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Betacyanins from cell cultures of Phytolacca americana were characterized and compared with those of the stems and ripening fruits of the plant. Whereas in fruits prebetanin (betanin 6'-O-sulphate) and its isoform predominate, in the stem and cell cultures feruloylated derivatives occur as the major components. These were rigorously identified by various spectroscopic techniques (DAD-HPLC, NMR, LC-MS and electrospray MS-MS) and carbohydrate analyses as betanidin 5-O-[(5"-O-E-feruloyl)-2'-O-beta-D-apiofuranosyl] -beta-D-glucopyranoside, a new betacyanin of higher plants, and betanidin 5-O-(6'-O-E-feruloyl)-beta-D-glucopyranoside (lampranthin II), together with their isoforms.

Betacyanins from the bracts of Bougainvillea glabra were isolated and characterized by a combination of spectroscopic techniques (DAD-HPLC, NMR, LC-MS, GC-MS, electrospray MS, tandem MS) as gomphrenin I (betanidin 6-O-beta-glucoside) and various derivatives of bougainvillein-v (betanidin 6-O-beta-sophoroside), i.e. mono- and diglucosylsophorosides which are acylated with 4-coumaric and caffeic acid (mono- and diesters). Besides the betacyanins, B. glabra bracts accumulated large amounts of flavonols (kaempferol and quercetin conjugates) reaching ratios of flavonol to betacyanin of 1:1.

Six anthocyanins were isolated from cell suspension cultures of an Afghan cultivar of Daucus carota by PC or HPLC. The structures of these compounds were elucidated by spectroscopic methods as cyanidin 3-O-lathyroside, cyanidin 3-O-(2''-O-beta-D-xylopyranosyl-6''-O-beta-D-glucopyranosyl-beta-D- galactopyranoside), and the latter acylated with 4-coumaric, ferulic, 4-hydroxybenzoic or sinapic acid. Unusual 1H NMR chemical shifts and 1H NOE data indicate an intramolecular copigmentation of the aglycone with these aromatic residues.

The betacyanins gomphrenin I (betanidin 6- O -β-glucoside) and its acylated forms gomphrenin II (betanidin 6- O -[6′- O -( E -4-coumaroyl)-β-glucoside]) and gomphrenin III (betanidin 6- O -[6′- O - E -feruloyl-β-glucoside]) were isolated from flowers of Gomphrena globosa and their structures elucidated by NMR spectroscopy and ion spray mass spectrometry by comparison with betanin (betanidin 5- O -β-glucoside) and its feruloyl conjugate lampranthin II (betanidin 5- O -[6′- O - E -feruloyl-β-glucoside]), which were isolated from Beta vulgaris roots and B. vulgaris cell suspension cultures, respectively. The application of this new mass spectrometric technique to this type of compound is discussed. Unusual 1 H chemical shift differences between gomphrenin I and gomphrenins II and III suggest intramolecular stacking occurring in the latter two compounds.

A major new compound was isolated from cell suspension cultures of Arabidopsis thaliana and its structure shown to be N-(E-4-coumaroyl)-aspartate by ion spray MS and MS/MS as well as 1H NMR spectroscopy. This amide was chemically synthesized and found to be identical with the natural isolate.

Ion spray mass spectrometry and tandem mass spectrometry of the fresh juice from Basella rubra fruits revealed the presence of betanidin monoglucoside as the major betacyanin and its 4-coumaroyl and feruloyl derivatives as minor components. Co-chromatography (TLC, HPLC) with betacyanin standards identified the betacyanins as gomphrenin I (15S-betanidin 6-O-β-glucoside), gomphrenin II (15S-betanidin 6-O-[6′-O-(4-coumaroyl)-β-glucoside]) together with small amounts of the respective R forms (isogomphrenin I and II) and gomphrenin III (15S-betanidin 6-O-[6′-O-feruloyl-β-glucoside]).

Two anthocyanins from the leaves of Victoria amazonica were isolated by column chromatography including preparative HPLC and have been identified by 1 H/ 13 CNMR spectroscopy and ion spray mass spectrometry as delphinidin 3- O -(2′'- O -galloyl-β- d -galactopyranoside) and cyanidin 3- O -(2′'- O -galloyl-β- d -galactopyranoside). These pigments were also found by co-chromatography in V. cruziana .