Influence of vegetative cycle of asparagus (Asparagus officinalis L.) on copper, iron, zinc and manganese content

The essential elements copper (Cu), iron (Fe), zinc (Zn) and manganese (Mn) were analyzed in fresh asparagus to determine the effects of the vegetative cycle of the plant on the micronutrient content. Asparagus samples were classified in two groups by diameter (< 11 mm and > 14 mm). Asparagus from a sample group with the same diameter were divided into two portions (apical and basal) according to distance from the tip. The concentrations of copper, iron, zinc and manganese increased during the vegetative cycle of the asparagus, mainly in the apical portion which showed significantly greater concentrations with respect to the basal portion. The > 14 mm diameter asparagus presented higher levels of copper, zinc and manganese, whereas the concentration of iron was greater in the < 11 mm diameter asparagus. The mean element levels were (mg/kg dry weight): Cu, 18.9 +/- 3.9; Fe, 91.7 +/- 33.7; Zn, 69.5 +/- 24.6 and Mn, 20.9 +/- 5.0).

Protein expression in Arabidopsis thaliana after chronic clinorotation

Soluble protein expression in Arabidopsis thaliana L. (Heynh.) leaf and stem tissue was examined after chronic clinorotation. Seeds of Arabidopsis were germinated and plants grown to maturity on horizontal or vertical slow-rotating clinostats (1 rpm) or in stationary vertical control units. Total soluble proteins and in vivo-labeled soluble proteins isolated from these plants were analyzed by two-dimensional SDS PAGE and subsequent fluorography. Visual and computer analysis of the resulting protein patterns showed no significant differences in either total protein expression or in active protein synthesis between horizontal clinorotation and vertical controls in the Arabidopsis leaf and stem tissue. These results show chronic clinorotation does not cause gross changes in protein expression in Arabidopsis.

A new terpenoid glycoside from Nauclea diderrichii bark

A new terpenoid glycoside, marounoside [1], was isolated from the bark of Nauclea diderrichii and characterized by 1D and 2D nmr spectroscopy. The aglycone, a terpene with an unusual carbon skeleton, is linked to glucose, which, in turn, is connected to an apiofuranose residue.

[Triterpene glycosides from Hedera taurica. XIII. Structure of taurosides St-I1 and St-I2 from Crimean ivy stems]

The taurosides, St-I1 and St-I2, isolated from the stems of Crimean ivy Hedera taurica Carr. (Araliaceae), were shown to be the known glycoside, 3-O-[beta-D-glucopyranosyl-(1-->2)-O-alpha-L-arabinopyranosyl]-28- O-[alpha-L-rhamnopyranosyl-(1-->4)-O-beta-D-glucopyranosyl-(1-->6)-O-bet a-D- glucopyranosyl]hederagenin, and a new glycoside, 3-O-[alpha-L-rhamnopyranosyl-(1-->2)-O-beta-D-glucopyranosyl]-28-O-[a lpha -L-rhamnopyranosyl-(1-->4)-O-beta-D-glucopyranosyl-(1-->6)-O-beta-D- glucopyranosyl]hederagenin, respectively.

Inhibitory effect of alkaloids extracted from the stem bark of Hunteria zeylanica on 5-lipoxygenase activity in vitro

The effects of alkaloid extract from the stem bark of Hunteria zeylanica Gard. (H. zeylanica) on the activities of cyclooxygenase and 5-lipoxygenase in A23187-stimulated rat mast cells were investigated. H. zeylanica alkaloid extract (0.3-300 micrograms/ml) inhibited leukotriene C4 (LTC4) production by 5-lipoxygenase in a concentration-dependent manner and it blocked the production by 50% at 300 micrograms/ml. On the other hand, the extract had no effect on prostaglandin D2 (PGD2) production by cyclooxygenase. Neither (-)-eburnamine nor pleiomutinine, major constituents of H. zeylanica alkaloid extract, inhibited the production of PGD2 and LTC4 in the A23187-stimulated mast cells. The inhibition of arachidonic acid metabolism via 5-lipoxygenase pathway may be due to minute amounts of other components as stated in the Discussion.

