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1.
Int J Mol Sci ; 22(14)2021 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-34299238

RESUMO

This study focused on the biological evaluation and chemical characterization of Geranium pyrenaicum Burm. f. Different solvent extracts (hexane, ethyl acetate, methanol, and water extracts) were prepared. The phytochemical profile, antioxidant, and enzyme inhibitory activity were investigated. Cytotoxicity was assessed using VERO, FaDu, HeLa and RKO cells. The antiviral activity was carried out against HSV-1 (Herpes simplex virus 1) propagated in VERO cell line. The aqueous extract, possessing high phenolic content (170.50 mg gallic acid equivalent/g extract), showed the highest reducing capacity (613.27 and 364.10 mg Trolox equivalent/g extract, for cupric reducing antioxidant capacity and ferric reducing antioxidant power, respectively), radical scavenging potential (469.82 mg Trolox equivalent/g extract, against 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)), metal chelating ability (52.39 mg ethylenediaminetetraacetic acid equivalent/g extract) and total antioxidant capacity (3.15 mmol Trolox equivalent/g extract). Liquid chromatography-electrospray ionization-quadrupole time-of-flight-mass spectrometry (LC-ESI-QTOF-MS/MS) alloved to tentatively identify a total of 56 compounds in the extracts, including ellagitannins, gallic acid and galloyl derivatives amongst others. The ethyl acetate extracts substantially depressed cholinesterase enzymes (4.49 and 12.26 mg galantamine equivalent/g extract against AChE and BChE, respectively) and α-amylase enzyme (1.04 mmol acarbose equivalent/g extract). On the other hand, the methanolic extract inhibited tyrosinase (121.42 mg kojic acid equivalent/g extract) and α-glucosidase (2.39 mmol acarbose equivalent/g extract) activities. The highest selectivity towards all cancer cell lines (SI 4.5-10.8) was observed with aqueous extract with the FaDu cells being the most sensitive (CC50 40.22 µg/mL). It can be concluded that the presence of certain bioactive antiviral molecules may be related to the high anti HSV-1 activity of the methanolic extract. This work has generated vital scientific data on this medicinal plant, which is a prospective candidate for the creation of innovative phyto-pharmaceuticals.


Assuntos
Geranium/metabolismo , Extratos Vegetais/química , Animais , Antioxidantes , Antivirais , Linhagem Celular , Cromatografia Líquida de Alta Pressão/métodos , Flavonoides/análise , Humanos , Fenóis/análise , Compostos Fitoquímicos/química , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Plantas Medicinais/química , Estudos Prospectivos , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrometria de Massas em Tandem/métodos
2.
Protoplasma ; 257(2): 501-523, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31792604

RESUMO

Nectar is a major floral reward offered to pollinators by plants. In dichogamous plant species, differences in nectar production across sexual phases often occur, but both the male- and female-phase flowers have to attract pollinators to achieve effective pollination. Nectar-producing structures, i.e. floral nectaries, are a key component of floral organisation and architecture, and the knowledge of their structure and function contributes to better understanding of the plant-pollinator interactions. In the present study, we investigated the morphology and structure of nectaries and the nectar production pattern in two protandrous species Geranium macrorrhizum and G. phaeum. The flowers of the studied species have been shown to exhibit varied availability of nectar for insect visitors. Their nectaries differ in the shape, size and thickness. The other differences include the localisation of the stomatal field, the size and number of nectarostomata, the presence of non-glandular and glandular trichomes, the presence of tannin idioblasts, the mode of secretion and the occurrence of plastids functioning probably as autophagosomes and autolysosomes, whose presence in nectary cells has been described for the first time. The flowers of the studied species started nectar secretion in the non-receptive phase before pollen presentation and nectar was produced throughout both sexual phases. The nectar production was gender biased towards the female phase in the nectar amount, nectar sugar concentration and total sugar secreted in the nectar. We postulate that the nectar production patterns in G. phaeum and G. macrorrhizum might have evolved as a response to pollinators' pressure.


