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PubMed2004

Identification of secondary metabolites in medicinal and spice plants by NIR-FT-Raman microspectroscopic mapping.

This paper demonstrates the special potential of vibrational NIR FT Raman microspectroscopy for the study of fennel fruits, chamomile inflorescence and curcuma roots to obtain detailed information about their microstructure and chemical composition. Microscopic Raman maps of fennel fruits demonstrate that anethole, which is the main essential oil component, is present in the whole mericarp with highest concentration at the top of the fruit. In situ measurements obtained of the essential oil cells are dominated by two bands observed at 1657 cm(-1) and 1609 cm(-1) which are characteristic for anethole. Raman images of chamomile inflorescence show that spiroethers, identified by significant bands between 2150 and 2250 cm(-1), are accumulated in the middle part of the flower head. Due to the intense curcumin bands in the Raman spectrum of curcuma root, the distribution of this dyeing substance can be clearly determined; highest concentration of curcumin was observed on the core of the root.

Flowering Tops↗
PubMed2004

Rosmarinic acid from Zataria multiflora tops and in vitro cultures.

Rosmarinic acid (RA) was obtained from Zataria multiflora tops' extract and its structure was confirmed by spectroscopic methods. Various in vitro cultures were established on Murashige and Skoog (MS) or Modified Tobacco (MT) medium containing growth hormones. The results indicated that cultures of Z. multiflora biosynthesize RA (55-355 mg/100 g dry wt.) and the highest accumulation were reached on MT media containing NAA 2 mg/l.

Cells, Cultured↗
PubMed2005

Endophytic yeasts and filamentous fungi associated with southern Brazilian apple (Malus domestica) orchards subjected to conventional, integrated or organic cultivation.

Endophytic fungi were isolated from leaves, flowers and fruit of healthy apple trees (Malus domestica , Borkh.) growing in southern Brazilian orchards under three different cultivation systems (conventional, integrated and organic), during two vegetative cycles. The greatest total number of endophytic isolates was obtained from the orchards under organic cultivation when compared to integrated and conventional cultivation systems. Filamentous fungi from the genera Colletotrichum , Xylaria and Botryosphaeria were the most frequent ones and the most representative yeast genera were Sporobolomyces , Rhodotorula , Debaryomyces and Cryptococcus . It is suggested that some isolates may be used as indicators of the different management systems.

Brazil↗
PubMed2002

Antibacterial and antifungal activity of essential oils of Mentha suaveolens.

The essential oils (EO) of Mentha suaveolens, a wild Labiatae, which grows in several regions in Morocco, were characterized and their antimicrobial activity assessed. The main aromatic constituents of this plant, as characterized by IR, NMR and MS studies, were pulegone, piperitenone oxide (PEO) and piperitone oxide (PO) occurring in different amounts depending on the subspecies. These constituents as well as a series of other aromatic products such as carvone, limonene and menthone, were tested for their antimicrobial activity against 19 bacteria including Gram-positive and Gram-negative and against three fungi, using solid phase and microtitration assays. Pulegone-rich essential oil inhibited efficiently all the micro-organisms tested with MICs ranging between 0.69 and 2.77 ppm. Among the components from Mentha suaveolens EO, pulegone was the most effective against the tested microorganisms, followed by PEO and PO. The structure-activity relationship is discussed on the basis of the activity of the other aromatic derivatives tested such as carvone, limonene, menthone and the profile of the essential oils of Mentha suaveolens was compared with other Mentha species.

Anti-Bacterial Agents↗
PubMed2002

Evaluation of the central properties of several Hypericum species from the Canary Islands.

The infusions of the aerial parts in blossom of Hypericum canariense, H. glandulosum, H. reflexum and H. grandifolium (Hypericaceae) were evaluated for their pharmacological activity on the central nervous system in mice using various behavioural models including locomotor and muscle relaxant activity, effect on normal body temperature, pentobarbital-induced sleep, oxotremorine and tetrabenazine-induced syndrome, apomorphine-induced hypothermia and 5-hydroxytryptophan-induced head twitches, as well as a forced swimming test. These infusions did not alter significantly the locomotor activity, pentobarbital induced sleeping time and body temperature, with the exception of H. canariense which produced a slight but significant hypothermia. Additionally, no muscle relaxant or anticholinergic activity were observed. These infusions antagonized the ptosis and/or motor depression induced by tetrabenazine as well as shortening the immobility time in the forced swimming test. The observations suggest that the infusions of these Hypericum species possess antidepressant activity in mice, without inducing muscle relaxation, anticholinergic and sedative properties.

