103 resultados para Physical-chemical analysis
Resumo:
Alho do mato (Cipura paludosa, Iridaceae) is a medicinal plant found in the Amazon rain forest, North of Brazil. It has been used to treat algic, inflammatory and infectious processes. The aim of this study was to evaluate the anti-inflammatory and antinociceptive action of the crude Cipura paludosa ethanolic extract at concentrations ranging between 2.0 and 4.0% in Oil and Water cream formulations for topical use. The physical-chemical stability of the formulations was monitored over a six-month period with the use of accelerated stability tests. In order to evaluate the anti-inflammatory and antinociceptive activities, we used a paw edema test induced by carrageenan and a formalin test, respectively. The paw edema test showed that there was a statistical difference in the control group in relation to the treatments. The formalin test did not confirm antinociceptive action of the treatments with the extract in the early phase of the test. However, statistical difference was confirmed for the treatments in relation to the control in the late phase. The antinociceptive and anti-inflammatory activities of Cipura paludosa preparations, as demonstrated in the results, at least partially support the ethno-medical uses of this plant.
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In the last years many populations of anurans have declined and extinctions have been recorded. They were related to environmental pollution, changes of land use and emerging diseases. The main objective of this study was to determine copper sensitivity of the anuran of the Amazon Rhinella granulosa and Scinax ruber tadpoles at stage 25 and Scinax ruber eggs exposed for 96 h to copper concentrations ranging from 15 µg Cu L-1 to 94 µg Cu L-1. LC50 at 96 h of Rhinella granulosa Gosner 25, Scinax ruber Gosner 25 and Scinax ruber eggs in black water of the Amazon were 23.48, 36.37 and 50.02 µg Cu L-1, respectively. The Biotic Ligand Model was used to predict the LC50 values for these species and it can be considered a promising tool for these tropical species and water conditions. Copper toxicity depends on water physical-chemical composition and on the larval stage of the tadpoles. The Gosner stage 19-21 (related to the appearance of external gills) is the most vulnerable and the egg stage is the most resistant. In case of contamination by copper, the natural streams must have special attention, since copper is more bioavailable.
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The authors repport in this paper, the results of trials by means of which were determined the composition and nutritive value of three grasses, that are cultivated in Piracicaba, in State of São Paulo, Brazil: Capim jaragaá, Hyparrhenia rufa, (Nees.) Stapf. (hay); capim de Rhodes, Chloris gayana, Kunth. (hay), and milho Santa Rosa, Zea mays, L. (silage). The digestion trials were carried out with sheep, following the technique of MEAD and GUILBERT. The chemical analysis of the forages were made by methods usually employed. The results are in the tables I and II, of this paper.
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1. Analyses of soluble sulphates in 2 N ammonium chloride extracts of 24 samples of soils of the state of São Paulo, Brazil, S. A., showed a sulphur content varying from 0,0013 g per 100 g (found in the b layer of a genuine "terra roxa") to 0,007 g per 100 g of soil (b layer of a soil of depression without definite characteristics). (The results are expressed as elemental sulphur). Determinations of total sulphur in 56 samples of soils of the same state using the method of fusion with sodium carbonate and sodium nitrate revealed 0.007 g of elemental S per 100 g of soil as the lowest value (found in several soil types) and 0.096 g as the highest one (found in the b layer of an ar-quean soil). Apparently soluble sulphates accumulate in the upper layers and total sulphur does the opposite. It was found a strong correlation between total S and carbon content. 2. Under laboratory conditions, in a compost of fresh soil, powdered sulphur and apatite, it was verified after a three months period of incubation that the pH value lowered from 6.30 to 3.23; the citric acid solubility of apatite increased to 271.1 per cent of the original one. Lupinus sp. grown in soil manured with sulphur and apatite has showed fresh and dry weights higher than the plants in control pots; the results are significant at 5% level of probability; phosphorus content is also higher in the manured plants. It was observed a net influence of the apatite plus sulphur treatment on the weight of root nodosities that was four times greater than in the control plants. 