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Two novel delphinidin 3-(tri or di)-glycoside-7-glycosides were isolated from the violet–blue flowers of Vinca minor L. and V. major L. (Family: Apocynaceae), and determined to be delphinidin 3- O -[2- O -(β-xylopyranosyl)-6- O -(α-rhamnopyranosyl)-β-galactopyranoside]-7- O -(α-rhamnopyranoside) [= delpphinidin 3-(2 G -xylosylrobinobioside)-7-rhamnoside] as major floral anthocyanin of V. minor and delphinidin 3- O -[6- O -(α-rhamnopyranosyl)-β-galactopyranoside]-7- O -(α-rhamnopyranoside) [= delpphinidin 3-robinobioside-7-rhamnoside] as major floral anthocyanin of V. major by chemical and spectroscopic methods. In addition, chlorogenic acid and kaempferol 3- O -[6- O -(α-rhamnopyranosyl)-β-galactopyranoside]-7- O -(α-rhamnopyranoside) [= kaempferol 3-robinobioside-7-rhamnoside (robinin)] were identified in these flowers. In this paper, the relation between the structure of floral anthocyanins and classification of Vinca species was discussed. [ABSTRACT FROM AUTHOR]

Dahlias (Dahlia variabilis) exhibit a wide range of flower colours because of accumulation of anthocyanin and other flavonoids in their ray florets. Two lateral mutants were used that spontaneously occurred in ‘Michael J’ (MJW) which has yellow ray florets with orange variegation. MJOr, a bud mutant producing completely orange ray florets, accumulates anthocyanins, flavones, and butein, and MJY, another mutant producing completely yellow ray florets, accumulates flavones and butein. Reverse transcription–PCR analysis showed that expression of chalcone synthase 1 (DvCHS1), flavanone 3-hydroxylase (DvF3H), dihydroflavonol 4-reductase (DvDFR), anthocyanidin synthase (DvANS), and DvIVS encoding a basic helix–loop–helix transcription factor were suppressed, whereas that of chalcone isomerase (DvCHI) and DvCHS2, another CHS with 69% nucleotide identity with DvCHS1, was not suppressed in the yellow ray florets of MJY. A 5.4 kb CACTA superfamily transposable element, transposable element of Dahlia variabilis 1 (Tdv1), was found in the fourth intron of the DvIVS gene of MJW and MJY, and footprints of Tdv1 were detected in the variegated flowers of MJW. It is shown that only one type of DvIVS gene was expressed in MJOr, whereas these plants are likely to have three types of the DvIVS gene. On the basis of these results, the mechanism regulating the formation of orange and yellow ray florets in dahlia is discussed. [ABSTRACT FROM PUBLISHER]

Two 6-hydroxypelargonidin glycosides were isolated from the orange–red flowers of Alstroemeria cultivars, and determined to be 6-hydroxypelargonidin 3-O-(β-d-glucopyranoside) and 3-O-[6-O-(α-l-rhamnopyranosyl)-β-d-glucopyranoside], respectively, by chemical and spectroscopic methods. In addition, five known anthocyanidin glycosides, 6-hydroxycyanidin 3-malonylglucoside, 6-hydroxycyanidin 3-rutinoside, cyanidin 3-malonylglucoside, cyanidin 3-rutinoside and pelargonidin 3-rutinoside were identified in the flowers. [Copyright &y& Elsevier]

A rare anthocyanin, malvidin 3- O -rhamnoside, was isolated from the blue flowers of Parochetus communis Buch.-Ham. ex D. Don along with two known flavonols: kaempferol 3- O -(2- O -glucosyl-6- O -rhamnosyl)-glucoside and kaempferol 3- O -(2,6-di- O -rhamnosyl)-glucoside. These structures were identified using Nuclear Magnetic Resonance (NMR) and Mass Spectrometry (MS). Image 1 • This study investigated the anthocyanin and flavonols found the blue flowers of Parochetus communis. • Kaempferol glycosides and malvidin 3-rhamnoside were identified as major floral flavonoids. • This is the first report on kaempferol glycosides identified from P. communis flowers. [ABSTRACT FROM AUTHOR]

