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During infection with the phanerogamic parasite Cuscuta reflexa the incompatible host plant Lycopersicon esculentum shows characteristic anatomical tissue modifications at the infection sites that are exclusively provoked following contact with Cuscuta - striking cell elongation is observed in the hypo-dermis and collenchyma of the host plant. Due to the influence of auxins on the process of cell elongation in plants, the role of indole-3-acetic acid (IAA) in the interaction of Cuscuta and Lycopersicon was studied using a highly specific enzyme-linked im-munosorbent assay for hormone measurement. It was shown that the tissue modifications in the host plant as well as cell elongation in the parasite tissue leading to the formation of an adhesive-secretory epithelium are correlated with increasing IAA levels in the respective tissues. Both anatomical modifications can also be induced artificially by injection of IAA into control tissue. Based on the obtained data, it can be hypothesized that during the parasitic attack IAA is accumulated in the haus-toria-bearing regions of Cuscuta and exuded from the epithelial cells. Due to the close contact between host and parasite, the hormone probably enters the host plant tissue causing the observed anatomical reactions.

Isoflavone patterns of Genista species from the section Spartioides in west Europe were reported. Orobol-8- C -glucoside, isoprunetin-7- O -glucoside, genistein-8- C -glucoside, genistein-6- C -glucoside, genistein-7- O -glucoside and a further, unknown isoflavone glycoside were detected in different amounts and proportions in most of the analysed Genista species. Line-scatter plots were developed to visualise the chemotaxonomic significance of the detected isoflavone glycosides. With these plots the influence of up to six characters could be demonstrated in one diagram. Line-scatter plots fill a gap between the widely used scatter plots and graphical presentations based on multivariate analysis of a large number of characters. The isoflavone patterns of the Genista specimens presented in line-scatter plots showed small intraspecific variation compared to their interspecific variation. In Genista chemotaxonomy, isoflavone patterns are useful additional characters on the species and partly on the subspecies level. This was confirmed in discriminant analysis. Together with other chemotaxonomic data (quinolizidine alkaloids), morphological, cytological, biogeographical and phytosociological characters, isoflavone patterns provided data for a species concept within the section. Further-more, the proposed subdivision of the section into the subsections Chamaespartum and Spartioides was supported by the clear differences of their isoflavone patterns. Isoflavones allowed a more detailed subdivision of the section Spartioides than alkaloid data.

Phytochemical analysis of nine species of the genus Cuscuta yielded characteristic patterns of soluble phenolic constituents that can be used as taxonomic markers. The specific patterns proved to be stable in all Cuscuta ssp. irrespective of host plant or localities.

Distribution and content of the quinolizidine alkaloids and phenylethylamine tyramine in various organs of Cytisus scoparius taken from different localities in Germany, Russia, Italy and France were analyzed by capillary GLC. Sparteine and sparteine-derivatives like 11,12- dehydrosparteine are predominant in shoots and flowers whereas lupanine-type alkaloids are mainly accumulated in seeds, pods and roots. During the year no changes within the alkaloid pattern of the young developing shoots could be observed, but the total alkaloid amount increases remarkably at the end of the vegetation period. With respect to the date of harvest only a limited variation of the alkaloid profile and content could be found in shoots, flowers and roots taken from different geographical origins. In comparison the alkaloid pattern of seeds and pods varied considerably which seemed to be correlated with the different states of maturity and not with the geographical origin. Phenylethylamine tyramine is accumulated in flowers, green pods and young developing shoots. In young developing shoots the tyramine content declined drastically during the vegetation period.

The presence of alkaloids in six species of Brongniartia and three species of Harpalyce is reported. This survey revealed remarkable qualitative differences in the alkaloid profiles of these two genera. B. discolor, B. lupinoides, B. sousae and B. intermedia showed a typical α-pyridone pattern, with cytisine, anagyrine and baptifoline as major alkaloids. In leaves of the first three species ormosanine-type alkaloids occurred additionally. B. flava and B. vazquezii are devoid of α-pyridones, but accumulate lupanine, hydroxylated lupanines and ester alkaloids. All three species of Harpalyce were similar in accumulating α-pyridones, but H. formosa differed from H. brasiliana and H. pringlei in the presence of epilupinine. In general the alkaloid profiles of Brongniartia and Harpalyce show similarities to those of the Australian genera Hovea, Lamprolobium, Plagiocarpus and Templetonia and support therefore the actual concept of the enlarged tribe Brongniartieae.

