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1.
Food Chem ; 285: 119-129, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-30797326

RESUMO

Mango byproducts, such as peels, contain high levels of antioxidants and fiber and represent important sources of nutraceuticals and pharmacological products. Fruit are collected at the mature green stage then stored and ripened, undergoing several structural and molecular changes over the course of this process. However, very little is known regarding the content and nature of antioxidant compounds in peels of elite and local cultivars during postharvest shelf life (PSL). We screened the phenolic compound content of six cultivars during PSL, including elite (Kent, Tommy, and Ataulfo) and local (Manila, Manililla, and Criollo) mangoes, using a targeted metabolomics approach. We determined that Ataulfo mangoes exhibited the highest content of phenolic compounds during PSL. Untargeted metabolomics and comparative proteomics in Ataulfo and Manililla showed these cultivars to be significant sources of phenolic and lipidic compounds, with the latter cultivar also representing an interesting candidate as a new source for nutraceutical products.


Assuntos
Antioxidantes/química , Mangifera/química , Ácido Abscísico/análise , Aminoácidos Cíclicos/análise , Cromatografia Líquida de Alta Pressão , Frutas/química , Frutas/metabolismo , Mangifera/metabolismo , Espectrometria de Massas , Fenóis/análise , Filipinas , Extratos Vegetais/química , Extratos Vegetais/metabolismo , Proteínas de Plantas/análise , Proteínas de Plantas/isolamento & purificação , Proteínas de Plantas/metabolismo , Análise de Componente Principal , Proteômica
2.
Plant Biol (Stuttg) ; 20(3): 490-496, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29350442

RESUMO

Induced systemic resistance (ISR) is one of the indirect mechanisms of growth promotion exerted by plant growth-promoting bacteria, and can be mediated by ethylene (ET). We assessed ET production and the expression of related genes in the Azospirillum-strawberry plant interaction. Ethylene production was evaluated by gas chromatography in plants inoculated or not with A. brasilense REC3. Also, plants were treated with AgNO3 , an inhibitor of ET biosynthesis; with 1-aminocyclopropane-1-carboxylic acid (ACC), a precursor of ET biosynthesis; and with indole acetic acid (IAA). Plant dry biomass and the growth index were determined to assess the growth-promoting effect of A. brasilense REC3 in strawberry plants. Quantitative real time PCR (qRT-PCR) was performed to analyse relative expression of the genes Faetr1, Faers1 and Faein4, which encode ET receptors; Factr1 and Faein2, involved in the ET signalling pathway; Faacs1 encoding ACC synthase; Faaco1 encoding ACC oxidase; and Faaux1 and Faami1 for IAA synthesis enzymes. Results showed that ET acts as a rapid and transient signal in the first 12 h post-treatment. A. brasilense REC3-inoculated plants had a significantly higher growth index compared to control plants. Modulation of the genes Faetr1, Faers1, Faein4, Factr1, Faein2 and Faaco1 indicated activation of ET synthesis and signalling pathways. The up-regulation of Faaux1 and Faami1 involved in IAA synthesis suggested that inoculation with A. brasilense REC3 induces production of this auxin, modulating ET signalling. Ethylene production and up-regulation of genes associated with ET signalling in strawberry plants inoculated with A. brasilense REC3 support the priming activation characteristic of ISR. This type of resistance and the activation of systemic acquired resistance previously observed in this interaction indicate that both are present in strawberry plants, could act synergistically and increase protection against pathogens.


