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1.
Environ Microbiol ; 21(3): 1019-1034, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30623562

RESUMO

Cocoyam (Xanthosoma sagittifolium (L.)), an important tuber crop in the tropics, is severely affected by the cocoyam root rot disease (CRRD) caused by Pythium myriotylum. The white cocoyam genotype is very susceptible while the red cocoyam has some field tolerance to CRRD. Fluorescent Pseudomonas isolates obtained from the rhizosphere of healthy red and white cocoyams from three different fields in Cameroon were taxonomically characterized. The cocoyam rhizosphere was enriched with P. fluorescens complex and P. putida isolates independent of the plant genotype. LC-MS and NMR analyses revealed that 50% of the Pseudomonas isolates produced cyclic lipopeptides (CLPs) including entolysin, lokisin, WLIP, putisolvin and xantholysin together with eight novel CLPs. In general, CLP types were linked to specific taxonomic groups within the fluorescent pseudomonads. Representative CLP-producing bacteria showed effective control against CRRD while purified CLPs caused hyphal branching or hyphal leakage in P. myriotylum. The structure of cocoyamide A, a CLP which is predominantly produced by P. koreensis group isolates within the P. fluorescens complex is described. Compared with the white cocoyam, the red cocoyam rhizosphere appeared to support a more diverse CLP spectrum. It remains to be investigated whether this contributes to the field tolerance displayed by the red cocoyam.


Assuntos
Proteínas de Bactérias/genética , Lipopeptídeos/genética , Peptídeos Cíclicos/genética , Pseudomonas fluorescens/genética , Xanthosoma/microbiologia , Fluorescência , Variação Genética , Pseudomonas fluorescens/isolamento & purificação , Pythium , Rizosfera
2.
J Texture Stud ; 50(2): 148-154, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30548624

RESUMO

Growing interest in processed frozen products with similar characteristics to natural products has generated the study of new products in the food industry field. The characteristics of each matrix, the process of elaboration, composition, and structure of the additives and the interactions amongst these modify the food's texture, structure, physical and sensory properties and, hence, interfere directly with consumer acceptance. This research studied the effect of adding cryoprotectors during frozen storage on the rheological, physicochemical, structural, and microbiological properties in a Mafafa-quinoa-olive oil puree. To carry out the study, the rheological properties were determined through dynamic oscillatory tests and in steady state; likewise, the physicochemical properties (humidity, color, pH, and syneresis) were analyzed. Regarding physicochemical properties, the humidity content in the purees formulated varied between 57 and 74%, without important variation (p > .05) with respect to the formulation, however, in the storage during the freezing/thawing process, this parameter diminished in greater proportion in those purees containing carrageenan as cryoconservant. Both the addition of cryoconservants and the storage time affected significantly (p < .05) the puree's syneresis, with the degree of exudation being lower in the formulation containing xanthan gum at 1% w/w. During the freezing/thawing process, decreased apparent viscosity was noted. Additionally, the analysis of the viscoelastic properties of the purees evidences that already described, given that a significant effect (p < .05) was observed of the formulation of purees in the elastic component G', in contrast with a notable decrease in the viscous component G″.


Assuntos
Fenômenos Químicos , Chenopodium quinoa/química , Crioprotetores/farmacologia , Reologia , Xanthosoma/química , Aditivos Alimentares/farmacologia , Manipulação de Alimentos/métodos , Microbiologia de Alimentos , Congelamento , Azeite de Oliva/química , Polissacarídeos Bacterianos , Viscosidade
3.
Environ Sci Pollut Res Int ; 25(36): 35949-35959, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29796887