3. Nearly five hundred determinations of S, N and P were carried out in 35 species of plants cultivated in the state of São Paulo. A great variation in the amounts of these elements was observed. As a general rule, the leaves contain more sulphur than the stems and roots show the lowest percentages. The conjunct roots and stem of guar (Cyamopsis psoraloides) revealed only 0.019 per cent sulphur; the leaves of kale showed the highest sulphur content, i. e., 2.114%. Apparently there is no correlation between the amounts of S, N and P. The ratio S/N increases from 0.006 (guar) to 0.485 (kale). The ratio S/P, always higher than the corresponding S/N, increases from 0.082 (guar) to 6.381 (older leaves of tomato plants). It is interesting to mention that several among the most important crops in the state of São Paulo namely, cotton, rice, coffee and sugar cane contain more sulphur than phosphorus. 4. Tomato plants cultivated in nutrient solution lacking sulphur showed the following visual symptons of deficiency : chlorosis first in the younger leaves and afterwards in all the leaves; anthocyanin pigments in the petioles and stems; absence of fruits; primary roots stunted and secondary ones longer than in the control plants; stems slender, hard, woody. The histological study of petioles suffering from sulphur deficiency revealed anthocyanin in the parenchyme layer instead of clo-rophyll pigments observed in normal petioles; in the chlorotic leaves the large chloroplasts present only the stroma but the small ones have a little amount of green pigments. Chemical analysis revealed in the abnormal plants : less sulphur and an increased proportion of phosphorus; older leaves contain more sulphur and less phosphorus than the younger ones probably due to physiological difficulties in translocation of sulphur bearing material; increased amount of total N attributed to accumulation of nitrates; marked decrease in ash, sugars and starch; increased proportion of crude fiber and dry material. In the plants suffering from sulphur deficiency photosyntetic rate decreased 34 per cent. 5. Tomato plants were succesfully cultivated in nutrient solution in absence of mineral sulphur but in presence of cysteine. The plants absorbed sulphur, under that form and were able to grow up quite well; the fruiting was normal. In this way rested cleary demonstrated the possibility of absorption of organic sulphur without previous mineralization and its utilization in the building up of protein molecules.
Resumo:
The authors repport in this paper, the results of trials by means of which were determined the composition and nutritive value of Capim Jaraguá, Hyparrhenia rufa (Nees) Stop/, cultivated in Piracicaba, in State of São Paulo, Brazil. The experiments were made with hay, silage and also the grass at three different stages: before, during and after blooming. The digestion trials were carried out with sheep, following the technique of MEAD and GUILBERT. The chemical analysis of the forages were made by methods usually employd. The results are in the table XXIV e XXV of this paper.
Resumo:
Young coffee plants (Coffea arabica L., var. Mundo Novo) were grown in nutrient solution purified from micronutrients contaminants by the method of MUNNS & JOHNSON (1960). All plants, except those in the control treatment, wer given all macronutrients and all micronutrients except one which was omitted in order to induce its shortage. Symptoms of deficiency were obtained for all known micronutrients but chlorine. Measurements, observations and chemical analysis of leaves allowed the following main conclusions to be drawn. 1. The relative influence of micronutrients in growth-measured by the fresh weight of the entire plant - was as follows: -Fe -Zn -Cu -Mo -Mn complete = -B = -CI. that is: the omission of iron from the nutrient solution caused the severest reduction in growth; lack of B and Cl had no effect. 2. Symptoms of deficiency of B, Fe, Mn, and Zn were found to be in good agreement with those in the literature. Effects of Cu and Mo shortage, however, had not been described so far: In the case of the Cu-deficient plants, the younger leaves were distorted, having an "S" shape, due probably to lack of growth of the veins; they lost their green color and developed rather large, necrotic patches near the margins. When molybdenum was omitted from the nutrient solution yellow spots develop near the margen of subterminal (fully mature) leaves; they became necrotic; there was a characteristic downward curling of the leaf blade along the mid rib so that the opposite edges touched each other underneath. 3. The levels of micronutrients found in normal and deficient leaves are given in Table 4. It is hoped that those values will serve as a basis of judgement of micronutrient contents found in leaves of field grown plants.
