106 resultados para Extrato etéreo


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In this work a Plackett-Burman Design with 8 factors and 12 trials in 2 levels with 3 repetitions at the center point was used in order to investigate the influence of the concentration of chitosan, peptone, yeast extract, NaNO3, K2HPO4, KCl, MgSO4.7H2O and FeSO4 on chitosanase production by Metarhizium anisopliae. Runs were carried out using submerged discontinuous cultivation for enzyme production. The results of the Plackett & Burman Design showed that only two factors, chitosan concentration as well as FeSO4 had influence on chitosanolytic activity, while the increase in concentration of other factors not contributed significantly to the quitosanolítica activity. Cultivation medium optimization for enzyme production was carried out using a Composite Central Design, with the most important factors for chitosanolytic activity (chitosan and FeSO4), in accordance with Plackett & Burman Design, and keeping the other nutrients in their minimum values. On this other design, it was taken the highest limit in Plackett & Burman Design as the lowest limit (-1) to FeSO4 factor. The results showed that the enzyme production was favoured by increasing the chitosan concentration and by decreasing FeSO4. Maximum production for chitosanolytic activity was about 70.0 U/L and was reached in only 18 h of fermentation, a result about twenty-eight times greater than a former study using the same microorganism (about 2.5 U/L at 48 h)

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The Brazilian caatinga is characterized by low annual rainfall and arid soils. Several cactaceae, either native or adapted species, grow in this semi-arid region, including the prickly pear (Opuntia fícus indica) and facheiro ((Philosocereus pachycladus Ritter) which produce underexploited edible fruits. In addition to these species, the algaroba is a leguminous with little studied technological applications and bioactive potential so far. Therefore, this research aims to investigate the physicochemical, bioactive and functional attributes of the prickly pear and facheiro fruit pulps and the algaroba flour. Specifically, this study approaches the physicochemical characterization, total phenolic compounds (TPC) and the betalain identification and quantification by HPLC-DAD-ESI-MS. It is also investigated the DPPH antioxidant capacity and the antienzymatic activities against alpha-amylase and alphaglucosidase of water and ethanolic extracts of these food material. In order to address their potential to be used as food ingredients, juice blends prepared with mixtures of cajá and prickly pear, biofilms with facheiro and cereal bars with algaroba flour were elaborated and analyzed. The prickly pear fruits presented low acidity and high sugar content when compared to facheiro. The Philosocereus pachycladus Ritter fruits had higher protein and ash content, but the algaroba flour was the species with higher protein and sugar content among all. The algaroba flour also presented outstanding food fiber content, which reveals its potentiality to be used as a natural intestinal regulator. The TPC of water and ethanol extracts ranged from 3.87 to 16.21 mg GAE/100g for algaroba flour, 79.24 to 110.20 GAE/ 100g for prickly pear and 412.23 to 539.14 mg GAE/100g for facheiro. The 70% (w/v) ethanol extract reached the highest DPPH antioxidant activity, which was linearly correlated to its high TPC content. In regard to the enzymatic inhibitory activities, the best performance was observed for the prickly pear extracts which presented a moderate inhibition for both investigated enzymes, but interestingly, no alpha-glucosidase inhibition was observed for facheiro extracts. This work shows, for the first time in the literature, the functional attributes of facheiro fruits, as well as the presence of betacianins and isobetanin in the pulp of this exotic fruit. When it comes to the food products developed here, the sensory attributes that better described the juice blend cajá-prickly pear were sweetness, acidity, color yellow-orange, body, turbidity and cajá flavor. The discriminative test applied for cereal bars produced with and without algaroba revealed that the texture was the only sensory attribute that differed (p<0.05) between these two samples. It was also observed that the addition of facheiro extracts did not influence the visual characteristics of the biofilms. Overall, this work unveils the physicochemical and bioactive attributes of these commercial and technologically underexploited species widely found in the Brazilian caatinga and presents alternatives for their rational use

