Phytochemistry (v.57, #5)
Global phytochemistry: the Brazilian approach by Massuo Jorge Kato (621-623).
Primary sequence determination of a Kunitz inhibitor isolated from Delonix regia seeds by Silvana C Pando; Maria L.V Oliva; Claudio A.M Sampaio; Luciana Di Ciero; José C Novello; Sérgio Marangoni (625-631).
A serine proteinase inhibitor was purified from Delonix regia seeds a Leguminosae tree of the Caesalpinioideae subfamily. The inhibitor named DrTI, inactivated trypsin and human plasma kallikrein with K i values 2.19×10−8 M and 5.25 nM, respectively. Its analysis by SDS-PAGE 10–20% showed that the inhibitor is a protein with a single polypeptide chain of M r 22 h Da. The primary sequence of the inhibitor was determined by Edman degradation, thus indicating that it contained 185 amino acids and showed that it belongs to the Kunitz type family; however, its reactive site did not contain Arg or Lys at the putative reactive site (position 63, SbTI numbering) or it was displaced when compared to other Kunitz-type inhibitors.A Kunitz inhibitor was obtained for Delonix regia seeds which inactivated trypsin and human kallikrein. Its reactive catalytic site did not contain Arg or Lys at position 63, SbTi numbering, in contrast to other known inhibitors.
Keywords: Delonix regia; Leguminosae; Kunitz inhibitor; Serine proteinase; Trypsin; Human plasma kallikrein;
Vanadium haloperoxidases from brown algae of the Laminariaceae family by M. Almeida; S. Filipe; M. Humanes; M.F. Maia; R. Melo; N. Severino; J.A.L. da Silva; J.J.R. Fraústo da Silva; R. Wever (633-642).
Vanadium haloperoxidases were extracted, purified and characterized from three different species of Laminariaceae — Laminaria saccharina (Linné) Lamouroux, Laminaria hyperborea (Gunner) Foslie and Laminaria ochroleuca de la Pylaie. Two different forms of the vanadium haloperoxidases were purified from L. saccharina and L. hyperborea and one form from L. ochroleuca species. Reconstitution experiments in the presence of several metal ions showed that only vanadium(V) completely restored the enzymes activity. The stability of some enzymes in mixtures of buffer solution and several organic solvents such as acetone, ethanol, methanol and 1-propanol was noteworthy; for instance, after 30 days at least 40% of the initial activity for some isoforms remained in mixtures of 3:1 buffer solution/organic solvent. The enzymes were also moderately thermostable, keeping full activity up to 40°C. Some preliminary steady-state kinetic studies were performed and apparent Michaelis–Menten kinetic parameters were determined for the substrates iodide and hydrogen peroxide. Histochemical studies were also performed in fresh tissue sections from stipe and blade of L. hyperborea and L. saccharina, showing that haloperoxidase activity was concentrated in the external cortex near the cuticle, although some activity was also observed in the inner cortical region.Vanadium bromoperoxidases were purified and characterized from three different species of brown algae: Laminaria saccharina, Laminaria hyperborea and Laminaria ochroleuca. For L. saccharina and L. hyperborea it was possible to isolate two forms of the enzyme whereas for L. ochroleuca only one form was isolated.
Keywords: Laminaria saccharina; Laminaria hyperborea; Laminaria ochroleuca; Laminariaceae; Vanadium in biology; Vanadium-dependent haloperoxidases;
Endoplasmic oleoyl-PC desaturase references the second double bond by Jennifer L Schwartzbeck; Sook Jung; Albert G Abbott; Erin Mosley; Shahed Lewis; Gina L Pries; Gary L Powell (643-652).
This enzyme from higher plants catalyzes the first step in polyunsaturated fatty acid biosynthesis. It is neither an ω-6 nor a Δ12 desaturase but primarily references the monoenoic double bond. Nonadecenoic acid is desaturated to 10(Z)13(Z)C19:2.
Keywords: Arachis hypogaea L.; Fabaceae; Peanut; Groundnut; Regiospecificity; Oleoyl-PC desaturase; Omega-6 desaturase; Delta-12 desaturase; Fatty acids; Polyunsaturated;
Main glucosidase conversion products of the gluco-alkaloids dolichantoside and palicoside by Viviane Brandt; Monique Tits; Jacques Penelle; Michel Frédérich; Luc Angenot (653-659).