Four new acylated anthocyanins were isolated from the violet-blue and purple-violet flower cultivars of Lobelia erinus L., along with five known anthocyanins and two known flavones. The four novel acylated anthocyanins were determined to be delphinidin 3- O -[6- O -(4- O -(trans - p -coumaroyl)-α-rhamnopyranosyl)-β-glucopyranoside]-5- O -[6- O -(malonyl)-β-glucopyranoside]-3′- O -[6- O -(trans -caffeoyl)-β-glucopyranoside]-5′- O -(β-glucopyranoside) (2), delphinidin 3- O -[6- O -(4- O -(cis - p -coumaroyl)-α-rhamnopyranosyl)-β-glucopyranoside]-5- O -[6- O -(malonyl)-β-glucopyranoside]-3′,5′-di- O -[6- O -(trans -caffeoyl)-β-glucopyranoside](5), cyanidin 3- O -[6- O -(4- O -(trans - p -coumaroyl)-α-rhamnopyranosyl)-β-glucopyranoside]-5- O -[6- O -(malonyl)-β-glucopyranoside]-3′- O -[6- O -(trans -caffeoyl)-β-glucopyranoside](7), and cyanidin 3- O -[6- O -(4- O -(trans - p -coumaroyl)-α-rhamnopyranosyl)-β-glucopyranoside]-5- O -[6- O -(malonyl)-β-glucopyranoside]-3′- O -[6- O -(trans -feruloyl)-β-glucopyranoside](9), using chemical and spectroscopic methods. Using spectroscopy, the visible absorption curves obtained from fresh violet-blue and purple-violet petals indicated the presence of poly acylated anthocyanins in these plants. Two strong absorption maxima from seven violet-blue cultivars were observed at 614 and 570 nm, which included delphinidin based poly acylated anthocyanins, and two absorption maxima from two purple-violet cultivars were observed at 588 and 552 nm, which were included cyanidin based poly acylated anthocyanins. The violet-blue cultivars contained pigment 4 as a major anthocyanin and purple-violet cultivars contained pigment 7 as a major anthocyanin. All cultivars contained apigenin 7-rutinoside (F2) as a major flavone in their petals. The spectra of purified pigments 4 and 7 in pH 5.0 buffer solution and the spectra obtained by adding F2 to respective solutions containing pigments 4 and 7 showed nearly identical curves, respectively. Moreover, under the same pH conditions, the spectra of pigments 4 and 7 and the spectra of violet-blue and purple-violet petals showed nearly identical curves, respectively. These results suggested that the violet-blue and purple-violet flower cultivars containing poly acylated anthocyanins are affected by intramolecular co-pigmentation under weak acid conditions but are not affected by intermolecular co-pigmentation. Image 1 • New anthocyanins were isolated from the flowers of Lobelia erinus. • The structures were elucidated on the basis of chemical and spectroscopic data. • Flower color of Lobelia erinus was demonstrated by the intramolecular co-pigmentation. [ABSTRACT FROM AUTHOR]

Flower color is one of the most important properties of ornamental flowers. Information on the kinds of pigments that flowers can biosynthesize is useful for breeding cultivars focused on flower colors. The flower colors of regular ornamental delphinium cultivars are blue, violet, purple, pink, and white. The pigments of these flowers are delphinidin-based anthocyanins. It has been reported that the typical modification in delphinium anthocyanins involves the transfer of glucose and p -hydroxybenzoic acid molecules to the 7-position of delphinidin one by one, and it was predicted that other unidentified anthocyanins are present in addition to the already reported ones. Recently, light pink flowers that accumulate pelargonidin-based anthocyanins were reported from cultivars derived from Delphinium grandiflorum. Converting delphinidin-based anthocyanins to pelargonidin-based ones is considered key to producing red flowers in delphinium. Hence, we investigated anthocyanins of blue, mauve, light pink, and white flowers of D. grandiflorum cultivars. We isolated anthocyanins and analyzed them using HPLC, TLC, UV–vis spectra, FABMS, and NMR. Using these methods, we identified two novel delphinidin-based anthocyanins and three novel pelargonidin-based anthocyanins: delphinidin 3- O -[6- O -(α-rhamnopyranosyl)-β-glucopyranoside]-7- O -[6- O -(p -hydroxybenzoyl)-β-glucopyranoside] (2), pelargonidin 3- O -[6- O -(α-rhamnopyranosyl)-β-glucopyranoside]-7- O -[6- O -(4- O -(6- O -(p -hydroxybenzoyl)-β-glucopyranosyl)- p -hydroxybenzoyl)-β-glucopyranoside] (5 , rubrodelphin), pelargonidin 3- O -[6- O -(α-rhamnopyranosyl)-β-glucopyranoside]-7- O -[3- O -(β-glucopyranosyl)-6- O -(4- O -(6- O -(p -hydroxybenzoyl)-β-glucopyranosyl)- p -hydroxybenzoyl)-β-glucopyranoside] (6), delphinidin 3- O -[6- O -(α-rhamnopyranosyl)-β-glucopyranoside]-7- O -[3- O -(3- O -(6- O -(p -hydroxybenzoyl)-β-glucopyranosyl)-β-glucopyranosyl)-6- O -(4- O -(6- O -(p -hydroxybenzoyl)-β-glucopyranosyl)- p -hydroxybenzoyl)-β-glucopyranoside] (7), and pelargonidin 3- O -[6- O -(α-rhamnopyranosyl)-β-glucopyranoside]-7- O -[3- O -(3- O -(6- O -(4- O -(6- O -(p -hydroxybenzoyl)-β-glucopyranosyl)- p -hydroxybenzoyl)-β-glucopyranosyl)-β-glucopyranosyl)-6- O -(4- O -(6- O -(p -hydroxybenzoyl)-β-glucopyranosyl)- p -hydroxybenzoyl)-β-glucopyranoside] (9 , rosedelphin), along with four known anthocyanins. The flowers of five blue cultivars accumulated cyanodelphin (8) as the dominant pigment. The shapes of visible absorption spectra of these five blue flowers were similar, indicating that the color and the absorption spectra were the typical ones for delphinium blue color produced by 8. The mauve flower color was due to a mixture of delphinidin-based anthocyanins in various polyacylated levels at the 7-position. The light pink flowers accumulated pelargonidin-based anthocyanins 5 , 6 , and 9. These pigment structures showed that the pelargonidin-based anthocyanins modified in the same way as in the originally biosynthesized delphinidin-based anthocyanins even though aglycone was replaced by pelargonidin in these anthocyanins. [Display omitted] • Anthocyanins in flowers of Delphinium grandiflorum cultivars were investigated. • Isolated anthocyanins were characterized by chemical and spectroscopic analyses. • Two delphinidin-based and three pelargonidin-based anthocyanins were newly identified. • A consistent modification pattern was discovered in the two types of anthocyanins. • The relationship between flower color and anthocyanin component was discussed. [ABSTRACT FROM AUTHOR]

