Distribution of Biflavonoids

A summary of the distribution of biflavonoids in woody plants is provided in Tables 7.6.1 through 7.6.4. References have been selected to demonstrate more specific distribution of biflavonoids by plant species. More detailed listings of the occurrences of these compounds in all plants as well as of known synthetic products up to 1981 are provided in the reviews prepared by Geiger and Quinn (125, 126). 

Group Class Common name Substitution Occurrence Reference 

The biflavonoids have usually been isolated from leaf tissues, although fruit and bark are also commonly good sources of these compounds. The biflavonoids are less commonly isolated from wood, but the heartwood of Garcinia spp. is exceptional as a source of particularly interesting compounds. 

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There has been no available data on the absorption and distribution of biflavonoids in animals/humans. Morelloflavone (159) and 1-2,3,11-2,3-tetrahydroamentoflavone (47) showed in vivo anti-inflanunatoiy activity by oral administration. [27, 28] However, in some studies, oral treatment produced much reduced or no activity, suggesting that the oral bioavailability of biflavonoids may be very low. [3, 29] In contrast, intraperitoneal administration resulted in higher anti-inflammatory activity. Topical treatment also yielded positive results. [30-33]... 

Table 7.6.2. Distribution of biflavonoids cupressuflavones, agathisflavones and succedaneaflavone... 

Table 7.6.3. Distribution of biflavonoids taiwaniaflavones, volkensiflavones, and chamaejasmin... 

Historically, reviews of benzophenones were included as small sections with the biogenetically related xanthones. Previous reviews include Bennett and Lee [1] who discussed the distribution and isolation of 20 benzophenones included in a review focused on xanthones. They also discussed the biosynthetic relationships between xanthones and benzophenones. Kumar and Baslas [2] summarized the chemical composition, medical importance, and biologically active benzophenones, biflavonoids, and xanthones isolated from Garcinia species. Two reviews by Waterman focused on the chemotaxonomic significance of benzophenones, along with biflavonoids and xanthones, of ten African Garcinia species [3,4], Locksley and Murray [5] discussed the distribution of thirteen benzophenones in higher plants and Sultanbawa [6] included five benzophenones in a review on xanthonoids from tropical plants. Sultanbawa also discussed the biosynthesis of benzophenones and xanthones. Erdelmeier et al. [7] discussed 20 polyprenylated benzophenones in a chapter on the various properties of St. John s Wort Hypericum perforatum). 

The natural sources, biological activities, and traditional uses of all biflavonoids mentioned above are compressed in Table 1. In this way a current picture of their distribution is achieved, thus providing an important tool for future brflavonoid studies. The structures are mainly distributed in some species of Angiosperms (monocots and dicots), Gymnosperms, ferns (Pteridophyta), and mosses (Bryophyta). 

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