Antiallergic constituents from oolong tea stem

The antiallergic constituents of oolong tea stem were examined. The stem extracts inhibited the 48 h homologous passive cutaneous anaphylaxis (PCA) reactions or rats in a dose-dependent manner and showed the same extent of inhibitory activity as ketotifen. All antiallergic constituents from the stem were concentrated into chloroform and ethyl acetate fractions, when extracted by various solvents. These fractions were treated with polyvinylpolypyrrolidone (PVPP), which resulted in the elimination of antiallergic activity in the ethyl acetate fraction, suggesting that one of the antiallergic constituents may be tea catechins. Then, six kinds of catechins, (-)-epigallocatechin gallate (EGCG), (-)-epigallocatechin (EGC), (-)-epicatechin gallate (ECG), -epicatechin (EC), (+)-catechin (C) and (-)-gallocatechin gallate (GCG), were isolated from the ethyl acetate fraction, and the inhibitory activity of these catechins on histamine release from rat peritoneal mast cells passively sensitized with anti-egg albumin (EA) IgE antibody was investigated. Among these catechins, significant inhibitory activity was observed in all the catechins except for EC. In addition, the inhibitory activity of GCG was greater than that of EGCG, which is well known to be an antiallergic constituent in tea. These results suggest that GCG may be a novel antiallergic constituent among tea catechins, and also the most potent.

[Chemical constituents of stems and leaves of Fritillaria ussuriensis Maxim]

Three compounds were isolated from stems and leaves of Fritillaria ussuriensis. They were identified as adenosine, galacitiol and succinic acid.

[Protective effects of the stem of Berchemia racemosa Sieb. et Zucc. on experimental liver injuries]

The methanol extract and water extract from the stem of Berchemia racemosa (Rhamnaceae) showed protective effects on liver injuries induced by carbon tetrachloride (CCl4) and alpha-naphthylisothiocyanate (ANIT) in rats. The acetone extract of B. racemosa protected the liver injury induced by CCl4. One of the protective substances was identified as carpusin. Some fractions showed significant protective effects against the liver injury and cholestasis induced by ANIT.

A new phenylpropanoid glucoside and other constituents of Oenanthe javanica

Three glucosides (1-3), together with known phenylpropanoids and polyacetylenes were isolated from Oenanthe javanica Blume (DC.). Glucoside 1, named oenanthoside A, is a new phenylpropanoid glucoside and was determined to be 2,3-methylenedioxy-5-allylphenyl beta-D-glucopyranoside, mainly by NMR techniques. Glucosides 2 and 3 were identified as eugenyl beta-D-glucopyranoside and pinoresinol beta-D-glucopyranoside, respectively. These were found for the first time in this plant.

Separation and characterization of Arabidopsis thaliana proteins by two-dimensional gel electrophoresis

Arabidopsis (Arabidopsis thaliana) proteins were isolated from five tissues (leaf, stem, root, seed and callus), and separated by two-dimensional gel electrophoresis (2-DE). 2-DE was carried out by immobilized pH gradient (IPG) in the first dimension, and by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) in the second dimension. With the aid of comigrated five-marker proteins, the patterns of 2-DE gels for each tissue were graphically combined by a computer into a single synthetic image for the integrated Arabidopsis protein spots. The protein spot images, altogether 4763, were characterized by both molecular mass and isoelectric point. Partial amino(N)-terminal sequences of 101 protein spots were analyzed by Edman degradation. Fifty seven proteins were partially sequenced and 46 proteins appeared to have blocked N-termini. Deblocking by hydrazine vapor was carried out on 14 proteins and two of them were found to be pyroglutamyl-blocked N-termini. Forty seven new proteins were found by the present investigation.

Expression patterns of three genes in the stem of lucerne (Medicago sativa)

We have identified three stem abundantly expressed genes in lucerne (alfalfa, Medicago sativa). A cDNA library, constructed from lucerne stem polyadenylated RNA, was screened by differential hybridization. From this screening, cDNA clones that correspond to genes which are preferentially, or specifically, expressed in the stem were isolated. MsaS1 encodes an unidentified protein, MsaS2 encodes an S-adenosyl-homocysteine hydrolase and MsaS3 encodes an extensin-like protein. Northern blot analysis of RNA isolated from individual stem internodes indicated that the three corresponding genes show differing developmental patterns of expression. The expression of MsaS1 was confined to the youngest stem tissue and may be regulated by sucrose. In stem tissue the level of RNA for the three genes decreased in response to wounding. Tissue print hybridization analysis was used to localize the expression of the genes to the xylem side of vascular bundles in lucerne stems.