Resumo:
WATER-CULTURE EXPERIMENTS. Two water-culture experiments were carried out to study the absorption and the translocation of radiozinc in young coffee plants as influenced by two factors, namely, concentration of heavy metals (iron, man ganese, copper and molybdenum) and method of application. Inert zinc was supplied at an uniform rate of 0. 05 p. p. m.; the levels of iron supply were 0, 1.0, and 10.0 p. p.m.; manganese was supplied in three doses 0, 0.5, and 5.0 p. p.m.; copper- 0, 0. 02, and 0. 2 p. p. m.; molybdenum- 0, 0. 01, and 0. 1 p. p. m. When applied to the nutrient solution the activity os the radiozinc (as zinc chloride) was 0. 15 microcuries per plant. In the study of the leaf absorption, Zn65 was supplied at the level of 0. 10 microcuries per plant; in this case the radioative material was brushed either on the lower or on the upper surface or both two pairs of mature leaves. The absorption period was 8 weeks. The radioactivity assay showed the following results: 1 - Among the heavy metals herein investigated the iron concentration did not affect the uptake of the radiozinc; by raising the level of Mn, Cu and Mo ten times, the absorption dropped to 50 per cent and even more when compared with the control plants; when, however, these micronutrients were omitted from the nutrient solution, an increase in the uptake of zinc was registered in the minus Cu treatment only. The effects of high levels of Mn, Cu and Mo probably indicate an interionic competition for a same site on a common binding substance in the cell surface. 2 - The absorption of the radiozinc directly applied to the leaf surface reached levels as high as 8 times that registered when the root uptake took place. Among the three methods of application which have been tried, brushing the lower surface of the leaves proved to be the most effective; this result is easily understood since the stomatal openings of the coffee leaves an preferentially located in the lower surface - in this treatment, about 40 per cent of the activity was absorved and around 12 per cent were translocated either to the old or to the newer organs. Chemical analyses for heavy metals, were carried out only in the plants received Zn65Cl2 in the nutrient solution; the results were as follows; 1 - Control plants had, per 1,000 gm, of dry weight the following amounts in mg.: Zn- 48 in the roots and 29 in the tops; Fe- 165 in the roots and 9 in the tops; Mn- 58 in the roots and 15 in the tops, Cu- 15 in the roots and 1. 2 in the tops; Mo- 2. 8 in the roots and 0. 45 in the tops. 2 - The effect of different levels of micronutrients in the composition of the plants can be summarized as follows: Fe and Zn- when omitted from the nutrient solution, the iron and zinc contents in the roots decreased, no variation being noted in the tops; the higher dosis caused an accumulation in the roots but no apparent effect in the tops; Mn- by omitting this micronutrient a decrease in its content in the roots was noted, where as the concentration in the tops was the same; Mo- no variation in roots and tops contents when molybdenum was omitted; higher dosis of manganese and molybdenum increased the amounts formed both in the roots and in the tops. 3 - The influence of the different concentrations of micronutrients heavy metals on the zinc content of the coffee plants can be described by saying that: Fe and Mo- no marked variation; Mn- no effect when omitted, reduced amount when the high dosis was supplied; Mn- when the plants did not receive manganese the zinc content in roots and tops was the same as in the control plants; a decrease in the zinc content of the total plant occurred when the high dosis was employed; Cu -the situation is similar to that described for manganese. Hence, results showed by the chemical analyses roughly correspond to those of the radioactivity assay; the use of the tracer technique, however, gave best informations along this line. SOIL-POTS EXPERIMENTS. The two types of soils which when selected support the most extensive coffee plantations in the State of São Paulo, Brazil: "arenito de Bauru", a light sandy soil and "terra roxa legitima", a red soil derived from basalt. Besides NPK containing salts, the coffee plants were given two doses of inert zinc (65 and 130 mg ZnCl2 per pot) and radiozinc at a total activity of 10(6) counts/minute. The results of the countings can be summarized as follows: 1 - When plants were grown in "arenito de Bauru" the activity absorbed as per cent of the total activity supplied was not affected by the dosis of inert zinc. The highest value found was around 0. 1 per cent. 2 - For the "terra roxa" plants, the situation is almost the same; there was, however, a slight increase in the absorption of the radiozinc when 130 mgm of ZnClg2 was given: a little above 0. 2 per cent of the activity supplied was absorbed. The results clearly show that the young coffee plants practically did not absorb none of the zinc supplied; two reasons at least could be pointed out to explain such a fact: 1 - Zinc fixation by an exchange with magnesium or by filling holes in the octahedral layer of aluminosilicates, probably kaolinite; 2 - No need for fertilizer zinc in the particular stage of life cycle under which the experiment was set up. The data from chemical analysis are roughly parallel to the above mentioned. When one attempts to compare - by taking data herein reported zinc uptake from nutrient solution, leaf brushing or from fertilizers in the soil, a practical conclusion can be drawn: the control of zinc deficiency in coffee plants should not be done by adding the zinc salts to the soil; in other words: the soil applications used so extensively in other countries seem not to be suitable for our conditions; hence zinc sprays should be used wherever necessary.
Resumo:
Leaf samples from coffee plants under three different fertilizations, namely NPK, NP and PK, were collected for chemical analysis. It was found that the contents of N, K, Ca, Mg and S in the first, second, third and fourth pair of leaves were the same from the statistical point of view. On the onder hand, there was a significant effect of the position of the leaf in the branch on the P content, which was higher in the first pair. With the exception of the P level ,the four pairs of leaves are chemically uniform. Nevertheless it is not considered as convenient to mix all kinds of leaves into one sample, since the composition may vary a great deal when sampling is done some other time, such as the period of fruit growing. It is recommended therefore that either the third or the fourth pair leaves should be collected for routine work in foliar diagnosis.