The enzymatic glucose cleavage of palicoside revealed the biosynthetic pathway to akagerine, whereas the conversion of dolichantoside led to a new quaternary heteroyohimbine alkaloid named N b-methyl-21-β-hydroxy-mayumbine. The hypothetical models of reactions occurring after the conversion of both substrates are proposed. Dolichantoside and palicoside, as well as Strychnos mellodora stem bark crude ethanol extract, exhibit significant antimycotic activity against human pathogens in presence of specific glucosidase.The enzymatic glucose cleavage of palicoside (2) revealed the biosynthetic pathway to akagerine (5), whereas the conversion of dolichantoside (1) led to a quaternary alkaloid named N b-methyl-21-β-hydroxy-mayumbine (4). The hypothetical models of reactions occurring after the conversion of both substrates are proposed.
Keywords: Strychnos mellodora; Loganiaceae; Biosynthesis; Gluco-alkaloids; Dolichantoside; Palicoside; Akagerine; N b-Methyl-21-β-hydroxy-mayumbine;
Structure of fructans from excised leaves of New Zealand flax by Ian M Sims; Andrew J Cairns; Richard H Furneaux (661-668).
The accumulation of total water-soluble carbohydrate, and specifically sucrose and fructan, by excised leaves of Phormium tenax and P. cookianum (family Phormiaceae J. G. Agardh, order Asparagales) was investigated. Total water-soluble carbohydrate content of excised leaves of P. tenax and P. cookianum increased during 48 h of continuous illumination at an average rate of 1.3 and 0.9 mg g−1 fresh weight leaf per hour, respectively. The sucrose content of excised leaves increased throughout the experimental period. The fructan content of excised leaves of P. tenax increased slightly throughout the experimental period, whilst that of P. cookianum was variable and showed no overall change. Chemical and spectroscopic analysis of the fructans obtained from the two Phormium species showed that they were similar to each other and contained mostly 1-linked and terminal fructofuranosyl (Fruf) residues, together with smaller amounts of 6-linked Fruf, 1,6-branched Fruf, terminal and 6-linked glucopyranosyl residues. Separation of the fructans by thin-layer and high-performance anion-exchange chromatography revealed the presence of a complex mixture of fructo-oligosaccharides and higher molecular weight fructan. The branched structure of the fructans isolated from excised leaves of Phormium resembles that of fructans and fructo-oligosaccharides isolated from some related species within the order Asparagales (Agave vera cruz, Cordyline australis and Urginea maritima), but is distinct from the linear structure of fructans from others (Allium cepa and Asparagus officinalis). The structural heterogeniety of fructans within both the order Asparagales and superorder Liliiflorae may be a useful chemotaxonomic aid.The accumulation of water-soluble carbohydrates, and specifically sucrose and fructans, by exised and illuminated leaves of Phormium tenax and P. cookianum was investigated. Fructans have been isolated from the water-soluble carbohydrate extracts and their composition and structure determined by a range of chromatographic and spectrometric techniques.
Keywords: Phormium tenax; Phormium cookianum; Phormiaceae; New Zealand flax; Water-soluble carbohydrate; Fructan; Accumulation; Structure;
Biotransformation of (+)- and (−)-camphorquinones by plant cultured cells by Wen Chai; Hiroki Hamada; Jumpei Suhara; C. Akira Horiuchi (669-673).
Biotransformation of (+)- and (−)-camphorquinones with suspension plant cultured cells of Nicotiana tabacum and Catharanthus roseus was investigated. It was found that the plant cultured cells of N. tabacum and C. roseus reduce stereoselectively the carbonyl group of (+)- and (−)-camphorquinones to the corresponding α-keto alcohols.Biotransformation of (+)- and (−)-camphorquinone with suspension plant cultured cells Nicotiana tabacum and Catharanthus roseus yielded the corresponding α-keto alcohols.
Keywords: Nicotiana tabacum; Solanaceae; Catharanthus roseus; Apocynaceae reduction; Biotransformation; (+)-Camphorquinone; (−)-Camphorquinone; 2-exo-Hydroxyepicamphor; 2-endo-Hydroxyepicamphor; 3-exo-Hydroxycamphor; 3-endo-Hydroxycamphor;
Biotransformation of geranyl acetate to geraniol during palmarosa (Cymbopogon martinii, Roxb. wats. var. motia) inflorescence development by Vinod Shanker Dubey; Rajesh Luthra (675-680).