RESUMO

During last decades, there has been a growing interest of decreasing the environmental impact generated by humans. This situation has been approached from different perspectives being the integral use of raw materials as one of the best alternatives. It was estimated that 3.7 × 109 tonnes of agricultural residues are produced annually worldwide. Then, the integral use of feedstocks has been studied through the biorefinery concept. A biorefinery can be a promissory option for processing feedstocks in rural zones aiming to boost the techno-economic and social growth. However, many plants produced at small scale in rural zones without high industrial use contribute with residues usually not studied as raw materials for other processes. Cocoyam (Xanthosoma sagittifolium) is a plant grown extensively in tropical regions. Nigeria, China, and Ghana are the main producers with 1.3, 1.18, and 0.9 million tonnes/year, respectively. In Colombia, there are no technified crops, but it is used where it is grown mainly as animal feed. This plant consists of leaves, stem, and a tuber but the use is generally limited to the leaves, discarding the other parts. These discarded parts have great potential (lignocellulose and starch). This work proposes different processing schemes using the parts of the plant to obtain value-added products, and their techno-economic and environmental assessment. The simulation was performed with Aspen Plus and the economic package was used for the economic assessment. For the environmental assessment, Waste Algorithm Reduction of the U.S. EPA was implemented. The obtained results showed that the integral use of plants under a biorefinery scheme allows obtaining better techno-economic and environmental performance and that small-scale biorefineries can be a promissory option for boosting rural zones.


Assuntos
Ração Animal , Produtos Agrícolas , Resíduos Sólidos , Amido , Xanthosoma , Agricultura , Animais , Celulose , China , Colocasia , Colômbia , Meio Ambiente , Gana , Humanos , Resíduos Industriais , Nigéria , Folhas de Planta
4.
An Acad Bras Cienc ; 90(2): 1775-1787, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29694497

RESUMO

The objective of this study was to characterize the nutritional compounds of interest present in vegetables known as non-conventional, in Brazil. The following evaluations were carried out: antioxidant activity, phenolic compounds, vitamin C, calories, carbohydrates, humidity, lipids, proteins, fiber, acidity and quantification of minerals (P, K, Ca, Mg, S, Cu, Fe, Mn, Zn and B). The species studied were Amaranthus hybridus L., Amaranthus viridis L., Basella alba L., Eryngium campestre L., Hibiscus sabdariffa L., Lactuca canadensis L., Rumex acetosa L., Stachys byzantina K. Koch, Tropaeolum majus L. and Xanthosoma sagittifolium L. Representative samples of plant structures of interest were harvested from each species suitable for human consumption such as leaves, flowers and flower buds. The results were submitted to multivariate analysis - principal components analysis (PCA). All the species present nutritional compounds of interest in different levels among the evaluated structures.


Assuntos
Flores/química , Magnoliopsida/química , Valor Nutritivo , Brotos de Planta/química , Verduras/química , Amaranthus/química , Antioxidantes/metabolismo , Ácido Ascórbico/análise , Brasil , Caryophyllales/química , Fibras na Dieta/análise , Eryngium/química , Hibiscus/química , Minerais/análise , Fenóis/análise , Folhas de Planta/química , Rumex/química , Stachys/química , Tropaeolum/química , Xanthosoma/química
5.
Environ Monit Assess ; 189(4): 186, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28349313

RESUMO

The growing population number and traffic loads, increasing environmental pressures, agricultural intensification, and the establishment of Mount Cameroon National Park demand farsighted environmental management in the region and the definition of a favorable ecological status. Since plants grow in the interface between soils and the atmosphere they can be used as passive biomonitors for the environmental quality. At the same time, the accumulation of nutrients and pollutants in crops is linked to human health, so that foliar elemental levels can be used as an integrative measure for environmental pollution and impact assessment. In the present study, we collected leaf samples of plantain, cassava, cocoyam, and maize on 28 sites at the southern flanks of Mt. Cameroon and determined 20 chemical elements. Air pollution in the study area comes from biomass and waste burning mainly, but emissions from traffic and a large refinery were believed to also play a significant role. However, spatial patterns in foliar elemental concentrations reflected the geochemistry rather than specific sources of pollution. Significant differences in foliar metal and nutrient levels were observed between the four species, indicating a different demand and uptake of specific elements. The results were compared to published data on nutrient concentrations in the tested species and the so-called reference plant. The data can be used as a baseline for future studies in plant nutrition and the environmental monitoring in inner tropical regions where these crops are grown.


