A chemosystematic investigation on Ipomopsis

The diminutive North American desert annual species of Ipomopsis, Section Microgilia, I. depressa and I. polycladon, agree with other members of the genus in having a flavonoid syndrome based upon 6-methoxyflavonols. Patuletin is the predominant aglycone present but traces of eupatolitin and eupalitin were detected. In I. polycladon, four glycosides of patuletin and one of eupalitin were isolated and identified.     

Flavonoid variation in Cannabis L.

Fifty-three individual plants of Cannabis saliva L., grown from seed obtained from nine countries, were analyzed for their flavonoid constituents. Compounds present were the C-glycoflavones vitexin, orientin, cytisoside, and an 0"-glucoside of each. A C-glycuronide of luteolin was detected in several plants. Kaempferol and quercetin-3-0-diglucosides were also seen in many specimens. The distribution of compounds supported the subspecific treatment of the genus suggested by Small & Cronquist (1976). The data were less helpful in resolving trends amongst the varieties recognized by those authors. A considerable amount of plant to plant variation was observed.     

Monophyly and generic relationships of polemoniaceae based on matK Sequences

Polemoniaceae are often considered a model family for studying evolutionary processes, yet a reliable phylogeny for the family is only now beginning to emerge. To test the monophyly of this family and to elucidate intergeneric relationships, we employed comparative sequencing of the chloroplast gene matK. Parsimony analysis of matK sequences representing 18 genera of Polemoniaceae and nine families from Asteridae sensu lato places Polemoniaceae apart from Solanaceae near Fouquieriaceae, Ericaceae, Sarraceniaceae, and Diapensiaceae. Both this and a subsequent analysis of 59 species of Polemoniaceae indicate that Cobaea is derived from within Polemoniaceae, rather than being the sister to Polemoniaceae as suggested by some authors. The tropical genera Bonplandia, Cantua, and Cobaea form a clade, and the remaining, primarily temperate genera, excluding Acanthogilia, form a second monophyletic group. Acanthogilia is placed ambiguously as sister to either the tropical or temperate groups depending on the location of the root for Polemoniaceae. Within the temperate lineage, Polemonium is sister to three large clades: a well-supported clade comprising Phlox, Gymnosteris, Linanthus, Leptodactylon, and Gilia filiformis; a moderately well-supported clade comprising Allophyllum, Collomia, Navarretia, and several species of Gilia; and a weakly supported clade comprising Eriastrum, Ipomopsis, Langloisia, Loeseliastrum, Loeselia, and several species of Gilia. In addition to revealing the extreme polyphyly of Gilia, this analysis suggests that Ipomopsis and Linanthus are also polyphyletic.     

Correlations between anthocyanin chemistry and pollination ecology in the polemoniaceae

A study of the anthocyanins in a representative sample (34 species from 14 genera) of Polemoniaceae has shown that the pigment type in the flowers is broadly correlated with pollination ecology. Thus, hummingbird pollinated species such as Ipomopsis aggregata generally contain pelargonidin sometimes with cyanidin, while bee and beefly pollinated species (e.g. Gilia latiflora) contain mainly delphinidin. On the other hand, lepidopteran species such as Leptodactylon californicum have cyanidin or mixtures of cyanidin with delphinidin. The above three anthocyanidins occur usually as the 3-glucoside, 3,5-diglucoside, $\text{3-(p-}\text{coumarylglucoside}\text{)}$ and $\text{3-(p-}\text{coumarylglucoside}\text{)-5-}\text{glucoside}$, although other types are occasionally found. The distribution of glycosidic types and of acylation, unlike that of the anthocyanidins, is more closely correlated with systematic position than with pollinating vectors. In autogamous species where animal pollination is absent or unimportant, anthocyanin pigmentation in the flowers retains the complexity present in related animal-pollinated taxa. Anthocyanins were also identified in hummingbird pollinated plants from two related families and pelargonidin derivatives were detected. In Fouquieria splendens (Fouquieriaceae), the glycosidic pattern was different from that in Polemoniaceae in being 3-galactoside. In Penstemon (Scrophulariaceae) a study of flower anthocyanins was consistent with Straw's hypothesis that the wasp-pollinated P. spectabilis originated by hybridization between the hummingbird-pollinated P. centranthifolius and the bee-pollinated P. grinnellii.     