Only immature palmarosa (Cymbopogon martinii, Roxb. wats. var. motia) inflorescence with unopened spikelets accumulated essential oil substantially. Geraniol and geranyl acetate together constituted about 90% of the palmarosa oil. The proportion of geranyl acetate in the oil decreased significantly with a corresponding increase of geraniol, during inflorescence development. An esterase enzyme activity, involved in the transformation of geranyl acetate to geraniol, was detected from the immature inflorescence using a gas chromatographic procedure. The enzyme, termed as geranyl acetate cleaving esterase (GAE), was found to be active in the alkaline pH range with the optimum at pH 8.5. The catalysis of geranyl acetate was linear up to 6 h, and after 24 h of incubation, 75% of the geranyl acetate incubated was hydrolyzed. The GAE enzymic preparation, when stored at 4°C for a week, was quite stable with only 40% loss of activity. The physiological role of GAE in the production of geraniol during palmarosa inflorescence development has been discussed.An esterase enzyme activity involved in the transformation of acyclic monoterpenyl acetate-geranyl acetate to geraniol, referred to as geranyl acetate esterase (GAE), has been demonstrated for the first time from palmarosa inflorescence.
Keywords: Palmarosa; Cymbopogon; Essential oil; Geraniol; Geranyl acetate; Esterase; Biotransformation;
Seasonal variation of monoterpene emission from Malus domestica and Prunus avium by Francesca Rapparini; Rita Baraldi; Osvaldo Facini (681-687).
Emission rates of monoterpenes released by apple (Malus domestica Borkh) and cherry (Prunus avium L.) were estimated at different phenological stages. These measurements employed a dynamic flow-through Teflon chamber, sample collection onto cartridges filled with graphitized carbon and thermal desorption gas chromatography–mass spectrometry (GC–MS) for identification and quantification of the emitted volatiles. At full bloom the release of monoterpene hydrocarbons from cherry flowers was 1213 ng g−1 dry weight (DW) h−1, exceeding by approximately three-fold the emission rate of apple flowers (366 ng g−1 DW h−1). Observed seasonal variations in biogenic volatile organic compound (VOC) emissions ranged over several order of magnitudes. At fruit-set and ripening stages, in fact, the hydrocarbon emission dramatically decreased reaching the lowest values at harvest time when leaves were fully mature (3–9 ng g−1 DW h−1). Wide diversity in the composition of compounds from the species studied was also recorded. At blooming, linalool contributed significantly to the monoterpene emission from apple (94% of the emitted carbon) while α-pinene and camphene represented on average more than 60% of the total emitted volatiles from cherry flowers. Among the monoterpenes identified in flowers, α-pinene, camphene and limonene were also found in the foliage emission of both species. Fruit trees are relevant monoterpene emitters only at blooming and thus for a short period of the vegetative cycle. When leaves are fully developed, the carbon loss due to monoterpene emissions related to the photosynthetically carbon gain is negligible.Monoterpene emissions from apple and cherry were estimated at different phenological stages. Cherry was a high monoterpene emitter only at full bloom.
Keywords: Malus domestica; Prunus avium; Rosaceae; Apple; Cherry; Emission; Monoterpenes; Flowers; Leaves; Seasonality;
Botrydial is produced in plant tissues infected by Botrytis cinerea by Nigel Deighton; Ingo Muckenschnabel; Ana J Colmenares; Isidro G Collado; Brian Williamson (689-692).
The fungal metabolite botrydial was detected for the first time in ripe fruits of sweet pepper (Capsicum annuum) wound-inoculated with conidial suspensions of Botrytis cinerea and also in leaves of Phaseolus vulgaris and Arabidopsis thaliana inoculated without wounding. This phytotoxin was produced in soft rot regions of the infection. In C. annuum, the most aggressive isolate produced the highest botrydial concentrations in planta. The levels of botrydial produced by this isolate did not correlate with the reported relative susceptibilities of four P. vulgaris genotypes. The results suggest that botrydial is a pathogenicity factor for this fungus, but not a primary determinant of pathogenicity.The sesquiterpene botrydial has been found in fruits of Capsicum annuum and leaves of Phaseolus vulgaris and Arabidopsis thaliana inoculated with conidial suspensions of Botrytis cinerea.
Keywords: Botrytis cinerea; Fungal metabolites; Phytotoxicity; Capsicum annuum; Phaseolus vulgaris; Arabidopsis thaliana;
Identification of glucosinolates on the leaf surface of plants from the Cruciferae and other closely related species by D.Wynne Griffiths; Nigel Deighton; A.Nicholas E Birch; Bruno Patrian; Robert Baur; Erich Städler (693-700).