Assuntos
Produtos Agrícolas/metabolismo , Poluentes Ambientais/metabolismo , Metais/metabolismo , Folhas de Planta/química , Camarões , Monitoramento Ambiental , Manihot , Musa , Xanthosoma , Zea mays
6.
Drug Res (Stuttg) ; 67(6): 337-342, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28288491

RESUMO

The management of diabetes mellitus (DM) targets glycemic control as well as prevention or reversal of other complications associated with the metabolic disorder. One of such complications is the infertility which has been traced to oxidative stress and DNA damage caused by DM. In this study, experimentally-induced diabetic male Wistar rats were fed with Xanthosoma sagittifolium (cocoyam) for 14 days and its effect on sperm morphology and characteristics, as well as histology of the testes were assessed. X. sagittifolium corm feed (Xs) were reconstituted with commercial rat feed to contain 25, 50, 75 or 100% X. sagittifolium on a weight/weight basis. One primary and 7 secondary cell abnormalities were observed with overall increased total abnormal sperm cells in the diabetic rats. Sperm cell motility was significantly (p<0.05) reduced in all diabetic rats, but diabetic rats fed with Xs showed increased motility and liveability. Sperm volume was unchanged, but the depressed sperm count in the untreated diabetic rats was increased in Xs-fed rats. Histology of Xs-fed diabetic rats showed reduction in seminiferous tubule diameter and luminal diameter which was significantly enlarged in untreated diabetic rats. X. sagittifolium significantly (p<0.05) prevented further deterioration of sperm cell quality and reversed cell apoptosis as presented by increased sperm motility, liveability and count. In the overall, the chances of fertilization by sperm cells from diabetic patients will be increased as well as achievement of good glycemic control and prevention of further damage by the disease condition.


Assuntos
Diabetes Mellitus Experimental/tratamento farmacológico , Genitália Masculina/efeitos dos fármacos , Preparações de Plantas/farmacologia , Xanthosoma/química , Aloxano , Animais , Glicemia/efeitos dos fármacos , Dano ao DNA/efeitos dos fármacos , Diabetes Mellitus Experimental/complicações , Relação Dose-Resposta a Droga , Masculino , Medicina Tradicional , Estresse Oxidativo/efeitos dos fármacos , Preparações de Plantas/administração & dosagem , Ratos , Ratos Wistar , Motilidade Espermática/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos , Espermatozoides/metabolismo , Testículo/efeitos dos fármacos
7.
J Complement Integr Med ; 14(2)2017 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-28306532

RESUMO

Background Hematological and biochemical changes associated with diabetes mellitus and probable reversal were assessed in alloxan-induced diabetic Wistar rats fed with varied percentages of Xanthosoma sagittifolium corm feed (Xs). The changes were compared to normoglycemic rats and diabetic rats treated with glibenclamide. Methods The study had eight groups in all with group 8 (control) consisting of five normoglycemic rats fed with normal rat pellets (Nrp). Diabetes was experimentally induced by intraperitoneal injection of alloxan to normoglycemic rats. Diabetic rats (serum glucose >200 mg/dL) at 48 h postinjection were randomly divided into the seven groups, each diabetic group consisting of five rats. One group was untreated and fed with Nrp, four groups were fed with 25 %, 50 %, 75 % or 100 % Xs, one group was fed with 100 % Xs and administered with glibenclamide, while a 7th group was fed with Nrp and administered with glibenclamide. Results This study shows that treatment of diabetes with corm of X. sagittifolium increases cellular response to inflammation which is required for body defense against assaulting agents. Decreased serum protein levels observed in untreated diabetic rats were restored in diabetic rats fed with X. sagittifolium corm with particular increase in serum albumin levels but depression of globulin fraction, except in rats fed with X. sagittifolium feed and administered with glibenclamide. X. sagittifolium showed a potent antihyperglycemic effect and corrected the dyslipidemia in a manner comparable to that observed for glibenclamide. Although HDL levels were still low, significant (p<0.05) decrease of LDL levels was a positive indicator of reduced risk for development of cardiovascular and/or coronary heart disease. Conclusions X. sagittifolium corm can be recommended for inclusion in diets of diabetics without causing further deterioration of health of the diabetic patients.