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The groundwater represents the most important freshwater supply of planet. Dailly, in all world a great amount of toxic and genotoxic material reaches the aquatic systems, mainly the aquifers. The Barreiras aquifer through of five water wells is responsible for the supplying of Universidade Federal do Rio Grande do Norte (UFRN). All water wells are polluted with nitrate and some heavy metals, two of them were disabled. The genotoxicity of groundwater samples from Barreiras Aquifer in UFRN was assessed using the Allium cepa test, the Ames test and the Salmonella typhymurium microsuspension test (Kado test). For the Allium cepa test the influence of the groundwater samples collected on macroscopic (root length, colour and form) and microscopic (root tip mitotic index, chromosome aberrations and micronucleus) parameters was examined. All water samples caused a significant increase of the chromosome and mitotic aberration frequency and reduction on the rooth growth compared to negative control. Bridges and chromosome stickness were the most frequent kind of aberration in dividing cells. Furthermore, breaks were also observed. No significant increase in the number of micronuclei was found in relation to the negative controls. For Ames test were used the Salmonella typhymurium strains TA98 and TA100 without metabolic activation, applying the direct method. Prior to the Kado test, organic fractions from the water samples were obtained through XAD resin concentration. The mutagenicity organic extracts were evaluated by Kado test using TA98 and TA100 strains, in the absence and presence of S9 mix (metabolic activation). The concentrations of seven heavy metal ions were measured in water samples, but only Ni, Cu and Cr levels exceeded the permissible maximum concentration for the natural reservoirs. The results obtained for mutagenic activity using the Ames test were negative in all raw water samples analyzed. Positive results in XAD4 extracts of water samples were obtained for TA98 in the presence of S9 mix for two stations. Concentrations of heavy metals and nitrate can be correlated with the toxicity and genotoxicity of water analyzed. The mutagenic effect detected with TA98 strain suggested that organic compounds (after metabolization) are involved with the mutagenicity detected in the samples analyzed. The data set obtained in this work indicated the presence of at least two classes of mutagens: organic and inorganic compounds

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Conselho Nacional de Desenvolvimento Científico e Tecnológico

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The direct relationship with the processing, industrial yield and price of milk, the importance of the centesimal composition of milk and their protein fractions has increased for both the dairy industry and for the producers, so it is important to identify the possible causes on variation of these components. The aim of this study was to evaluate the effect of the seasons, order of calving and lactation phase on milk composition and protein fractions in dairy farms in the Agreste and Leste meso-regions, of Rio Grande do Norte State (RN). Milk samples were taken in seven milk farms directly from the bulk tanks except for one farm where samples were taken from higher milking cows producers and heifers. The experiment was done in seven properties with milk samples taken directly from the bulk tanks and in one property were collected from higher production cows and heifers. Composition analyses were carried out for both experiments and sensorial trial was performed for the second experiment only. The data results were submitted to analysis of variance (ANOVA) and Tukey test performed for 5% significance level. In the first experiment was observed response of the seasons, dry and rainy season; while in the second, the effect of the order of calving and lactation phase had influence on milk composition and protein fractions. There was significant response (p < 0.05) for season effects but due to farms. The rainy season had higher averages in the protein, lactose, total solids and nonfat dry extract. Multiparous cows had higher CCS, NUL and PCAS milk contents; while, first calving heifers showed higher average for the sensory attribute, color of milk. The final third of lactation was responsible for the elevation of the levels of almost all milk components and their protein fractions