The alkaloid pattern of Templetonia incana has been investigated to provide data for comparison with other species of the genus Templetonia. The α-pyridone alkaloids cytisine, N-methylcytisine, anagyrine and some other quinolizidine alkaloids were found as major constituents in leaves, twigs, flowers and seeds of this plant. Other compounds that were identified include the bicyclic quinolizidine alkaloids lupinine and epilupinine and two hydroxysparteines. The absence of the ormosanine-type alkaloids which are typical constituents for other species of Templetonia, supports the idea that this species should be excluded from the genus Templetonia. The absence of tetrahydrocytisine derivatives in T. incana separates this species from T. biloba.

The presence of alkaloids in Templetonia biloba has been described for the first time. This species contained an unusual combination of α-pyridone alkaloids and tetra hydrocytisine derivatives with a fully saturated ring A. Cytisine, N-methylcytisine, tetra hydrorhombifoline, tetra hydrocytisine, N-methyl-tetrahydrocytisine, lupanine and 13-hydroxylupanine were found as major constituents. Other compounds that were identified include the bicyclic quinolizidine alkaloids lupinine and epilupinine. Together with the absence of ormosanine-type quinolizidines, which represent typical constituents for other species of Templetonia, these alkaloid data confirm morphological evidence that Templetonia biloba is probably misplaced in the genus Templetonia. Templetonia biloba was formerly thought to be a member of the genus Bossiaea. The alkaloid pattern of T. biloba supports its earlier removal from the genus Bossiaea, where quinolizidine alkaloids were totally missing and tyramine was found as a major compound.

As part of a detailed survey of alkaloids in the tribe Brongniartieae, the alkaloid pattern of the monotypic genus Plagiocarpus has been investigated. All extracts contained the quinolizidine alkaloids sparteine and cytisine as major compounds. Moreover β-isosparteine, 11,12-dehydrosparteine, 17-oxosparteine and anagyrine represented major alkaloids in some extracts. A group of sparteine derivatives, especially remarkable amongst them three different hydroxysparteines, and the bicyclic alkaloid lupinine contributed to the alkaloid profile as minor constituents. The co-occurrence of lupinine- and α-pyridone-type alkaloids connects this genus with the other Australian members of the Brongniartieae and confirms the monophyly of this tribe. The alkaloidal data support the idea that Plagiocarpus is more closely related to Templetonia incana, T. biloba and Lamprolobium than it is to Hovea and the remaining species of Templetonia . The presence of hydroxysparteines in both taxa could point to an especially close link of Plagiocarpus and T. incana .

A time-dependent correlation of anatomical and chemical defence reactions was shown during the incompatible reaction of tomato against the phanerogamic parasite Cuscuta reflexa. Microscopical analysis of the infection sites at the tomato stem revealed the elongation of epidermal, hypodermal and collenchymatic cells beneath the parasitic prehaustorium. After 9–11 days of infection the elongated cells had collapsed forming a visible brownish plaque at the tomato stem followed by a scalariform tissue with lignified and suberized cell walls. Concomitantly, an enhanced accumulation of soluble phenolic compounds (chlorogenic acid and an unidentified hydroxycinnamic acid derivative), as well as a stimulation of peroxidases, was observed. In contrast, PAL activity was not increased. Whereas the stimulation of phenylpropanoid metabolism could also be induced by artificial wounding, the described anatomical changes were only observed during attack of Cuscuta.

