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Organic phosphorus (Po) plays an important role in tropical forest nutrition on strongly-weathered soils. However, of its role in Eucalyptus nutrition little is known. For this purpose, soil P forms were determined by NaOH-Na2EDTA extraction and 31P nuclear magnetic resonance spectroscopy (31P NMR) at 10 sites of Eucalyptus plantations in Brazil. The objectives were (1) to determine the amounts and forms of soil Po; (2) to build a structural model of the soil P cycle to provide quantitative estimates of the transformation processes of soil P. Soil P was found to consist of large amounts of Monoesters-P (on average 43.7 mg kg−1) followed by Diesters-P in the form of DNA (on average 4.2 mg kg−1), as well as containing high reserves of Pi species (on average 101.6 mg kg−1 of the ortho-P; 2.7 mg kg−1 of the pyrophosphate). Thestructural model indicated that the P cycle is regulated by clay, soil organic carbon, total P and pH. High total Po concentrations (on average 48 mg kg−1) reveal a high potential of P supply to Eucalyptus trees, in which Diester-P (DNA) would be the main source P for the available P pool. The close interconnection between ortho-P, pyrophosphate, DNA and Monoester-P compounds provides evidence of a strong influence of soil biological activity on the distribution and accumulation of these P compounds and therefore on the availability of P. Thus, these results are relevant to establish soil fertility management strategies for low-fertilizer input Eucalyptus systems in soils with low fertility.

The

The Latin American medicinal plant carqueja got its name from a morphologically similar plant from the Iberian peninsula. The popular name came in general use to indicate all species from the section Caulopterae from the genus Baccharis, which are often difficult to distinguish. Phytochemical studies indicate that the different species from this section contain similar compound classes, especially essential oils, flavonoids and diterpenes, but much variation is encountered in relation to the individual compounds within the species. There are also some indications for the existance of different chemotypes within species. Recovered information from manuscripts, elaborated in the Jesuit missions, and originally authored by the Jesuit friar Pedro de Montenegro around 1710, indicate that carqueja was used by the Guarani indians of Southern Latin America for wound treatment. This traditional use was largely lost and nowadays the plant is mainly indicated for intestinal problems, as a tonic or for treatment of diabetes. It might be possible that this is caused by a confusion with quina, around 1800, which led to the alternative popular name “Quina de Condamine”. The confusion about the identification of individual species persists up to today. In pharmacological studies performed with crude extracts, doubts arise about the species used and its phytochemical composition. Also in medicinal teas different species are used indiscriminantly leading to great differences in phytochemical profile. In this paper information about the phytochemistry, medicinal use, botanical specimens and nomenclature is extensively reviewed and recommendations for further studies and increased reproducibility of pharmacological studies are given.

Metabolomics can be defined as the area of research that strives to obtain complete metabolic fingerprints, to detect differences between them and to provide hypothesis to explain those differences. This area of research is still rapidly developing into a powerful tool in the study of all types of organisms. This chapter focuses on the practical and efficient application of metabolomics. All different aspects of a metabolomic study are discussed, ranging from the initial questions and experimental design to the instrumental methods and data analysis. Keywords: metabolomics; NMR; GC–MS; LC–MS; metabolic fingerprinting

Plants have been used as sources of food, beverages, fibers, or building materials, and also as sources of poisons, drugs, colorants, flavors, fragrances, and insecticides. Many natural products are now produced as specialty chemicals for applications in the food, pharmaceutical, and flavor and fragrance industries. Synthesis is usually directed at certain compounds, which will only lead to improved drugs for already known receptors, whereas natural compounds are much more probable to show totally new modes of action in broad screens. The screening methods for antibiotic and antiviral activities are rather straightforward. The use of isolated organs for studying certain biological activities is decreasing because of the wish to reduce the number of animal experiments. In plants, a large number of compounds is present, encompassing a broad spectrum of polarities. Screening of plant cell cultures for new biologically active compounds is feasible.

