Hydroxypipecolic acids and hydroxyprolines as chemical characters in Aphanocalyx, Bikinia and Tetraberlinia (Leguminosae: Caesalpinioideae): support for the segregation of Monopetalanthus

The presence or absence of hydroxypipecolic acids and hydroxyprolines in leaves of members of the former genus Monopetalanthus Harms was generally found to support the recent segregation of species into Aphanocalyx Oliver, Bikinia Wieringa and Tetraberlinia (Harms) Hauman. The species transferred to Aphanocalyx were found to lack these non-protein amino acids, like species traditionally placed in that genus, while most of the species reclassified into the new genus Bikinia accumulated hydroxypipecolic acids and hydroxyprolines (the exceptions were B. aciculifera Wieringa, B. coriacea J. Morel ex Aubrév. and B. durandii F. Hallé & Normand). All seven known species of Tetraberlinia, including T. longiracemosa (A. Chev.) Wieringa, which was formerly placed in Monopetalanthus, also contained one or both types of compounds. In species of Bikinia and Tetraberlinia the hydroxypipecolic acids accumulated included trans-4-hydroxypipecolic acid, trans-4-trans-5-dihydroxypipecolic acid and cis-4-cis-5-dihydroxypipecolic acid. All except T. moreliana Aubrév. and T. korupensis Wieringa also accumulated N-methyl-trans-4-hydroxyproline and both of these species and T. bifoliolata (Harms) Hauman accumulated an epimer of N-methyl-4,5-dihydroxypipecolic acid. These chemical groupings of Tetraberlinia species are generally in accordance with those based on morpholog

Variations in lipophilic and vacuolar flavonoids among European Pulicaria species

Four European Pulicaria species, P. odora, P. paludosa, P. sicula and P. vulgare, were analysed for their surface and vacuolar constituents for comparison with previous data obtained for P. dysenterica. Each species had a distinct flavonoid pattern with notable differences between leaf and inflorescence. 6-Hydroxyflavonols were the major lipophilic components in all of the species and tissues except in the leaves of P. paludosa and P. vulgare, where scutellarein 6-methyl ether was the main constituent. In the leaves of P. sicula a more unusual flavone, 6-hydroxyluteolin 5,6,7,3′,4′-pentamethyl ether, was a major component. Pulicaria odora was distinguished by the presence of a series of methylated 6-hydroxykaempferol derivatives including a 3,5,6,7,4′-pentamethyl ether. Quercetagetin hexamethyl ether occurred in both tissues of P. sicula together with the 3,7,3,4′-tetra methyl ether and other quercetagetin derivatives, which were 5-methylated. Quercetagetin 3,7,3′-methyl ether was present in all species except P. odora. Flavonol glucuronides were characteristic vacuolar constituents of all the taxa studied. Two rare glycosides, patuletin and 6-hydroxykaempferol 6-methyl ether 7-glucuronides were identified in the inflorescence of P. odora. Pulicaria vulgaris, a rare plant of southern England, had the vacuolar flavonoid profile most similar to the other more abundant British plant, P. dysenterica

A chemosystematic study of the genus Gomphostemma and related genera (Lamiaceae)

Species in the genera Gomphostemma, Chelonopsis and Bostrychanthera were systematically studied with reference to their flavonoid and phenolic acid compounds in order to investigate whether the profiles of these compounds would support a classification of the genus and related genera based on morphological characters. Thirty-five flavonoid glycosides, eight phenolic acids and derivatives were identified by LC-UV-MS/MS analysis of aqueous 80% MeOH extracts on the basis of their UV and mass spectra, retention times and comparison with in-house library. The occurrence of individual compounds was not particularly informative in Gomphostemma, although the overall chemical profile supported G. subgen. Pogosiphon and vicenin-2 was a characteristic component of Gomphostemma leptodon and Gomphostemma curtisii. In contrast, the flavonoids and phenolic acids of Chelonopsis were informative at infrageneric level. Glycosides of 6-substituted flavones were well represented in Ch. subgen. Aequidens, including Ch. forrestii, Ch. rosea, Ch. odontochila, Ch. lichiangensis and C. giraldii. A dicaffeoylquinic acid was produced in Ch. subgen. Chelonopsis, (for example, in Ch. longipes and Ch. Moschata), but absent from Ch. subgen. Aequidens. The same dicaffeoylquinic acid was also found in the genus Bostrychanthera and suggests a close relationship with Ch. subgen. Chelonopsis, in agreement with a recent DNA based phylogeny. There is correlation between trichome type and phenolic acid compound distribution in Chelonopsis, but this is not observed in Gomphostemma