Resumo:
Sand culture experiments, using a sub-irrigation technique, were installed in order to find out the effects of the macronutrients N, P, K, Ca, Mg and S on growth, aspect, mineral composition, length of fibers, thickness of cell wall and cellulose concentration in slash pine. The aim was to obtain, under controlled conditions, basic information which could eventually lead to practical means designed to increase the rate of growth and to make of slash pine a richer source of cellulose. Nitrogen, Phosphorus, Potassium Experiment A 3 x 3 x 3 factorial design with two replicates was used. Nitrogen was supplied initially at the levels of 25, 50 and 100 ppm; phosphorus was given at the rates of 5, 10 and 20 ppm; potassium was supplied at the rates of 25, 50 and 100 ppm; six months after the experiment was started the first level for each element was dropped to zero. Others macro and all micronutrients were supplied at uniform rates. Fifteen hours of illumination per day were provided. The experimental technique for growing the slash pine seedlings proved quite satisfactory. Symptoms of deficiency of nitrogen, phosphorus and potassium were observed, described and recorded in photographs and water colors. These informations will help to identify abnormalities which may appear under field conditions. Chemical analysis of the several plant parts, on the other hand, give a valuable means to assess the nutritional status of slash pine, thus confirming when needed, the visual diagnosis. The correctness of manurial pratices, on the other hand, can be judged with the help of the analytical data tabulated. Under the experimental conditions nitrogen caused the highest increases on growth, as measured by increments in height and dry weights, whereas the effects of phosphorus and potassium were less marked. Cellulose concentration was not significantly affected by the treatments used. Higher levels of N seemed to decrease both length of fiber elements and the thickness of cell wall. The effects of P and K were not well defined. Calcium, Magnesium, Sulfur Experiment A 3 x 3 x 3 factorial design with two replicates was used. Calcium was supplied initially at the levels of 12.5, 25 and 50 ppm; magnesium and sulfur were given at the rates of 6, 12.5 and 25 ppm. Other macro and micronutrients were supplied at uniform rates, common to all treatments. Three months after starting the experiment the first level for each element was dropped to zero. Symptoms of deficiency of calcium, magnesium and sulfur were observed, described and recorded as in the case of the previous experiment. Chemical analysis were made, both for mineral content and cellulose concentration. Length of fibers and thickness of cell wall were measured. Both calcium and magnesium increase height, sulfur failing to give significant response. Dry weight was beneficially affected by calcium and sulfur. The levels of calcium, magnesium and sulfur in the needles associated with deficiency and maximum growth are comparable with those found in the literature. Cellulose concentration increased when the level of sulfur in the substrate was raised. The thickness of cell wall was negatively affected by the treatments; no effect was observed with regards to length of fibers.
Resumo:
In order to obtain informations concerning the dry matter production and extraction of nutrients by the fruits of the varieties 'Ohio Beauty' and 'Brasil', a trial was conducted on a Latossol Vermelho Escuro-Orto (USTOX) at Buri , State of São Paulo, Brazil. The fruits were collected from trees grafted on 'Doucin' being 1-2; 3-4; 4-5, and 6-7 years old. Chemical analysis were run on the fruits for: N, P, K, Ca, Mg, S, B, Cu, Fe, Mn, Zn, and Mo; as well for the dry mat ter production. The main conclusions are as follows: a) differences were observed on dry matter production of fruits by the two varieties at the different stages of growth; b) differences were observed on exportation of nutrients between the two varieties concerning the fruit growth period- the nutrient exportation by the fruits obeyed following order: K>N>P>S>Ca>Mg>Fe>B > Cu > Mn > Zn > Mo.
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Lutzomyia (Lutzomyia) cruzi has been named as a probable vector of Leishmania chagasi in Corumbá, Mato Grosso do Sul, Brazil. Taxonomically L. cruzi is closely related to the L. longipalpis species complex. Females of L. cruzi and L. longipalpis are morphologically indistinguishable and associated males must be examined carefully to confirm identifications. Chemical analysis hexane extracts of male L. cruzi has revealed the presence of a 9-methylgermacrene-B (C16), a homosesquiterpene (mw 218) previously shown to be the sex pheromone of one of the members of the L. longipalpis species complex.