Assuntos
Geranium/anatomia & histologia , Geranium/metabolismo , Néctar de Plantas/biossíntese , Pólen/anatomia & histologia , Pólen/metabolismo
3.
Chem Biodivers ; 17(2): e1900544, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31840372

RESUMO

Geranium species are widely used in traditional medicine of Balkan. The aim of this work was to investigate and compare chemical composition of volatile fractions obtained by hydrodistillation from aerial parts of G. macrorrhizum, G. phaeum, G. sanguineum, G. robertianum, G. palustre, G. pyrenaicum, G. columbinum and G. lucidum as well as from underground parts of G. macrorrhizum and G. phaeum, originated from Vlasina plateau in South Eastern Serbia. The volatiles were analyzed using GC/MS and GC-FID. G. palustre volatiles have been studied for the first time with ß-selinene (18.6 %) as a characteristic compound. The cluster analysis revealed separation of volatiles into two main groups. Volatile fractions of G. macrorrhizum were separated from all other samples due to high sesquiterpene content (92.3 % in aerial and 94.6 % in underground parts). The volatile fractions of other samples were mainly composed of sesquiterpenes (10.8-61.8 %), diterpenes (12.9-43.0 %) and fatty acids and their derivatives (6.6-21.6 %) with the exception of volatile fraction of G. phaeum underground parts which was dominated only by fatty acids and their derivatives (76.6 %). The results presented in this article contribute to the knowledge on the chemistry of this genus and advances the knowledge on flora of southeast Serbia.


Assuntos
Geranium/química , Compostos Orgânicos Voláteis/química , Análise por Conglomerados , Cromatografia Gasosa-Espectrometria de Massas , Geranium/metabolismo , Componentes Aéreos da Planta/química , Componentes Aéreos da Planta/metabolismo , Sérvia , Sesquiterpenos/química , Sesquiterpenos/isolamento & purificação , Compostos Orgânicos Voláteis/análise
4.
FEBS Lett ; 593(16): 2235-2249, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31210363

RESUMO

This study aimed to explore the noncoding RNAs, which have emerged as key regulatory molecules in biological processes, in rose-scented geranium. We analyzed RNA-seq data revealing 26 784 long noncoding RNAs (lncRNAs) and 871 miRNAs in rose-scented geranium. A total of 466 lncRNAs were annotated using different plant lncRNA public databases. Furthermore, 372 lncRNAs and 99 miRNAs were detected that target terpene and tartarate biosynthetic pathways. An interactome, comprising of lncRNAs, miRNAs, and mRNAs, was constructed that represents a noncoding RNA regulatory network of the target mRNAs. Real-time quantitative PCR expression validation was done for selected lncRNAs involved in the regulation of terpene and tartaric acid pathways. This study provides the first insights into the regulatory functioning of noncoding RNAs in rose-scented geranium.


Assuntos
Vias Biossintéticas , Perfilação da Expressão Gênica/métodos , Geranium/metabolismo , MicroRNAs/genética , RNA Longo não Codificante/genética , Regulação da Expressão Gênica de Plantas , Redes Reguladoras de Genes , Geranium/genética , Anotação de Sequência Molecular , Reação em Cadeia da Polimerase em Tempo Real , Análise de Sequência de RNA , Tartaratos/metabolismo , Terpenos/metabolismo
5.
BMC Plant Biol ; 19(1): 58, 2019 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-30727963

RESUMO

BACKGROUND: Plants grow in multi-species communities rather than monocultures. Yet most studies on the emission of volatile organic compounds (VOCs) from plants in response to insect herbivore feeding focus on one plant species. Whether the presence and identity of neighboring plants or plant community attributes, such as plant species richness and plant species composition, affect the herbivore-induced VOC emission of a focal plant is poorly understood. METHODS: We established experimental plant communities in pots in the greenhouse where the focal plant species, red clover (Trifolium pratense), was grown in monoculture, in a two species mixture together with Geranium pratense or Dactylis glomerata, or in a mixture of all three species. We measured VOC emission of the focal plant and the entire plant community, with and without herbivory of Spodoptera littoralis caterpillars caged on one red clover individual within the communities. RESULTS: Herbivory increased VOC emission from red clover, and increasing plant species richness changed emissions of red clover and also from the entire plant community. Neighbor identity strongly affected red clover emission, with highest emission rates for plants growing together with D. glomerata. CONCLUSION: The results from this study indicate that the blend of VOCs perceived by host searching insects can be affected by plant-plant interactions.