Administration, Oral↗
PubMed2005

Antiallergic and antihistaminic effect of two extracts of Capparis spinosa L. flowering buds.

The antiallergic properties of two lyophilized extracts obtained from Capparis spinosa L. flowering buds (capers) by methanol extraction, carried out at room temperature (CAP-C) or with heating at 60 degrees C (CAP-H), were investigated. The protective effects of CAP-H and CAP-C, orally administered (14.28 mg[sol ]kg), were evaluated against Oleaceae antigen challenge-induced and histamine-induced bronchospasm in anaesthetized guinea-pigs. Furthermore, the histamine skin prick test was performed on humans, applying a gel formulation containing 2% CAP-C (the only extract able to protect against histamine-induced bronchospasm) on the skin for 1 h before histamine application and monitoring the erythema by reflectance spectrophotometry. The CAP-H showed a good protective effect against the bronchospasm induced by antigen challenge in sensitized guinea-pigs; conversely, a significant decrease in the responsiveness to histamine was seen only in CAP-C pretreated animals. Finally, the CAP-C gel formulation possessed a marked inhibitory effect (46.07%) against histamine-induced skin erythema. These two caper extracts displayed marked antiallergic effectiveness; however, the protective effect of CAP-H was very likely due to an indirect mechanism (for example, inhibition of mediator release from mast cells or production of arachidonic acid metabolites); conversely, CAP-C is endowed with direct antihistaminic properties. The different mechanisms of action of CAP-H and CAP-C may be related to a difference in the extraction procedure and, thus, in their qualitative[sol ]quantitative chemical profile.

Administration, Oral↗
PubMed2003

Genetic and morphological characterization of the barley uniculm2 (cul2) mutant.

Axillary meristem growth and development help define plant architecture in barley (Hordeum vulgare L). Plants carrying the recessive uniculm2 (cul2) mutation initiate vegetative axillary meristem development but fail to develop tillers. In addition, inflorescence axillary meristems develop into spikelets, but the spikelets at the distal end of the inflorescence have an altered phyllotaxy and are sometimes absent. Double mutant combinations of cul2 and nine other recessive mutations that exhibit low to high tiller number phenotypes resulted in a uniculm vegetative phenotype. One exception was the occasional multiple shoots produced in combination with granum-a; a high tillering mutant that occasionally produces two shoot apical meristems. These results show that the CUL2 gene product plays a role in the development of axillary meristems into tillers but does not regulate the development of vegetative apical meristems. Moreover, novel double-mutant inflorescence phenotypes were observed with cul2 in combination with the other mutants. These data show that the wild-type CUL2 gene product is involved in controlling proper inflorescence development and that it functions in combination with some of the other genes that affect branching. Our genetic analysis indicates that there are genetically separate but not distinct regulatory controls on vegetative and inflorescence axillary development. Finally, to facilitate future positionally cloning of cul2, we positioned cul2 on chromosome 6(6H) of the barley RFLP map.

Chromosome Mapping↗
PubMed2006

Fine mapping of a quantitative trait locus for grain number per panicle from wild rice (Oryza rufipogon Griff.).

SIL040, an introgression line (IL) developed by introgressing chromosomal segments from an accession of Oryza rufipogon into an indica cultivar Guichao 2, showed significantly less grains per panicle than the recurrent parent Guichao 2. Quantitative trait locus (QTL) analysis in F2 and F3 generations derived from the cross between SIL040 and Guichao 2 revealed that gpa7, a QTL located on the short arm of chromosome 7, was responsible of this variation. Alleles from O. rufipogon decreased grains per panicle. To fine mapping of gpa7, a high-resolution map with 1,966 F2 plants derived from the cross between SIL040 and Guichao 2 using markers flanking gpa7 was constructed, and detailed quantitative evaluation of the structure of main panicle of each of F3 families derived from recombinants screened was performed. By two-step substitution mapping, gpa7 was finally narrowed down to a 35-kb region that contains five predicted genes in cultivated rice. The fact that QTLs for five panicle traits (length of panicle, primary branches per panicle, secondary branches per panicle, grains on primary branches and grains on secondary branches) were all mapped in the same interval as that for gpa7 suggested that this locus was associated with panicle structure, showing pleiotropic effects. The characterizing of panicle structure of IL SIL040 further revealed that, during the domestication from common wild allele to cultivated rice one at gpa7, not only the number of branches and grains per panicle increased significantly, more importantly, but also the ratio of secondary branches per panicle to total branches per panicle and the ratio of grains on secondary branches per panicle to total grains per panicle increased significantly. All these results reinforced the idea that gpa7 might play an important role in the regulation of grain number per panicle and the ratio of secondary branches per panicle during the domestication of rice panicle.