The presence of alkaloids in the genus Poecilanthe is reported for the first time. Epilupinine, 4β-hydroxyepilupinine, dihydrolusitanine, dihydroammodendrine, lusitanine, N -methylcytisine, cytisine, lupanine, N -formylcytisine, anagyrine, baptifoline, camoensidine and four novel alkaloids were found as major alkaloids in leaves and seeds of the genus Poecilanthe . Tashiromine, acetylepilupinine, ammodendrine, α-isolupanine, 5,6-dehydrolupanine, aphyllidine, aphylline, thermopsine, epibaptifoline, rhombifoline, tinctorine, 11-allylcytisine, acetylbaptifoline and at least seven unknown compounds were found as minor alkaloids in the extracts studied. The co-occurence of different types of quinolizidine (bicyclic lupinine-type, lupanine-type, leontidine-type and α-pyridone-type) and bipiperidyl alkaloids appears to be a good chemotaxonomic marker for the genus. The presence of alkaloids in Poecilanthe suggests a relationship of this genus with the tribes Sophoreae or Brongniartieae rather than with the Dalbergieae. The alkaloidal data indicate that the genus can be divided into two phytochemical groups: one group of species accumulating mainly α-pyridone alkaloids and a second group accumulating bicyclic quinolizidine alkaloids, with α-pyridones being totally absent.

Genistein-8-C-glucoside and the so far unknown genistein-6-C-glucoside have been isolated from Genista cinerea ssp cinerea. Their NMR characteristics and distribution within the section Spartioides of the genus Genista are reported.

The present work reveals new and completely different conclusions about the alkaloid economy of symbiotically fed Lupinus albus and L. albus parasitized by Cuscuta reflexa in the study period of 43-55 d after sowing of lupin. Net flows of alkaloids within lupin and between host and parasite were calculated using the molar ratio of alkaloid nitrogen:total nitrogen combined with known net flows of nitrogen in the transport fluids and analysing alkaloid accumulation in plant organs by HRGC. In contrast to previous studies, quinolizidine alkaloids were predicted to be synthesized mainly in the root of L. albus and to be predominantly transported via xylem to the apical plant shoot organs. Parasitism by C. reflexa for 12 d induced a decline of alkaloid content in the host L. albus up to 53% compared to control plants and alkaloid synthesis was halved-apparently due to a shortage of the precursor lysine. In spite of an additional decrease in nitrogen levels at the second harvest, the host-parasite system showed a 1.3-fold higher alkaloid content than the control plants, 63% of the total alkaloids being attracted by Cuscuta. This indicates (a) restriction of catabolic processes within infected lupins, (b) a massive shift of nitrogen metabolism in the direction of alkaloids and (c) an enormous sink potential of Cuscuta for nitrogenous compounds. Although xylem was found to be the main translocation system for alkaloids, the modelling of alkaloid flows predicts Cuscuta to derive only 4.5% of its total alkaloid supply from the xylem and 95.5% from the phloem. By analogy with nitrogen flows, this finding requires xylem-phloem transfers which were assumed to occur within the stem axis of lupin. A similar proportion regarding the contribution of xylem and phloem to the supply of Cuscuta was obtained for the net flows of two selected alkaloids, lupanine and 13α-tigloyloxylupanine, and for the import of total nitrogen. This result points to similar uptake mechanisms for alkaloid nitrogen and other nitrogenous compounds excluding discrimination of otherwise toxic alkaloids. Cuscuta is likely to overcome the chemical barrier of alkaloids by accumulation and catabolic processes.

Transfer of quinolizidine alkaloids from various host plants of the Fabaceae including Cytisus praecox, Chamaecytisus hirsutus, Pettena ramentacea and Spartium junceum to parasitizing Cuscuta species were studied by capillary GLC. Thirty-four quinolizidine alkaloids representing the sparteine type (e.g. sparteine, lupanine, dehydro-, oxo- and hydroxy-derivatives of sparteine and lupanine) as weil as the αpyridone type (cytisine, hydroxy-N-methylcytisine, N-formyl- and N-acetylcytisine, N-methylcytisine etc.) were detected in the host plant, whereas Cu. reflexa and Cu. platyloba were found to accumulate only 26 quinolizidine alkaloids. In all host-parasite systems studied, the major alkaloid pattern of the haustorial region of Cuscuta resembled that found in the respective legume host plant, but except for Cu. reflexa growing on Ch. hirsutus differences could be observed as to quantitafive composition. Cuscuta reflexa and Cu. platyloba infesting Cy. praecox accumutated preferentially lupanine, whereas both Cuscuta species lacked the alkaloids α-isosparteine and 17-oxosparteine which were also abseht in the phloem exudate of Cy. praecox. Anagyrine was discriminated both in Cu. reflexa parasitizing on Pe. ramentaceae and in Cu. platyloba infesting Sp. junceum. Similar alkaloid patterns were obtained for Cu. reflexa and Cu. platyloba growing on Cy. praecox indicating that alkaloid uptake and transport within the parasite are independent of the respective Cuscuta species.