Assuntos
Glicemia/metabolismo , LDL-Colesterol/sangue , Diabetes Mellitus Experimental/sangue , Hipoglicemiantes/farmacologia , Hipolipemiantes/farmacologia , Extratos Vegetais/farmacologia , Xanthosoma , Animais , HDL-Colesterol/sangue , Diabetes Mellitus Experimental/dietoterapia , Dislipidemias/sangue , Dislipidemias/dietoterapia , Globulinas/metabolismo , Glibureto/farmacologia , Glibureto/uso terapêutico , Hipoglicemiantes/uso terapêutico , Hipolipemiantes/uso terapêutico , Inflamação/dietoterapia , Fitoterapia , Extratos Vegetais/uso terapêutico , Tubérculos , Ratos Wistar , Albumina Sérica/metabolismo
8.
BMC Complement Altern Med ; 16: 9, 2016 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-26753836

RESUMO

BACKGROUND: The present study was designed to investigate the antibacterial activities of the methanol extract of three edible plants, namely Xanthosoma mafaffa, Moringa oleifera and Passiflora edulis and their synergistic effects with some commonly used antibiotics against MDR Gram-negative bacteria expressing active efflux pumps. METHODS: Broth microdilution method was used to determine the minimum inhibitory concentrations (MICs) and the minimum bactericidal concentrations (MBCs) of the extracts, as well as those of antibiotics in association with the extracts. RESULTS: The phytochemical test indicate that all tested crude extracts contained polyphenols, triterpenes and steroids whilst other phytochemical classes were selectively distributed. Extracts showed antibacterial activities with minimum inhibitory concentrations ranging from 128-1024 µg/mL on the majority of the 19 tested Gram-negative bacterial strains. Extract from the pericarp of P. edulis inhibited the growth of 89.5% of the 19 tested bacterial strains, the lowest minimal inhibitory concentration (MIC) value of 128 µg/mL being recorded against Escherichia coli AG100 strain. In the presence of Phenylalanine-Arginine ß-Naphtylamide (PAßN)], an efflux pump inhibitor (EPI), the activity of the extract from X. mafaffa increased on 40% of tested strains. In combination with antibiotics, extracts of X. mafaffa, M. oleifera and pericarp of P. edulis showed synergistic effects with some antibiotics against more than 75% of the tested bacteria. CONCLUSION: The results of the present study indicate that the tested plants may be used in the treatment of bacterial infections including the multi-resistant bacteria.


Assuntos
Antibacterianos/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Moringa oleifera , Passiflora , Extratos Vegetais/farmacologia , Xanthosoma , Colorimetria , Farmacorresistência Bacteriana Múltipla , Sinergismo Farmacológico , Testes de Sensibilidade Microbiana , Moringa oleifera/química , Passiflora/química , Plantas Comestíveis/química , Xanthosoma/química
9.
BMC Complement Altern Med ; 14: 335, 2014 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-25216815

RESUMO

BACKGROUND: Xanthosoma violaceum is commonly observed in fallow areas of Bangladesh but almost no scientific studies exist on this plant. Rural people consume the plant on a frequent basis. The objective of this study was to scientifically analyze the antinociceptive property of methanol extract of aerial parts of the plant along with antihyperglycemic activity. METHODS: Antihyperglycemic activity was measured by oral glucose tolerance test (OGTT). Antinociceptive activity was determined by observed decreases in abdominal constrictions in intraperitoneally administered acetic acid-induced pain model in mice. RESULTS: Administration of methanol extract of aerial parts led to dose-dependent and significant reductions in blood glucose levels in glucose-loaded mice. At doses of 50, 100, 200 and 400 mg per kg body weight, the extract reduced blood sugar levels by 19.3, 23.2, 31.8, and 47.1%, respectively compared to control animals. By comparison, a standard antihyperglycemic drug, glibenclamide, when administered at a dose of 10 mg per kg body weight, reduced blood glucose level by 48.9%. In antinociceptive activity tests, the extract at the above four doses reduced the number of abdominal constrictions by 41.4, 44.8, 48.3, and 55.2%, respectively. A standard pain relieving (antinociceptive) drug, aspirin, reduced the number of writhings by 31.0 and 51.7%, respectively, when administered at doses of 200 and 400 mg per kg body weight. CONCLUSION: To our knowledge, this is the first report on oral glucose tolerance and antinociceptive activity evaluation of aerial parts of the plant. Since the plant is widely available in Bangladesh, the aerial parts can be a readily available source for particularly the rural population for lowering blood sugar in diabetic patients and for alleviating pain.