Assuntos
Ecossistema , Plantas/metabolismo , Compostos Orgânicos Voláteis/metabolismo , Animais , Dactylis/metabolismo , Geranium/metabolismo , Herbivoria , Larva , Spodoptera , Trifolium/metabolismo
6.
Planta ; 248(6): 1515-1523, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30140978

RESUMO

MAIN CONCLUSION: LAESI-MSI, an innovative high-throughput technique holds a unique potential for untargeted detection, profiling and spatial localization of metabolites from intact plant samples without need for extraction or extensive sample preparation. Our understanding of chemical diversity in biological samples has greatly improved through recent advances in mass spectrometry (MS). MS-based-imaging (MSI) techniques have further enhanced this by providing spatial information on the distribution of metabolites and their relative abundance. This study aims to employ laser-ablation electrospray ionization (LAESI) MSI as a tool to profile and compare the root metabolome of two pairs of native and range-expanding plant species. It has been proposed that successful range-expanding plant species, like introduced exotic invaders, have a novel, or a more diverse secondary chemistry. Although some tests have been made using aboveground plant materials, tests using root materials are rare. We tested the hypothesis that range-expanding plants possess more diverse root chemistries than native plant species. To examine the root chemistry of the selected plant species, LAESI-MSI was performed in positive ion mode and data were acquired in a mass range of m/z 50-1200 with a spatial resolution of 100 µm. The acquired data were analyzed using in-house scripts, and differences in the spatial profiles were studied for discriminatory mass features. The results revealed clear differences in the metabolite profiles amongst and within both pairs of congeneric plant species, in the form of distinct metabolic fingerprints. The use of ambient conditions and the fact that no sample preparation was required, established LAESI-MSI as an ideal technique for untargeted metabolomics and for direct correlation of the acquired data to the underlying metabolomic complexity present in intact plant samples.


Assuntos
Centaurea/metabolismo , Geranium/metabolismo , Metaboloma , Metabolômica , Espectrometria de Massas por Ionização por Electrospray , Raízes de Plantas/metabolismo
7.
Mol Biol Rep ; 45(3): 315-326, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29546478

RESUMO

Rose-scented geranium (Pelargonium sp.) is widely known as aromatic and medicinal herb, accumulating specialized metabolites of high economic importance, such as essential oils, ascorbic acid, and tartaric acid. Ascorbic acid and tartaric acid are multifunctional metabolites of human value to be used as vital antioxidants and flavor enhancing agents in food products. No information is available related to the structural and functional properties of the enzymes involved in ascorbic acid and tartaric acid biosynthesis in rose-scented geranium. In the present study, transcriptome mining was done to identify full-length genes, followed by their bioinformatic and molecular modeling investigations and understanding of in silico structural and functional properties of these enzymes. Evolutionary conserved domains were identified in the pathway enzymes. In silico physicochemical characterization of the catalytic enzymes revealed isoelectric point (pI), instability index, aliphatic index, and grand average hydropathy (GRAVY) values of the enzymes. Secondary structural prediction revealed abundant proportion of alpha helix and random coil confirmations in the pathway enzymes. Three-dimensional homology models were developed for these enzymes. The predicted structures showed significant structural similarity with their respective templates in root mean square deviation analysis. Ramachandran plot analysis of the modeled enzymes revealed that more than 84% of the amino acid residues were within the favored regions. Further, functionally important residues were identified corresponding to catalytic sites located in the enzymes. To, our best knowledge, this is the first report which provides a foundation on functional annotation and structural determination of ascorbic acid and tartaric acid pathway enzymes in rose-scanted geranium.