The illegal trade in counterfeit and fake drugs is a worldwide multi-billion dollar industry, not only generating enormous economic losses, but health problems for the general population, through direct toxicity, treatment failure and the increased generation of antibiotic resistance. Techniques for high-throughput testing of suspect medicines are needed to face the challenges of the problem. In this study we show that with nuclear magnetic resonance spectroscopy (NMR) drug compliance can be verified in a few minutes, providing data on drug identity, purity and quality without the necessity to develop a specific methodology and using a direct extraction with deuterated solvent. The evaluation of the data is facilitated by similarity calculations and differential NMR spectroscopy. The viability and limitations of this method were assessed, with the application on five different drugs, namely sertraline hydrochloride, alprazolam, vitamin D

Adulteration of essential oils is a common and serious problem. Adequate and fast methods are required to establish the authenticity and purity. GC-MS, 1H and 13C NMR were compared in combination with similarity calculations as well as differential spectroscopy and chromatography for the authentication and determination of purity of vetiver essential oils. In the investigation of eight commercial oils 1H and 13C NMR adequately detected all six adulterants encountered in four of the commercial samples, while GC-MS was not able to detect adulteration with vegetable oils. A great advantage of the combined use of similarity calculation and NMR is that the authenticity can be verified without the need of concomitant measurement of a standard sample. The calculation can be carried out with a registered reference spectrum, in the case of 1H NMR acquired using the same magnetic field, but in the case of 13C NMR the spectrum can be obtained with another magnetic field. 1H NMR has the advantage of high speed, and the results can be obtained within minutes. 13C NMR was found to be superior in its ability to provide unequivocal identification of eventual adulterants, with differential spectroscopy revealing all signals of the adulterants.

Foodborne diseases and antibiotic resistant bacteria have become a serious worldwide public health problem. In this context, this study was carried out to describe the chemical composition and antimicrobial activity of the essential oils from three Brazilian Ocimum species, since essential oils are considered safe. The essential oils were analyzed by GC–MS and the antimicrobial activities were determined by MIC assays against some pathogens. The essential oils from two samples exhibited effective antimicrobial activity against Bacillus cereus 100–200 μgnmL−1. The concentration of the major compound, linalool (from 24.7% to 60.2%), was not the main feature for the antimicrobial activity. The development of a multivariate statistical method based on O2PLS-DA was carried out for the identification of the most effective combination of constituents to describe the efficiency of O. basilicum essential oils as antimicrobial agents against foodborne pathogens.

Baobab seed oil, obtained from the seed kernel of Adansonia digitata from Southern Africa, has experienced an increase in global demand. 1H and 13C NMR was used for the authentication of the baobab oils, allowing for the quantification of the characteristic cyclopropane and cyclopropene fatty acids. Through similarity analysis, differential NMR spectroscopy and multivariate data analysis substantial differences were observed in commercial samples, segregating the oil samples into two groups. The cyclopropane and cyclopropene fatty acids, were absent in one group of the samples, raising the possibility of falsification. Similarity analysis and multivariate data analysis, in which the spectral data were compared with those of fourteen other vegetable oils, indicated a high correlation between the potentially falsified baobab seed oils and soybean oil. A comparison of the phytosterol markers of the oils by differential NMR confirmed the adulteration with soybean oil.