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In this present work an ethnographic research was performed with 84 native medicinal specimens from the Litoral Norte Riograndense, from which two plants Cleome spinosa Jacq e Pavonia varians Moric were submitted to ethnobotanic, phytochemistry and pharmacologic investigations. Additionally, a phytopharmacological research of the medicinal specimen Croton cajucara Benth ( native plant of the Amazon region of Brazil) was improved. The obtained phytochemical results of the C. spinosa and P. varians showed the presence of flavonoids constituents, among other components. The two flavonoids (2S)-5-hydroxy-7,4 -dimethoxy-flavanone and 5,4 -dihydroxy-3,7,3 -trimethoxy-flavone were isolated from C. spinosa. The antioxidant activity of the hydroalcoholic extracts of C. spinosa and P. varians solubilized in the microemulsion systems SME-1 and SME-4, was evaluated in the DPPHmethod. The used SME systems [obtained with Tween 80: Span 20 (3:1) and isopropyl myristate (IPM)] improved the dissolution of those tested polar extracts, with higher efficacy to the SME-1 system (in which ethanol was included as cosurfactant). The CE50 values evidenced for P. varians were 114 [g/mL (SME-1) and 246 [g/mL (SME-4); for C. spinosa it was 224 [g/mL (SME-1) and 248 [g/mL (SME-4), being the system SME-1 more effective for both tested extracts. The hydroalcoholic extracts of P. varians (HAE-PV) was also submitted to pharmacological screening for antinociceptive activity in animal models. The oral administration of this extract (100, 300 and 1000 mg/kg) inhibited the acetic acid-induced writhing in mice. The higher inhibition (74%) was evidenced to the 1000 mg/kg administered dose. Its effect on the central nervous system (CNS) was investigated by tail flick and formalin-method and reveled that it has negligible antinociceptive action on the CNS. After taking consideration of HAE-PV interaction, Pavonia varians Moric could be used as a potent analgesic agent in case of peripheral algesia, without affecting the CNS. The phytochemical study of the stem bark of Croton cajucara Benth lead to the isolation of 19-nor-clerodanetype diterpenes, as well as to the separation of its fixed oil FO-CC. This non polar oil material reveled to be rich in sesquiterpenes and 19-nor-clerodanes components. The biologic effect of OF-CC was evaluated in the development in vitro of the fungis phytopatogens such as Fusarium oxysporum, Rhizoctonia solani and Sclerotium rolfsii. Significant inhibitory effect of the tested fungis (at 0,2 mg.mL-1 dosage) were comproved. A Mass Spectrometry study of clerodane-type diterpenes was developed in order to identify characteristic fragments on mass spectrometra of both clerodane and 19-nor-clerodane presenting an α,β-insaturated carbonyl moiety at ring A of the decalin-system. For that study, mass spectroscopy data were analysed for 19-nor-clerodanes [trans-dehydrocrotonin (DCTN), trans-crotonin (CTN), cis-cajucarin B (c-CJC-B), and cajucarinolide (CJCR)] and for clerodanes [isosacacarin (ISCR) and transcajucarin A (t-CJC-A)] obtained from the stem bark of C. cajucara, and also clerodane-type from other species. The trans-junction of the enone-system clerodanes was clear correlated with the presence of the characteristic ions at m/z 95, 121 e 205. Meanwhile, the characteristics ions at m/z 122 e 124 were correlated to cis-junction. The trans-junction of the enone-system 19-nor-clerodanes showed characteristics ions at m/z 161, 134 e 121. This study could be successful employed for identification of clerodane constituents from other specimens without any additional spectroscopic analyses, as well as a previously phytochemical analyzes in clerodane project search

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This study conducted chemical analyzes of the fruits of Licania tomentosa Benth belonging to the Chrysobalanaceae family, order and superorder Rosiflorae Rosales. Samples were collected in February 2011 in the city of Natal - RN. The fruits were separated into peel, pulp and seed, and the samples were analyzed on moisture and ash by thermogravimetric methods, reducing and total sugars, lipids by Soxhlet extraction, minerals by ICP / OES and other analyzes by physical measurements of the fruit. The fruits for the analysis of determination of flavonoids and phenolic compounds were dried at 40 ° C and ground. For the analyzes to determine the content of phenolics and flavonols was used spectroscopy in the visible region, and also performed the characterization of ethanol extracts by high performance liquid chromatography and test for antioxidant activity hydroethanolic extracts. The results obtained are about 83.9% of the fruits have a length between 4.0 to 6.0 cm with respect to the diameter of the fruit about 97.4% of the fruits have a diameter between 2.0 - 4, 0 cm, mean weight of 36.14 g (7.86), the bark showed 60.5 (1.5)% relative humidity, the flesh 72.3 (0.9) and 44.4 seeds (0.4 )%, the bark showed 0.22 (0.00)% ash, the pulp 1.41 (0.01)% and the seed 1.18 (0.01)%, the bark showed 3.73 (0, 09) mg lipids / 100 g sample of the pulp 0.40 (0.04) and the seed 0.05 (0.00). With respect to reducing sugars and total gave the results, 16.23 (0.23) g/100g and 20.70 (0.24) g/100g. The fruit is presented with a good source of nutrients especially carbohydrates and lipids. The analysis for determining the antioxidant activity tests were performed reducing power and antioxidant capacity, the antioxidant capacity of hydroethanolic extracts of peel and pulp showed similar results, with higher concentrations however hydroethanolic bark extract. Regarding the content of phenolics and flavonoids hidroetanílico bark extract showed higher concentration values. The characterization of the extracts by high performance liquid chromatography identified the following compounds by retention time indicated by the race of the standards: galic acid, kaempferol and kaempferol derivatives. Considering the results of the fruit Licania tomentosa Benth may be an alternative food by analysis of their nutritional content and has substances with antioxidant action