Isolation and characterization of a water-stress-inducible cDNA clone from Solanum chacoense

A rich source of valuable genes are wild species. Solanum chacoense Bitter with its extreme resistance to viruses, insects and drought, is a good example. In the present study, a stress gene, designated DS2, has been isolated from S. chacoense. We have shown that the expression of the gene is organ-specific being detected in leaf, stem and stolon, but not in root, tuber or flower. Treatment of detached leaves with abscisic acid (ABA), salicylic acid or methyl jasmonate resulted in only very moderate accumulation of DS2 mRNA. Thus, DS2 represents a very rare type of the water-stress-inducible genes whose signalling pathway is not primarily related to ABA. Based on DNA sequence analysis, DS2 encodes a putative protein starting with 20 amino acids homologous to the ABA- and water-stress-inducible, ripening-related (ASR) proteins of tomato continued by an insert of 155 amino acids structurally similar to certain LEAs (late embryogenesis-abundant proteins) and ending in 88 amino acids homologous again to the ASR sequences and to an unpublished partial cDNA fragment isolated from the root of rice. The N-terminal region of the DS2 protein is hydrophilic with ten 13-mer amino acid motifs and random coil structure. In contrast, the C-terminus predicts an alpha-helix and possesses a bipartite nuclear targeting sequence motif. These data suggest that the function of the DS2 may be the protection of the nuclear DNA from desiccation.

Comparative antimicrobial study of the resinous exudates of some Chilean Haplopappus (Asteraceae)

The antimicrobiol properties and preliminary chemical information of the resinous exudates from twigs and leaves of nine Haplopappus species from Chile: H. diplopappus; H. anthylloides; H. schumannii; H. cuneifolius; H. velutinus; H. uncinatus; H. multifolius, H. illinitus and H. foliosus are presented. The results show that those species of genus Haplopappus share similar antimicrobial activities although they differ dramatically in the chemical composition.

Effects of alkaloids extracted from the stem bark of Hunteria zeylanica on acute inflammation in experimental animals

The effects of crude alkaloids extracted from the stem bark of Hunteria zeylanica GARD. (H. zeylanica) on acute inflammatory responses such as carrageenin-induced paw edema in rats and croton oil- and arachidonic acid-induced ear edema in mice were investigated. Oral administration of H. zeylanica alkaloid extract (200-400 mg/kg) significantly suppressed the paw swelling induced by carrageenin. In the croton oil-induced ear edema, topically applied H. zeylanica alkaloid extract, at doses of 200 and 400 mg/ml, also significantly reduced ear edema. Moreover, the extract (50-200 mg/kg, p.o.) reduced in a dose-dependent manner the ear swelling induced by topically applied arachidonic acid (2 mg/ear). These results suggest that the inhibitory effects of H. zeylanica alkaloid extract on acute edema formation are partly due to inhibition of 5-lipoxygenase and cyclooxygenase activity.

Cytotoxic aromatic triterpenes from Maytenus ilicifolia and Maytenus chuchuhuasca

The isolation and structure elucidation of four cytotoxic aromatic triterpenes [1-4] along with three known quinoid triterpenes [5-7] from the South American medicinal plants Maytenus ilicifolia and M. chuchuhuasca are described. The structures of these aromatic triterpenes contained aromatized A rings and C-6 oxygenated B rings, and were elucidated by 1H- and 13C-nmr spectroscopic studies and by X-ray crystallographic analysis of 3.

[Chemical constituents of roots, rhizomes and stems of Amomum villosum Lour]

Ethyl octacosate, docosyl hexylate, a new compound stigmast-4-ene-1,3-dione, beta-sitosterol and daucosterol were isolated and identified from the roots and rhizomes of Amomum villosum cultivated in Xishuangbanna, Yunnan. Two compounds daucosterol and emodin monoglycoside were isolated and identified from the stems of A. villosum.