Assuntos
Analgésicos/administração & dosagem , Diabetes Mellitus/tratamento farmacológico , Hipoglicemiantes/administração & dosagem , Dor/tratamento farmacológico , Extratos Vegetais/administração & dosagem , Xanthosoma/química , Analgésicos/isolamento & purificação , Animais , Glicemia/metabolismo , Diabetes Mellitus/metabolismo , Teste de Tolerância a Glucose , Humanos , Hipoglicemiantes/isolamento & purificação , Masculino , Camundongos , Componentes Aéreos da Planta/química , Extratos Vegetais/isolamento & purificação
10.
Int J Biol Macromol ; 65: 222-8, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24463263

RESUMO

This work presents the physicochemical and pasting characterization of isolated mafafa starch and mafafa flour (Xanthosoma robustum). According to SEM images of mafafa starches in the tuber, these starches form Lego-like shaped structures with diameters between 8 and 35 µm conformed by several starch granules of wedge shape that range from 2 to 7 µm. The isolated mafafa starch is characterized by its low contents of protein, fat, and ash. The starch content in isolated starch was found to be 88.58% while the amylose content obtained was 35.43%. X-ray diffraction studies confirm that isolated starch is composed mainly by amylopectin. These results were confirmed by differential scanning calorimetry and thermo gravimetric analysis. This is the first report of the molecular parameters for mafafa starch: molar mass that ranged between 2×10(8) and 4×10(8) g/mol, size (Rg) value between 279 and 295 nm, and molecular density value between 9.2 and 9.7 g/(mol nm(3)). This study indicates that mafafa starch shows long chains of amylopectin this fact contributes to higher viscosity development and higher gel stability. The obtained gel phase is transparent in the UV-vis region. The viscosity, gel stability and optical properties suggest that there is potential for mafafa starch applications in the food industry.


Assuntos
Fenômenos Químicos , Reologia , Amido/química , Xanthosoma/química , Amilopectina/análise , Amilose/análise , Farinha/análise , Fenômenos Ópticos , Temperatura
11.
J Food Sci ; 78(12): H1929-34, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24266602

RESUMO

Several studies have shown that fruits and vegetables contribute to protect against degenerative pathologies such as cardiovascular diseases, diabetes, and cancer, mainly due to the presence of dietary fiber (DF) and polyphenols. Taioba (Xanthosoma sagittifolium) is an edible aroid widely grown in many parts of Africa, America, and Asia. The tubers portions of taioba are widely consumed; however, the leafy portions are generally discarded, despite their high nutritive value. In this study, we have partly characterized the DF of lyophiized taioba leaf (LTL), and assessed the possible protective effects on biochemical parameters and on bile acid (BA) production in colon and cecum, when fed to healthy rats for 4 wk. Forty-five Wistar rats were assigned to either of 5 groups: group 1 received AIN 93G diet (CG: Control); group 2 received AIN 93G containing 2.5% of cellulose + 2.5% inulin (CEIN_5%); group 3 received AIN 93G containing 2.5% of cellulose + 2.5% taioba fiber (CETA_5%); group 4 received AIN 93G containing 5% cellulose + 2.5% taioba fiber (CETA_7.5%); group 5 received AIN 93G containing 5% cellulose + 2.5% of inulin (CEIN_7.5%). LTL showed high contents of total fiber, predominantly comprising insoluble DF with glucose as the major monomer. Rats receiving LTL had increased fecal mass and fat excretion, and improved BA profiles by diminishing the proportion of secondary acids, thus suggesting that consumption of taioba leaf may have the property of lowering the risk of colon cancer.