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Corrosion is a natural process that causes progressive deterioration of materials, so, reducing the corrosive effects is a major objective of development of scientific studies. In this work, the efficiency of corrosion inhibition on a AISI 1018 carbon steel of the nanoemulsion system containing the oil of the seeds of Azadirachta indica A. Juss (SNEOAI) was evaluated by the techniques of linear polarization resistance (LPR) and weight loss (CPM), a instrumented cell. For that, hydroalcoholic extract of leaves of A. indica (EAI) was solubilized in a nanoemulsion system (SNEOAI) of which O/W system (rich in aqueous phase). This nanoemulsion system (tested in different concentrations) was obtained with oil from the seeds of this plant species (OAI) (oil phase), dodecylammonium chloride (DDAC) (surfactant), butanol (cosurfactant) and water, using 30 % of C/T (cosurfactant/surfactant), 0.5 % of oil phase and 69.5 % of aqueous phase, and characterized by surface tension, rheology and droplet sizes. This systems SNEOAI and SNEOAI-EAI (nanoemulsion containing hydroalcoholic extract - EAI) showed inhibition efficiencies in corrosive environment in saline (1 %), for the method of LPR with significant value of 70.58 % (300 ppm) to SNEOAI, 74.17 % (100 ppm) and 72.51 % (150 ppm) to SNEOAI-EAI. The best efficiencies inhibitions were observed for the method of CPM with 85.41 % for the SNEOAI (300 ppm) and 83.19 % SNEOAI-EAI (500 ppm). The results show that this formulation could be used commercially for use as a corrosion inhibitor, this research contributed to the biotechnological applicability of Azadirachta indica, considering the large use of this plant species rich in limonoids (tetranortriterpenoids), especially azadirachtin

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Among the new drugs launched into the market since 1980, up to 30% of them belong to the class of natural products or they have semisynthetic origin. Between 40-70% of the new chemical entities (or lead compounds) possess poor water solubility, which may impair their commercial use. An alternative for administration of poorly water-soluble drugs is their vehiculation into drug delivery systems like micelles, microemulsions, nanoparticles, liposomes, and cyclodextrin systems. In this work, microemulsion-based drug delivery systems were obtained using pharmaceutically acceptable components: a mixture Tween 80 and Span 20 in ratio 3:1 as surfactant, isopropyl mirystate or oleic acid as oil, bidistilled water, and ethanol, in some formulations, as cosurfactants. Self-Microemulsifying Drug Delivery Systems (SMEDDS) were also obtained using propylene glycol or sorbitol as cosurfactant. All formulations were characterized for rheological behavior, droplet size and electrical conductivity. The bioactive natural product trans-dehydrocrotonin, as well some extracts and fractions from Croton cajucara Benth (Euphorbiaceae), Anacardium occidentale L. (Anacardiaceae) e Phyllanthus amarus Schum. & Thonn. (Euphorbiaceae) specimens, were satisfactorily solubilized into microemulsions formulations. Meanwhile, two other natural products from Croton cajucara, trans-crotonin and acetyl aleuritolic acid, showed poor solubility in these formulations. The evaluation of the antioxidant capacity, by DPPH method, of plant extracts loaded into microemulsions evidenced the antioxidant activity of Phyllanthus amarus and Anacardium occidentale extracts. For Phyllanthus amarus extract, the use of microemulsions duplicated its antioxidant efficiency. A hydroalcoholic extract from Croton cajucara incorporated into a SMEDDS formulation showed bacteriostatic activity against colonies of Bacillus cereus and Escherichia coli bacteria. Additionally, Molecular Dynamics simulations were performed using micellar systems, for drug delivery systems, containing sugar-based surfactants, N-dodecylamino-1-deoxylactitol and N-dodecyl-D-lactosylamine. The computational simulations indicated that micellization process for N-dodecylamino-1- deoxylactitol is more favorable than N-dodecyl-D-lactosylamine system.