Assuntos
Ácido Ascórbico/biossíntese , Geranium/genética , Geranium/metabolismo , Tartaratos/metabolismo , Antioxidantes/metabolismo , Ácido Ascórbico/genética , Biologia Computacional/métodos , Simulação por Computador , Bases de Dados Genéticas , Óleos Voláteis/metabolismo , Filogenia , Óleos Vegetais/metabolismo , Homologia Estrutural de Proteína , Transcriptoma/genética
8.
Environ Geochem Health ; 40(4): 1355-1375, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29299858

RESUMO

Germanium is considered to be a non-essential element; however, little is still known about its significance for living organisms. It exerts prophylactic and therapeutic effects in the treatment of serious diseases such as cancer, HIV infection, and others. Germanium does not exhibit acute toxicity, but, as it tends to accumulate in various organs and tissues, undesirable and even dangerous side effects have been reported after prolonged and/or high dosage application. In general, inorganic compounds of germanium are more toxic than its organic compounds. Further studies should be performed to elucidate the exact molecular mechanism of germanium action, to determine the safe and effective dose of germanium via curative/mineral waters, and to understand the applications and benefits of using germanium-enriched waters in balneotherapy. The geochemistry of curative (cold CO2-rich, thermal) waters from spas in the Sudetes (Poland) was clarified in terms of components and mineral phases which might govern germanium. Germanium and silicon in thermal (above 20 °C) waters presumably result from the solubility of silicates in crystalline (granites, gneisses) aquifer rocks and might be controlled by neo-formed quartz. The cold CO2-rich waters revealed a significant diversity of aqueous chemistry and relationships of germanium with iron, silicon, or arsenic. Locally, both in sedimentary (sandstones) and metamorphic (gneisses) aquifer rocks, primary (silicates) and/or secondary (oxides) iron-containing minerals likely release germanium into solution. In the CO2-rich waters of the western part of the Klodzko Region, germanium distinctly correlates with arsenic. It is hypothesized that both elements are co-sourced from crystalline basement and/or migration of substances of post-magmatic origin along deep-seated dislocations related to the seismically active Porící-Hronov fault zone. This area was proposed as the most prospective one for finding waters rich in germanium in the Sudetes.


Assuntos
Balneologia , Fenômenos Geológicos , Geranium , Estâncias para Tratamento de Saúde , Hidrologia , Águas Minerais/análise , Dióxido de Carbono/análise , Geranium/metabolismo , Humanos , Polônia , Silício/análise , Solubilidade
9.
Plant Biol (Stuttg) ; 19(6): 896-903, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28742938

RESUMO

In gynodioecious plants, females are expected to produce more or better seeds than hermaphrodites in order to be maintained within the same population. Even though rarely measured, higher seed production can be achieved through differences in physiology. In this work, we measured sexual dimorphism in several physiological traits in the gynodioecious plant Geranium sylvaticum. Photosynthetic rate, stomatal conductance, transpiration rate, WUE and isotopic signatures were measured in plants growing in two habitats differing in light availability. Females have been reported to produce more seeds than hermaphrodites. However, we did not observe any significant difference in seed output between the sexes in these experimental populations. Similarly, the sexes did not differ in any physiological trait measured. Seed production was strongly limited by light availability. Likewise, differences between plants growing in full light versus low light were detected in most physiological parameters measured. Our results show that the sexes in G. sylvaticum do not show any evidence of sexual dimorphism in physiology, which concurred with a lack of sexual differences in seed output.


Assuntos
Geranium/fisiologia , Fotossíntese/fisiologia , Caracteres Sexuais , Flores/fisiologia , Geranium/metabolismo , Luz , Transpiração Vegetal/fisiologia , Reprodução/fisiologia , Sementes/crescimento & desenvolvimento
10.
BMC Genomics ; 18(1): 74, 2017 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-28086783