Understanding the role of N-fixing leguminous trees for phosphorus (P) cycling in highly weathered tropical soils is relevant for the conservation of natural forests as well as the sustainable management of agroforests and forest plantations with low P input in the Brazilian Atlantic Forest region. We hypothesized that N-fixing leguminous trees can increase the availability of soil P by exploiting different P sources without causing a depletion of soil organic P due to efficient biogeochemical cycling, but empirical evidence remains scarce. For this purpose, 31P nuclear magnetic resonance spectroscopy (31P NMR) was used for quantifying soil P forms and the Hedley sequential extraction to determine soil P fractions. The studied sites were forestry systems with leguminous trees: mixed forest plantations with different proportions of fast-growing N-fixing leguminous trees; pure plantations, and agroforestry systems with leguminous trees. The results show that all N-fixing leguminous trees and N mineral fertilization positively affected the concentrations of available soil P in relation to the control treatments. There were increases of all P fractions through cycling in all forest sites. 31P NMR spectra clearly identified and quantified that a large amount of phosphomonoesters followed by phosphodiesters in the form of DNA, as well as high reserves of Pi species (ortho-P and pyrophosphate) in the first eleven years of growth at pure plantations, mixed plantations or agroforests. The relations between both ortho-P and DNA with the resin-Pi, NaHCO3-Pi and NaOH-Pi fractions suggest that both analysis methods provide complementary information about the soil P transformations. Thus, the paper highlights the importance of the use of different N-fixing leguminous tree species under different environmental conditions, production systems and management practices for recovering heavily degraded areas, which may be a suitable strategy through efficient management of P in highly weathered tropical soils in the Brazilian Atlantic Forest biome.

In NMR based metabolomics there is a need for tools to easily compare spectra and to extract the maximum of information from the data. The calculation of similarity and performing differential NMR spectroscopy provides important additional information for classification and validation in metabolomics experiments. From 13 different vegetable oils samples were analysed by 1H and 13C NMR. The similarity between spectra was calculated and differential NMR spectroscopy was used to discover marker compounds. The similarity between the individual spectra was calculated for the spectra of all samples. The similarity was used to verify and improve the alignment. For vegetable oils which showed a high similarity, e.g. chia seed oil and linseed oil, differential NMR spectroscopy was used to discover marker compounds. The calculation of similarity is an important tool to reveal variability between samples and spectra and can be used to verify data sets and improve alignment or binning procedures. With differential spectroscopy marker compounds are easily discovered. The methods can be seen as an important addition to the routine procedures of metabolomics experiments.

The illegal trade in counterfeit and fake drugs is a worldwide multi-billion dollar industry, not only generating enormous economic losses, but health problems for the general population, through direct toxicity, treatment failure and the increased generation of antibiotic resistance. Techniques for high-throughput testing of suspect medicines are needed to face the challenges of the problem. In this study we show that with nuclear magnetic resonance spectroscopy (NMR) drug compliance can be verified in a few minutes, providing data on drug identity, purity and quality without the necessity to develop a specific methodology and using a direct extraction with deuterated solvent. The evaluation of the data is facilitated by similarity calculations and differential NMR spectroscopy. The viability and limitations of this method were assessed, with the application on five different drugs, namely sertraline hydrochloride, alprazolam, vitamin D3, enalapril maleate and paracetamol, in which the individual dosage quantity of the active ingredient ranged from 750 mg down to 0.25 mg. The appropriate sample weight, solvent and internal standard were determined for each drug and quantification was carried out by choosing the most adequate NMR signals for each compound and the internal standard. With the method the accuracy of the quantification is somewhat sacrificed for increased speed in the analysis, but the measurements offer excellent precision and offer the possibility of external calibration. Spectral similarity calculations and differential NMR spectroscopy were used to compare different generic brands and detect eventual undeclared constituents and contaminants. In one brand of alprazolam tablets the undeclared constituent tristearin was found, while in paracetamol tablets the contaminant para-aminophenol was found at a level above the allowed by the legislation. The applicability and limitations of the method are discussed.

Cryptococcosis, caused by Cryptococcus spp., is an invasive fungal infection of the central nervous system, associated with high mortality, affecting mainly immunocompromised patients. Due to the development of resistance to the current therapy, there is an urgent need for less toxic and more effective antifungal agents. In this study, we describe the antifungal activity against Cryptococcus spp. of an aqueous seed extract from Allamanda polyantha (ASEAP) and two iridoids, plumieride and plumieridine, isolated from this extract with an antifungal activity. The capsule formation and the morphological alterations were evaluated using fluorescent microscopy. The cytotoxic activity was also investigated. The minimal inhibitory concentration (MIC) values of ASEAP for Cryptococcus gattii were 70 and 36 µg/ml (for the R265 and R272 strains, respectively) and 563 µg/ml for Cryptococcus neoformans H99. ASEAP inhibited C. neoformans H99 capsule formation, an important virulence factor, and decreased the cell body size for both the C. gattii strains. H99 cells also presented morphological alterations, with defects in bud detachment and nuclear fragmentation. Plumieride and plumieridine presented higher MIC values than ASEAP, indicating that other compounds might contribute to antifungal activity and/or that combination of the compounds results in a higher antifungal activity.