Summary Lipophilous carotenoids together with chlorophyll a were extracted in acetone from 1) a variety of cyanobacterial lichens stemming from habitats with strongly different light exposure, ranging from the Judean Desert, Israel, to a shaded forest floor in Germany, 2) Peltigera praetextata collected from a deciduous forest in the vicinity of Wurzburg at bimonthly intervals during an entire year, 3) Peltigera species which in a short term experiment (five days) had been exposed to altered light conditions with respect to those they had grown under. Pigment determination by high performance liquid chromatography (HPLC) showed no clear trend in the concentrations of zeaxanthin (and echinenone) under different incident light intensities. In contrast, canthaxanthin contents increased and the concentrations of chlorophyll a and β-carotene decreased with enhanced light exposure of the lichens. This was observed for all three types of investigation and indicates that the ratio of canthaxanthin to β-carotene in a cyanobacterial lichen is strongly influenced by the light environment it has recently grown in.

A recently developed empirically based modelling technique was used to quantify uptake, flow and utilization of C and N in Lupinus albus L., uninfected and parasitized by Cuscuta reflexa Roxb. plants over a 12 d period during flowering and early fruit setting of the host. The modelling combined data on molar C:N ratios in host phloem and pressure-induced xylem sap, net increments of C and N in host and parasite plant parts and respiratory losses of C. The modelling of the solute transfer between host and Cuscuta was achieved by assuming non-specific intake from the xylem. The models predicted that Cuscuta derived 99.5% of its carbon and 93.6% of its nitrogen demand from the host phloem

Two ester alkaloids, cineverine and a new compound, for which we suggest the name cineroctine, were isolated from twigs of Genista cinerea subsp. cinerea . Their structures were determined by spectroscopic methods to be 13α-(3′, 4′-dimethoxybenzoyl)oxylupanine (cineverine) and 13α-(3-hydroxy- cis -oct-5-enoyl)oxylupanine (cineroctine), 13- O -axial derivatives of lupanine. The distribution of these ester alkaloids amongst the different species of the section Spartioides of the genus Genista is recorded.

The alkaloid pattern from various organs of Leontice leontopetalum L. and L. ewersmannii Bge. (Berberidaceae) was analyzed by capillary GC and GC-MS. For L. leontopetalum 19 quinolizidine alkaloids could be detected; 15 compounds are new for this species. The alkaloid pattern of L. leontopetalum is characterized by quinolizidine alkaloids of the lupanine-type with lupanine as main compound. In L. ewersmannii 15 quinolizidine alkaloids could be found; nine constituents are described for this species for the first time. In contrast to L. leontopetalum, L. ewersmannii accumulates quinolizidine alkaloids of the matrine-type and the α-pyridone-type as major compounds. The taxonomic meaning of alkaloid profiles in Leontice and Leonticeae is discussed.