Antisweet natural products. XI. Structures of sitakisosides VI-X from Stephanotis lutchuensis Koidz. var. japonica

From the fresh stem of Stephanotis lutchuensis var. japonica, five new oleanane-type triterpenoid glycosides named sitakisosides VI-X (1-5) were isolated. Their structures were determined on the basis of spectroscopic data and chemical evidence. Sitakisosides VI and VII are 3-O-beta-D-xylopyranosyl(1-->6)-beta-D-glucopyranosyl(1-->6)-beta-D- glucopyranosido-21-O-(6-N-methylanthranilyl)-beta-D-glucopyr anosyl and 3-O-beta-D-xylopyranosyl(1-->6)-beta-D-glucopyranosyl(1-->6)-beta-D- glucopyranosido-21-O-(4-N-methylanthranilyl)-beta-D-glucopyr anosyl sitakisogenin, respectively. Sitakisoside VIII is 3-O-beta-D-xylopyranosyl(1-->6)-beta-D- glucopyranosyl(1-->6)-beta-D-glucopyranosido-21-O-N-methylanthr anilyl- 3 beta,16 beta,21 beta,28-tetrahydroxyolean-12-ene-22-one. Sitakisoside IX is 3-O-beta-D-xylopyranosyl(1-->6)-beta-D-glucopyranosyl(1-->6)-beta-D- glucopyranosido-21-O-(6-N-methylanthranilyl)-beta-D-glucopyr anosyl gymnestrogenin. Sitakisoside X is 3-O-beta-D-xylopyranosyl(1-->6)-beta-D- glucopyranosyl(1-->6)-beta-D-glucopyranosyl longispinogenin.

Laboratory evaluation of interception and translocation of 131I in fenugreek and okra plants

The work reported here deals with the study of interception and translocation of airborne 131I in fenugreek (Trigonella foenum-graecum) and okra (Hibiscus esculentus), two very common vegetables in India. Activity was injected into the experimental chamber in the form of iodide aerosols having a size distribution of 0.3 to 5.0 microns (AMAD). Samples of plants were collected over a period of a few days at different time intervals after injection of the aerosols. Evaluation of interception with deposition and translocation of 131I was done from the activity measured in air and in plant parts. For the deposition factor, the values are 1.22 m3 kg-1 for fenugreek leaves, and 1.49 m3 kg-1 for the plant as a whole. For okra plants these values are 0.02 and 0.16 m3 kg-1 in edible okra and leaves, respectively. For the okra plant as a whole, the value is 0.19 m3 kg-1. The translocation factors vary from 0.62 to 0.86 and 0.47 to 0.87 for leaves and stem, respectively, in the case of fenugreek plants. For okra plants, the translocation factor varies from 0.21 to 0.82, 0.53 to 0.93, and 0.42 to 0.81 in edible okra, leaves, and stems, respectively.

Antinociceptive and antipyretic effects of alkaloids extracted from the stem bark of Hunteria zeylanica

Effects of crude alkaloids extracted from the stem bark of Hunteria zeylanica Gard. (H. zeylanica) on nociceptive responses, capillary permeability, yeast-induced hyperthermia, pentobarbital-induced sleep, and spontaneous motor activity were investigated. Oral administration of 50 mg/kg H. zeylanica alkaloid extract significantly decreased the number of writhings induced by intraperitoneal acetic acid. The extract at 100-200 mg/kg significantly increased nociceptive threshold of the inflamed but not the non-inflamed paw in the Randall-Selitto test. Moreover, in the formalin test, the extract (100 mg/kg) significantly decreased licking activity in the late phase without affecting the activity in the early phase. However, the extract did not produce antinociceptive effect in the hot plate test, while it inhibited increase of vascular permeability induced by acetic acid in the capillary permeability test. Moreover, the extract dose-dependently reduced yeast-induced hyperthermia in rats without affecting normothermia. It did not affect pentobarbital-induced sleep, but significantly increased locomotor activity at 100 mg/kg. These results suggest that H. zeylanica alkaloid extract possesses antinociceptive and antipyretic effects, and that the former effect may be mediated by its anti-inflammatory action.

The Chlorella virus adenine methyltransferase gene promoter is a strong promoter in plants

An upstream region isolated from a eukaryotic algal virus adenine methyltransferase gene was tested for promoter function in plants. Fusion of this region to the chloramphenicol acetyltransferase reporter gene resulted in significantly higher expression than fusion with the cauliflower mosaic virus 35S promoter. Strong levels of expression were also found in electroporated monocot plant cells. The promoter activity in transgenic tobacco plants showed tissue-specific expression. Leaves had the highest expression followed by stems and flowers. The promoter activity was not detected in root tissue. Environmental cues, such as light, and the phytohormones auxin and cytokinines had no effect on the promoter's expression. This promoter might be utilized to achieve high levels of expression of introduced genes in higher plants.