Assuntos
Azospirillum brasilense/metabolismo , Etilenos/metabolismo , Fragaria/microbiologia , Aminoácidos Cíclicos/farmacologia , Biomassa , Etilenos/antagonistas & inibidores , Fragaria/crescimento & desenvolvimento , Fragaria/metabolismo , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Ácidos Indolacéticos/farmacologia , Proteínas de Plantas/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Receptores de Superfície Celular/metabolismo , Nitrato de Prata/farmacologia
3.
Curr Microbiol ; 73(3): 346-353, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27246499

RESUMO

Tomato is one of the most economically attractive vegetable crops due to its high yields. Diseases cause significant losses in tomato production worldwide. We carried out Polymerase Chain Reaction studies to detect the presence of genes encoding antifungal compounds in the DNA of Pseudomonas putida strain PCI2. We also used liquid chromatography-electrospray tandem mass spectrometry to detect and quantify the production of compounds that increase the resistance of plants to diseases from culture supernatants of PCI2. In addition, we investigated the presence of 1-aminocyclopropane-1-carboxylic acid (ACC) deaminase in PCI2. Finally, PCI2 was used for inoculation of tomato seeds to study its potential biocontrol activity against Fusarium oxysporum MR193. The obtained results showed that no fragments for the encoding genes of hydrogen cyanide, pyoluteorin, 2,4-diacetylphloroglucinol, pyrrolnitrin, or phenazine-1-carboxylic acid were amplified from the DNA of PCI2. On the other hand, PCI2 produced salicylic acid and jasmonic acid in Luria-Bertani medium and grew in a culture medium containing ACC as the sole nitrogen source. We observed a reduction in disease incidence from 53.33 % in the pathogen control to 30 % in tomato plants pre-inoculated with PCI2 as well as increases in shoot and root dry weights in inoculated plants, as compared to the pathogenicity control. This study suggests that inoculation of tomato seeds with P. putida PCI2 increases the resistance of plants to root rot caused by F. oxysporum and that PCI2 produces compounds that may be involved at different levels in increasing such resistance. Thus, PCI2 could represent a non-contaminating management strategy potentially applicable in vegetable crops such as tomato.


Assuntos
Fusarium/fisiologia , Doenças das Plantas/imunologia , Pseudomonas putida/fisiologia , Solanum lycopersicum/microbiologia , Aminoácidos Cíclicos/imunologia , Resistência à Doença , Solanum lycopersicum/imunologia , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controle , Pseudomonas putida/genética
4.
Braz J Microbiol ; 46(1): 97-102, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26221093

RESUMO

Salinity is the leading abiotic stress hampering maize ( Zea mays L.) growth throughout the world, especially in Pakistan. During salinity stress, the endogenous ethylene level in plants increases, which retards proper root growth and consequent shoot growth of the plants. However, certain bacteria contain the enzyme 1-aminocyclopropane-1-carboxylate (ACC) deaminase, which converts 1-aminocyclopropane-1-carboxylic acid (an immediate precursor of ethylene biosynthesis in higher plants) into ammonia and α-ketobutyrate instead of ethylene. In the present study, two Pseudomonas bacterial strains containing ACC-deaminase were tested separately and in combinations with mineral fertilizers to determine their potential to minimize/undo the effects of salinity on maize plants grown under saline-sodic field conditions. The data recorded at 30, 50 and 70 days after sowing revealed that both the Pseudomonas bacterial strains improved root and shoot length, root and shoot fresh weight, and root and shoot dry weight up to 34, 43, 35, 71, 55 and 68%, respectively, when applied without chemical fertilizers: these parameter were enhanced up to 108, 95, 100, 131, 100 and 198%, respectively, when the strains were applied along with chemical fertilizers. It can be concluded that ACC-deaminase Pseudomonas bacterial strains applied alone and in conjunction with mineral fertilizers improved the root and shoot growth of maize seedlings grown in saline-sodic soil.