RESUMO

BACKGROUND: Rose-scented geranium (Pelargonium sp.) is a perennial herb that produces a high value essential oil of fragrant significance due to the characteristic compositional blend of rose-oxide and acyclic monoterpenoids in foliage. Recently, the plant has also been shown to produce tartaric acid in leaf tissues. Rose-scented geranium represents top-tier cash crop in terms of economic returns and significance of the plant and plant products. However, there has hardly been any study on its metabolism and functional genomics, nor any genomic expression dataset resource is available in public domain. Therefore, to begin the gains in molecular understanding of specialized metabolic pathways of the plant, de novo sequencing of rose-scented geranium leaf transcriptome, transcript assembly, annotation, expression profiling as well as their validation were carried out. RESULTS: De novo transcriptome analysis resulted a total of 78,943 unique contigs (average length: 623 bp, and N50 length: 752 bp) from 15.44 million high quality raw reads. In silico functional annotation led to the identification of several putative genes representing terpene, ascorbic acid and tartaric acid biosynthetic pathways, hormone metabolism, and transcription factors. Additionally, a total of 6,040 simple sequence repeat (SSR) motifs were identified in 6.8% of the expressed transcripts. The highest frequency of SSR was of tri-nucleotides (50%). Further, transcriptome assembly was validated for randomly selected putative genes by standard PCR-based approach. In silico expression profile of assembled contigs were validated by real-time PCR analysis of selected transcripts. CONCLUSION: Being the first report on transcriptome analysis of rose-scented geranium the data sets and the leads and directions reflected in this investigation will serve as a foundation for pursuing and understanding molecular aspects of its biology, and specialized metabolic pathways, metabolic engineering, genetic diversity as well as molecular breeding.


Assuntos
Perfilação da Expressão Gênica , Geranium/genética , Geranium/metabolismo , Tartaratos/metabolismo , Terpenos/metabolismo , Transcriptoma , Análise por Conglomerados , Biologia Computacional/métodos , Ontologia Genética , Sequenciamento de Nucleotídeos em Larga Escala , Redes e Vias Metabólicas , Repetições de Microssatélites , Anotação de Sequência Molecular , Fenótipo , Reprodutibilidade dos Testes
11.
Plant Physiol Biochem ; 89: 53-63, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25698666

RESUMO

The overexpression of dihydroxyacetone synthase (DAS) and dihydroxyacetone kinase (DAK) from methylotrophic yeasts in chloroplasts created a photosynthetic formaldehyde (HCHO)-assimilation pathway (DAS/DAK pathway) in transgenic tobacco. Geranium has abilities to absorb and metabolize HCHO. Results of this study showed that the installed DAS/DAK pathway functioning in chloroplasts greatly enhanced the role of the Calvin cycle in transgenic geranium under high concentrations of gaseous HCHO stress. Consequently, the yield of sugars from HCHO-assimilation increased approximately 6-fold in transgenic geranium leaves, and concomitantly, the role of three original HCHO metabolic pathways reduced, leading to a significant decrease in formic acid, citrate and glycine production from HCHO metabolism. Although the role of three metabolic pathways reduced in transgenic plants under high concentrations of gaseous HCHO stress, the installed DAS/DAK pathway could still function together with the original HCHO metabolic pathways. Consequently, the gaseous HCHO-resistance of transgenic plants was significantly improved, and the generation of H2O2 in the transgenic geranium leaves was significantly less than that in the wild type (WT) leaves. Under environmental-polluted gaseous HCHO stress for a long duration, the stomata conductance of transgenic plants remained approximately 2-fold higher than that of the WT, thereby increasing its ability to purify gaseous HCHO polluted environment.


Assuntos
Adaptação Fisiológica/genética , Aldeído-Cetona Transferases/genética , Poluentes Ambientais/metabolismo , Formaldeído/metabolismo , Geranium/genética , Fosfotransferases (Aceptor do Grupo Álcool)/genética , Plantas Geneticamente Modificadas/genética , Aldeído-Cetona Transferases/metabolismo , Biodegradação Ambiental , Cloroplastos/metabolismo , Gases/metabolismo , Expressão Gênica , Genes Fúngicos , Geranium/metabolismo , Peróxido de Hidrogênio/metabolismo , Redes e Vias Metabólicas/genética , Fosfotransferases (Aceptor do Grupo Álcool)/metabolismo , Fotossíntese/genética , Folhas de Planta/metabolismo , Estômatos de Plantas/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Estresse Fisiológico , Tabaco/genética , Leveduras/genética
12.
Chem Biodivers ; 11(4): 542-50, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24706624