Modification of lignin biosynthesis in transgenic Nicotiana through expression of an antisense O-methyltransferase gene from Populus

An aspen lignin-specific O-methyltransferase (bi-OMT; S-adenosyl-L-methionine: caffeic acid/5-hydroxyferulic acid 3/5-O-methyltransferase, EC 2.1.1.68) antisense sequence in the form of a synthetic gene containing the cauliflower mosaic virus 35S gene sequences for enhancer elements, promoter and terminator was stably integrated into the tobacco genome and inherited in transgenic plants with a normal phenotype. Leaves and stems of the transgenes expressed the antisense RNA and the endogenous tobacco bi-OMT mRNA was suppressed in the stems. Bi-OMT activity of stems was decreased by an average of 29% in the four transgenic plants analyzed. Chemical analysis of woody tissue of stems for lignin building units indicated a reduced content of syringyl units in most of the transgenic plants, which corresponds well with the reduced activity of bi-OMT. Transgenic plants with a suppressed level of syringyl units and a level of guaiacyl units similar to control plants were presumed to have lignins of distinctly different structure than control plants. We concluded that regulation of the level of bi-OMT expression by an antisense mechanism could be a useful tool for genetically engineering plants with modified lignin without altering normal growth and development.

Characterization of a predominantly pistil-expressed gene encoding a gamma-thionin-like protein of Petunia inflata

We isolated a cDNA clone from a pistil cDNA library of Petunia inflata which encodes a protein, PPT, with sequence similarity to gamma-thionins. Characterization of a genomic clone containing a PPT gene revealed the presence of a single intron. Northern analysis revealed that the PPT gene was predominantly expressed in the pistil during all stages of flower development. Since thionins have been implicated in plant defense against pathogens, PPT may play a role similar to that of other defense-related proteins found in the pistil, defending the pistil against pathogen infection.

Antisweet natural products. X. Structures of sitakisosides I-V from Stephanotis lutchuensis Koidz. var. japonica

From the fresh stem of Stephanotis lutchuensis var. japonica, we have isolated five new oleane glycosides named sitakisosides I-V (1-5). Their structures were determined on the basis of spectroscopic data and chemical evidence. Sitakisoside V showed the strongest antisweet activity among sitakisosides I-V.

Expression patterns of novel genes encoding homeodomain leucine-zipper proteins in Arabidopsis thaliana

A recently discovered class of genes in Arabidopsis thaliana encode putative transcription factors which contain a homeodomain closely linked to a leucine zipper motif. We have previously reported on the cloning and cDNA sequence of one gene of this class, Athb-3. In this article we show this gene to be expressed predominantly in the cortex of the root and the stem. Using the Athb-3 clone as a probe we have isolated cDNA clones corresponding to three novel homeodomain-leucine zipper proteins. These clones, Athb-5, Athb-6 and Athb-7, hybridized to transcripts that were relatively abundant in the leaf, but also present in other vegetative organs, as well as in the flower. Only weak hybridization was observed to seed pod samples. These observations indicate that these Athb genes have major functions in the mature plant, and therefore, in contrast to homeobox genes in other eukaryotes and to the kn-1 gene in maize, are unlikely to function in the primary control of developmental processes during embryogenesis or organogenesis. The deduced amino acid sequences of Athb-5, Athb-6 and Athb-7 are highly similar to the previously isolated Athb-1, Athb-2 and Athb-3 in the homeodomain and leucine-zipper parts of the proteins, whereas the similarities to homeodomain proteins from other eukaryotes are limited. The Athb proteins thus constitute a new and well defined class of homeodomain proteins, apparently unique to plants.

Molecular cloning of two different ACC synthase PCR fragments in carnation flowers and organ-specific expression of the corresponding genes

Degenerate oligonucleotides to highly conserved regions of 1-aminocyclopropane-1-carboxylic acid (ACC) synthase (EC 4.4.1.14), the key enzyme in ethylene biosynthesis, were used to prime the synthesis and amplification of fragments of about 1,180 bp by polymerase chain reaction (PCR) in samples of cDNA to total RNA isolated from senescing carnation (Dianthus caryophyllus) flowers. Two putative ACC synthase PCR clones were isolated one of which was identical to the sequence of a carnation ACC synthase cDNA clone (CARACC3) recently isolated by Park et al. (Plant Mol Biol 18 (1992) 377-386). The other clone (CARAS1) was ca. 66% homologous at the amino acid level to CARACC3. For both ACC synthase clones, specific oligonucleotides were synthesized and, using PCR, we were able to distinguish between the two ACC synthase transcripts in samples of total RNA isolated from different carnation flower parts and leaves. DNA blots of PCR fragments revealed that, in flowers, both ageing and ethylene stimulated the occurrence of these transcripts in an organ-specific way. CARACC3 was more abundant in RNA from the petals whereas CARAS1 was more abundant in RNA from the styles. Despite a high ethylene production observed in ovaries, the level of both transcripts was low, suggesting the existence of a third ACC synthase gene that is specifically expressed in the ovary. Transcript levels in leaves were low irrespective of treatment.