Assuntos
Compostos Fitoquímicos/farmacologia , Folhas de Planta/química , Xanthosoma/química , Animais , Ácidos e Sais Biliares/metabolismo , Ceco/metabolismo , Celulose/análise , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Colo/metabolismo , Fezes/química , Insulina/sangue , Inulina/análise , Valor Nutritivo , Ratos , Ratos Wistar , Triglicerídeos/sangue
12.
Food Sci Technol Int ; 19(4): 343-50, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23729419

RESUMO

Biscuits were produced from blends of pigeon pea, sorghum and cocoyam flours. The study was carried out using mixture response surface methodology as the optimization technique. Using the simplex centroid design, 10 formulations were obtained. Protein and sensory quality of the biscuits were analyzed. The sensory attributes studied were appearance, taste, texture, crispness and general acceptability, while the protein quality indices were biological value and net protein utilization. The results showed that while the addition of pigeon pea improved the protein quality, its addition resulted in reduced sensory ratings for all the sensory attributes with the exception of appearance. Some of the biscuits had sensory ratings, which were not significantly different (p > 0.05) from biscuits made with wheat. Rat feeding experiments indicated that the biological value and net protein utilization values obtained for most of the biscuits were above minimum recommended values. Optimization suggested biscuits containing 75.30% sorghum, 0% pigeon pea and 24.70% cocoyam flours as the best proportion of these components. This sample received good scores for the sensory attributes.


Assuntos
Pão/análise , Cajanus , Sorghum , Xanthosoma , Animais , Proteínas na Dieta , Farinha , Manipulação de Alimentos/métodos , Humanos , Masculino , Valor Nutritivo , Ratos , Ratos Wistar , Sementes , Sensação , Triticum
13.
ScientificWorldJournal ; 2012: 346595, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22666109

RESUMO

Sprouted corm sections of "South Dade" white cocoyam were potted and maintained in a greenhouse for 8 weeks. Shoot tips of 3-5 mm comprising the apical meristem with 4-6 leaf primordial, and approximately 0.5 mm of corm tissue at the base. These explants were treated to be used into the culture medium. A modified Gamborg's B5 mineral salts supplemented with 0.05 µM 1-naphthaleneacetic acid (NAA) were used throughout the study. Thidiazuron (TDZ) solution containing 0.01% dimethyl sulfoxide (DMSO) was used. Erlenmeyer flasks and test tubes were used for growing cultures. The effect of different media substrate, thidiazuron, and the interaction between TDZ and Benzylaminopurine (BAP) on cocoyam culture were tested. Results indicated that cocoyam can be successfully micropropagated in vitro through various procedures. All concentrations tested (5-20 µM BAP and 1-4 µM TDZ) produced more axillary shoots per shoot tip than the control without cytokinins. Greater proliferation rates were obtained through the use of 20 µM BAP and 2 µM TDZ, respectively, 12 weeks from initiation. Shoots produced with BAP were larger and more normal in appearance than those produced with TDZ, which were small, compressed, and stunted. The use of stationary liquid media is recommended for economic reasons.


Assuntos
Xanthosoma/metabolismo , Meios de Cultura , Dimetil Sulfóxido/química , Técnicas In Vitro , Ácidos Naftalenoacéticos/química , Brotos de Planta/crescimento & desenvolvimento
14.
Pharm Biol ; 50(7): 930-2, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22468879

RESUMO

CONTEXT: Xanthosoma sagittifolium Schott. (Araceae) and Laportea aestuans (L.) Chew (Urticaceae) are two medicinal species used as food and to prevent and treat bone diseases, such as osteoporosis, in traditional Brazilian medicine. OBJECTIVE: To investigate the free calcium concentration and further support the traditional use of these species as medicine. MATERIALS AND METHODS: L. aestuans and X. sagittifolium leaves were dehydrated and cooked to evaluate the presence of free calcium. The total oxalate content was determined by heat digestion in H(2)SO(4), oxalate precipitation with CaCl(2) and permanganate titration. RESULTS: The calcium content found in L. aestuans was quite significant (638.00 mg/100 g), whereas the fresh and cooked leaves of X. sagittifolium demonstrated a low content of calcium, at 273.17 and 369.81 mg/100 g, respectively. DISCUSSION AND CONCLUSION: The use of this species for the prevention and treatment of bone diseases is in agreement with the results of the free calcium (Ca(++)) analyses. Our data show that each species may be used as a health supplement in poor communities, provided that studies validate their safe use.