Assuntos
Desenvolvimento Vegetal , Raízes de Plantas/fisiologia , Brotos de Planta/fisiologia , Pseudomonas/crescimento & desenvolvimento , Microbiologia do Solo , Solo/química , Zea mays/fisiologia , Aminoácidos Cíclicos/metabolismo , Amônia/metabolismo , Butiratos , Carbono-Carbono Liases/metabolismo , Fertilizantes , Paquistão , Pseudomonas/enzimologia , Salinidade
5.
Braz. j. microbiol ; 46(1): 97-102, 05/2015. tab
Artigo em Inglês | LILACS | ID: lil-748258

RESUMO

Salinity is the leading abiotic stress hampering maize (Zea mays L.) growth throughout the world, especially in Pakistan. During salinity stress, the endogenous ethylene level in plants increases, which retards proper root growth and consequent shoot growth of the plants. However, certain bacteria contain the enzyme 1-aminocyclopropane-1-carboxylate (ACC) deaminase, which converts 1-aminocyclopropane-1-carboxylic acid (an immediate precursor of ethylene biosynthesis in higher plants) into ammonia and α-ketobutyrate instead of ethylene. In the present study, two Pseudomonas bacterial strains containing ACC-deaminase were tested separately and in combinations with mineral fertilizers to determine their potential to minimize/undo the effects of salinity on maize plants grown under saline-sodic field conditions. The data recorded at 30, 50 and 70 days after sowing revealed that both the Pseudomonas bacterial strains improved root and shoot length, root and shoot fresh weight, and root and shoot dry weight up to 34, 43, 35, 71, 55 and 68%, respectively, when applied without chemical fertilizers: these parameter were enhanced up to 108, 95, 100, 131, 100 and 198%, respectively, when the strains were applied along with chemical fertilizers. It can be concluded that ACC-deaminase Pseudomonas bacterial strains applied alone and in conjunction with mineral fertilizers improved the root and shoot growth of maize seedlings grown in saline-sodic soil.


Assuntos
Desenvolvimento Vegetal , Raízes de Plantas/fisiologia , Brotos de Planta/fisiologia , Pseudomonas/crescimento & desenvolvimento , Microbiologia do Solo , Solo/química , Zea mays/fisiologia , Aminoácidos Cíclicos/metabolismo , Amônia/metabolismo , Butiratos , Carbono-Carbono Liases/metabolismo , Fertilizantes , Paquistão , Pseudomonas/enzimologia , Salinidade
6.
Braz. J. Microbiol. ; 46(1): 97-102, Jan.- Mar. 2015. tab
Artigo em Inglês | VETINDEX | ID: vti-481349

RESUMO

Salinity is the leading abiotic stress hampering maize (Zea mays L.) growth throughout the world, especially in Pakistan. During salinity stress, the endogenous ethylene level in plants increases, which retards proper root growth and consequent shoot growth of the plants. However, certain bacteria contain the enzyme 1-aminocyclopropane-1-carboxylate (ACC) deaminase, which converts 1-aminocyclopropane-1-carboxylic acid (an immediate precursor of ethylene biosynthesis in higher plants) into ammonia and α-ketobutyrate instead of ethylene. In the present study, two Pseudomonas bacterial strains containing ACC-deaminase were tested separately and in combinations with mineral fertilizers to determine their potential to minimize/undo the effects of salinity on maize plants grown under saline-sodic field conditions. The data recorded at 30, 50 and 70 days after sowing revealed that both the Pseudomonas bacterial strains improved root and shoot length, root and shoot fresh weight, and root and shoot dry weight up to 34, 43, 35, 71, 55 and 68%, respectively, when applied without chemical fertilizers: these parameter were enhanced up to 108, 95, 100, 131, 100 and 198%, respectively, when the strains were applied along with chemical fertilizers. It can be concluded that ACC-deaminase Pseudomonas bacterial strains applied alone and in conjunction with mineral fertilizers improved the root and shoot growth of maize seedlings grown in saline-sodic soil.(AU)


Assuntos
Raízes de Plantas/fisiologia , Brotos de Planta/fisiologia , Pseudomonas/crescimento & desenvolvimento , Microbiologia do Solo , Solo/química , Zea mays/fisiologia , Aminoácidos Cíclicos/metabolismo , Amônia/metabolismo , Butiratos , Carbono-Carbono Liases/metabolismo , Fertilizantes , Paquistão , Pseudomonas/enzimologia , Salinidade
7.
Molecules ; 19(12): 19516-31, 2014 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-25432006