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The environmental impact due to the improper disposal of metal-bearing industrial effluents imposes the need of wastewater treatment, since heavy metals are nonbiodegradable and hazardous substances that may cause undesirable effects to humans and the environment. The use of microemulsion systems for the extraction of metal ions from wastewaters is effective when it occurs in a Winsor II (WII) domain, where a microemulsion phase is in equilibrium with an aqueous phase in excess. However, the microemulsion phase formed in this system has a higher amount of active matter when compared to a WIII system (microemulsion in equilibrium with aqueous and oil phases both in excess). This was the reason to develop a comparative study to evaluate the efficiency of two-phases and three-phases microemulsion systems (WII and WIII) in the extraction of Cu+2 and Ni+2 from aqueous solutions. The systems were composed by: saponified coconut oil (SCO) as surfactant, n-Butanol as cosurfactant, kerosene as oil phase, and synthetic solutions of CuSO4.5H2O and NiSO4.6H2O, with 2 wt.% NaCl, as aqueous phase. Pseudoternary phase diagrams were obtained and the systems were characterized by using surface tension measurements, particle size determination and scanning electron microscopy (SEM). The concentrations of metal ions before and after extraction were determined by atomic absorption spectrometry. The extraction study of Cu+2 and Ni+2 in the WIII domain contributed to a better understanding of microemulsion extraction, elucidating the various behaviors presented in the literature for these systems. Furthermore, since WIII systems presented high extraction efficiencies, similar to the ones presented by Winsor II systems, they represented an economic and technological advantage in heavy metal extraction due to a small amount of surfactant and cosurfactant used in the process and also due to the formation of a reduced volume of aqueous phase, with high concentration of metal. Considering the reextraction process, it was observed that WIII system is more effective because it is performed in the oil phase, unlike reextraction in WII, which is performed in the aqueous phase. The presence of the metalsurfactant complex in the oil phase makes possible to regenerate only the surfactant present in the organic phase, and not all the surfactant in the process, as in WII system. This fact allows the reuse of the microemulsion phase in a new extraction process, reducing the costs with surfactant regeneration