Ethnopharmacological relevance Cissampelos sympodialis Eichler (Menispermaceae) is popularly used in northeastern Brazil for the treatment of respiratory diseases such as bronchitis and asthma. Despite many pre-clinical pharmacological studies, the compounds mediating the anti-asthma activity of polar extracts of Cissampelos sympodialis leaves have not been definitively identified. Aim of the study Aim of the study: The aim of the study was to investigate the correlation between the bioactivity of polar extracts prepared from the leaves of C. sympodialis and the chemical composition using a 1H-NMR-based metabolomics approach. Material and methods The metabolic profile of the leaf polar extract during different phenological stages of the plant was investigated using 1H NMR spectroscopy while simultaneously screening for spasmolytic activity using guinea-pig tracheal preparations. The content of the alkaloids previously implicated in the bioactivity of Cissampelos sympodialis was determined by HPLC. Results PCA analysis of the 1H NMR data discriminated the extracts from different plant phenological stages. The contents of the major alkaloids decrease (from 2 ± 0.32 μg/mL for warifteine and 1 ± 0.14 μg/mL for methylwarifteine) to undetectable levels from 90 (CsL90 extract) and 120 (CsL120) days onwards for warifteine and methylwarifteine, respectively. All six extracts relaxed the trachea pre-contracted with carbachol, but the CsF210 extract was more potent (EC50 = 74.6 ± 7.9 μg/mL) compared to both CsL90 extracts and CsL180 in the presence of functional epithelium. PLS regression analysis of 1H-NMR spectral data demonstrated that the spasmolytic activity was better correlated with signals for flavonol derivatives. Conclusions Our data challenge the idea that warifteine and methylwarifteine mediate the spasmolytic activity of the polar extract of C. sympodialis leaves.

In NMR based metabolomics there is a need for tools to easily compare spectra and to extract the maximum of information from the data.The calculation of similarity and performing differential NMR spectroscopy provides important additional information for classification and validation in metabolomics experiments.From 13 different vegetable oils samples were analysed byThe similarity between the individual spectra was calculated for the spectra of all samples. The similarity was used to verify and improve the alignment. For vegetable oils which showed a high similarity, e.g. chia seed oil and linseed oil, differential NMR spectroscopy was used to discover marker compounds.The calculation of similarity is an important tool to reveal variability between samples and spectra and can be used to verify data sets and improve alignment or binning procedures. With differential spectroscopy marker compounds are easily discovered. The methods can be seen as an important addition to the routine procedures of metabolomics experiments.

Metabolomics is the area of research, which strives to obtain complete metabolic fingerprints, to detect differences between them, and to provide hypothesis to explain those differences [1]. But obtaining complete metabolic fingerprints is not an easy task. Metabolite extraction is a key step during this process, and much research has been devoted to finding the best solvent mixture to extract as much metabolites as possible.Here a procedure is described for analysis of both polar and apolar metabolites using a two-phase extraction system. D

Metabolomics is the area of research, which strives to obtain complete metabolic fingerprints, to detect differences between them, and to provide hypothesis to explain those differences [1]. But obtaining complete metabolic fingerprints is not an easy task. Metabolite extraction is a key step during this process, and much research has been devoted to finding the best solvent mixture to extract as much metabolites as possible.Here a procedure is described for analysis of both polar and apolar metabolites using a two-phase extraction system. D2O and CDCl3 are the solvents of choice, and their major advantage is that, for the identification of the compounds, standard databases can be used because D2O and CDCl3 are the solvents most commonly used for pure compound NMR spectra. The procedure enables the absolute quantification of components via the addition of suitable internal standards. The extracts are also suitable for further analysis with other systems like LC-MS or GC-MS.