Alleles↗
PubMed2006

The introgression of chromosome 6P specifying for increased numbers of florets and kernels from Agropyron cristatum into wheat.

A wheat (Triticum aestivum L.) line 4844 with superior numbers of florets and grains per spike was derived from the cross between Fukohokomugi wheat and Agropyron cristatum (L.) Gaertn. In order to determine the genetic control of floret and kernel number per spike in this line, chromosome addition and substitution lines that were derived from line 4844 were characterized by means of in situ hybridization, microsatellite (SSR), and gliadin analyses. Genomic in situ hybridization analysis with biotinylated P genomic DNA of A. cristatum as a probe demonstrated that the increased number of florets and grains in a spike was associated with the introgression of an A. cristatum chromosome. Fluorescence in situ hybridization, using a repetitive sequence, pAs1, derived from Aegilops squarrosa L., indicated the replacement of chromosome 6D of wheat in the wheat-A. cristatum chromosome substitution lines. This was confirmed by microsatellite analyses with wheat SSR markers specific for chromosome 6D, suggesting that the A. cristatum chromosome was homoeologous to group 6 and was therefore designated as 6P. This conclvsion was further confirmed by amplification using EST-SSR markers and gliadin analysis. The increased number of florets and kernels within a spike of the wheat-A. cristatum hybrids thus was controlled by gene(s) located on A. cristatum chromosome 6P.

Agropyron↗
PubMed2006

Identification and mapping of a tiller inhibition gene (tin3) in wheat.

Tillering is one of the most important agronomic traits in cereal crops because tiller number per plant determines the number of spikes or panicles per plant, a key component of grain yield and/or biomass. In order to characterize the underlying genetic variation for tillering, we have isolated mutants that are compromised in tillering ability using ethyl methanesulphonate (EMS)-based mutagenesis in diploid wheat (Triticum monococcum subsp. monococcum). The tillering mutant, tiller inhibition (tin3) produces only one main culm compared to the wild type with many tillers. The monoculm phenotype of tin3 is due to a single recessive mutation. Genetic and molecular mapping in an F(2) population of diploid wheat located the tin3 gene on the long arm of chromosome 3A(m). One codominant RFLP marker Xpsr1205 cosegregated with tin3 in the F(2) population. Physical mapping of PSR1205 in a set of Chinese Spring deletion lines of group-3 chromosomes placed the tin3 gene in the distal 10% of the long arm of chromosome 3A, which is a recombination-rich region in wheat. The implications of the mapping of tin3 on chromosome arm 3A(m)L are discussed with respect to putative orthologs of tin3 in the 3L colinear regions across various cereal genomes and other tillering traits in grasses.

Chromosome Mapping↗
PubMed2006

Biodiversity and biogeography of Fusarium species from northeastern North American asparagus fields based on microbiological and molecular approaches.

Sixteen Fusarium species were recovered from 52 asparagus commercial fields, representing all major ecological (edaphic and climatic) area of asparagus production in the province of Québec, eastern Canada. This study extends our understanding of the geographic range of these species. It also provides climatological and edaphic properties linked to community changes and adaptations. Fusarium oxysporum and F. proliferatum were omnipresent and abundant in all five ecological area under study, whereas F. redolens was less frequently found. Species of Fusarium that produce carmine red pigmentation on potato dextrose agar, i.e., F. acuminatum, F. avenaceum, etc., were common at the northern limit of asparagus production. Abundance of red Fusarium species corresponded with a low isolation frequency of F. proliferatum. Nevertheless, F. proliferatum had a high recovery rate throughout Québec asparagus growing areas, under climatic conditions as cold as those of northern Europe where this species is uncommon in asparagus fields. In the light of these results, redefinition of the geographical distribution of F. proliferatum in asparagus fields is proposed. Intraspecific molecular differences in F. proliferatum and F. oxysporum were detected in the EF-1 alpha sequences and compared with well-characterized strains of North America.

Agriculture↗
PubMed2006

Arabidopsis inflorescence architecture requires the activities of KNOX-BELL homeodomain heterodimers.