RESUMO

4,5- and 1,10-Epoxygermacrones were isolated from the essential oil of aerial parts of Geranium macrorrhizum L. (Geraniaceae). The structures of the epoxy derivatives were deduced from their 1D- and 2D-NMR spectra, molecular modeling, and confirmed by synthesis starting from germacrone. The epoxy compounds were screened for their antimicrobial activities by a microdilution assay, which revealed high activities of both compounds against Bacillus subtilis (minimum inhibitory concentrations (M/Cs) determined were 4.3 and 43 nmol/ml for 1,10- and 4,5-epoxygermacrone, resp.) and Pseudomonas aeruginosa (0.043 and 0.855 µmol/ml for 1,10- and 4,5-epoxygermacrone, resp.). The discovery and observed activity of the two epoxides fills the gap in our knowledge of the active principles in this highly renowned ethnomedicinal plant species.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Geranium/química , Sesquiterpenos de Germacrano/química , Bacillus subtilis/efeitos dos fármacos , Técnicas de Química Sintética , Compostos de Epóxi/química , Compostos de Epóxi/farmacologia , Geranium/metabolismo , Espectroscopia de Ressonância Magnética , Testes de Sensibilidade Microbiana , Estrutura Molecular , Óleos Voláteis/química , Plantas Medicinais/química , Pseudomonas aeruginosa/efeitos dos fármacos , Sesquiterpenos de Germacrano/síntese química , Sesquiterpenos de Germacrano/farmacologia , Relação Estrutura-Atividade
13.
Phytochemistry ; 95: 408-20, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24050514

RESUMO

Geranium sylvaticum is a common herbaceous plant in Fennoscandia, which has a unique phenolic composition. Ellagitannins, proanthocyanidins, galloylglucoses, gallotannins, galloyl quinic acids and flavonoids possess variable distribution in its different organs. These phenolic compounds are thought to have an important role in plant-herbivore interactions. The aim of this study was to quantify these different water-soluble phenolic compounds and measure the biological activity of the eight organs of G. sylvaticum. Compounds were characterized and quantified using HPLC-DAD/MS, in addition, total proanthocyanidins were determined by BuOH-HCl assay and total phenolics by the Folin-Ciocalteau method. Two in vitro biological activity measurements were used: the prooxidant activity was measured by the browning assay and antioxidant activity by the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay. Organ extracts were fractionated using column chromatography on Sephadex LH-20 and the activities of fractions was similarly measured to evaluate which polyphenol groups contributed the most to the biological activity of each organ. The data on the activity of fractions were examined by multivariate data analysis. The water-soluble extracts of leaves and pistils, which contained over 30% of the dry weight as ellagitannins, showed the highest pro-oxidant activity among the organ extracts. Fraction analysis revealed that flavonoids and galloyl quinic acids also exhibited high pro-oxidant activity. In contrast, the most antioxidant active organ extracts were those of the main roots and hairy roots that contained high amounts of proanthocyanidins in addition to ellagitannins. Analysis of the fractions showed that especially ellagitannins and galloyl quinic acids have high antioxidant activity. We conclude that G. sylvaticum allocates a significant amount of tannins in those plant parts that are important to the fitness of the plant and susceptible to natural enemies, i.e. pistil and leaf tannins protect against insect herbivores and root tannins against soil pathogens.


Assuntos
Flavonoides/metabolismo , Geranium/metabolismo , Taninos Hidrolisáveis/metabolismo , Fenóis/metabolismo , Doenças das Plantas , Estruturas Vegetais/metabolismo , Taninos/metabolismo , Antioxidantes/farmacologia , Resistência à Doença , Herbivoria , Hidroxibenzoatos/metabolismo , Oxidantes/farmacologia , Polifenóis/metabolismo
14.
Phytochemistry ; 95: 394-407, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23790750

RESUMO

A combination of high-resolution mass spectrometry and modern HPLC column technology, assisted by diode array detection, was used for accurate characterization of water-soluble polyphenolic compounds in the pistils, stamens, petals, sepals, stems, leaves, roots and seeds of Geranium sylvaticum. The organs contained a large variety of polyphenols, five types of tannins (ellagitannins, proanthocyanidins, gallotannins, galloyl glucoses and galloyl quinic acids) as well as flavonoids and simple phenolic acids. In all, 59 compounds were identified. Geraniin and other ellagitannins dominated in all the green photosynthetic organs. The other organs seem to produce distinctive polyphenol groups: pistils accumulated gallotannins; petals acetylglucose derivatives of galloylglucoses; stamens kaempferol glycosides, and seeds and roots accumulated proanthocyanidins. The intra-plant distribution of the different polyphenol groups may reflect the different functions and importance of various types of tannins as the defensive chemicals against herbivory.