To increase the limited knowledge about phosphorus (P) species in strongly weathered soils of agroforests in tropical regions, the soil organic P was determined in different cacao (Theobroma cacao L.) agroforestry systems from the Atlantic forest region of Brazil, varying in age and phosphate fertilizer application. For this purpose NaOH-EDTA extraction and solution 31P nuclear magnetic resonance spectroscopy (31P NMR) were used. The studied areas were agroforests with different management systems: cacao-cabruca, cacao + erythrina, and cacao + rubber tree, which were compared with unfertilized pasture and natural forest. The results show that the distribution of P species in soil varied according to the different management practices (P fertilization, tree species and tree density) and stability time (different ages) of the cacao agroforests with low input of phosphate fertilizer. In cacao agroforests, natural forest and pasture a large portion of soil organic P (Po) consisted of P-monoester with lower concentrations of DNA. This Po species was correlated positively with clay and soil organic carbon. However, the recent conversion of natural forest and pasture to cacao agroforests led to a decrease in DNA concentration. High concentrations of pyrophosphate found in all cacao agroforests could be an evidence of a high soil fungal activity in cycling and accumulation of this P species. Moreover, the high concentrations and relative proportions of Po and pyrophosphate species revealed a high potential of P supply to trees in case of suppression of the phosphate fertilization in these agroforestry systems.

Guided by the acetylcholinesterase inhibiting activity, the bisindole alkaloid 3′- R/S -hydroxyvoacamine was isolated from a stem extract of Tabernaemontana divaricata , a plant used in Thailand in traditional rejuvenation remedies for improving the memory. The structure of the alkaloid was elucidated by extensive use of NMR spectroscopy and the complete assignment of the 1 H and 13 C NMR spectra is reported. The alkaloid acted as a non-competitive inhibitor against AChE with an IC 50 value of 7.00 ± 1.99 μM. An HPLC method was developed for the quantitative analysis of the AChE inhibitor. It suggested that there was 12.4% (w/w) of 3′- R/S -hydroxyvoacamine in the alkaloid enriched fraction of T. divaricata stem.

Biopolymers as polyhydroxyalkanoates (PHA) composed by different co-monomers 3-hydroxybutyrate and 3-hydroxyhexanoate [P(3HB-co-3HHx)] has attracted interest since its properties are similar to low density polyethylene. Burkholderia sacchari produces this copolymer with a very low 3HHx molar fraction, about 2 mol%. B. sacchari mutant (unable to produce polymer) was engineered to host PHA biosynthesis genes (phaPCJ) from Aeromonas sp. In addition, a two-step bioprocess to increase biopolymer production was developed. The combination of these techniques resulted in the production of P(3HB-co-3HHx) with 3HHx content up to 20 mol%. The PHA content was about 78% of dry biomass, resulting in PHA volumetric productivities around 0.45gl-1h-1. The P(3HB-co-3HHx) containing 20 mol% of 3HHx presented an elongation at brake of 945%, higher than reported before for this PHA composition. Here we have described an approach to increase 3HHx content into the copolymer, allowing the precise control of the 3HHx molar fractions.

Ethanol extract obtained from dried leaves of Acmella oleracea afforded after a liquid/liquid partition procedure a larvicidal hexane fraction (LC50 = 145.6 ppm) and a non larvicidal dichloromethane one. From the inactive fraction, three amides were identified, two new structures, named deca-6,9-dihydroxy-(2E,7E)-dienoic acid isobutylamide (1), deca-8,9-dihydroxy-(2E,6Z)-dienoic acid isobutylamide (2) and the known nona-2,3-dihydroxy-6,8-diynoic acid 2-phenylethylamide (3). Bioassay-guided chromatographic fractionation of the hexane partition led to the identification of an amide mixture, nona-(2Z)-en-6,8-diynoic acid 2-phenylethylamide (4) and deca-(2Z)-en-6,8-diynoic acid 2-phenylethlylamide (5). This mixture was active against Aedes aegypti larvae at LC50 = 7.6 ppm. Low toxicity of crude extracts and derived fractions on Artemia salina nauplies showed the possibility of using them to control the A. aegypti mosquito larvae. This is the first report on larvicidal activity of acetylenic 2-phenylethylamides and their identification in A. oleracea leaves.

