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Showing papers by "Tom J. Mabry published in 1995"


Journal ArticleDOI
TL;DR: In this paper, cassumunarins A, B, and C were isolated from the rhizomes of Zingiber cassumum and the structures were determined by spectroscopic methods to be complex curcuminoids.
Abstract: New antioxidants, cassumunarins A, B, and C, were isolated from the rhizomes ofZingiber cassumunar, and the structures were determined by spectroscopic methods to be complex curcuminoids. The antixidant efficiency of cassumunarins was determined by inhibitory activity of autoxidation of linoleic acid in a buffer-ethanol system. The anti-inflammatory effect was measured by inhibition of edema formation on mouse ear induced by 12-O-tetradecanoylphorbol-13-acetate. Both types of activities were stronger for the cassumunarins than for the curcumin.

55 citations


Journal ArticleDOI
TL;DR: Water extraction with subsequent picric acid treatment and solvent washing (ethyl acetate and diethyl ether) was employed for the rapid isolation of free amino acids from non-aqueous food samples, and eleven non-protein amino acids were tentatively identified.

28 citations


Journal ArticleDOI
TL;DR: Two Hymenoxys species afforded, in addition to known compounds, three new pseudoguaianoloides, a new sesquiterpene glucoside and a new butyrolactone, the first report of an eudesmane from the genus Hymanoxys.

22 citations


Journal ArticleDOI
TL;DR: Elicited cell cultures of the cactus Cephalocereus senilis produce a group of flavonoids with unsubstituted B-rings, including an aurone which represents a new class of phytoalexin.

22 citations



Journal ArticleDOI
TL;DR: The results indicated an uneven evolution in the chloroplast genome with different rates of cpDNA evolution in at least a few species ofIva, however, the evolutionary clock hypothesis can not be rejected within most of the lineages inIva.
Abstract: Iva s.str. (comprising ten species) was examined by cpDNA restriction site variation to determine phyletic relationships within the group. The results were compared with relationships proposed from other data. A total of 86 restriction site mutations was detected, 47 of which proved phylogenetically informative. A single most parsimonious tree was obtained using both Wagner and Dollo parsimony. The tree revealed three main lineages that are congruent with the three chromosome lineages (base numbers of x = 16, 17, 18). The monophyly of the x = 16 and 18 groups was supported strongly by molecular data, while the monophyly of x = 17 lineage was only supported moderately. Relationships among the three lineages indicate that the sect.Iva is paraphyletic because sect.Linearbractea is nested within it. Both morphological data and the secondary chemical data are in agreement with the proposed cpDNA phylogeny. Because of this agreement, sect.Iva is revised such that,I. axillaris was excluded and positioned within the newly proposed sect.Rhizoma. Patterns and rates of cpDNA evolution were also examined. The results indicated an uneven evolution in the chloroplast genome with different rates of cpDNA evolution in at least a few species ofIva. However, the evolutionary clock hypothesis can not be rejected within most of the lineages inIva.

10 citations


Journal ArticleDOI
TL;DR: Compared to Franseria, Ambrosia is a much more strongly supported group, and the results indicate that Hymenoclea is closer toFranseria than toAmbrosia, but indicate that the two groups are well separated.
Abstract: The relationship ofAmbrosia (ragweed) andFranseria has long been debated. Their treatment as separate genera has been repeatedly challenged. In this study, chloroplast DNA restriction site variation was examined for species from bothAmbrosia andFranseria as well as taxa from the closely related genusHymenoclea. The chloroplast genomes of members of these three genera were examined using 21 restriction endonucleases and the restriction mutations were used to construct phylogenetic trees. Wagner and Dollo parsimony as well as weighted parsimony were employed to compare the different phylogenies. The results support a close relationship betweenAmbrosia andFranseria, but indicate that the two groups are well separated. Compared toFranseria, Ambrosia is a much more strongly supported group, and the results indicate thatHymenoclea is closer toFranseria than toAmbrosia. The cpDNA phylogeny was used as a framework to examine evolutionary trends in morphology and secondary chemistry.

8 citations


Journal ArticleDOI
TL;DR: Two different derivatives of novel nonprotein amino acids in Gymnocladus dioicus seeds are prepared for gas chromatographic and mass spectrometric analysis, enabling confirmation of molecular weight and existence of functional groups containing active protons.
Abstract: Two different derivatives of novel nonprotein amino acids in Gymnocladus dioicus seeds are prepared for gas chromatographic (GC) and mass spectrometric (MS) analysis. The interfering components in a water extract of the seeds are removed by picric acid treatment and multistep washing with organic solvents followed by N(O,S)-isobutyloxycarbonylation combined with solid-phase extraction. The resulting N(O,S)-isobutyloxycarbonyl (isoBOC) amino acids are then converted to either tert-butyldimethylsilyl (TBDMS) or trimethylsilyl (TMS) derivatives, which are analyzed by dual capillary column GC and GC-MS. The characteristic ions in the mass spectra of N(O,S)-isoBOC TBDMS and N(O,S)-isoBOC TMS derivatives enable confirmation of molecular weight and existence of functional groups containing active protons. Temperature programmed retention index sets measured on DB-5 and DB-17 capillary columns (JW Folsom, CA) are useful for distinguishing among structural isomers. gamma-Methylglutamic acid, diastereoisomers of 3-hydroxy-4-methylglutamic acid, cis and trans isomers of 5-hydroxypipecolic acid, and some free protein amino acids are identified in Gymnocladus dioicus seeds.