Cuscuta reflexa, Lupinus angustifolius, Quinolizidine Alkaloids, Parasitism During parasitism on Lupinus angustifolius the phanerogamic parasite Cuscuta reflexa takes up quinolizidine alkaloids from L. angustifolius via haustoria that tap xylem and phloem ves­sels of the host. The alkaloid pattern of the haustorial region of C. reflexa as revealed by GLC as well as by GLC-M S closely resembles that of infested lupin stems. With increasing distance from the haustoria towards the apex of C. reflexa the complex alkaloid pattern of the host is significantly reduced. Whereas alkaloid esters such as 13-benzoyloxylupanine and 13-cinnamoyloxy-lupanine are prominent peaks in the alkaloid profiles of the host as well as of the haustorial region of the parasite they are not detected in the apex of C. reflexa but are replaced by their respective alcohol com ponent 13-hydroxylupanine. This change of alkaloid profiles is accompanied by a strong decline of alkaloid concentration which drops from ap­ proximately 11 m g/g dry wt. in the haustorial region of C. reflexa to 0.2 m g/g dry wt. in the apex. Alkaloid analyses of xylem sap and phloem exudate from L. angustifolius suggest that uptake of host plant alkaloids by C. reflexa is mainly via the phloem even though a contribu­tion of xylem sap to the supply of alkaloids to the parasite can not be excluded.

The alkaloids of Lamprolobium fruticosum and L. grandiflorum have been studied to provide data for comparisons with other genera of the tribe Brongniartieae. Both species contained the quinolizidine alkaloids cytisine, N -methylcytisine, anagyrine and epibaptifoline as major compounds. L. fruticosum differs from L. grandiflorum in accumulating quite high amounts of bicyclic lupinine-type alkaloids and lamprolobine thus indicating the chemotaxonomic value of alkaloids at the subgeneric level. The distribution of lamprolobine, however, varied greatly among different samples of L. fruticosum . The co-occurrence of lupinine-type and α-pyridone-type alkaloids distinguishes this genus from Hovea and Templetonia and suggests an affinity with the South American genus Harpalyce .

A new styrylpyrone was isolated from vegetative gametophytes of Equisetum arvense. Its structure was determined spectroscopically to be 3,4-dihydro

Twenty-five quinolizidine alkaloids, and the dipiperidyl alkaloid, ammodendrine, have been found in Petteria ramentacea. Nineteen alkaloids are described for the first time in this plant. Cytisine-12-carboxy-methylester represented a new quinolizidine alkaloid. The distribution of alkaloids in buds, leaves, flowers, ripe pods, unripe fruits, seeds, stem bark, stem wood and roots was investigated. The alkaloid content and alkaloid profile changed strongly during the vegetation period.

A study of the alkaloids from Hesperolaburnum platycarpum has shown the presence of several quinolizidine and bipiperidyl alkaloids, including the quinolizidine alkaloids α-isosparteine, sparteine, lupanine, 3β-hydroxylupaline, 7-hydroxylupanine and unknown 1 as major compounts. Three bipiperidyl alkaloids, ammodendrine and two isomers of adenocarpine, were present in small amounts. The co-occurrence of quinolizidine alkaloids and adenocarpine is a good chemotaxonomic character for the monotypic genus Hesperolaburnum and suggests a close affinity of this genus to Cytisophyllum .

Alkaloid extracts from different organs of Adenocarpus hispanicus ssp. hispanicus and Adenocarpus hispanicus ssp. gredensis were analyzed by capillary GC. Twenty-four compounds could be identified by the high sensitive method of GLC-MS: the pyrrolizidine alkaloids decorticasine, N-acetylnorloline and N-butyrylnorloline, the bipiperidyl alkaloid ammodendrine, the phenylethylamine tyramine and 19 quinolizidine alkaloids. In contrast to Adenocarpus complicatus, Adenocarpus foliolosus and Adenocarpus viscosus the alkaloid pattern of Adenocarpus hispanicus is characterized by the occurrence of quinolizidine alkaloids with sparteine predominating in the leaves and numerous dehydroderivatives of sparteine. Remarkable is the total absence of adenocarpine which was described as a main compound of the three former species. Our results strongly support the opinion that the genus Adenocarpus should be divided into two phytochemical groups. © 1992, Walter de Gruyter. All rights reserved.

The alkaloid pattern of the Genista cinerea agregat was investigated by GC and GC-MS. At least 15 alkaloids were found in G. cinerascens , 20 alkaloids in G. majorica and 16 alkaloids in G. cinerea ssp. ausetana . Twigs of G. cinerascens contained the α-pyridone alkaloids cytisine and anagyrine as main compounds, whereas lupanine, 13-hydroxylupanine and the ester alkaloids 13-tigloyloxylupanine and 13-benzoyloxylupanine were found as predominant constituents in twigs of G. majorica and the different subspecies of G. cinerea . Investigations of seeds, pods, fruits and flowers confirmed the alkaloid pattern found in twigs. The alkaloid data give no support for a close affinity between G. cinerascens and the other two species of the agregat, G. majorica and G. cinerea .