The present state-of-the-art of NMR in plant metabolomics is reviewed. Attention is paid to the different practical aspects of the application of NMR. The sample preparation, the measurement of the spectrum, quantitative aspects and data analysis are discussed. Each stage has its specific problems, which are pointed out and recommendations are made.

Hypericum connatum (Guttiferae) is used in southern Brazil in the treatment of lesions in the mouth, often related to acute herpetic gingivo-stomatitis. The chemical investigation of the plant revealed the presence of phloroglucinol derivatives and flavonoids. From the n-hexane extract of the aerial parts a phloroglucinol derivative, hyperbrasilol B, was isolated, while the methanolic extract afforded four flavonoids: amentoflavone, hyperoside, guaijaverine and luteoforol. The crude methanolic extract and fractions (n-hexane, dichloromethane and methanol) as well as the isolated compounds were tested for antiviral activity against herpes simplex viruses (HSV). Among the tested samples, luteoforol was the most active inhibiting the cytopathic effect (CPE) and reducing the viral titer of HSV-1 DNA viral strains KOS and VR733 (ATCC).

The preparations of cis-2,4,5-triaryl-4,5-dihydro-1H-imidazoles, (aryl = thien-2-yl or pyridin-2-yl) from aryl aldehydes, ammonium chloride and triethylamine in methanol, and their conversions to the trans-isomers are reported. Crystal structures of cis-(1: aryl = pyridin-2-yl), cis-[1: aryl = thien-2-yl·0.5H2O], trans-(1: aryl = thien-2-yl), and trans-{[(1: aryl = pyridin-2-yl)H]+[OAc]−·3H2O}, have been determined and compared with related structures.

Cyathenosin A, a spiropyranosyl derivative of protocatechuic acid was isolated from the stem pith of Cyathea phalerata Mart. Its structure was determined by MS, 1D and 2D NMR spectroscopic analyses and confirmed by single crystal X-ray analysis. Cyathenosin A is the first example of a naturally occurring compound containing a spirocyclic orthoester pyranosidic structure.

Baccharis illinita DC, commonly known as ‘‘cha ventura’’ or ‘‘erva milagrosa’’ (family Asteraceae) is an annual sub-shrub with yellowish flowers that grows in natural grasslands. Flowers of Baccharis illinita DC were collected in Serra do Falcao, Minas Gerais, and identified by the botanist Jose Badini. A voucher specimen (OUPR No. 3450) has been deposited in the Herbarium, Universidade Federal de Ouro Preto, Minas Gerais, Brazil.

From the leaves of Bauhinia forficata kaempferol and four flavonoid glycosides, 3,7-di-O-alpha-L-rhamnopyranosylkaempferol, 3,7-di-O-alpha-L-rhamnopyranosylquercetin, 3-O-[alpha-L-rhamnopyranosyl-(1->6)-beta-D-glucopyranosyl]-7-O-alpha-L-rhamnopyranosylkaempferol and 3-O-[alpha-L-rhamnopyranosyl-(1->6)-beta-D-glucopyranosyl]-7-O-alpha-L-rhamnopyranosylquercetin were obtained. From the flowers only the flavonoid 7-O-alpha-L-rhamnopyranosylkaempferol was isolated. The structures were established by chemical and spectroscopic methods.

