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Tom J. Mabry

Bio: Tom J. Mabry is an academic researcher from University of Texas at Austin. The author has contributed to research in topics: Kaempferol & Sesquiterpene lactone. The author has an hindex of 42, co-authored 459 publications receiving 13375 citations. Previous affiliations of Tom J. Mabry include University of Illinois at Urbana–Champaign & Minia University.


Papers
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Journal ArticleDOI
TL;DR: The sesquiterpene lactone, glaucolide-A, was found to reduce larval feeding when incorporated in a Vernonia powder-agar medium, and the amount of insect feeding was inversely proportional to the concentration of glau COLIDE-A in the medium.

85 citations

Journal ArticleDOI
TL;DR: The hypothesis that the neurotoxicity of BMAA is due to an excitotoxic mechanism, involving elevated intracellular calcium levels and bicarbonate is supported, and the theory that some forms of other neurodiseases may also involve environmental toxins is supported.

85 citations

Journal ArticleDOI
H. Yoshioka1, W. Renold1, N.H. Fischer1, Akio Higo1, Tom J. Mabry1 
TL;DR: In this paper, the isolation and chemistry of four eudesmanolides, reynosin (III), santamarine (IV), α-epoxysantamarine(V), and isotelekin (VII) from Ambrosia confertiflora collected in Mexico were described.

84 citations

Journal ArticleDOI
TL;DR: The comprehensive quantitative analysis of the flavonoid chemistry of Artemisia vulgaris L., a plant used as an emmenagogue in traditional medicine, is presented in conjunction with an evaluation of its estrogenic activity.
Abstract: The comprehensive quantitative analysis of the flavonoid chemistry of Artemisia vulgaris L., a plant used as an emmenagogue in traditional medicine, is presented in conjunction with an evaluation of its estrogenic activity. Twenty known flavonoids were isolated and identified as tricine, jaceosidine, eupafolin, chrysoeriol, diosmetin, homoeriodictyol, isorhamnetin, apigenin, eriodictyol, luteolin, luteolin 7-glucoside, kaempferol 3-glucoside, kaempferol 7-glucoside, kaempferol 3-rhamnoside, kaempferol 3-rutinoside, quercetin 3-glucoside, quercetin 3-galactoside, quercetrin, rutin, and vitexin. The most abundant compounds were eriodictyol and luteolin. The estrogenic activity of all flavonoids was assayed by employing a reconstituted estrogen transcription unit in Saccharomyces cerevisiae transformed with both a human estrogen receptor expression plasmid and a reporter plasmid. Two flavonoids, eriodictyol and apigenin, were able to induce the transcription of the reporter gene in transgenic yeast. The transcriptional activity increased proportionally with increased amounts of purified eriodictyol or apigenin added to the yeast cells.

80 citations

Journal ArticleDOI
TL;DR: It is demonstrated that PAP inactivates pokeweed ribosomes (and is therefore potentially toxic to pokeweed cells) and supports the local suicide model for PAP's in vivo antiviral mechanism.
Abstract: Pokeweed antiviral protein (PAP) and other ribosome-inactivating proteins (RIPs) had previously been thought to be incapable of attacking conspecific ribosomes, thus having no effect on endogenous processes. This assertion conflicts with a model for PAP's in vivo antiviral mechanism in which PAP (a cell wall protein) selectively enters virus-infected cells and disrupts protein synthesis, thus causing local suicide and preventing virus replication. We show here that pokeweed (Phytolacca americana) ribosomes, as well as endod (Phytolacca dodecandra) ribosomes, are indeed highly sensitive to inactivation by conspecific RIPs. Ribosomes isolated from RIP-free pokeweed and endod suspension culture cells were found to be highly active in vitro, as measured by poly(U)-directed polyphenylalanine synthesis. Phytolacca ribosomes challenged with conspecific RIPs generated dose-response curves (IC50 of 1 nM PAP or dodecandrin) very similar to those from wheat germ ribosomes. To determine if Phytolacca cells produce a cytosolic 'anti-RIP' protective element, ribosomes were combined with Phytolacca postribosomal supernatant factors from culture cells, then challenged with conspecific RIPs. Resulting IC50 values of 3-7 nM PAP, PAP-II, PAP-S or dodecandrin indicate that supernatants from these Phytolacca cells lack a ribosomal protective element. This research demonstrates that PAP inactivates pokeweed ribosomes (and is therefore potentially toxic to pokeweed cells) and supports the local suicide model for PAP's in vivo antiviral mechanism. The importance of spatial separation between PAP and ribosomes of cells producing this RIP is emphasized, particularly if crop plants are transformed with the PAP gene to confer antiviral protection.

79 citations


Cited by
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TL;DR: The factors underlying the influence of the different classes of polyphenols in enhancing their resistance to oxidation are discussed and support the contention that the partition coefficients of the flavonoids as well as their rates of reaction with the relevant radicals define the antioxidant activities in the lipophilic phase.

8,513 citations

Journal ArticleDOI
TL;DR: A revised and updated classification for the families of the flowering plants is provided in this paper, which includes Austrobaileyales, Canellales, Gunnerales, Crossosomatales and Celastrales.

7,299 citations

Journal Article
TL;DR: Western medicine has not yet used flavonoids therapeutically, even though their safety record is exceptional, and suggestions are made where such possibilities may be worth pursuing.
Abstract: Flavonoids are nearly ubiquitous in plants and are recognized as the pigments responsible for the colors of leaves, especially in autumn. They are rich in seeds, citrus fruits, olive oil, tea, and red wine. They are low molecular weight compounds composed of a three-ring structure with various substitutions. This basic structure is shared by tocopherols (vitamin E). Flavonoids can be subdivided according to the presence of an oxy group at position 4, a double bond between carbon atoms 2 and 3, or a hydroxyl group in position 3 of the C (middle) ring. These characteristics appear to also be required for best activity, especially antioxidant and antiproliferative, in the systems studied. The particular hydroxylation pattern of the B ring of the flavonoles increases their activities, especially in inhibition of mast cell secretion. Certain plants and spices containing flavonoids have been used for thousands of years in traditional Eastern medicine. In spite of the voluminous literature available, however, Western medicine has not yet used flavonoids therapeutically, even though their safety record is exceptional. Suggestions are made where such possibilities may be worth pursuing.

4,663 citations

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TL;DR: In this article, two complementary colorimetric methods, aluminum chloride method and 2,4-dini trophenylhydrazine method, were used to determine the real content of total flavonoids in propolis.

3,899 citations

Journal ArticleDOI
TL;DR: Several high-quality investigations have examined the relationship between flavonoid structure and antibacterial activity and these are in close agreement, and future studies may allow the development of a pharmacologically acceptable antimicrobial agent or class of agents.

3,630 citations