Flavonoid patterns in Leptodactylon and Linanthus

Twenty-seven flavonoids were found among three species of Leptodactylon and sixteen species of Linanthus, of which only three were identical between the two genera. This argues strongly for the maintenance of two genera; however, the underlying similarities in coumarins, flavonol glycosides, chrysoeriol and glycoflavones suggest that the two genera are closely related. The flavonoid data also suggest that Leptodactylon and Linanthus of the tribe Gilieae may actually be closer to Phlox and Microsteris of the tribe Polemonieae, than to other Gilieae.     

Flavonoid and anthocyanin patterns and the systematic relationships in Collomia

Analyses of extracts among populations of the 14 species of Collomia revealed the occurrence of 13 mono-, di- and triglycosides based on the flavonoids, acacetin, kaempferol, patuletin and quercetin. The glycosides included those having arabinose, galactose, glucose and rhamnose as mono-, bio- or triosides at the 3-, 5-, 3,7- or 7-position. Analyses of floral extracts from ten species revealed the occurrence of two anthocyanins, cyanidin and delphinidin 3-(p-coumarylglucosyl)-5-glucoside. Nearly all the species express distinctive flavonoid patterns, although the differences are based on relatively minor changes in position or type of glycosidic substitution. Use of the minimum biosynthetic step distance (MBSD), an index of similarity, revealed that a mean of 5.6 steps separated the 14 species. The four perennial species of section Collomiastrum showed a high degree of similarity and differed consistently from species of the two annual sections Courtoisia and Collomia by lacking quercetin-5-glucoside and kaempferol-3-arabinosylgalactoside. In contrast, flavonoid patterns among species within sections Courtoisia and Collomia showed a relatively low degree of similarity. The dissimilarity between C. diversifolia and C. heterophylla (section Courtoisia) is consistent with their divergent patterns of pollen morphology and ecological distribution. Three groups of species within section Collomia were defined generally by shared patterns of flavonoids, which are correlated to some degree with floral, pollen and vegetative morphology.     

Flavonoid patterns in the Prosopis juliflora complex

Five species in the Prosopis juliflora complex, as well as two varieties and putative hybrid, were found to have similar flavonoid patterns. A total of 21 flavonoids were detected and 12 major compounds were identified. No flavonoid correlations with ecotypes were observed.     

Chemotaxonomic Studies in Ferula of China on the Basis of Flavonoids

Sixteen species of Ferula L. (Umbelliferae) were examined for their leaf flavonoids, and at least 9 glycosides of quercetin, kaempferol and apigenin are detected in 13 species. While most of the constituents reported are common in the Umbelliferae, the unusual one, apigenin-6, 8-C-diglucoside, which was found in Ostericum Hoffm. in an earlier survey has been detected in F. moschata (F. sumbul) The three species (F. sinkiangensis, F. fukangensis and F. krylovii) from which flavonoids have not been found, are all medicinal plants with strong garliky odor due to a high concentration of essential oils containing disulfides. The subgenus Peucedanoides is found to be rich in quercetin glycosides, and the aglycon pattern seems to have some relationship with habitat conditions in the genus: the species occurring in comparatively humid habitats are often large herbs and often characterized by the presence of quercetin, while those growing in dry habitats contain apigening kaepferol, as well as quercetin. Nevertheless, any conclusion with certainty needs examining more species of the genus. It is interesting to note that F. moschata, from which the glycosylapigenin was found, and F. pseudooreoselinum, which probably has a trace amount of kaempferol glycoside, are peculiar in Ferula in their inflorescence morphology. The phytochemic results also raise a suspicion against their systematic position within the genus. F. bungeana, previously placed in the subgenus Peucedanoides, has relatively great similarities with F. syreitschkowii of the subgenus Narthex in their general morphology and fruit anatomy. In the present survey apigenin-7-glycoside is detected from both, and thus it seems more suitable to transfer the former species into the subgenus Narthex. The same compounds have been found in F. licentiana and F. tunshanica, which also share the characters of morphology and anatomy. The fact does support the view that the lattershould be included in F. licentiana as a variety.     