Medium-chain-length polyhydroxyalkanoates are produced by Pseudomonas putida strain IPT046growing on carbohydrates. Analysis by gas chromatography and nuclear magnetic resonance of the elastomeric material revealed that PHAmcl is composed from essentially hydroxydecanoate (60–70%) and hydroxyoctanoate (20–25%) sequence units with a non-terminal double bond in about 6% of the side chains. The average molecular weight of PHAmcl is 223 kDalton and the X-ray diffractogram showed that 24% of the solid phase is crystalline. This biodegradable polyester presents a relative low glass transition temperature ()39.7 C) and melting point (56 C), is thermically stable (234 C) and displays appropriate thermomechanical properties for potential use as packaging film. 2003 Elsevier Science Ltd. All rights reserved.

The effect of different catalysts (NaY, Cr-VPI-5, acidic kaolinite clay, clayfen, and p-toluenesulfonic acid) on the reaction between cyclohexanone and methanol-d4 was investigated using GC-MS and in situ NMR spectroscopy at room temperature. An in situ IR spectroscopy analysis of pyridine adsorbed on the clay and NaY samples showed that they are both weakly acidic. Depending on the catalyst employed, acetalization, α-carbon deuteration, or both of these reactions occurred. With the clays only acetalization proceeded to yield 1,1-dimethoxycyclohexane with 90% conversion at room temperature. When zeolite Y was used, only deuteration of the cyclohexanone α-carbon was observed, while with the homogeneous p-toluenesulfonic acid catalyst, both deuteration of the α-carbons and the acetalization reaction proceeded.

Four samples, from two populations, of the liverwort Marchesinia mackaii were collected on Madeira and at the mainland of Portugal, at different collection times. The oil yields determined by hydrodistillation attained 0.5% (v/w). The essential oils isolated by distillation-extraction were analyzed by GC and GC/MS. The main components (>5%) were α-asarone (23–31%), 2,4,5-trimethoxyallylbenzene (10–23%), (E)-methyl isoeugenol (12–19%), β-asarone (11–13%) and β caryophyllene (7–16%).

A bioatividade de ácidos húmicos (AH) isolados de lodo da estação de tratamento de esgoto (AHL) e de vermicomposto (AHV) foi avaliada pela ação dessas substâncias sobre o transporte de prótons através da membrana plasmática de células de raízes de café e milho e sua relação com o desenvolvimento dessas espécies. Houve estímulo da área superficial radicular em ambas as espécies cultivadas com ambos AH, mostrando uma concentração ótima em torno de 40 mg L-1. Nessa condição, os tratamentos com AHL e AHV estimularam a H+-ATPase de membrana plasmática em plântulas de café e milho. Os AHL foram mais efetivos na promoção desses efeitos do que os AHV. A modificação do perfil cromatográfico dos AH em solução antes e após o cultivo das plântulas revelou que a interação planta-AH promoveu uma redistribuição das massas moleculares dessas substâncias, sugerindo uma dinâmica de mobilização de subunidades funcionais dos AH por exsudatos das raízes. A análise estrutural dos AH detectou a presença de grupamentos de auxina. A análise comparativa da ação desses dois AH sobre as espécies representantes de plantas monocotiledôneas (milho) e dicotiledôneas (café) apontam para a ativação da H+-ATPase de plasmalema como possível marcador metabólico de bioatividade dos ácidos húmicos. The bioactivity of humic acids (HA) isolated from sludge of the station of sewer treatment (HAL) and from vermicompost (HAV) was evaluated through the action of those substances on primary transport of protons of the plasma membrane of coffee and corn root cells and its relationship with the development of those species. A stimulation in the superficial area of roots was observed for both species cultivated with both humic acids, exhibiting an optimum concentration, about 40 mg L-1 of HA. In this condition the treatment with HAL and HAV stimulated the plasma membrane H+-ATPase of corn and coffee roots. HAL were more effective to promote those effects than HAV. The modification of the chromatographic profile of the HA in solution before and after the cultivation of the seedlings revealed that the interaction plant-HA promoted a rearrangement of the average molecular weight of those substances suggesting a dynamic mobilization of bioactive subunits of the HA by plant exudates. The structural analysis of the HA has detected the presence of auxin groups. A comparative analysis of the action of those HA on the monocotyledonous (corn) and dicotyledonous (coffee) plants indicates to the activation of plasmallema H+-ATPase as a possible metabolic marker for bioactivity of humic acids.