The alkaloid composition of seeds from 10 different species and subspecies of the genus Adenocarpus was analysed by capillary GC and GC-MS. At least nine alkaloids couldbe identified. Four compounds have not been formerly reported for the genus Adenocarpus. Significant differences were found in the alkaloid pattern of flowers, seeds, leaves and twigs. Seeds accumulate simple pyrrolizidine alkaloids as major compounds, whereas leaves and twigs contain the bipiperidyl alkaloids cis- and rans- adenocarpine as predominant constituents. Flowers store high amounts of tyramine. The alkaloidal data support the idea of an affinity Adenocarpus with Laburnum and Cytisophyllum.

Summary The alkaloid pattern of the graft hybrid Laburnocytisus adamii (Laburnum anagyroides + Cytisus purpureus) was analysed by GC and GC-MS. 14 alkaloids (mostly quinolizidine alkaloids, but also bipiperidyl and pyrrolizidine alkaloids) were identified. Interesting seasonal changes of the alkaloid pattern were observed in leaves. Leaf buds accumulate the highest total alkaloid amount with more than 90 % cytisine. During the development of the leaves in spring, a substantial increase of N-methylcytisine was observed. Later in the year, the alkaloid concentration of the leaves strongly declined. The alkaloid pattern did not reflect the hybrid status of Laburnocytisus adamii . It was very close to that of Laburnum anagyroides , while the typical alkaloids of Cytisus purpureus could not be detected. However, remarkable quantitative differences were observed. The alkaloid content of plant parts originating from Laburnum were as high as in Laburnum anagyroides , whereas those originating from Cytisus were rather low. Thus the hybrid status of this plant is both reflected in its morphology and its content of quinolizidine alkaloids.

orty-three quinolizidine alkaloids, and the dipiperidyl alkaloid, ammodendrine, have been found in Virgilia divaricata and V. oroboides . Three new quinolizidine alkaloids were detected, viz. virgilidone, 4β- O -(2′-pyrrolylcarboxyl)- epilupinine and 4β-hydroxy-1 1- O -(2′-pyrrolylcarboxyl)-epilupinine. The distribution of alkaloids in air-dried leaves, flowers, pods, seeds and twigs of the two species was also investigated. The unique combination of bi-, tri- and tetracyclic quinolizidine alkaloids is typical of the genus Virgilia .

The alkaloid pattern of Spartium junceum has been investigated. Cytisine, N-methylcytisine, anagyrine, rhombifoline and epi-baptifoline occur as major compounds in most of the samples studied. Considerable quantitative differences were found between various parts of the plant. The alkaloid content changed strongly dependent on the seasons. Only a limited variation can be ascribed to geographical origin.

Summary The alkaloid composition of the overground parts (leaves, petioles, stems, flowers, fruits and seeds) of Laburnum watereri (hybrid of Laburnum alpinum × L. anagyroides ) and its seasonal changes (from march to november) have been studied by different chromatographic (TLC, capillary GC) and spectroscopic (GC/MS, HRMS, 1 H-NMR, 13 C-NMR, IR, UV) methods. Seeds only contain cytisine. Besides cytisine, traces of methylcytisine and ammodendrine 12 further alkaloids could be identified in the fruits, among which β-isosparteine, 14e-hydroxysparteine and epi-baptifoline have been found for the first time in the genus Laburnum . Following the seasonal changes of the alkaloid composition of the fruits, an increase of epibaptifoline and ammodendrine was established during ripening, while the content of the main compound cytisine strongly declined. The highest total amount of alkaloids (with 80 to 90% cytisine) was found in the buds in the spring. During the further development of the leaves, the cystine content decreases and a methylation of this alkaloid begins. In summer the alkaloid concentration reaches the lowest level. In the course of July epi-baptifoline (erroneously reported as methylcytisine in literature) increases and becomes the main alkaloid for the following 6 months.