Assuntos
Flavonoides/metabolismo , Geranium/metabolismo , Taninos Hidrolisáveis/metabolismo , Fenóis/metabolismo , Doenças das Plantas , Estruturas Vegetais/metabolismo , Taninos/metabolismo , Resistência à Doença , Glucosídeos/metabolismo , Glicosídeos/metabolismo , Herbivoria , Hidroxibenzoatos/metabolismo , Polifenóis/metabolismo
15.
PLoS One ; 8(4): e62575, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23614053

RESUMO

Many zoophilous plants attract their pollinators by offering nectar as a reward. In gynodioecious plants (i.e. populations are composed of female and hermaphrodite individuals) nectar production has been repeatedly reported to be larger in hermaphrodite compared to female flowers even though nectar production across the different floral phases in dichogamous plants (i.e. plants with time separation of pollen dispersal and stigma receptivity) has rarely been examined. In this study, sugar production in nectar standing crop and secretion rate were investigated in Geranium sylvaticum, a gynodioecious plant species with protandry (i.e. with hermaphrodite flowers releasing their pollen before the stigma is receptive). We found that flowers from hermaphrodites produced more nectar than female flowers in terms of total nectar sugar content. In addition, differences in nectar production among floral phases were found in hermaphrodite flowers but not in female flowers. In hermaphrodite flowers, maximum sugar content coincided with pollen presentation and declined slightly towards the female phase, indicating nectar reabsorption, whereas in female flowers sugar content did not differ between the floral phases. These differences in floral reward are discussed in relation to visitation patterns by pollinators and seed production in this species.


Assuntos
Carboidratos/biossíntese , Flores/metabolismo , Geranium/metabolismo , Néctar de Plantas/metabolismo , Animais , Flores/crescimento & desenvolvimento , Geranium/crescimento & desenvolvimento , Organismos Hermafroditas/crescimento & desenvolvimento , Organismos Hermafroditas/metabolismo , Polinização , Recompensa
16.
Nat Prod Commun ; 5(6): 899-902, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20614819

RESUMO

An investigation was made of the effects on endogenous antioxidant enzyme activities and H2O2-induced lipid peroxidation inhibition in human red blood cells of the crude MeOH extract and its EtOAc, n-BuOH, and H2O sub-extracts obtained from aerial parts of Geranium psilostemon Ledeb., as well as compounds isolated from the most active EtOAc extract. Gallic acid (1), methyl gallate (2), pusilagin (3), 1,3,6-tri-O-galloyl-beta-glucopyranoside (4), 1,2,3,4,6-penta-O-galloyl-beta-glucopyranoside (5), kaempferol (6), quercetin (7), kaempferol 7-O-alpha-rhamnopyranoside (8), and quercetin 7-O-alpha-rhamnopyranoside (9) were isolated from the aerial parts of the title plant, and their structures identified from spectroscopic (UV, 1D- and 2D- NMR) and spectrometric (TOF-MS) data. All extracts and isolated compounds inhibited H2O2-induced lipid peroxidation and also enhanced the activity of superoxide dismutase (SOD) and catalase (CAT).


Assuntos
Antioxidantes/química , Antioxidantes/metabolismo , Geranium/química , Geranium/metabolismo , Eritrócitos/efeitos dos fármacos , Eritrócitos/metabolismo , Humanos , Peróxido de Hidrogênio , Peroxidação de Lipídeos , Componentes Aéreos da Planta/química
17.
Biotechnol Lett ; 32(10): 1541-8, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20549541

RESUMO

3-Hexulose-6-phosphate synthase (HPS) and 6-phosphate-3-hexuloisomerase (PHI) are two key enzymes in the formaldehyde (HCHO) assimilation pathway in methylotrophs. The HPS/PHI fusion protein, encoded by the chimeric gene of hps and phi from Mycobacterium gastri MB19, possesses both HPS and PHI activities in an Escherichia coli transformant. Overexpression of the fusion protein in chloroplasts of geranium (Pelargonium sp. Frensham) created a photosynthetic HCHO assimilation pathway according to (13)C-NMR analysis. The transgenic plants exhibited an enhanced ability in HCHO-uptake and [(14)C]HCHO-assimilation. Moreover, the transgenic plants showed greater HCHO-resistance and stronger capacity in purification of the HCHO-polluted air. Therefore, the use of the single chimeric gene may not only greatly simplify the transformation procedure but also improve the efficiency of phytoremediating HCHO in ornamental plants.


