previously reported as hypoxia-selective cytotoxins. In this paper we describe the synthesis and evaluation of a series of heterocyclic analogues, including pyrrole, imidazole, thiophene, and pyrazole examples, chosen to cover a range of one-electron reduction potentials (from −277 to −511 mV) and substitution patterns. All quaternary salt compounds were less toxic in vitro than mechlorethamine, and all were more toxic under hypoxic than aerobic conditions, although the differentials were highly variable within the series. The most promising analogue, imidazole 2, demonstrated DNA cross-linking selectively in hypoxic RIF-1 cells, and was active in vivo in combination with radiation or cisplatin. However, 2 also produced unpredictable toxicity in vivo, suggestive of nonspecific nitrogen Mustard release, and this has restricted further development of these compounds as hypoxia-selective cytotoxins.
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Microbial mutagenic effects of the DNA minor groove binder pibenzimol (Hoechst 33258) and a series of Mustard analogues
Mutation Research Fundamental and Molecular Mechanisms of Mutagenesis, 1995Co-Authors: Lynnette R. Ferguson, William A. DennyAbstract:A series of aniline Mustards and half-Mustards targeted to DNA by linkage (through a polymethylene chain) to the bisbenzimidazole chromophore of pibenzimol (Hoechst 33258) have been evaluated for their mutagenic properties, as estimated in three strains of Salmonella typhimurium, and for their mitotic crossing-over and petite mutagenesis activities in Saccharomyces cerevisiae strain D5. Agarose gel electrophoresis studies showed that only the derivative with the longest linker chain cross-linked DNA, with the remaining compounds being monoalkylators. The parent (non-alkylator) minor groove binding ligand (Hoechst 33258) was inactive in the bacterial strains TA98 or TA100 but weakly mutagenic in TA102, and caused neither mitotic crossing-over nor 'petite' mutagenesis in yeast. Aniline half-Mustard itself (monoalkylator) was an effective base-pair substitution mutagen (events in S. typhimurium strain TA100) with some frameshift mutagenesis activity in TA98, but showed only weak effects in the yeast assays, whereas aniline Mustard (cross-linker) was inactive in these bacterial systems but caused substantial amounts of mitotic crossing-over in yeast. The composite molecules studied here showed effects more characteristic of the minor groove binding chromophore than of alkylating moieties. All showed weak mutagenic activity in TA102 and none in TA98. The only compound to show significant mitotic crossing-over ability was the long-chain derivative which cross-linked DNA. For most of the compounds, the mutagenicity data provided no supportive evidence for DNA alkylation. Since other evidence suggests this does occur readily, it is likely to have a different target to that seen with untargeted aniline Mustards. The significant antitumor activity and low mutagenic potential shown by these compounds make them worthy of further study.
Joseph A. Caruso - One of the best experts on this subject based on the ideXlab platform.
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Screening hydrolysis products of sulfur Mustard agents by high-performance liquid chromatography with inductively coupled plasma mass spectrometry detection
Analytical and Bioanalytical Chemistry, 2009Co-Authors: Karolin K. Kroening, Douglas D. Richardson, Scott Afton, Joseph A. CarusoAbstract:Sulfur Mustard (HD), bis(2-chloroethyl)sulfide, is one of a class of Mustard agents which are chemical warfare agents. The main chemical warfare hydrolysis degradation products of sulfur Mustards are: thiodiglycol, bis(2-hydroxyethylthio)methane, 1,2-bis(2-hydroxyethylthio)ethane, 1,3-bis(2-hydroxyethylthio)propane, and 1,4-bis(2-hydroxyethylthio)butane. The aim of this study is to identify these five hydrolysis degradation products utilizing reversed-phase high-performance liquid chromatography coupled with inductively coupled plasma mass spectrometry (ICP-MS) for element-specific sulfur detection using a collision/reaction cell and electrospray ionization mass spectrometry to confirm the identification. To date, this is the first study utilizing ICP-MS with ^32S element-specific detection for the analysis of vesicant chemical warfare agent degradation products.