Kaempferol-3-O-rutinoside-7-O-sophoroside and kaempferol-3-O-(6-O-malonylgluco-side)-7-O-glucoside were isolated from Equisetum palustre and Equisetum x litorale, respectively. Their structures are prooved

Twenty-nine quinolizidine alkaloids have been found and characterized from the combined leaf/hypocotyl extracts of Lupinus polyphyllus. Twelve have not been found previously in this plant and the structure of 10 has been unambiguously assigned from a combination of mass spectroscopy and NMR data, and by direct comparison with synthetic material for the N-carboxymethyl ester, N-carboxyethyl ester and N-formyl derivatives of angustifoline. The co-occurrence of 13α-hydroxylupanine and its 13β-isomer is reported for the first time in a quinolizidine alkaloid-accumulating species.

5-Caffeoylshikimic acid was isolated from the methanolic extract of the barren sprouts of Equisetum arvense . The structure was elucidated spectroscopically. The distribution of this depside and some other phenylpropanoic acid derivatives within the Equisetaceae and some ferns are reported.

Quinolizidine alkaloids were surveyed in 22 plant samples, representing nineOrmosia species and up to five different plant parts per species, using combined gas chromatography and mass spectroscopy. The detected alkaloids were classified into 40 structural types. There was a remarkable degree of dissimilarity of alkaloid-type profiles between any two plant samples, including those obtained from the same species and even from a single tree. The similarity of alkaloid-type profiles among the studied samples varied between 0% and 79% (Jaccard similarity coefficient). Of chemotaxonomic interest was the finding of acosmine inO. isthmensis, which previously had been reported only from the related genusAcosmium. Furthermore, the alkaloid-type profile ofO. panamensis seeds was distinct from that of all other samples, supporting the hypothesis that this species is only distantly related to the other Latin AmericanOrmosia species.

Quinolizidine alkaloids were surveyed using gas chromatography (GC) and combined mass spectroscopy (MS) in bark or leaves of eleven species ofOrmosia Jackson as well as inClathrotropis macrocarpa Ducke from tropical forests in Latin America. A list of detected alkaloids, with their MS fragmentation patterns and GC retention indices, is given, as are the distribution of alkaloids among the samples and their detected concentrations. Alkaloid diversity inOrmosia was high, and the taxonomic distribution of specific alkaloids was not congruent with morphological taxonomic criteria: Of 143 alkaloids apparent in 14 samples, 65 were observed in only one sample, and no single alkaloid was common to all samples. Within a species, alkaloid concentrations were inconsistent and therefore cannot be used as a taxonomic character. This was shown for leaf alkaloid concentrations of two neighboring conspecific trees in the same habitat.

Summary Intact plants of Catharanthus roseus have been differentiated from haploid and diploid calluses. These regenerations have been initiated by cultivating the tissues 13 months (diploid cells), respectively 5 months (haploid cells) with different combinations concerning the concentrations of phytohormones (kinetin and β-indolyl-acetic acid). Since four years we have grown the induced plants in the greenhouse and have propagated them by shoots and seeds. Phytochemical investigations have shown that the regenerated plants may contain twice as much serpentine/raubasine as the stock plants and several times as much of these alkaloids as the calluses the regenerates came from. The importance of tissue cultures for production of high-yielding strains of medicinal plants has been stressed especially.

Summary 2 alkaloid free Cuscuta species ( C. reflexa and C. patyloba ) have been cultivated under definite conditions with different alkaloid containing host plants (species of the genera Atropa , Berberis , Datura , Duboisia , Lupinus , Nicotiana ). The parasites take up the specific alkaloids of the host plant by its haustoria mainly via phloem and xylem. The concentration of alkaloids in Cuscuta is sometimes lower, but often higher as in the host plant. This “ Cuscuta -host plant-system” has been established for further studies about the mechanism of alkaloid accumulation and to look after a system of depoisening these cytotoxic compounds by bringing them into the vacuole (via a carrier?).