5 citations


Journal ArticleDOI
TL;DR: Miao et al. as discussed by the authors used chloroplast DNA variation to investigate evolutionary relationships within Iva s. 1., especially within the controversial section Cyclachaena, and found that most members of this section have relatively close interspecific relationships.
Abstract: Cyclachaena, and Iva s. str.), while others recognize only a single genus Iva s. 1. Although chemical, pollen ultrastructure, and other morphological data have challenged the latter concept, relationships among the segregate taxa are still unclear. The current study used cladistic analyses of chloroplast DNA variation to investigate evolutionary relationships within Iva s. 1., especially within the controversial section Cyclachaena. Nuclear rDNA was also utilized to test for hybrid origin of selected taxa. The results support the dismemberment of Iva s. 1. and recognition of Iva s. str., largely because Iva s. 1. is shown to be paraphyletic. Most members of the section Cyclachaena were found to have relatively close interspecific relationships. Nevertheless, cpDNA data strongly support two lineages within Cyclachaena. One lineage, including L xanthifolia, L acerosa, L nevadensis, and I. dealbata, has a close relationship with the genus Euphrosyne. The second lineage includes only one species, L ambrosiaefolia, which is closely related to Dicoria. The origin of L ambrosiaefolia was shown to be monophyletic, not involving hybridization. One of the major systematic problems in the Asteraceae has been generic circumscription (Lane and Turner, 1985). The family has apparently undergone rapid radiation and differentiation over a relatively short period of time (Raven and Axelrod, 1974). The complex variation pattern has made generic delineation difficult, especially in the subtribe Ambrosiinae. The generic concepts have long been argued, especially the circumscription of Iva and related genera (Miao, Turner, and Mabry, in press; Miao et al., in press) Iva was established by Linnaeus in 1753 in his Species Plantarum. At that time, only two species, I. annua and I. frutescens, were recognized. With the increasing number of new species discovered in New World, controversy as to generic limits of Iva arose. Fresenius (1838) established the genus Cyclachaena based upon Iva xanthifolia; Gray (1853), however, placed it in the genus Euphrosyne. Later, Gray (1886) repositioned this in Iva. Instead of splitting Iva into several smaller genera, Gray (1886) and Hoffmann (1890) treated these as sections Euiva, Cyclachaena, and Chorisiva within an expanded Iva. This arrangement widely influenced subsequent taxonomic workers, but the controversy of generic status for various sectional units

5 citations



Journal Article
TL;DR: Lepechinia urbaniana was investigated with respect to abietane diterpenes, and four widespread and two rare compounds were isolated and characterized.
Abstract: Lepechinia urbaniana was investigated with respect to abietane diterpenes. In addition to four widespread diterpenes, two rare compounds were isolated and characterized.


01 Jan 1995
TL;DR: Cl cladistic analyses of chloroplast DNA variation were used to investigate evolutionary relationships within Iva s.
Abstract: Cyclachaena, and Iva s. str.), while others recognize only a single genus Iva s. 1. Although chemical, pollen ultrastructure, and other morphological data have challenged the latter concept, relationships among the segregate taxa are still unclear. The current study used cladistic analyses of chloroplast DNA variation to investigate evolutionary relationships within Iva s. 1., especially within the controversial section Cyclachaena. Nuclear rDNA was also utilized to test for hybrid origin of selected taxa. The results support the dismemberment of Iva s. 1. and recognition of Iva s. str., largely because Iva s. 1. is shown to be paraphyletic. Most members of the section Cyclachaena were found to have relatively close interspecific relationships. Nevertheless, cpDNA data strongly support two lineages within Cyclachaena. One lineage, including L xanthifolia, L acerosa, L nevadensis, and I. dealbata, has a close relationship with the genus Euphrosyne. The second lineage includes only one species, L ambrosiaefolia, which is closely related to Dicoria. The origin of L ambrosiaefolia was shown to be monophyletic, not involving hybridization. One of the major systematic problems in the Asteraceae has been generic circumscription (Lane and Turner, 1985). The family has apparently undergone rapid radiation and differentiation over a relatively short period of time (Raven and Axelrod, 1974). The complex variation pattern has made generic delineation difficult, especially in the subtribe Ambrosiinae. The generic concepts have long been argued, especially the circumscription of Iva and related genera (Miao, Turner, and Mabry, in press; Miao et al., in press) Iva was established by Linnaeus in 1753 in his Species Plantarum. At that time, only two species, I. annua and I. frutescens, were recognized. With the increasing number of new species discovered in New World, controversy as to generic limits of Iva arose. Fresenius (1838) established the genus Cyclachaena based upon Iva xanthifolia; Gray (1853), however, placed it in the genus Euphrosyne. Later, Gray (1886) repositioned this in Iva. Instead of splitting Iva into several smaller genera, Gray (1886) and Hoffmann (1890) treated these as sections Euiva, Cyclachaena, and Chorisiva within an expanded Iva. This arrangement widely influenced subsequent taxonomic workers, but the controversy of generic status for various sectional units

Journal ArticleDOI
TL;DR: Lepechinia urbaniana was investigated with respect to abietane diterpenes in this paper, and two rare compounds were isolated and characterized in addition to four widespread diterbenes.
Abstract: Lepechinia urbaniana was investigated with respect to abietane diterpenes. In addition to four widespread diterpenes, two rare compounds were isolated and characterized.