Effect of provenance, plant part and processing on extract profiles from cultivated European Rhodiola rosea L. for medicinal use.

The demand for plant material of Rhodiola rosea L. (Crassulaceae) for medicinal use has increased recently, amid concerns about its quality and sustainability. We have analysed the content of phenylpropanoids (total rosavins) and salidroside in liquid extracts from 3-year old cultivated plants of European origin, and mapped the influence of plant part (rhizome versus root), genotype, drying, cutting, and extraction solvent to chemical composition. Rhizomes contained 1.5-4 times more salidroside (0.3-0.4% dry wt) and total rosavins (1.2-3.0%) than roots. The qualitative decisive phenylpropanoid content in the extracts was most influenced by plant part, solvent, and genotype, while drying temperature and cutting conditions were of less importance. We have shown that R. rosea from different boreal European provenances can be grown under temperate conditions and identified factors to obtain consistent high quality extracts provided that authentic germplasm is used and distinguished between rhizome, roots and their mixtures.

Cesium toxicity in Arabidopsis

Cesium (Cs) is chemically similar to potassium (K). However, although K is an essential element, Cs is toxic to plants. Two contrasting hypotheses to explain Cs toxicity have been proposed: (1) extracellular Cs+ prevents K+ uptake and, thereby, induces K starvation; and (2) intracellular Cs+ interacts with vital K+-binding sites in proteins, either competitively or noncompetitively, impairing their activities. We tested these hypotheses with Arabidopsis (Arabidopsis thaliana). Increasing the Cs concentration in the agar (Cs(agar)) on which Arabidopsis were grown reduced shoot growth. Increasing the K concentration in the agar (K(agad)) increased the Cs(agar) at which Cs toxicity was observed. However, although increasing Cs(agar) reduced shoot K concentration (K(shoot)), the decrease in shoot growth appeared unrelated to K(shoot) per se. Furthermore, the changes in gene expression in Cs-intoxicated plants differed from those of K-starved plants, suggesting that Cs intoxication was not perceived genetically solely as K starvation. In addition to reducing K(shoot) increasing Cs(agar) also increased shoot Cs concentration (Cs(shoot)), but shoot growth appeared unrelated to Cs(shoot) per se. The relationship between shoot growth and Cs(shoot)/Kt(shoot) suggested that, at a nontoxic Cs(shoot) growth was determined by K(shoot) but that the growth of Cs-intoxicated plants was related to the Cs(shoot)/K(shoot) quotient. This is consistent with Cs intoxication resulting from competition between K+ and Cs+ for K+-binding sites on essential proteins.

Assessment of the anthelmintic activity of medicinal plant extracts and purified condensed tannins against free-living and parasitic stages of Oesophagostomum dentatum

Background: Plant-derived condensed tannins (CT) show promise as a complementary option to treat gastrointestinal helminth infections, thus reducing reliance on synthetic anthelmintic drugs. Most studies on the anthelmintic effects of CT have been conducted on parasites of ruminant livestock. Oesophagostomum dentatum is an economically important parasite of pigs, as well as serving as a useful laboratory model of helminth parasites due to the ability to culture it in vitro for long periods through several life-cycle stages. Here, we investigated the anthelmintic effects of CT on multiple life-cycles stages of O. dentatum. Methods: Extracts and purified fractions were prepared from five plants containing CT and analysed by HPLC-MS. Anthelmintic activity was assessed at five different stages of the O. dentatum life cycle; the development of eggs to infective third-stage larvae (L3), the parasitic L3 stage, the moult from L3 to fourth-stage larvae (L4), the L4 stage and the adult stage. Results: Free-living larvae of O. dentatum were highly susceptible to all five plant extracts. In contrast, only two of the five extracts had activity against L3, as evidenced by migration inhibition assays, whilst three of the five extracts inhibited the moulting of L3 to L4. All five extracts reduced the motility of L4, and the motility of adult worms exposed to a CT-rich extract derived from hazelnut skins was strongly inhibited, with electron microscopy demonstrating direct damage to the worm cuticle and hypodermis. Purified CT fractions retained anthelmintic activity, and depletion of CT from extracts by pre-incubation in polyvinylpolypyrrolidone removed anthelmintic effects, strongly suggesting CT as the active molecules. Conclusions: These results suggest that CT may have promise as an alternative parasite control option for O. dentatum in pigs, particularly against adult stages. Moreover, our results demonstrate a varied susceptibility of different life-cycle stages of the same parasite to CT, which may offer an insight into the anthelmintic mechanisms of these commonly found plant compounds.