Identified anthocyanins from the flowers of Nigella damascena. • Flavonoids in flowers of Nigella damascena L. (Ranunculaceae) were investigated. • Isolated anthocyanins were characterized by chemical and spectroscopic analyses. • The predominant anthocyanin was anthocyanidin 3-[2-(xylosyl)-6-(rhamnosyl)-glucoside]. • This is a first report of cyanidin 3-[2-(glucuronosyl)-6-(rhamnosyl)-glucoside]. • Also, a first report of 7-methyldelphinidin 3-[2-(xylosyl)-6-(rhamnosyl)-glucoside]. Nigella damascena L. is an annual plant belonging to the buttercup family Ranunculaceae, commonly known as love-in-a-mist. It is used as a garden plant. The flowers are blue, pink, or white. In order to determine the pigments responsible for the flower colors of N. damascena , the anthocyanins and flavonols in the rose-pink, blue, and white flowers of N. damascena were investigated using cultivars of the 'Miss Jekyll' series. The identities and structures of compounds were determined by chemical and spectroscopic analyses. Four cyanidin 3-glycosides were detected and identified from the rose-pink flowers. In the blue flowers, one major anthocyanin and several minor anthocyanins were detected. The identities of the major and one minor anthocyanin were determined. The main anthocyanins in the rose-pink and the blue flowers were cyanidin 3-[2-(xylosyl)-6-(rhamnosyl)-glucoside] and 7-methyldelphinidin 3-[2-(xylosyl)-6-(rhamnosyl)-glucoside], respectively. Petunidin 3-[2-(xylosyl)-6-(rhamnosyl)-glucoside] had been previously reported as the major anthocyanin from the blue flowers, however, any petunidin-type anthocyanins were not found from the blue flowers. Cyanidin 3-[2-(glucuronosyl)-6-(rhamnosyl)-glucoside], one of minor anthocyanins in the rose-pink flowers, and 7-methyldelphinidin 3-[2-(xylosyl)-6-(rhamnosyl)-glucoside] are reported for the first time. This is the second report of an anthocyanin of the 7-methyldelphinidin type, following that from Catharanthus roseus flowers. The white-flower cultivar contained anthocyanins analogous to those of the blue flowers but at very low levels. The same three flavonols were detected in the rose-pink, blue, and white flowers. [ABSTRACT FROM AUTHOR]

R2R3-MYB transcription factors are known to activate the flavonoid biosynthetic pathway. In the present study, R2R3-MYB gene isolated from the liliaceous ornamental plant Tricyrtis sp. ( TrMYB1 ) under the control of the cauliflower mosaic virus 35S promoter was introduced into Pelargonium crispum via Agrobacterium -mediated transformation in order to alter leaf color phenotype. Ten independent transgenic plants have been obtained, and they could be classified into three types according to the leaf color phenotype: six transgenic plants had deep yellowish-green leaves as non-transgenic plants (Type I); two had deep red-purple leaves (Type II); and two had deep red leaves (Type III). Spectrophotometric analysis showed that the amount of total anthocyanins significantly increased in leaves of Type II and Type III transgenic plants compared with non-transgenic and Type I transgenic plants. In addition, several anthocyanins were newly produced in leaves of Type II and Type III transgenic plants as revealed by high performance liquid chromatography analysis. Quantitative real-time reverse transcription-polymerase chain reaction analysis showed that TrMYB1 expression level correlated with the degree of leaf color alteration. Our results indicate the validity of genetic transformation with TrMYB1 for producing colored foliage in heterologous ornamental plants. [ABSTRACT FROM AUTHOR]

Highlights: [•] Anthocyanins in the various flower-color cultivars of Ipomoea tricolor were surveyed. [•] All cyanic flowers contain anthocyanidin 3-sophoroside-5-glucosides derivatives. [•] A common glycosyl pattern was found despite the difference in flower pigmentation. [•] Three anthocyanins new to I. tricolor were isolated from a cultivar. [ABSTRACT FROM AUTHOR]