Flavonoid variation in Melampodium

Five species of Melampodium have been studied for their flavonoid components. Melampodium aureum, M. divaricatum and M. longipilum exhibited simple arrays of kaempferol and quercetin 3-O-mono-and diglycosides. Melampodium bibracteatum afforded the same simple glycosides plus quercetagetin 3-methyl ether. Melampodium americanum had the most complex pattern with simple flavonol glycosides being accompanied by five O-methylated derivatives of quercetagetin plus 6-hydroxykaempferol 3-methyl ether. Three populations of M. bibracteatum gave identical flavonoid profiles as did 15 collections of M. bibracteatum.     

Flavonoid sulphates in the Umbelliferae

A survey of over 250 representative taxa in the Umbelliferae has shown that sulphates only accumulate in three genera, Ammi, Daucus and Oenanthe. The presence of quercetin, rhamnocitrin, rhamnetin and isorhamnetin 3-sulphate in Ammi visnaga serves to distinguish it from the related A. majus which lacks sulphates. In Daucus carota leaf, the 7-and 4′-sulphates of luteolin both occur; the two characters are polymorphic and appear to be present more frequently in North temperate than in South temperate populations. Oenanthe is the only genus where sulphates are found abundantly; they occur in 7 of 9 species surveyed. In addition to the known isorhamnetin 3sulphate of O. stolonifera, quercetin 3-sulphate and luteolin 7-sulphate were identified for the first time in the genus. The synthesis of various kaempferol and quercetin sulphates is described.     

Flavonoid diversification in Achillea ptarmica and allied taxa

More than 50 collections of 12 species forming the A. ptarmica group have been analysed for their leaf flavonoids. C-Glycosylflavones (iso-orientin and derivatives, vicenins and lucenins) were found to be the main components, whereas flavonol 3-O-glycosides (based on quercetin and kaempferol) and flavone 7-O-glycosides (based on luteolin and diosmetin) were of restricted distribution. Infraspecific variability regarding C-glycosylflavones was observed in most of the taxa investigated. By contrast, flavonol 3-O-glycosides appeared to be stable characters and were sometimes accumulated instead of C-glycosylflavones. In addition to the flavonoids, the geographical distribution patterns and the possible origin of the A. sibirica in Eastern Asia are briefly discussed.     

Flavonoid variation in some North Americna Saxifraga species

Eight species of Saxifraga representing sections Micranthes, Hirculus, Dactyloides and Xanthizoon were studied for their flavonoids (S. california, S. integrifolia, S. michauxii, S. ferruginea, S. eschscholtzii, S. hirculus, S. caespitosa and S. aizoides). The major compounds present in most species were kaempferol and quercetin monogluocosides and galactosides. Glucosides of kaempferol and quercetin predominate in the first four species listed, while galactosides of quercetin and myricetin are dominant in the lastthree. 3-O-Methyl- and 3,3′-di-O-methylquercetin were identified from S. californica and S. integrifolia. Saxifraga caespitosa synthesizes a complex mixture of O-methylated flavonols as well as a novel O-methylated dihydrokaempferol.Species pairs S. michauxii/S. ferruginea and S. californica/S.integrifolia exhibit close flavonoid similarity which may reflect their morphological similarities.     

Flavonol and dihydroflavonol glycosides of echinocereus triglochidiatus var. Gurneyi

Perianth parts, in particular, tepals of Echinocereus triglochidiatus var. gurneyi yielded a complex mixture of dihydroflavonols and dihydroflavonol 7-O-glucosides. Dihydroquercetin and its 7-O-glucoside were the predominant compounds while dihydrokaempferol and dihydromyricetin and their 7-O-glycosides were present in lesser amounts. Quercetin 7-O-glucoside was the principal flavonol glycoside: others present were quercetin and kaempferol 3-O-glucosides and 3-O-rhamnosylglucosides. The epidermis and spines yielded only traces of presumed flavonols as determined by two-dimensional TLC. No flavonoids were detected in the cortex tissue. This is the first report of dihydroflavonol derivatives from the Cactaceae and constitutes the first record of flavonoids from Echinocereus.     