Leaf-surface extracts prepared from 18 non-cultivated (wild) plant species, derived from the Capparidaceae, Cruciferae, Resedaceae and Tropaeolaceae were ranked for their ability to stimulate oviposition by the cabbage root fly, and analysed for glucosinolates. A total of 28 different glucosinolates were identified. A clear relationship was detected between the indolyl-, benzyl- and the total glucosinolate composition on the leaf surface and oviposition preference by cabbage root fly females. However, as the results are not fully explained by differences in leaf surface glucosinolates, other important oviposition deterrents and stimuli on the leaf surface of these wild crucifers must also be present.A total of 28 glucosinolates have been identified in leaf surface extracts from 18 plant species derived from the Capparidaceae, Cruciferae, Resedaceae and Tropaeolaceae. Results are discussed in relation to the ability of the plants to stimulate oviposition by the cabbage root fly (Delia radicum).
Keywords: Leaf surface glucosinolates; Capparidaceae; Cruciferae; Resedaceae; Tropaeolaceae; Cabbage root fly; Delia radicum;
Antioxidant enzymes responses to cadmium in radish tissues by Angela P Vitória; Peter J Lea; Ricardo A Azevedo (701-710).
To investigate the antioxidant responses of radish (Raphanus sativus L.) to cadmium (Cd) treatment, seedlings of a tolerant variety were grown in increasing concentrations of CdCl2, ranging from 0.25–1 mM, for up to 72 h in a hydroponic system. Analysis of Cd uptake indicated that most of the Cd accumulated in the roots, but some was also translocated and accumulated in the leaves, especially at the higher concentrations of Cd used in the experiments. Roots and leaves were analysed for catalase, glutathione reductase and superoxide dismutase activities. Catalase and glutathione reductase activities increased considerably in the roots and leaves after 24 h exposure to the metal, indicating a direct correlation with Cd accumulation. The analysis of native PAGE enzyme activity staining, revealed several superoxide dismutase isoenzymes in leaves, with the two predominant isoenzymes exhibiting increases in activity in response to Cd treatment. The results suggest that in radish, the activity of antioxidant enzymes responds to Cd treatment. The main response may be via the activation of the ascorbate–glutathione cycle for the removal of hydrogen peroxide, or to ensure the availability of glutathione for the synthesis of Cd-binding proteins.Cd accumulation in radish roots exposed to (•) 0 mM, (○) 0.5 mM and (■) 1 mM CdCl2 is shown.
Keywords: Raphanus sativus; Radish; Antioxidant enzymes; Cadmium; Catalase; Glutathione reductase; Phytochelatins; Superoxide dismutase;
3-O-Methyl-d-galactose residues in lycophyte primary cell walls by Zoë A Popper; Ian H Sadler; Stephen C Fry (711-719).
Acid hydrolysis of cell wall-rich material from young leaves of the lycophyte Selaginella apoda (L.) Spring yielded substantial amounts of 3-O-methyl-d-galactose (1) in addition to the usual major monosaccharides (glucose, galactose, arabinose, xylose and galacturonic acid). The yield of 1 approximately equalled that of galacturonic acid. Compound 1 was identified as 3-O-methylgalactose by its 1H and 13C NMR spectra, and shown to be the d-enantiomer by its susceptibility to d-galactose oxidase. Compound 1 was detected in acid hydrolysates of the alcohol-insoluble residues from young leaves of all lycophytes tested, both homosporous (Lycopodium, Huperzia and Diphasiastrum) and heterosporous (Selaginella). It was not detectable in the charophyte green algae Coleochaete scutata, Chara coralina or Klebsormidium flaccidum, any bryophytes [a hornwort (Anthoceros), four liverworts and three mosses], or any euphyllophytes [a psilopsid (Psilotum), a horsetail (Equisetum), eusporangiate and leptosporangiate ferns, the gymnosperm Gnetum, and diverse angiosperms]. A high content of 1 is thus an autapomorphy of the lycophytes.Acid hydrolysis of primary cell walls of all the lycophytes tested (Selaginella, Lycopodium, Huperzia and Diphasiastrum) yielded substantial amounts of 3-O-methyl-d-galactose (1). Compound 1 was undetectable in hydrolysates of cell walls from euphyllophytes (non-lycophyte vascular plants), bryophytes and charophycean algae. A high proportion of 1 is thus an autapomorphy of the lycophytes.