Assuntos
Medicina Tradicional/métodos , Osteoporose/prevenção & controle , Folhas de Planta/química , Urticaceae , Xanthosoma , Brasil/etnologia , Cálcio/uso terapêutico , Osteoporose/etnologia , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/uso terapêutico , Especificidade da Espécie
15.
J Nat Prod ; 74(5): 969-75, 2011 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-21520894

RESUMO

Bacterial infections directly affect the world's population, and this situation has been aggravated by indiscriminate use of antimicrobial agents, which can generate resistant microorganisms. In this report, an initial screening of proteins with antibacterial activity from corms of 15 species of the Xanthosoma genus was conducted. Since Xanthosoma blandum corms showed enhanced activity toward bacteria, a novel protein with bactericidal activity was isolated from this particular species. Edman degradation was used for protein N-termini determination; the primary structure showed similarities with Kunitz inhibitors, and this protein was named Xb-KTI. This protein was further challenged against serine proteinases from different sources, showing clear inhibitory activities. Otherwise, no hemolytic activity was observed for Xb-KTI. The results demonstrate the biotechnological potential of Xb-KTI, the first proteinase inhibitor with antimicrobial activity described in the Xanthosoma genus.


Assuntos
Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Peptídeos/isolamento & purificação , Peptídeos/farmacologia , Proteínas de Plantas/isolamento & purificação , Proteínas de Plantas/farmacologia , Xanthosoma/química , Sequência de Aminoácidos , Antibacterianos/química , Testes de Sensibilidade Microbiana , Peptídeos/química , Proteínas de Plantas/química , Serina Endopeptidases/metabolismo , Xanthosoma/genética
17.
Res Microbiol ; 161(6): 464-71, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20457252

RESUMO

The highly diverse genus Pseudomonas contains very effective biocontrol agents that can increase plant growth and improve plant health. Biocontrol characteristics, however, are strain-dependent and cannot be clearly linked to phylogenetic variation. Isolate screening remains essential to find suitable strains, which can be done by testing large local collections for disease suppression and plant-growth promotion exemplified in a case study on forage legumes in Uruguay or by targeted screening for Pseudomonas spp. which produce desirable secondary metabolites, as demonstrated in a case study on cocoyam in Cameroon. In both case studies, access to reference strains from public and private collections was essential for identification, phylogenetic studies and metabolite characterization.


Assuntos
Antifúngicos/metabolismo , Fabaceae , Controle Biológico de Vetores , Doenças das Plantas/prevenção & controle , Pseudomonas/metabolismo , Xanthosoma , Agricultura , Biodiversidade , Bancos de Espécimes Biológicos/estatística & dados numéricos , Camarões , Fabaceae/crescimento & desenvolvimento , Fluorescência , Doenças das Plantas/microbiologia , Raízes de Plantas/microbiologia , Pseudomonas/classificação , Pythium/crescimento & desenvolvimento , Pythium/patogenicidade , Uruguai , Xanthosoma/crescimento & desenvolvimento
18.
Water Sci Technol ; 60(12): 3253-9, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19955650

RESUMO

Trickling filters were used to treat wash water from a wood gasifier. This wash water contained toxic substances such as ammonium, cyanide, phenols, and PAH. The goal was to develop a system that degraded toxic substances, and achieved full nitrification of ammonia. A 1 kW model wood gasifier plant delivered wash water for the experiments, which was standardised to a conductivity of 3 mS/cm by dilution. Toxicity was assessed by bacterial luminescence detection, germination test with cress (Lepidium sativum), and pot plants cultivated in a hydroponic setup irrigated continuously with the wastewater. Treatment experiments were done in both planted and unplanted trickling filters. Plant yield was similar to conventional hydroponic production systems. The trickling filters achieved complete detoxification of phenol, PAH and cyanide as well as full nitrification. The specific elimination rates were 100 g m(-3) Leca d(-1) for phenols and 90 g m(-3) Leca d(-1) for ammonium in planted systems. In unplanted trickling filters circulated for 63 h, phenol concentration decreased from 83.5 mg/L to 2.5 mg/L and cyanide concentration from 0.32 mg/L to 0.02 mg/L. PAH concentrations were reduced from 3,050 microg/L to 0.89 microg/L within 68 days. The assays demonstrated the feasibility of using the technique to construct a treatment system in a partially closed circulation for gasifier wash water. The principal advantage is to convert toxic effluents from biomass gasifiers into a non-toxic, nitrogen-rich fertiliser water, enabling subsequent use in plant production and thus income generation. However, the questions of long-term performance and possible accumulation of phenols and heavy metals in the produce still have to be studied.