The relationship between the carotenoid zeaxanthin, formed by violaxanthin de-epoxidation, and nonphotochemical fluorescence quenching (qNP) in the light was investigated in leaves of Glycine max during a transient from dark to light in 2% O2, 0% CO2 at 100 to 200 micromoles of photons per square meter per second. (a) Up to a qNP (which can vary between 0 and 1) of about 0.7, the zeaxanthin content of leaves was linearly correlated with qNP as well as with the rate constant for radiationless energy dissipation in the antenna chlorophyll (kD). Beyond this point, at very high degrees of fluorescence quenching, only kD was directly proportional to the zeaxanthin content. (b) The relationship between zeaxanthin and kD was quantitatively similar for the rapidly relaxing quenching induced in 2% O2, 0% CO2 at 200 micromoles of photons per square meter per second and for the sustained quenching induced by long-term exposure of Nerium oleander to drought in high light (B Demmig, K Winter, A Kruger, F-C Czygan [1988] Plant Physiol 87: 17-24). These findings suggest that the same dissipation process may be induced by very different treatments and that this particular dissipation process can have widely different relaxation kinetics. (c) A rapid induction of strong nonphotochemical fluorescence quenching within about 1 minute was observed exclusively in leaves which already contained a background level of zeaxanthin.

The pigmentation of 23 species of Neospongiococcum Deason was studied in the stationary phase of nitrogen-limited cultures on agar with or without glucose or in liquid medium. Fourteen species gradually developed an orange or brown color, and in all, secondary carotenoids were detected by thin-layer chromatography. Among these, the keto-carotenoids echinenone, canthaxanthin and esterified astaxanthin were identified, although the last named was not always present. When aging on glucose agar, the remaining nine species developed only a yellow-green or yellow color and a pronounced tendency to bleach. In these, the aforementioned keto-carotenoids were lacking, and β-carotene and lutein lucre dominant. From this study it is not clear whether secondary carotenoid formation is species-specific in Neospongiococcum.

Intact attached sun leaves of Helianthus annuus and shade leaves of Monstera deliciosa and Hedera helix were used to obtain light response curves of CO(2) uptake, the content of the carotenoid zeaxanthin (formed by violaxanthin de-epoxidation), as well as nonphotochemical quenching (q(NP)), and the rate constant of radiationless energy dissipation (k(D)). The latter two parameters were calculated from the decrease of chlorophyll a fluorescence at closed photosystem II traps in saturating pulses in the light. Among the three species, the light-saturated capacity of CO(2) uptake differed widely and light saturation of CO(2) uptake occurred at very different photon flux densities. Fluorescence quenching and zeaxanthin content exhibited features which were common to all three species: below light-saturation of CO(2) uptake nonphotochemical quenching occurred in the absence of zeaxanthin and was not accompanied by a decrease in the yield of instantaneous fluorescence. Nonphotochemical quenching, q(NP), increased up to values which ranged between 0.35 and 0.5 when based on a control value of the yield of variable fluorescence determined after 12 hours of darkness. As light saturation of CO(2) uptake was approached, q(NP) showed a secondary increase and the zeaxanthin content of the leaves began to rise. This was also the point from which the yield of instantaneous fluorescence began to decrease. The increase in zeaxanthin was paralleled by an increase in the rate constant for radiationless energy dissipation k(D), which opens the possibility that zeaxanthin is related to the rapidly relaxing "high-energy-state quenching" in leaves.

Composition and metabolism of carotenoids in Arctodiaptomus bacillifer taken from a mountain lake in the Alps have been studied. This copepode contains esters of astaxanthin (3,3′-dihydroxy-β,β-carotene-4,4′-dion) mainly. Besides β-carotene (β,β-carotene) and unesterified zeaxanthin (β,β-carotene-3,3′-diol), esters of hydroxyechinenone (3-hydroxy-β,β-caroten-4-one), adonixanthin (3,3′-dihydroxy-β,β-caroten-4-one), and zeaxanthin were found. The metabolism of carotenoids in Arctodiaptomus bacillifer and a possible way of astaxanthin biosynthesis have been discussed.