Genetic complementation of a floral homeotic mutation, apetala3, with an Arabidopsis thaliana gene homologous to DEFICIENS of Antirrhinum majus

Among the homeotic mutants with altered floral organs, two mutants of Arabidopsis thaliana, apetala3 and pistillata, and two mutants of Antirrhinum majus, deficiens and globosa, have a homeotic conversion of the floral organs in whorl 2 and 3, namely petals to sepals and stamens to carpels. We have isolated a homologue of the DEFICIENS gene from A. thaliana wild type and shown complete complementation of apetala3 mutation by introducing the isolated gene using Agrobacterium-mediated transformation. These results show that the APETALA3 is a homologue of DEFICIENS structurally and functionally. The 5'-upstream region of APETALA3 contains three SRE-like sequence, where MADS box-containing proteins are assumed to bind and regulate expression in tissue- and stage-specific manner.

[The effects of Panax quinquefolium saponin (PQS) and its monomer ginsenoside on heart]

Experiments have shown that PQS (0.03-3 mg/ml) can inhibit the contractility of papillary muscle of guinea pigs, and on depolarized sample of papillary muscle with high potassium, PQS (0.03-0.3 mg/ml) can increase this contractility. Monomer saponin-Re (10 mg/kg),-Rb3 (30 mg/kg) can inhibit the hemodynamic indication of rats, but pseudogisenoside-F11 (10 mg/kg) acts the other way round. These results prove that PQS contains two components of opposite actions.

Floral expression of a gene encoding an E2-related ubiquitin-conjugating protein from Arabidopsis thaliana

An Arabidopsis thaliana gene (UBC6) encoding a homologue to ubiquitin-conjugating enzymes has been isolated which is capable of encoding a protein of 183 amino acids of ca. 21 kDa. Northern analysis indicates that the gene is expressed in flowers, seeds and, to a somewhat lesser extent, in 10-day seedlings but not in mature leaves, callus and pre-flowering plants. This pattern of expression is confirmed using transgenic Arabidopsis plants containing a UBC6 promoter-GUS gene fusion construct. These plants display GUS activity in mature anthers prior to dehiscence, in developing embryos, sepals and the style after pollination.

Steroidal constituents from the roots and stems of Aclepias fruticosa

Steroidal constituents from the roots and stems of Asclepias fruticosa L. were investigated separately. From the roots, twelve pregnane pentaosides and uzarigenin beta-sophoroside were isolated together with three known coroglaucigenin and corotoxigenin glycosides. Pregnane glycosides were composed of ikemagenin or kidjolanin as an aglycone, and D-digitoxose, D-cymarose, D-oleandrose and terminal D-glucose as component sugars. Among the constituents from the stems, cardenolides show a similar pattern to those from leaves. 17 alpha-Hydroxycalactin and 17 alpha-hydroxyafroside were newly obtained along with known doubly linked and normally linked glycosides. Two pregnane glycosides and uzarigenin beta-sophoroside obtained from the roots were also isolated.

Antibacterial triterpenoid acids from Dillenia papuana

Three new oleanene-type triterpenoids, dillenic acids A [1], B [2], and C [3], and two known compounds, 3-oxoolean-1,12-dien-30-oic acid [4] (a new natural product) and the lupene derivative betulinaldehyde, have been isolated from the Papua New Guinean medicinal plant Dillenia papuana. The structures of the new compounds were elucidated as 2 alpha-hydroxy-3-oxoolean-12-en-30-oic acid, 2-oxo-3 beta-hydroxyolean-12-en-30-oic acid and 1 alpha-hydroxy-3-oxoolean-12-en-30-oic acid. The 1H- and 13C-nmr data of all new compounds were assigned unambiguously using a variety of 2D nmr experiments including 1H-1H-COSY, HMQC, HMBC, and NOESY experiments. Of these compounds, 1-4 showed antibacterial activities against Bacillus subtilis, Escherichia coli, and Micrococcus luteus.