In flowering plants, post-embryonic development is mediated by the activity of shoot and root apical meristems. Shoot architecture results from activity of the shoot apical meristem (SAM), which initiates primordia, including leaves, internodes and axillary meristems, repetitively from its flanks. Axillary meristems can develop into secondary shoots or flowers. In Arabidopsis, two paralogous BEL1-like (BELL) homeobox genes, PENNYWISE (PNY) and POUND-FOOLISH (PNF), expressed in the SAM, encode DNA-binding proteins that are essential for specifying floral primordia and establishing early internode patterning events during inflorescence development. Biochemical studies show that PNY associates with the knotted1-like homeobox (KNOX) proteins, SHOOTMERISTEMLESS (STM) and BREVIPEDICELLUS (BP). PNY-BP heterodimers are essential for establishing early internode patterning events, while PNY-STM heterodimers are critical for SAM function. In this report, we examined the role of PNY, PNF and STM during development. First, we show that PNF interacts with STM and BP indicating that PNY and PNF are redundant functioning proteins. Inflorescence development, but not vegetative development, is sensitive to the dosage levels of PNY, PNF and STM. Characterization of stm-10, a weak allele in the Columbia ecotype, indicates that STM is also involved in floral specification and internode development. Our examination of the genetic requirements for PNY, PNF and STM demonstrates that these KNOX-BELL heterodimers control floral specification, internode patterning and the maintenance of boundaries between initiating floral primordia and the inflorescence meristem.

Arabidopsis↗
PubMed2002

The complete sequence of the rice (Oryza sativa L.) mitochondrial genome: frequent DNA sequence acquisition and loss during the evolution of flowering plants.

The entire mitochondrial genome of rice (Oryza sativa L.), a monocot plant, has been sequenced. It was found to comprise 490,520 bp, with an average G+C content of 43.8%. Three rRNA genes, 17 tRNA genes and five pseudo tRNA sequences were identified. In addition, eleven ribosomal protein genes and two pseudo ribosomal protein genes were found, which are homologous to 13 of the 16 genes for ribosomal proteins in the mitochondrial genome of the liverwort (Marchantia polymorpha). A greater degree of variation in terms of presence/absence and integrity of genes was observed among the ribosomal protein genes and tRNA genes of rice, Arabidopsis and sugar beet. Transcription and post-transcriptional modification (RNA editing) in the rice mitochondrial sequence were also examined. In all, 491 Cs in the genomic DNA were converted to Ts in cDNA. The frequency of RNA editing differed markedly depending upon the ORF considered. Sequences derived from plastid and nuclear genomes make up 6.3% and 13.4% of the mitochondrial genome, respectively. The degree of conservation of plastid sequences in the mitochondrial genome ranged from 61% to 100%, suggesting that sequence migration has occurred very frequently. Three plastid DNA fragments that were incorporated into the mitochondrial genome were subsequently transferred to the nuclear genome. Nineteen fragments that were similar to transposon or retrotransposon sequences, but different from those found in the mitochondrial genomes of dicots, were identified. The results indicate frequent and independent DNA sequence flow to and from the mitochondrial genome during the evolution of flowering plants, and this may account for the range of genetic variation observed between the mitochondrial genomes of higher plants.

Biological Evolution↗
PubMed2005

Genomic variability of prune dwarf virus as affected by agricultural practice.

Twelve new sequences of the coat protein gene of Prune dwarf virus (PDV) variants, obtained from almond trees, are presented. Comparison with previously reported sequences of the same region, obtained from other hosts (plum, cherry and peach) revealed not only the existence of a wider range of variants of PDV than formerly predicted, but also the frequent presence of a mixture of variants in each sample. In spite of the heterogeneity found in almond, the amino acid composition of the domain at the N terminus of the coat protein maintained the potential to form an amphipathic helix, and hence the capacity to serve the previously suggested function of binding the viral RNA during particle formation. Except for synonymous substitutions, measures of nucleotide diversity calculated for the two groups, respectively 13 sequences from almond and 14 sequences from other hosts, were found to be significantly different, with the almond group showing a much higher variability. Analysis of the dendrogram constructed based in all 27 PDV CP sequences did not reveal host specificity, in agreement with previous findings. However, a clear divergence between almond and other hosts sequences could be found. It is discussed that the observed differences between almond and other hosts variants may derive from differences in agricultural practices.

Agriculture↗
PubMed2005

Calcium changes and the response to methyl jasmonate in rice lodicules during anthesis.