Assuntos
Amônia/análise , Biocombustíveis , Cianetos/análise , Fenóis/análise , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Amônia/química , Amônia/toxicidade , Biodegradação Ambiental , Biocombustíveis/análise , Biomassa , Carica/efeitos dos fármacos , Carica/crescimento & desenvolvimento , Conservação dos Recursos Naturais , Cianetos/química , Cianetos/toxicidade , Cyperus/efeitos dos fármacos , Cyperus/crescimento & desenvolvimento , Filtração , Lepidium sativum/efeitos dos fármacos , Lepidium sativum/crescimento & desenvolvimento , Fenóis/química , Fenóis/toxicidade , Hidrocarbonetos Policíclicos Aromáticos/análise , Hidrocarbonetos Policíclicos Aromáticos/química , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Testes de Toxicidade , Poluentes Químicos da Água/química , Purificação da Água/instrumentação , Áreas Alagadas , Xanthosoma/efeitos dos fármacos , Xanthosoma/crescimento & desenvolvimento
19.
Arch Virol ; 154(1): 159-62, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19034605

RESUMO

Dasheen mosaic virus (DsMV) is an important constraint to production of cocoyam (Xanthosoma spp.) in Nicaragua. Reverse transcription polymerase chain reaction was used to amplify the coat protein (CP) region from ten Nicaraguan DsMV isolates. These isolates showed high nucleotide identity to DsMV isolates from the USA, eastern Asia and Australasia. All Nicaraguan isolates except one shared a tandem repeat in the N-terminus of the CP. Phylogenetic analyses showed that the Nicaraguan isolates formed two distinct subgroups correlated with geographic origin. This can be explained by different origins of the cocoyam genotypes grown in these regions.


Assuntos
Potyvirus/genética , Xanthosoma/virologia , Proteínas do Capsídeo/genética , Dados de Sequência Molecular , Nicarágua , Filogenia , Folhas de Planta/virologia , Potyvirus/isolamento & purificação , RNA Viral/genética
20.
Environ Microbiol ; 10(3): 778-88, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18237310

RESUMO

In this study, the putative role of phenazines and rhamnolipid-biosurfactants, antagonistic metabolites produced by Pseudomonas aeruginosa PNA1, was tested in the biological control of Pythium splendens on bean (Phaseolus vulgaris L) and Pythium myriotylum on cocoyam (Xanthosoma sagittifolium L Schott). A rhamnolipid-deficient and a phenazine-deficient mutant of PNA1 were used either separately or jointly in plant experiments. When the mutants were applied separately, no disease-suppressive effect was observed, although both mutants still produced one of the antagonistic compounds (phenazines or rhamnolipids). When the mutants were concurrently introduced in the soil, the biocontrol activity was restored to wild-type levels. Bean seeds developed significantly less pre-emergence damping-off caused by P. splendens when treated with a mixture of purified phenazine-1-carboxamide and rhamnolipids than with any of the chemicals alone. When phenazines and rhamnolipids were combined at concentrations that had no observable effects when the metabolites were applied separately, mycelial growth of P. myriotylum was significantly reduced. In addition, microscopic analysis revealed substantial vacuolization and disintegration of Pythium hyphae after incubation in liquid medium amended with both metabolites. Results of this study indicate that phenazines and biosurfactants are acting synergistically in the control of Pythium spp.


Assuntos
Glicolipídeos/farmacologia , Controle Biológico de Vetores , Fenazinas/farmacologia , Doenças das Plantas/microbiologia , Pythium/efeitos dos fármacos , Phaseolus/microbiologia , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/metabolismo , Pythium/crescimento & desenvolvimento , Pythium/patogenicidade , Microbiologia do Solo , Xanthosoma/microbiologia
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