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We analyzed data from historical controls treated with meglumine antimoniate to compare the frequency of adverse events observed in patients with cutaneous leishmaniasis treated with the same dose of meglumine antimoniate contaminated with heavy metals in an endemic area of the State of Bahia, Brazil. Group A patients were treated in 2000 with the drug produced by Eurofarma Laboratórios Ltda., São Paulo, Brazil (lot A) and group B patients were treated in 1996 with the reference drug produced by Rhodia Farma Ltda., São Paulo, Brazil (lot B). We observed an unusual higher frequency of skin reactions in group A patients. However, all type of adverse events observed in group A were also observed in group B. The physico-chemical analysis of these lots revealed that lot A had lower pH and higher concentration of total and trivalent antimony, lead, cadmium, and arsenic. Our findings suggest that the skin reactions could be attributed to heavy metal contamination of lot A.
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This study was carried out to evaluate the molecular pattern of all available Brazilian human T-cell lymphotropic virus type 1 Env (n = 15) and Pol (n = 43) nucleotide sequences via epitope prediction, physico-chemical analysis, and protein potential sites identification, giving support to the Brazilian AIDS vaccine program. In 12 previously described peptides of the Env sequences we found 12 epitopes, while in 4 peptides of the Pol sequences we found 4 epitopes. The total variation on the amino acid composition was 9 and 17% for human leukocyte antigen (HLA) class I and class II Env epitopes, respectively. After analyzing the Pol sequences, results revealed a total amino acid variation of 0.75% for HLA-I and HLA-II epitopes. In 5 of the 12 Env epitopes the physico-chemical analysis demonstrated that the mutations magnified the antigenicity profile. The potential protein domain analysis of Env sequences showed the loss of a CK-2 phosphorylation site caused by D197N mutation in one epitope, and a N-glycosylation site caused by S246Y and V247I mutations in another epitope. Besides, the analysis of selection pressure have found 8 positive selected sites (w = 9.59) using the codon-based substitution models and maximum-likelihood methods. These studies underscore the importance of this Env region for the virus fitness, for the host immune response and, therefore, for the development of vaccine candidates.
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Toxic effects of essential plant oils in adult Sitophilus oryzae (Linnaeus) (Coleoptera, Curculionidae). Stored grains are subject to losses in quality nutritional value and in sanitation from the time they are stored to the time they are consumed. Botanical insecticides may offer an alternative solution for pest control. The objective was to test the insecticidal properties of the essential oils of Cymbopogon citratus (leaf), Zingiber officinale (root) and Mentha sp. (leaf). The efficacy of these oils was tested to control the rice weevil, S. oryzae, using hydrodistillation. Chemical analysis of the essential oils was carried out by gas chromatography. Major components of C. citratus were geranial (48%) and neral (31%), of Z. officinale were α-zingibereno (13%), geranial (16%), neral (10%) and α-farneseno (5%) and of Mentha sp. was menthol (92%). Bioassays were carried out by fumigation and topical application. In topical application assays, the essential oil of C. citratus had greater toxicity (LC50 0.027 µL mL-1) and shorter exposure time than the oils of the other two plants. After 24 h and 48 h, 70% and 100% mortality of S. oryzae occurred, respectively. In fumigation assays, essential oil of Z. officinale had a lower LC50 (1.18 µL cm-2) and 70% mortality after 24 h exposure. Therefore, we recommend the use of essential oils of C. citratus and Z. officinale to control the rice weevil S. oryzae.
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Defensive behavior associated with secretions from the prosternal paired glands of the larvae of Heliconius erato phyllis Fabricius (Lepidoptera, Nymphalidae). Our work presents for the first time, the defensive behavior associated with the release of the product of the prosternal paired glands of the larva of Heliconius erato phyllis Fabricius, 1775 (Lepidoptera, Nymphalidae, Heliconiinae). The prosternal glands were first described for larvae of H. erato phyllis. They are formed by two types of glandular structures: the impair gland and the paired glands. The prosternal glands are located within the conical integumentary sac, which in turn is situated on the individual's prosternum. The main goal of this study is to analyze the existence of any secretion from the prosternal paired glands, and check the action mode of this secretion. The methodology used for chemical analysis of the glands included the aeration and, analysis in gas chromatography and gas chromatography-mass spectrometry. The results show that the prosternal glands do not produce volatiles. Bioassays were conducted with simulated and natural attacks and revealed that the prosternal paired glands produce secretions of defense together with silk produced by labials glands as a defense strategy, described for the first time, against ants. The strategy consists in wrapping the ant with silk threads, the entire wrapped object moved to the end of the body, with the aid of the legs and prolegs, and possibly fixed in a nearby place. Evidence for the existence of a conical integumentary sac in larvae of other species and families of Lepidoptera allows us to propose the possibility of occurrence of prosternal paired glands with defensive function in these other groups as well.