Three pentacyclic indole alkaloids, one novel named darcyribeirine (1) and the known isoreserpiline (2) and isoreserpine (3), were isolated from the root bark of the Rauvolfia grandiflora Mart. The structures were established by spectroscopic data.

A new secoiridoid glucoside has been isolated from Gronovia scandens L. (Loasaceae), namely 6-β-hydroxysweroside. The structure was mainly elucidated by spectroscopic methods. Fuertesia domingensis, another species from the subfamily Gronovioideae appeared to lack iridoid glucosides. The chemical relationships between Loasaceae and Hydrangeaceae is discussed.

Transformed root cultures of Anethum graveolens were induced by inoculation of aseptically grown seedlings with Agrobacterium rhizogenes carrying plasmid pRi 1855. The main component of the essential oils from the fruits and from the roots of the parent plant was carvone, whereas α-phellandrene and apiole were dominant in the oil from, respectively, the aerial parts and the hairy roots. The essential oils from the fruits, aerial parts and roots of the parent plant were at 2%, 0.3% and 0.06% (v/w), respectively, but only 0.02% (v/w) in the hairy root cultures. Growth of the hairy root cultures reached 600 mg dry wt/50 ml medium after 50 days. The essential oil composition did not change significantly during their growth.

[D-Leu1]-microcystin-LR is a recently discovered microcystin. We report the isolation of this microcystin analogue from a Microcystis aeruginosa strain isolated from the Lagoa de Iquipari, Rio de Janeiro, Brazil. The 1H and 13C NMR spectra were completely assigned in both MeOH-d4 and DMSO-d6. Further, the solution structure of this compound was investigated with the use of two-dimensional NMR and the amide proton temperature dependence, and was compared with those of its analogs, microcystin-RR and microcystin-LR. Copyright © 2002 John Wiley & Sons, Ltd.

Flindersia brayleyana F. Muell. contains the diprenylated coumarins 1 and 2, in addition to the known coumarins braylin (3) and brayleyanin (4). The structures of the new natural products were elucidated by extensive NMR analysis and mass spectra.

From the aerial parts of Hypericum polyanthemum Klotzsch ex Reichardt (Guttiferae), three chromenes, 6-isobutyryl-5,7-dimethoxy-2,2-dimethyl-benzopyran; 7-hydroxy-6-isobutyryl-5-methoxy-2,2-dimethyl-benzopyran and 5-hydroxy-6-isobutyryl-7-methoxy-2,2-dimethyl-benzopyran were isolated. Their structures were determined by NMR spectroscopic analyses.

A new natural quaternary alkaloid, Nb-methylvoachalotine (1), was obtained from the root bark of Tabernaemontana laeta together with three dimeric indole alkaloids, conodurine (2), voacamine (3) and tabernamine (4), and the monomeric indole alkaloids 19S-heyneanine (5), coronaridine (6) and voacangine (7). The known triterpenes alpha-amyrin acetate, beta-amyrin acetate, lupeol acetate and taraxasterol acetate and the phytosterol beta-sitosterol and its 3-O-beta-D-glucoside were also identified. The structures of the compounds were elucidated based on spectroscopic studies. Um novo alcalóide quaternário natural, Nb-metilvoachalotina (1), três alcalóides indólicos diméricos, conodurina (2), voacamina (3) e tabernamina (4), e os três alcalóides monoméricos 19S-heyneanina (5), coronaridina (6) e voacangina (7) foram isolados da casca das raízes de Tabernaemontana laeta. Os triterpenos conhecidos 3-O-acetil-alfa-amirina, 3-O-acetil-beta-amirina, 3-O-acetil-lupeol e 3-O-acetiltaraxasterol e os fitoesteróides beta-sitosterol e seu derivado 3-O-beta-D-glicopiranosídeo foram também identificados. As estruturas dos compostos foram elucidadas com base na análise de dados espectroscópicos.