Keywords: Selaginella apoda; S. erythropus; Lycopodium pinifolium; Huperzia selago; Diphasiastrum alpinum; Lycophytes; Euphyllophytes; Pteridophytes; Primary cell walls; Polysaccharides; 3-O-Methyl-d-galactose; NMR spectroscopy; HMBC; HMQC;
Dihydroxynortropane alkaloids from calystegine-producing plants by Naoki Asano; Kae Yokoyama; Mio Sakurai; Kyoko Ikeda; Haruhisa Kizu; Atsushi Kato; Munehisa Arisawa; Dirk Höke; Birgit Dräger; Alison A Watson; Robert J Nash (721-726).
Three dihydroxynortropanes, 2α,7β-dihydroxynortropane, 2α,3β-dihydroxynortropane, and 3α,7β-dihydroxynortropane, were isolated from calystegine-producing plants in the families Convolvulaceae and Solanaceae. 2α,7β-Dihydroxynortropane was isolated from six species in the Convolvulaceae whereas only Calystegia soldanella contained it and 2α,3β-dihydroxynortropane. Although neither of these were detectable in three species tested in the Solanaceae, 3α,7β-dihydroxynortropane was, however, isolated from Duboisia leichhardtii.The dihydroxynortropanes 1, 2 and 3 were isolated from calystegine-producing plants in Convolvulaceae and Solanaceae families
Keywords: Convolvulaceae; Solanaceae; Dihydroxynortropane; Calystegine; Swainsonine;
Fatty acid profiles and their chemotaxonomy in planktonic species of Anabaena (Cyanobacteria) with straight trichomes by Renhui Li; Makoto M Watanabe (727-731).
Twenty-four axenic strains of planktonic Anabaena with straight trichomes, assigned to 7 species, were investigated by analyzing the pattern and content of their fatty acid composition and comparing their fatty acid composition with their morphological properties. In general, the fatty acids in planktonic Anabaena contained 14:0, 16:0, 16:1(cis-), 18:0, 18:1, 18:2, and 18:3(α) as their major components, and were classified as Type 2 according to the Kenyon–Murata system. These strains were further divided into 2 subtypes: 18 strains belonging to Type 2A, which contains 16:2 and 16:3, and 6 strains to Type 2B, which lacks 16:2 and 16:3. Fatty acid compositions of strains of A. solitaria, A. smithii, and A. kisseleviana closely corresponded to morphological properties; however, 10 strains of A. planctonica were divided into 4 clusters, and 3 strains of A. affinis into 2 clusters. These clusters should be taxonomically evaluated based on other aspects such as genetic characteristics.Twenty-four axenic strains of planktonic Anabaena with straight trichomes, assigned to 7 species, were investigated by analyzing the pattern and content of their fatty acid composition, and comparing their fatty acid composition with their morphological properties.
Keywords: Cyanobacteria; Fatty acid; Morphological characters; Planktonic Anabaena; Taxonomy;
Chemical variability in the essential oil of Hyptis suaveolens by Neucı́rio R Azevedo; Irani F.P Campos; Heleno D Ferreira; Tomás A Portes; Suzana C Santos; José C Seraphin; José R Paula; Pedro H Ferri (733-736).
The essential oils of Hyptis suaveolens plants collected from 11 localities of the Brazilian Cerrado region were investigated by GC–MS. Sabinene, limonene, biclyclogermacrene, β-phellandrene and 1,8-cineole were the principal constituents. The results were submitted to principal component and chemometric cluster analysis which allowed three groups of essential oils to be distinguished with respect to the content of p-mentha-2,4(8)-diene, limonene/β-phellandrene/γ-terpinene and germacrene D/bicyclogermacrene. In patterns of geographic variation in essential oil composition indicated that the sesquiterpenes are mainly produced in the samples grown at lower latitudes.The essential oils of 11 populations of Hyptis suaveolens from the Brazilian Cerrado were analysed by GC–MS and their chemical variability investigated by principal component and cluster analysis.
Keywords: Hyptis suaveolens; Lamiaceae; Essential oils; Chemical variability; Multivariate analysis;
3′,5′-Di-C-β-glucopyranosylphloretin, a flavonoid characteristic of the genus Fortunella by Kazunori Ogawa; Akemi Kawasaki; Mitsuo Omura; Toshio Yoshida; Yoshinori Ikoma; Masamichi Yano (737-742).