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This study aimed to analyze the phytoremediation potential of Eichhornia crassipes in natural environments, optimize the extraction process of crude protein from plant tissue and, obtain and characterize this process in order to determine its viability of use instead of the protein sources of animal and/or human feed. For this, it has been determined in Apodi/Mossoró river water the concentration of ammonium ions, nitrite, nitrate, calcium, magnesium, potassium, iron, copper, manganese, zinc, nickel, cobalt, sodium, aluminum, cádmium, lead, and total chromium; It was determined in plant tissue of aquatic macrophytes of Eichhornia crassipes species present in Apodi/Mossoró River the moisture content, ash, calcium, magnesium, potassium, iron, copper, manganese, zinc, nickel, cobalt, sodium, aluminum, cadmium, lead, total chromium, total nitrogen and crude protein. It was also determined the translocation factor and bioaccumulation of all the quantified elements; It was developed and optimized the extraction procedure of crude protein based on the isoelectric method and a factorial design 24 with repetition; It was extracted and characterized the extract obtained by determining the moisture content, ash, magnesium, potassium, iron, copper, manganese, zinc, nickel, cobalt, sodium, cadmium, total nitrogen and crude protein. And finally, it was also characterized the protein extract using Thermogravimetric Analysis (TG), Derived Thermogravimetric (DTG), Differential Scanning Calorimetry (DSC), Infrared Spectroscopy (FT-IR) and jelly-like electrophoresis of polyacrylamide (SDS -PAGE) to assess the their molecular weights/mass. Thus, from the results obtained for the translocation and bioaccumulation factors was found that the same can be used as phytoremediation agent in natural environments of all quantified elements. It was also found that the developed method of extraction and protein precipitation was satisfactory for the purpose of the work, which gave the best conditions of extraction and precipitation of proteins as: pH extraction equal to 13.0, extraction temperature equals 60 ° C, reaction time equals to 30 minutes, and pH precipitation equals to 4.0. As for the extract obtained, the total nitrogen and crude protein were quantified higher than those found in the plant, increasing the crude protein content approximately 116.88% in relation to the quantified contente in the vegetal tissue of macrophyte. The levels of nickel and cadmium were the unique that were found below the detection limit of used the equipment. The electrophoretic analysis allowed us to observe that the protein extract obtained is composed of low polypeptide chains by the molecular and phytochelatins, with 6 and 15 kDa bands. Analysis of TG, DTG, DSC and FT-IR showed similarities in protein content of the obtained extracts based on different collection points and 9 parts of the plant under study, as well as commercial soy protein and casein. Finally, based on all these findings, it was concluded that the obtained extract in this work can be used instead of the protein sources of animal feed should, before that, test its digestibility. As human supplementation, it is necessary to conduct more tests associated with the optimization process in the sense of removing undesirable components and constant monitoring of the water body and the raw material used

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This study is about the users' experiences of the services offered by League Against Câncer that are in treatment of breast cancer, focusing on how the health/illness process develops. It is distinguished, in this context, the National Politics of Health, approaching the sprouting, implantation and consolidation process of the Unified Health System and its shocks on the installment of health services to the low-income population as a legit right from Citizen Constitution. It has as an objective to analyze how the social-economic extract of these women intervenes with such process, the aspects who involve the cancer while a pathology, approaching the signals, symptoms, forms of prevention, diagnosis, among other aspects that configure themselves as important points to the understanding of these experiences, since the diagnosis, treatment and control phases. The research was carried out with 25 women, between the months of January and February of year of 2005. The used technique was the scriptstructured interview, whose universe was defined through intentional sample. The following distinguishes as a result of the research: The majority of the women has its origins on the interior of the state, possesses a familiar income from one to three minimum wages and didn't make any kind of prevention before diagnosis, currently make treatment, beyond other aspects. It becomes necessary posterior studies on this social problematic, with respect to the personal, professional, familiar and social daily behavior of these women. It is worth mentioning that the role of the social assistant in the developed work with these women, understanding all the impediments associated with such experiences, as well as giving information about the rights of the patients with cancer, conquered through the years

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The current environmental crisis demands transformations in the relations among society, nature and development, considering sustainability. In this context, an important theme is replacing fossil fuels with biofuels, such as biodiesel. Moringa oleifera Lam. is a species that can be used as a raw material to produce biodiesel. Besides, it is a multiple purposes plant, which can be used also in water treatment. Thus, the aims of this work were to analyze the anatomical adaptations found in the stem and in the leaf and the seed s oil stores of M. oleifera., to investigate chemical characteristics of M. oleifera s seed oil, considering biodiesel production, and to evaluate the coagulation activity of these seeds in water treatment. Semipermanent histological laminas were made and it follows that the stem has thick cuticle, stomata whose cells guard are below the epidermis line, hollow medulla, druses and tector trichomes as adaptations to climate and soil conditions in which the species is found and the leaf is dorsiventral and it has thick cuticle, tector trichomes and druses. The seed has great reserves of oil. These features favor the use of Moringa oleifera Lam. as a raw material to produce biodiesel in Brazil s Northeast semiarid region. Chemical analysis were made through oil solvent extraction using mechanic stirrer. The oil was analyzed in UV spectrophotometer. A transesterification was made and biodiesel was analyzed in gas chromatography. Oil yield was high and good quality biodiesel was obtained. To evaluate seeds coagulantion activity, coagulation and flocculation essays in jartest were made, using seed extract to treat raw water. Seeds were efficient in cogulation process to treat water. So, they can be used in rudimentary systems or as a raw material to coagulant proteins extraction, as an alternative to traditional coagulants. M. oleifera has characteristics that favor its use to biodiesel production and water treatment