Flavonoids of Leptarrhena pyrolifolia

The flavonoids of Leptarrhena pyrolifolia comprise (+)-dihydromyricetin and mono-, di-and triglycosides of kaempferol, quercetin, isorhamnetin and myricetin. This is the first report of a dihydroflavonol in the Saxifragaceae.     

Flavonoid distribution patterns in Leucanthemum and related species from North Africa

Flavonoid data is reported for 16 species including eight species of Leucanthemum from North Africa, four from Europe and related species in the Chrysanthemum-Leucanthemum complex. Flavonols, especially quercetin, isorhaamnetin, kaempferol, patuletin and spinacetin, are predominant in the North African species. Flavones, which are common in Leucanthemum species in Europe, are of very rare occurrence in the North African species. The relationship of the species based on the distribution of flavonoid glycosides and aglycones from the ray florets is discussed.     

Chemosystematics in the Rutaceae: A chemotaxonomic survey of flavonoids and monoterpenes in leaves of Acmadenia species

By means of thin layer chromatography and gas liquid chromatography the distribution of monoterpenes and flavonoid aglycones in the leaves of 19 samples of 15 species of Acmadenia has been investigated. The distribution of flavonol and flavone aglycones shows a close agreement with recently proposed taxonomic divisions within the genus. It is proposed that these patterns may be of importance in interpreting the evolutionary development of the genus.     

Quercetagetin 6,7,4′-trimethyl ether and 3-sulphate from Decachaeta haenkeana

Four 6-methoxylated flavonols, including a new quercetagetin derivative and its 3-potassium sulphate salt, were isolated from the aerial parts of Decachaeta haenkeana.     

A further survey of anthocyanins and other phenolics in Ilex and Euonymus

A survey of 27 plants of Ilex and Euonymus revealed that the distribution of anthocyanins and cinnamic acid esters in their fruits is correlated with accepted taxonomic classification. In the skin of the fruit, the 3-xylosylglucoside of cyanidin and pelargonidin and the 3-monoglucoside of cyanidin were identified, and the hydrolysed fruit-extracts were found to contain quercetin, kaempferol and caffeic acid. The genus Ilex has been shown to be distinguishable from the genus Euonymus by their anthocyanins; I. micrococca was exceptional in having only chrysanthemin. Additionally, chlorogenic and isochlorogenic acids and caffeylglucose occur in Ilex but not in Euonymus. The microspectrophotometric examination of the pigment cells of the black- and red-Ilex fruits revealed that the position of absorption maxima in the visible region is mainly related to the relative amounts of anthocyanin and flavonol present.     

Flavonoids from Artemisia ludoviciana var. ludoviciana

Nineteen flavonoids were isolated from Artemisia ludoviciana var. ludoviciana, including a new 2′- hydroxy- 6-methoxyflavone, 5,7,2′,4′-tetrahydroxy-6,5′-dimethoxyflavone. The known compounds include quercetagetin 3,6,3′,4′-tetramethyl ether, eupatilin, 5,7-dihydroxy-3,6,8,4′-tetramethoxyflavone, luteolin 3′,4′-dimethyl ether, jaceosidin, 5,7,4′-trihydroxy-3,6-dimethoxyflavone, tricin, hispidulin, chrysoeriol, kaempferol 3-methyl ether, apigenin, axillarin, eupafolin, selagin and luteolin together with three flavones which were previously isolated for the first time from Artemisia frigida: 5,7,4′-trihydroxy-6, 3′,5′-trimethoxyflavone, 5,7,3′-trihydroxy-6,4′,5′-trimethoxyflavone and 5,7,3′,4′-tetrahydroxy-6,5′- dimethoxyflavone.     

Flavonoid glycosides from illuminated cell suspension cultures of Petroselinum hortense

Twenty-four different flavonoid glycosides were isolated from illuminated cell suspension cultures of parsley (Petroselinum hortense). The chemical structures of fourteen of these compounds were further characterized. The aglycones identified were the flavones apigenin, luteolin and chrysoeriol, and the flavonols quercetin and isorhamnetin. The flavones occurred either as 7-O-glucosides or as 7-O-apioglucosides, while the flavonols were 3-O-monoglucosides or 3,7-O-diglucosides. One-half of these glycosides were electrophoretically mobile and substituted with malonate residues.