Dihydrochalcone derivative, 3′,5′-di-C-β-glucopyranosylphloretin (1), is present in the genus Fortunella, (F. crassifolia, F. japonica, F. margarita, F. polyandra and F. hindsii). These species accumulate a large quantity of 1 in their fruits (peel, 6.5–15.2 mg/g in dry wt; juice sac, 1.5–10.5 mg/g) and in their leaves (21.3–60.2 mg/g). Twenty-seven Tanaka's Citrus species examined lack 1, but C. madurensis and C. halimii contain 1 in large quantities in their peels (25.1 and 33.6 mg/g) and juice sacs (4.1 and 4.2 mg/g). Poncirus species do not contain 1. Fortunella-citrus hybrids, the Orangequat [C. unshiu×F. crassifolia], the Thomasville citrangequat [Fortunella sp.×(C. sinensis×Poncirus trifoliata)], and seven hybrid progenies [F. margarita×C. junos], contain large amounts of 1 in their peels (17.0–7.9 mg/g) and juice sacs (2.0–9.9 mg/g). These facts suggest that accumulation of 1 is a generic trait of the genus Fortunella and that the inheritance of the trait among the intergeneric hybrids is controlled by a dominant allele. Thus C. madurensis and C. halimii are thought to originate from natural hybrids between the genera Citrus and Fortunella. Phloridzin, which has the same aglycon as 1, was not detected in the citrus plants examined. Fortunella species, Fortunella-citrus hybrids, and Citrus madurensis and C. halimi accumulate a large amount of 3′,5′-di-C-β-glucopyranosylphloretin. Other Citrus species examined, except the species above Poncirus species, lack it. Its accumulation is a generic trait of Fortunella species, i.e. the Fortunella-citrus hybrids inherited its accumulation from the Fortunella parent.
Keywords: Fortunella; Citrus; Poncirus; Rutaceae; Hybrid; Taxonomy; Dihydrochalcone; Flavonoid; 3′; 5′-Di-C-β-glucopyranosylphloretin;
Antifungal polysulphides from Petiveria alliacea L. by Paulo José Coelho Benevides; Maria Claudia M Young; Astréa M Giesbrecht; Nı́dia F Roque; Vanderlan da S Bolzani (743-747).
Bioactivity-directed fractionation of the CH2Cl2/MeOH (2:1, v/v) extract of the roots of Petiveria alliacea, using mutant yeast strains of Saccharomyces cerevisiae and fungi Cladosporium cladosporioides and C. sphaerospermum led to the isolation of dipropyl disulphide (1), dibenzyl sulphide (2), dibenzyl disulphide (3), dibenzyl trisulphide (4), dibenzyl tetrasulphide (5), benzylhydroxymethyl sulphide (6) and di(benzyltrithio) methane (7). Of these, 5–7 are new compounds and this is the first report of the natural occurrence of 2 and 3.Bioactivity-directed fractionation of the CH2Cl2/MeOH (2:1, v/v) extract of the roots of Petiveria alliacea, using mutant yeast strains of Saccharomyces cerevisiae and fungi Cladosporium cladosporioides and C. sphaerospermum led to the isolation of dipropyl disulphide (1), dibenzyl sulphide (2), dibenzyl disulphide (3), dibenzyl trisulphide (4), dibenzyl tetrasulphide (5), benzylhydroxymethyl sulphide (6) and di(benzyltrithio) methane (7). Of these, 5–7 are new compounds and this is the first report of the natural occurrence of 2 and 3.
Keywords: Petiveria alliacea; Phytolacaceae; Antifungal polysulphides;
Endogenous gibberellins in immature seeds of Prunus persica L.: identification of GA118, GA119, GA120, GA121, GA122 and GA126 by Masayoshi Nakayama; Masaji Koshioka; Hiroyuki Matsui; Hitoshi Ohara; Lewis N Mander; Sarah K Leitch; Bruce Twitchin; Petra Kraft-Klaunzer; Richard P Pharis; Takao Yokota (749-758).