Inhibition of Mycobacterium tuberculosis tyrosine phosphatase PtpA by synthetic chalcones: Kinetics, molecular modeling, toxicity and effect on growth

Tuberculosis (TB) is a major cause of morbidity and mortality throughout the world, and it is estimated that one-third of the world`s population is infected with Mycobacterium tuberculosis. Among a series of tested compounds, we have recently identified five synthetic chalcones which inhibit the activity of M. tuberculosis protein tyrosine phosphatase A (PtpA), an enzyme associated with M. tuberculosis infectivity. Kinetic studies demonstrated that these compounds are reversible competitive inhibitors. In this work we also carried out the analysis of the molecular recognition of these inhibitors on their macromolecular target, PtpA, through molecular modeling. We observed that the predominant determinants responsible for the inhibitory activity of the chalcones are the positions of the two methoxyl groups at the A-ring, that establish hydrogen bonds with the amino acid residues Arg17, His49, and Thr12 in the active site of PtpA, and the substitution of the phenyl ring for a 2-naphthyl group as B-ring, that undergoes p stacking hydrophobic interaction with the Trp48 residue from PtpA. Interestingly, reduction of mycobacterial survival in human macrophages upon inhibitor treatment suggests their potential use as novel therapeutics. The biological activity, synthetic versatility, and low cost are clear advantages of this new class of potential tuberculostatic agents. (C) 2010 Elsevier Ltd. All rights reserved.

Atividade antimalárica de plantas medicinais da biorregião do Araripe-CE em modelo murino - Plasmodium berghei

Malaria, also popularly known as maleita , intermittent fever, paludism, impaludism, third fever or fourth fever, is an acute infectious febrile disease, which, in human beings, is caused by four species: Plasmodium falciparum, P. vivax, P. malariae and P. ovale. Malaria, one of the main infectious diseases in the world, is the most important parasitoses, with 250 million annual cases and more than 1 million deaths per year, mainly in children younger than live years of age. The prophylactic and therapeutic arsenal against malaria is quite restricted, since all the antimalarials currently in use have some limitation. Many plant species belonging to several families have been tested in vivo, using the murine experimental model Plasmodium berghei or in vitro against P. falciparum, and this search has been directed toward plants with antithermal, antimalarial or antiinflammatory properties used in popular Brazilian bolk medicine. Studies assessing the biological activity of medicinal plant essential oils have revealed activities of interest, such as insecticidal, spasmolytic and antiplasmodic action. It has also been scientifically established that around 60% of essential oils have antifungal properties and that 35% exhibit antibacterial properties. In our investigation, essential oils were obtained from the species Vanillosmopsis arborea, Lippia sidoides and Croton zethneri which are found in the bioregion of Araripe-Ceará. The chemical composition of these essential oils was partially characterized and the presence of monoterpenes and sesquiterpenes. The acute toxicity of these oils was assessed in healthy mice at different doses applied on a single day and on four consecutive days, and in vitro cytotoxicity in HeLa and Raw cell lines was determined at different concentrations. The in vivo tests obtained lethal dose values of 7,1 mg/Kg (doses administered on a single day) and 1,8 mg/Kg (doses administered over four days) for 50% of the animals. In the in vitro tests, the inhibitory concentration for 50% of cell growth in Hela cell lines was 588 μg/mL (essential oil from C. zethneri after 48 h), from 340-555 μg/mL (essential oil from L. sidoides, after 24 and 48 h). The essential oil from V. arborea showed no cytotoxicity and none of the essential oils were cytotoxic in Raw cell lines. These data suggest a moderate toxicity in the essential XVIII oils under study, a finding that does not impede their testing in in vivo antimalarial assays. Was shown the antimalarial activity of the essential oils in mice infected with P. berghei was assessed. The three species showed antimalarial activity from 36%-57% for the essential oil from the stem of V. arborea; from 32%-82% for the essential oil from the leaves of L. sidoides and from 40%-70% of reduction for the essential oil from the leaves of C. zethneri. This is the first study showing evidence of antimalarial activity with these species from northeast Brazil. Further studies to isolate the active ingredients of these oils are needed to determine if a single active ingredient accounts for the antimalarial activity or if a complex integration of all the compounds present occurs, a situation reflected in their biological activity