Purification of lectins from the stems of peanut plants

The stem of the peanut plant contains two lectins, a methyl alpha-mannoside specific lectin (SL-I) and a lactose/cellobiose specific lectin (SL-II). These lectins are found to be developmentally regulated and maximum activities are observed in 3-4-weeks-old plants. The two lectins SL-I and SL-II have been purified from 3-week-old stem by affinity chromatography on Sephadex G-50 and guar gum matrices respectively. Both are glycosylated lectins and have the identical subunit molecular weight of 31 kDa.

Isolation and structure elucidation of new taxoids from Taxus brevifolia

An investigation of Taxus brevifolia extracts afforded two taxoids characterized by the A-nortaxol ring system. These were identified as 7,13-dideacetyl-9,10- debenzoyltaxchinin C [1] and 9-deacetyl-9-benzoyl-10-debenzoylbrevifoliol [4]. Structures were elucidated by spectroscopic methods, and in particular by comparison of nmr data with those of taxchinin C and brevifoliol.

New aporphine alkaloids from guatteria foliosa

Four new alkaloids were obtained from Guatteria foliosa, namely, the noraporphines (-)-3-methoxyputerine [1] and (+)-norguattevaline [2], the more highly oxidized (+)-3-methoxyguattescidine [3], and the oxoaporphine 3-methoxyoxoputerine [4]. Among several other known alkaloids also found in this same plant, (-)-3-hydroxynornuciferine, (-)-isoguattouregidine, and argentinine exhibited significant activity against Trypanosoma cruzi.

Novel use of positively charged nylon transfer membranes for trapping indoleacetic acid or other small anions during efflux from plant tissues

Positively charged nylon blotting membranes were used as an anion binding medium to trap [14C]indoleactic acid (IAA) as it exited cells at the basal ends of Coleus blumei L. stem and Zea mays L. coleoptile segments. Autoradiography was used to visualize where the [14C] that moved out of the cut ends was localized on the nylon membrane. Diffusion of [14C]IAA from the initial point of contact with the nylon membrane was minimal. Comparison of the autoradiograms with anatomical tissue prints of the cut ends of the segments was used to determine what tissues participate in IAA movement. The results of these initial studies were consistent with other reports suggesting that [14C]IAA movement was primarily associated with vascular tissues in both C. blumei stems and corn coleoptiles, but the resolution was not sufficient to identify which vascular tissues were involved in IAA transport. With further refinements, this technique could also be used for studying the movement of other small charged molecules through plant tissues.

Saponins from the stem bark of Kalopanax pictum var. magnificum (I)

Three triterpenoid saponins were isolated from the methanol extract of the stem bark of Kalopanax pictum Nakai var. magnificum (Araliaceae). The structures of these saponins were identified as hederagenin 3-O-alpha-L-arabinopyranoside, hederagenin-3-O-alpha-L-rhamnopyranosyl(1-->2)-alpha-L-arabinop yranoside and 3-O-alpha-L-rhamnopyranosyl(1-->2)-alpha-L-arabinopyranosyl hederagenin 28-O-alpha-L-rhamnopyranosyl(1-->4)-beta-D- glucopyranosyl(1-->6)-beta-D-glucopyranosyl ester.

Effect of ammonium sulfate, ammonium chloride and root-zone acidity on inorganic ion content of tobacco

Tobacco plants (Nicotiana tabacum L. cv NC82) were supplied with (NH4)2SO4 or NH4Cl at root-zone pH of 6.0 and 4.5 in hydroponic culture for 28 days. Dry matter accumulation, total N and C content, and leaf area and number were not affected by the NH4+ source or root-zone pH. Plants supplied with NH4Cl accumulated up to 1.2 mM Cl g DW-1, but accumulated 37% less inorganic H2PO4- and 47% less SO4(2-) than plants supplied with (NH4)2SO4. The large Cl- accumulation resulted in NH4Cl- supplied plants having a 31% higher inorganic anion (NO3-, H2, PO4-, SO4(2-), and Cl-) charge. This higher inorganic anion charge in the NH4Cl-supplied plants was balanced by a similar increase in K+ charge. Plants supplied with NH4Cl accumulated greater concentrations of Cl- in leaves (up to 5.1% of DW) than plants supplied with (NH4)2SO4 (less than -% DW). Despite the high Cl- concentration of leaves in NH4Cl supplied plants, these plants showed no symptoms of Cl- toxicity. This demonstrates that toxicity symptoms are not due solely to an interaction between high Cl- concentration in tissue and NH4+ nutrition. The increase in root-zone acidity to pH 4.5 from 6.0 did not induce toxicity symptoms.