The endogenous gibberellins in immature seeds of Prunus persica were analyzed by gas chromatography–mass spectrometry. Eleven known gibberellins, GA3, GA9, GA17, GA19, GA30, GA44, GA61, GA63, GA87, GA95 and GA97 were identified. Additionally, several hitherto unknown gibberellins were detected and their putative structures were verified by synthesis of the authentic gibberellins. These gibberellins were then assigned trivial numbers, e.g. 1α-hydroxy GA20 (GA118), 1α-hydroxy GA9 (GA119), 1,2-didehydro GA9 (GA120), 1,2-didehydro GA70 (GA121), 1,2-didehydro GA69 (GA122) and 1,2-didehydro GA77 (GA126). GA118 and GA119 were the first 1α-hydroxy gibberellins identified from higher plants. The above profile of 1,2-didehydro gibberellins suggests that 1,2-dehydrogenation might occur prior to 3β-hydroxylation in biosynthesis of GA3, GA30 and GA87 in immature seeds of P. persica.Gibberellin A118, GA119, GA120, GA121, GA122 and GA126 were identified in immature seeds of Prunus persica L. as well as eleven known gibberellins.
Keywords: Prunus persica; Rosaceae; Peach; Immature seeds; Identification of gibberellins; GA118; GA119; GA120; GA121; GA122; GA126;
Occurrence of cadaverine in hairy roots of Brugmansia candida by Carla N. Carrizo; Sandra I. Pitta-Alvarez; Marcelo J. Kogan; Ana M. Giulietti; Marı́a L. Tomaro (759-763).
The polyamine, cadaverine, was detected in transformed root cultures of Brugmansia candida (syn. Datura candida), a Solanaceae which produces the tropane alkaloids scopolamine and hyoscyamine. To the best of our knowledge, this is the first time that the existence of this uncommon polyamine has been detected in a Datura species. Cadaverine, however, could not be found in the whole plant. The occurrence of cadaverine in hairy roots could be a consequence of either the transformation or a response to stress. Also, cadaverine could be participating in other secondary pathways rather than to the tropane alkaloids. The common polyamines, putrescine, spermidine and spermine were also observed.Cadaverine, an unusual polyamine, was found in transformed roots of Brugmansia candida.
Keywords: Brugmansia candida (syn. Datura candida); Solanaceae; Cadaverine; Agrobacterium rhizogenes; Hairy roots; Polyamines;
The phenolic fraction of maize bran: evidence for lignin-heteroxylan association by Catherine Lapierre; Brigitte Pollet; Marie-Christine Ralet; Luc Saulnier (765-772).
Maize bran heteroxylan samples were extracted in various conditions of severity. Their ferulate and diferulate content was investigated by GC–MS of methyl ester-TMSi derivatives. When extracted by 0.5 M NaOH in mild conditions, the heteroxylan sample contained a low level of ferulic acid (0.032% by wt.) and the main diferulate surviving alkaline extraction was found to be the 8–8′ diferulate. On peroxidase treatment, this sample nevertheless produced a firm and brittle gel without any change in the diferulate profile. Typical lignin structures, mainly comprising syringyl units interconnected through β-O-4, β-1 and β-β interunit bonds, were evidenced in the maize bran sample. More importantly, these lignin structures were found to be tightly associated with the alkali-extracted heteroxylans. Thioacidolysis revealed the occurrence of 0.1–0.5% (by wt.) lignin structures in heteroxylan fractions extracted in mild or severe conditions, before and after purification of the polysaccharides. The gelling potential of the heteroxylan fractions was not only dependent on their ferulate level, but also influenced by associated lignin structures. These results argue for the occurrence of covalent linkages between heteroxylan chains and lignin structures which could participate in the peroxidase-driven gelation of feruloylated polysaccharides. They demonstrate the role of low lignin levels in the organization of native or reconstructed polysaccharide networks.Lignin structures were found to be tightly associated with feruloylated heteroxylan samples isolated from maize bran.
Keywords: Zea mays; Gramineae; Maize bran; Cell wall; Heteroxylans; Lignin; Polysaccharides; Ferulate; Dehydrodiferulate; Thioacidolysis;
Triterpene glycosides from the roots of Sanguisorba officinalis by Yoshihiro Mimaki; Masato Fukushima; Akihito Yokosuka; Yutaka Sashida; Shigenori Furuya; Hiroshi Sakagami (773-779).
Five triterpene glycosides were isolated from the MeOH extract of Sanguisorba officinalis (Rosaceae) roots, as confirmed by detailed analysis of their 1H, 13C, and two-dimensional NMR data, and by the results of hydrolytic cleavage. Three known triterpenes and six known triterpene glycosides were also isolated and identified. The isolated compounds were evaluated for their cytotoxic activities against HSC-2 cells and HGF.Five triterpene glycosides were isolated from Sanguisorba officinalis roots, together with three known triterpenes and six known triterpene glycosides. The isolated compounds were evaluated for their cytotoxic activities against HSC-2 cells and HGF.