Detached leaf culture: Viability to evaluate 2,4-D toxicity symptoms in cotton apex leaves

To study the viability of detached leaf culture technique, studies were carried out with detached leaves from cotton apex (true trilobed leaves). The prepared leaves were sprayed with 2,4-D amine and ester, at rates of 10, 30, 70, and 100% of the recommended doses. Detached leaves without herbicide spray were used as controls. Simultaneously, a greenhouse experiment was conducted with the same treatments as used for the detached leaves experiment. Toxicity was measured through a 0-to-5 grading according to the percentage of affected leaf area in the detached leaves experiment or examining the affected rate of whole plant as indicated in the greenhouse. Results showed that the ester form of the herbicide induced earlier and more severe toxicity symptoms in detached leaves and greenhouse grown plants. Positive and significant correlations (p < 0.001) were found between toxicity results obtained at 7 and 14 days after application in detached leaves and greenhouse plants (r = 0.97 and 0.92, respectively). Negative, significant correlations (p < 0.005) were found between the toxicity levels found at 7 and 14 days after application in detached leaves and dry matter of cotton plants grown in the greenhouse (r = -0.92 and -0.92, respectively).

Effects of aluminum on plant growth and nutrient uptake in young physic nut plants

Aluminum (Al3+) toxicity is a major limiting factor to crop productivity in acid soils. The effects of aluminum on root and shoot growth of physic nut (Jatropha curcas L.) young plants and, the uptake and distribution of phosphorus, calcium, magnesium and aluminum in the roots and shoots were investigated in the present study. Plants were grown in 2.5L pots in a greenhouse. After fourteen days of adaptation to nutrient solution, plants were exposed to Al concentrations of 0, 370, 740, 1,100 and 1,480 mu mol L-1, corresponding to an active Al3+ solution of 13.3, 35.3, 90.0, 153.3 and 220.7 mu mol L-1, respectively. The dry matter partitioning between roots, stems and leaves, and the concentrations of P, Ca, Mg and Al in plant tissue, were measured after 75 days exposure to Al. The increasing level of Al3+ activity in solution progressively decreased the growth of the shoot and root of physic nut plants, and at the two highest active Al3+ levels, plants showed morphological abnormalities typical of the toxicity caused by this metal. Higher Al3+ activity reduced P concentrations in leaves and Ca and Mg in leaves and roots of physic nut, demonstrating the effect of Al on the uptake, transport and use of these nutrients by plants. The Al accumulated preferentially in the roots of physic nut, whereas only a small amount was transported to shoots.

Subchronic Toxicity Evaluation of a Treated Urban Sewage Sludge

Disposal of tons of sludge produced daily by sewage treatment plants in large cities is a serious problem. Because recycling and application in agriculture have been proposed, the Brazilian National Environmental Council (CONAMA, 2006) issued a legal norm that regulates the use of the sewage sludge (SS) in crops. Due to the complex chemical nature of such products, characterization by analytical methods for health and environmental risk assessment has severe limitations. To overcome such limitations, it is necessary to (1) assess the toxicological potential of SS and (2) identify possible adverse effects in vivo in order to provide critical information for future environmental regulations. The present study was conducted to determine the potential toxicity of SS obtained from a representative urban treatment plant located in the São Paulo State, Brazil. Male and female Wistar rats were fed ad libitum a pelleted diet containing varying amounts of SS. No relevant clinical, hematological, urinary, or gross organ morphological alterations were observed in both genders of rats orally exposed to SS at up to 3.8 g/kg/d for 90 d. Sewage slude produced increased incidence of centrilobular hepatocyte hyperplasia at the high dose and significantly increased aspartate aminotransferease (AST) activities at all doses in both genders. Although the present data indicate some liver involvement, these alterations were considered adaptative and not toxicologically relevant, as the responses were relatively mild, not dose dependent, and no other parameters were markedly affected. The present results may contribute to the establishment of protocols for potential usage in SS agricultural soil application.