Potassium pyroantimonate precipitation was used to locate loosely bound calcium in rice (Oryza sativa L.) lodicules before and after anthesis, and flowering of panicles was accelerated by treatment with methyl jasmonate. From 1 day to 4 h before anthesis, the number of calcium precipitates in the cell walls and vacuole membranes decreased gradually, whereas they increased remarkably in the cytoplasm and nucleolus. At the beginning of anthesis, the number of calcium granules in lodicules reduced sharply, but there was a large accumulation of flocculent precipitates in the vacuoles. After anthesis, the flocculent precipitates decreased in number until they disappeared, whereas the granular precipitates started to accumulate once again. The rice florets treated with 2 mM methyl jasmonate were induced to open within 10-30 min and they then closed 0.5-1 h later. The nucleolus, cytoplasm, and vacuole membrane of the lodicule cells contained many calcium granules during flowering, although the cell walls lacked calcium. At 1 h after treatment, the number of calcium granules had decreased, while flocculent precipitates were regularly observed in the nondegenerated cells. At 6 h after treatment, calcium grains started to reappear in the cell walls. These changes in calcium precipitates before and after anthesis indicate that the opening and closing of florets correlates with the calcium level in lodicule cells. In addition, excised panicles, with florets judged to be nearing anthesis, were soaked in 2-200 mM EGTA solution for 2 min after treatment with 2 mM methyl jasmonate. The results indicate that EGTA had an antagonistic effect on the methyl jasmonate-induced floret opening in rice.

Acetates↗
PubMed2005

Effects of hypergravity conditions on elongation growth and lignin formation in the inflorescence stem of Arabidopsis thaliana.

The effects of hypergravity on elongation growth and lignin deposition in secondary cell walls of the Arabidopsis thaliana (L.) Heynh. inflorescence stem were examined in plants grown for 3 days after exposure to hypergravity in the direction from shoot to root at 300 g for 24 h. The content of acetylbromide-extractable lignins in a secondary cell wall fraction prepared by enzyme digestion of inflorescence stem segments removing primary cell wall components was significantly increased by the hypergravity stimulus. Xylem vessels, particularly in a region closer to the base of the inflorescence stem, increased in number. Gadolinium chloride at 0.1 mM, a blocker of mechanoreceptors, partially suppressed the effect of hypergravity on lignin deposition in the secondary cell wall fraction. These results suggest that mechanoreceptors are responsible for hypergravity-induced lignin deposition in secondary cell walls in A. thaliana inflorescence stems.

Arabidopsis↗
PubMed2005

Production of pectinase from deseeded sunflower head by Aspergillus niger in submerged and solid-state conditions.

Studies were carried out on the production of pectinases using deseeded sunflower head by Aspergillus niger DMF 27 and DMF 45 in submerged fermentation (SmF) and solid-state fermentation (SSF). Higher titres of endo- and exo-pectinases were observed when medium was supplemented with carbon (4% glucose for SmF and 6% sucrose for SSF) and nitrogen (ammonium sulphate, 0.3% for both SmF and SSF) sources. Green gram husk proved to be relatively a better supplement to attain higher yield of endo-pectinase (11.7 U/g) and exo-pectinase (30.0 U/g) in solid-state conditions. Maximum production of endo-pectinase (19.8 U/g) and exo-pectinase (45.9 U/g) by DMF 45 were recorded in SSF when compared to endo-pectinase (18.9 U/ml) and exo-pectinase (30.3 U/ml) by DMF 27 in SmF under optimum process conditions.

Aspergillus niger↗
PubMed2005

Optimization of process for the production of fungal pectinases from deseeded sunflower head in submerged and solid-state conditions.

Pectinase production studies were carried out in submerged and solid-state conditions from deseeded sunflower head employing Aspergillus niger. The two potential strains of A. niger, DMF 27 for submerged and DMF 45 for solid-state were isolated by multi-step screening technique based on coefficient of pectolysis and capability of pectinase production. Process variables such as size of inoculum, pH, temperature, particle size and moisture content were optimized with an aim to achieve the maximum production of pectinases. The increased level of pectinase production was recorded at pH 5.0 and temperature 34 degrees C in submerged and solid-state conditions. The optimum inoculum size was 1x10(5)ml(-1) for submerged and 1x10(7)g(-1) for solid-state conditions. Five hundred micrometer particle size and 65% moisture content of the substrate were optimum for the maximum production of pectinases in solid-state condition. Under optimum conditions, maximum production of exo-pectinase was 34.2U/g in SSF and endo-pectinase was 12.6U/ml in SmF.

Aspergillus niger↗