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The increase in the incidence of fungal infections due to the drug-resistance or to the number of patients with immune alterations such as AIDS, chemotherapy or organ transplantation, has done the research necesseray for new antifungal drugs. The species from Northeastern Brazil may become an important source of innovative natural molecules. To evaluate the antifungal activity of 10 medicinal plants from Northeastern Brazil, traditionally used as antimicrobial agents, 30 crude extracts (CE) were tested in vitro against four standard species of Candida spp. The CE most promising of these plants were evaluated against yeasts of the oral cavity of kidney transplant patients and through a bioassay-guided fractionation. The extracts form leaves of E. uniflora, the stem bark of L. ferrea and leaves of P. guajava showed significant activity against all yeasts evaluated, with MIC values between 15.62 and 62.5 μg/mL. E. uniflora also showed fungicidal properties against all yeasts, especially against Candida dubliniensis. In patients with immune systems compromised, such as transplanted, oral candidiasis manifests mainly due to immunosuppressive therapy, and resistance to conventional antifungals. The CE of E. uniflora presented range of MIC values between 1.95 to 1000 μg/mL, and lower MIC50 and MIC90 values were observed against C. non-albicans. Due the better results, the CE of E. uniflora was elected to performe the bioassay-guided fractionation. Thus it was possible to obtain enriched fractions, which showed good inhibitory ability against ATCC strains of Candida spp. It was also possible to perform experiments to verify the production of biofilm in two strains of C. dubliniensis and action of extracts and fractions on the same. With this, we observed a behavior between the yeast ATCC and clinical isolate. In addition, CE, fractions and subfractions of E. uniflora inhibit planktonic cells to preventing the growth of biofilm. The preliminary chemical characterization of the fractions obtained revealed the presence of polyphenols (especially flavonoids and tannins). Finally, the results suggests that among the plant species studied, E. uniflora showed a pattern very promising as regards the antifungal, requiring further study of purification and structural elucidation of compounds in order to verify that the antifungal effect found can be attributed to a specific compound or some mechanism depends on synergistic the mixture of polyphenols

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Fucans, sulfated polysaccharides extracted from brown algae and some echinoderms, have been extensively studied for its diverse biological activities and because of its interference with molecular mechanisms of cell to cell recognition, including leukocyte trafficking from blood vessels into sites of inflammation mediated by selectin, a family of adhesion molecules. In the present study, we examined structural features of a heterofucan extracted from brown algae Padina gymnospora and its effect on the leukocyte migration to the peritoneum. The sulfated polysaccharides were extracted from the brown seaweed by proteolysis with the proteolytic enzyme maxatase. The presence of protein and uronic acid contamination was detected in the crude polysaccharide extract. Fractionation of the crude extract with growing concentrations of acetone produced five fractions with different concentrations of fucose, xylose, uronic acid, galactose, glucose and sulfate. The fraction precipitated with 1.5 volumes of acetone was characterized by infrared and nuclear magnetic resonance, through which can be observed the presence of sulfate groups in the C4 of -L-fucose. The anti-inflammatory action of this composite was assessed by a sodium thioglycollate-induced peritonitis assay and through nitric oxide production by the peritoneal macrophages using Griess reagent. Fraction F1.5 was efficient in reducing leukocyte influx into the peritoneal cavity when 10 mg/kg and 25mg/kg were used, resulting in a decrease of 56 and 39%, respectively. A decrease of nitric oxide production occurred when high concentrations of fucana were used. The cytotoxicity of the composite was also assessed using the reduction of 3-(4,5 dimethylthiazol-2-yl) 2,5-diphenyltetrazolium bromide (MTT). Fraction F1.5 had no cytotoxicity when 500 μg/mL of the fraction was used. This study suggests the use of fraction F1.5 (heterofucan) as an anti-inflammatory