Productivity and food value of Amaranthus cruentus under non-lethal salt stress

Stress effects from the accumulation of metal salts may pose a problem for plants in closed biological systems such as spacecraft. This work examined the effects of salinity on growth, photosynthesis and carbon allocation in the crop plant, Amaranthus. Plants were germinated and grown in modified Hoagland's solution with NaCl concentrations of 0 to 1.0%. Plants received salt treatments at various times in development to assess effects on particular life history phases. For Amaranthus cruentus, germination, vegetative growth, flowering, seed development and yield were normal at salinities from 0 to 0.2%. Inhibition of these phases increased from 0.2 to 0.4% salinity and was total above 0.5%. 1.0% salinity was lethal to all developmental phases. Onset of growth phases were not affected by salinity. Plants could not be adapted by gradually increasing salinity over days or weeks. Water uptake increased, while photosynthetic CO2 uptake decreased with increasing salinity on a dry weight basis during vegetative growth. Respiration was not affected by salinity. After flowering, respiration and photosynthesis decreased markedly, such that 1.0% NaCl inhibited photosynthesis completely. Protein levels were unchanged with increasing salinity. Leaf starch levels were lower at salinities of 0.5% and above, while stem starch levels were not affected by these salinities. The evidence supports salt inhibition arising from changes in primary biochemical processes rather than from effects on water relations. While not addressing the toxic effects of specific ions, it suggests that moderate salinity per se need not be a problem in space systems.

Nodule activity and allocation of photosynthate of soybean during recovery from water stress

Nodulated soybean plants (Glycine max [L.] Merr. cv Ransom) in a growth-chamber study were subjected to a leaf water potential (psi w) of -2.0 megapascal during vegetative growth. Changes in nonstructural carbohydrate contents of leaves, stems, roots, and nodules, allocation of dry matter among plant parts, in situ specific nodule activity, and in situ canopy apparent photosynthetic rate were measured in stressed and nonstressed plants during a 7-day period following rewatering. Leaf and nodule psi w also were determined. At the time of maximum stress, concentration of nonstructural carbohydrates had declined in leaves of stressed, relative to nonstressed, plants, and the concentration of nonstructural carbohydrates had increased in stems, roots, and nodules. Sucrose concentrations in roots and nodules of stressed plants were 1.5 and 3 times greater, respectively, than those of nonstressed plants. Within 12 hours after rewatering, leaf and nodule psi w of stressed plants had returned to values of nonstressed plants. Canopy apparent photosynthesis and specific nodule activity of stressed plants recovered to levels for nonstressed plants within 2 days after rewatering. The elevated sucrose concentrations in roots and nodules of stressed plants also declined rapidly upon rehydration. The increase in sucrose concentration in nodules, as well as the increase of carbohydrates in roots and stems, during water stress and the rapid disappearance upon rewatering indicates that inhibition of carbohydrate utilization within the nodule may be associated with loss of nodule activity. Availability of carbohydrates within the nodules and from photosynthetic activity following rehydration of nodules may mediate the rate of recovery of N2-fixation activity.

Shoot inversion inhibition of stem elongation in Pharbitis nil: a possible role for ethylene-induced glycoprotein and lignin

Inversion of the upper shoot of Pharbitis nil results in the inhibition of elongation in the inverted stem. The objective of the present study was to determine how shoot inversion-induced gravity stress inhibited elongation and to elucidate the possible role of ethylene-induced glycoprotein and lignin in this process. Determinations of hydroxyproline, peroxidase, phenylalanine ammonia-lyase (PAL), phenol, and lignin content/activity were carried out by appropriate spectrophotometric methods. It was found that inversion and Ethrel treatments of upright shoots caused significant increases in hydroxyproline content, peroxidase, and PAL activity in 12 hours and in phenol and lignin contents in 24 hours. All of these increases except for that of cytoplasmic peroxidase activity were partially reversed by AgNO3, the ethylene action inhibitor. It is concluded that possible cross-linking associated with the accumulation of the ethylene-induced hydroxyproline-rich glycoprotein and lignin may be responsible for the later stages of cessation of elongation in the inverted Pharbitis shoot.