Keywords: Sanguisorba officinalis; Rosaceae; Triterpene glycosides; Cytotoxic activity; HSC-2 cells;
Investigation of Uña De Gato I. 7-Deoxyloganic acid and 15N NMR spectroscopic studies on pentacyclic oxindole alkaloids from Uncaria tomentosa by Ilias Muhammad; D.Chuck Dunbar; Riaz A Khan; Markus Ganzera; Ikhlas A Khan (781-785).
The C-8-(S) isomer of deoxyloganic acid (7-deoxyloganic acid), together with β-sitosteryl glucoside, five known stereoisomeric pentacyclic oxindole alkaloids and the tetracyclic oxindole isorhyncophylline, were isolated from the inner bark of Uncaria tomentosa. Structures of the isolated compounds were based on 1H and 13C NMR data, mainly 2D NMR experiments, including 1H–13C HMBC and 1H–1H NOESY correlation. Furthermore, the hitherto unreported 15N chemical shifts of the isomeric oxindole alkaloids, using 1H–15N HMBC experiments, were utilized to facilitate their characterization. Uncarine D showed weak cytotoxic activity against SK-MEL, KB, BT-549 and SK-OV-3 cell lines with IC50 values between 30 and 40 μg/ml, while uncarine C exhibited weak cytotoxicity only against ovarian carcinoma (IC50 at 37 μg/ml).
Keywords: Uncaria tomentosa; Rubiaceae; Cat's claw; Alkaloids; Oxindoles; 15N NMR; Iridoid glucoside; 7-Deoxyloganic acid; β-Sitosteryl glucoside; Cytotoxic activity;
Sterol composition of Aureoumbra lagunensis, the Texas brown tide alga by José-Luis Giner; Xiaoyong Li; Gregory L Boyer (787-789).
Aureoumbra lagunensis, the alga responsible for the “Texas brown tide”, contains (E)-24-propylidenecholesterol (35.7% of total sterols) as its dominant sterol, in common with other members of the Pelagophyceae. Other major sterols are stigmasterol (22.2%), sitosterol (19.2%), cholesterol (14.1%), and (24R)-24-propylcholesterol (5.2%). Trace amounts of 24-methylenecholesterol, crinosterol, clerosterol, campesterol, dihydrobrassicasterol, and 24-isopropylcholesterol were also detected.The sterol composition of Aureoumbra lagunensis, the causative organism of the Texas brown tide is described.
Keywords: Texas brown tide; Aureoumbra lagunensis; Pelagophyceae; Chemotaxonomy; Algal sterols;
Influence of trans-cis isomerisation of coumaric acid substituents on colour variance and stabilisation in anthocyanins by Florian George; Paulo Figueiredo; Kenjiro Toki; Fumi Tatsuzawa; Norio Saito; Raymond Brouillard (791-795).
The recently isolated pigments from Petunia integrifolia and Triteleia bridgesii present a distinct feature that sheds new light on the understanding of intramolecular copigmentation of anthocyanins. These are among the infrequent anthocyanins that naturally present a coumaric acid substituent in both cis and trans forms. As a consequence, the two isomers demonstrate substantial variations of their thermodynamic and kinetic constants and also colour properties. A possible explanation for these characteristics is presented, making use of molecular modelling and taking into account the three-dimensional structures of the pigments.Graphic
Keywords: Petunia integrifolia; Solanaceae; Triteleia bridgesii; Liliaceae; Acylated anthocyanins; Coumaric acid; trans-cis Isomerisation; Intramolecular copigmentation; Molecular modelling;
Bioactive Compounds from Natural Sources: Isolation, Characterisation and Biological Properties by Robert J Nash (797-798).
Molecular and Supramolecular Chemistry of Natural Products and Their Model Compounds by Simon Cutting (797-798).
Corrigendum to “Sesquiterpene coumarins and sesquiterpenes from Ferula sinaica” [Phytochemistry 50 (1999) 109–112] by Ahmed A Ahmed (799).
Erratum to “7β-Oxygenated limonoids from Trichilia elegans ssp. elegans” [Phytochemistry 55 (2000) 733–740] by Fernanda R Garcez; Walmir S Garcez; Nı́dia F Roque; Eduardo E Castellano; Julio Zukerman-Schpector (801).