Hymenaea stigonocarpa Mart. ex Hayne: A Brazilian medicinal plant with gastric and duodenal anti-ulcer and antidiarrheal effects in experimental rodent models

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Brazilian Medicinal Plant Acts on Prostaglandin Level and Helicobacter pylori

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Differences in gastroprotective and mutagenic actions between polar and apolar extracts of Ananas ananassoides

Several plants are used in folk medicine to treat gastrointestinal disorders. Ananas ananassoides (Baker) L. B. Smith (Family Bromeliaceae) is a medicinal plant commonly used in the central region of Brazil against gastric pain. We evaluated two extracts (methanol [MeOH] and dichloromethane [DCM]) obtained from the leaves of A. ananassoides for their ability to protect the gastric mucosa against injuries caused by necrotizing agents (0.3 M HCl/60% ethanol, absolute ethanol, non-steroidal anti-inflammatory drugs, and pylorus ligation) in mice and rats. The best results were obtained after pretreatment with the DCM extract, whereas the MeOH extract did not show any significant anti-ulcerogenic activity but presented mutagenic action. The mechanism of action of the DCM extract suggested the effective participation of endogenous sulfhydryl group in the gastroprotective action. The data, taken together with the absence of acute toxicity and mutagenicity, indicate the apolar extract, instead of the polar, extract of A. ananassoides as a safe and potential new anti-ulcerogenic drug.

Development and characterization of microsatellite markers for Lychnophora pinaster: a study for the conservation of a native medicinal plant

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Toxicity of barbatimao to Apis mellifera and Scaptotrigona postica, under laboratory conditions

Two species of plants commonly known as barbatim (a) over tildeo occur in Brazil, Stryphnodendron adstringens (Fabaceae) (true barbatim (a) over tildeo) and Dimorphandra mollis (Caesalpiniaceae) (false barbatim (a) over tildeo). These two species have a similar flowering period and are considered by beekeepers to cause bee mortality during this period. Flowers were collected from both species, dehydrated, ground and incorporated into an experimental diet for bees of two different species, Apis mellifera and Scaptotrigona postica. Both plant species were toxic to A. mellifera, reducing their median survival. D. mollis was toxic to S. postica, and Stryphnodendron adstringens reduced median survival of this bee species even when used at a concentration of 2.5%. In a choice experiment carried out with A. mellifera and the two plant species, the honey bees could choose not to feed on the diets containing the flowers, and feed on sugar and honey instead, but they did not. This shows us that the flowers of S. adstringens were not repellent to the bees. The plants were more toxic to A. mellifera than to Scaptotrigona postica, a result that can be explained by the fact that A. mellifera was introduced into Brazil whereas S. postica is a native stingless bee.

Sewage sludge toxicity in edaphic organism: Analysis of midgut responses in the diplopod Rhinocricus padbergi

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Aluminum in corn plants: influence on growth and morpho-anatomy of root and leaf

A toxicidade do alumínio (Al) é um dos fatores mais limitantes para a produtividade. Esta pesquisa foi realizada para avaliar a influência do Al, em solução nutritiva, na altura de plantas, no peso da matéria seca e nas alterações morfoanatômicas de raízes e folhas de milho (Zea mays L.). O experimento foi conduzido em casa de vegetação com tratamentos constituídos de cinco doses de Al (0; 25; 75; 150; e 300 µmol L-1) e seis repetições. As soluções foram constantemente aeradas e o pH foi ajustado a 4,3, inicialmente. A matéria seca da parte aérea e das raízes e a altura das plantas diminuíram significativamente com o aumento da concentração de Al. As raízes de plantas de milho cultivadas em soluções com Al tiveram seu crescimento inibido e apresentaram menos raízes laterais e desenvolvimento do sistema radicular inferior, em comparação com as das plantas-controle. As folhas das plantas crescidas em soluções que continham 75 e 300 µmol L-1 de Al não apresentaram muita diferença anatômica em relação às das plantas-controle. A bainha da folha das plantas exposta ao Al apresentou epiderme uniestratificada revestida por uma fina camada de cutícula e as células da epiderme e do córtex foram as que menos se desenvolveram. No feixe vascular, o metaxilema e protoxilema não tinham paredes secundárias, e o diâmetro de ambos foi muito menor quando comparado com os das plantas-controle.