Structure-antioxidant activity relationships of flavonoids and phenolic acids

http://amborella.net/2010PlantSystematics/DATA/3-24-APG%202003%20Bot%20J%20Linn%20Soc%20APGII.pdf

An update of the Angiosperm Phylogeny Group classification for the orders and families of flowering plants: APG II

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.

The Effects of Plant Flavonoids on Mammalian Cells:Implications for Inflammation, Heart Disease, and Cancer

Estimation of total flavonoid content in propolis by two complementary colorimetric methods

Antimicrobial activity of flavonoids

Flavonoids from Brickellia scoparia

Systematic implications of flavonoids in Hazardia

A B S T R A C T Effects of hybridization on sesquiterpene lactones in Xanthium strumarium were studied for clues to the relationship of Old and New World populations. In crosses between indigenous Asiatic plants in the "strumarium" morphological complex and various American complexes that produce xanthinin as a major sesquiterpene lactone, the F1 hybrids contained xanthinin and the related compounds, xanthanol, xanthatin, and xanthinosin. In other crosses with various American complexes that produce xanthumin, the stereoisomer of xanthinin, the F1 hybrids contained xanthinin and xanthumin as well as xarithinin-related compounds and their stereoisomers, xanthumanol, deacetoxylxanthumin, and tomentosin. The Asiatic plants of "strumarium" from Hong Kong involved in the crosses produce approximately equal percentages of xanthinin, xanthatin and xanthinosin, but those from India contain only xanthinosin. The putative introduction of the American morphological complex, "chinense," contains xanthumin as the major component but shows chemical diversity that indicates genes derived from the indigenous "strumarium" complex. SESQUITERPENE LACTONES, the bitter principles of many species in the Compositae, were studied in experimental hybrids of Xanthium strumarium L. (sensu lato) for clues to the relationship of Old and New World populations. Infraspecific variation of sesquiterpene lactones has been reported in Xanthium by Winters, Geissman, and Safir (1969), McMillan (1971, 1972, 1974a) and McMillan et al. (1975) and is a well established phenomenon in other species of Compositae (Mabry, 1970; Geissman and Lee, 1971). Xanthium strumarium is a polymorphic taxon that produces at least eight major sesquiterpene lactones and has received various taxonomic treatments (Millspaugh and Sherff, 1919; Wilder, 1923; Love and Dansereau, 1959). We apply

https://www.jstor.org/stable/pdfplus/2441576.pdf

Tom J. Mabry

Papers

Flavonoids from Brickellia scoparia

Systematic implications of flavonoids in Hazardia

Experimental hybridization of xanthium strumarium (compositae) from asia and america. ii. sesquiterpene lactones of f 1 hybrids

Psilostachyin, a new type of sesquiterpene lactone

Sesquiterpenes from Lepechinia urbaniana