Assuntos
Aldeído Liases/metabolismo , Aldose-Cetose Isomerases/metabolismo , Cloroplastos/metabolismo , Formaldeído/metabolismo , Geranium/metabolismo , Mycobacterium/enzimologia , Aldeído Liases/genética , Aldose-Cetose Isomerases/genética , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Isótopos de Carbono/metabolismo , Cloroplastos/genética , Escherichia coli/genética , Escherichia coli/metabolismo , Geranium/genética , Espectroscopia de Ressonância Magnética , Mycobacterium/genética , Fotossíntese , Proteínas Recombinantes de Fusão/biossíntese , Proteínas Recombinantes de Fusão/genética
18.
J Plant Physiol ; 166(5): 467-76, 2009 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-18778872

RESUMO

Geranium plants are an important part of urban green areas but suffer from drought, especially when grown in containers with a limited volume of medium. In this experiment, we examined the response of potted geraniums to different irrigation levels. Geranium (Pelargoniumxhortorum L.) seedlings were grown in a growth chamber and exposed to three irrigation treatments, whereby the plants were irrigated to container capacity (control), 60% of the control (moderate deficit irrigation, MDI), or 40% of the control (severe deficit irrigation, SDI). Deficit irrigation was maintained for 2 months, and then all the plants were exposed to a recovery period of 112 month. Exposure to drought induced a decrease in shoot dry weight and leaf area and an increase in the root/shoot ratio. Height and plant width were significantly inhibited by the SDI, while flower color parameters were not affected by deficit treatment. The number of wilting and yellow leaves increased, coinciding with the increase in the number of inflorescences and open flowers. Deficit irrigation led to a leaf water potential of about -0.8MPa at midday, which could have caused an important decrease in stomatal conductance, affecting the photosynthetic rate (Pn). Chlorophyll fluorescence (Fvm) values of 0.80 in all treatments throughout the experiment demonstrate the lack of drought-induced damage to PSII photochemistry. Pressure-volume analysis revealed low osmotic adjustment values of 0.2MPa in the SDI treatment, accompanied by increases in the bulk tissue elastic modulus (epsilon, wall rigidity) and resulting in turgor loss at lower leaf water potential values (-1.38MPa compared with -1.0MPa for the control). Leaf water potential values throughout the experiment below those for Psitlp were not found at any sampling time. By the end of the recovery period, the leaf water potential, stomatal conductance and net photosynthesis had recovered. We infer from these results that moderate deficit irrigation in geranium reduced the consumption of water, while maintaining the good overall quality of plants. However, when SDI was applied, a reduction in the number of flowers per plant was observed.


Assuntos
Flores/fisiologia , Gases/metabolismo , Geranium/crescimento & desenvolvimento , Geranium/metabolismo , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Água/metabolismo , Ritmo Circadiano/efeitos dos fármacos , Flores/efeitos dos fármacos , Geranium/efeitos dos fármacos , Folhas de Planta/efeitos dos fármacos , Pressão , Estações do Ano , Estresse Fisiológico/efeitos dos fármacos , Água/farmacologia
19.
Biofizika ; 53(4): 672-8, 2008.
Artigo em Russo | MEDLINE | ID: mdl-18819286

RESUMO

A mathematical model of delayed luminescence was devised. It is based on the description of primary photosynthetic reactions, which takes the donor and acceptor parties of photosystem II and the electrochemical gradient on thylakoid membranes into account. The model was used for the theoretical analysis of the mechanisms of changes in delayed luminescence characteristics, induced by variation potentials.


Assuntos
Geranium/metabolismo , Luminescência , Modelos Biológicos , Complexo de Proteína do Fotossistema II/metabolismo , Folhas de Planta/metabolismo , Tilacoides/metabolismo , Membranas Intracelulares/metabolismo , Fotossíntese/fisiologia
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