RESUMO

An enantioselective total synthesis of the natural amino acid (2S,4R,5R)-4,5-di-hydroxy-pipecolic acid starting from D-glucoheptono-1, 4-lactone is presented. The best sequence employed as a key step the intramolecular nucleophilic displacement by an amino function of a 6-O-p-toluene-sulphonyl derivative of a methyl D-arabino-hexonate and involved only 12 steps with an overall yield of 19%. The structures of the compounds synthesized were elucidated on the basis of comprehensive spectroscopic (NMR and MS) and computational analysis.


Assuntos
Aminoácidos Cíclicos/química , Aminoácidos Cíclicos/síntese química , Química Orgânica/métodos , Ácidos Pipecólicos/química , Azidas/química , Catálise , Modelos Moleculares , Piperidinas/síntese química , Piperidinas/química , Teoria Quântica , Termodinâmica
8.
J Plant Physiol ; 171(1): 14-22, 2014 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-24120532

RESUMO

Stylosanthes, a genus of tropical forage legume, is known to exhibit good persistence in saline soils, yet mechanisms for regulation of seed germination under salt stress are poorly understood. This study was carried out to evaluate the mode of action of salt stress on seed germination of Stylosanthes. 1-Aminocyclopropane-1-carboxylic acid (ACC) increased ethylene biosynthesis and germination of NaCl-inhibited seeds in a dose-dependent manner. Contents of ACC and germination of Stylosanthes humilis seeds increased following transfer from NaCl solution to deionised water, but not after transfer to l-α-(2-aminoethoxyvinyl)-glycine (AVG) solution, an inhibitor of ethylene biosynthesis. Ethylene biosynthesis was much larger in NaCl-treated seeds of Stylosanthes guianensis than in seeds of S. humilis and Stylosanthes capitata, a fact which was reflected in higher germination rates. S. guianensis seedlings also displayed higher growth and survival rates than S. humilis and S. capitata under salt stress. Moreover, smaller ACC levels, as well as reduced ethylene biosynthesis of S. capitata seeds were accompanied by lower germination under salt stress. In addition, S. capitata seedlings treated with NaCl solutions exhibited relatively lower growth and survival rates in comparison with S. humilis and S. guianensis. Thus, different abilities to synthesize ethylene by S. guianensis, S. humilis and S. capitata seeds explain the differences in tolerance to salt stress of the three species.


Assuntos
Aminoácidos Cíclicos/farmacologia , Etilenos/metabolismo , Fabaceae/fisiologia , Aminoácidos Cíclicos/análise , Aminobutiratos/farmacologia , Etilenos/análise , Fabaceae/efeitos dos fármacos , Fabaceae/crescimento & desenvolvimento , Germinação/efeitos dos fármacos , Hipocótilo/efeitos dos fármacos , Hipocótilo/crescimento & desenvolvimento , Hipocótilo/fisiologia , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/fisiologia , Tolerância ao Sal , Plântula/efeitos dos fármacos , Plântula/crescimento & desenvolvimento , Plântula/fisiologia , Sementes/efeitos dos fármacos , Sementes/crescimento & desenvolvimento , Sementes/fisiologia , Cloreto de Sódio/análise , Cloreto de Sódio/farmacologia , Especificidade da Espécie
9.
Interciencia ; 31(12): 876-880, dic. 2006. tab
Artigo em Inglês | LILACS | ID: lil-453636

RESUMO

Se determinó la digestibilidad ileal aparente de aminoácidos en maíz, sorgo, pasta de soya, gluten de maíz, harina de pescado, harina de carne y hueso, y salvado de trigo en pollos de engorda, utilizando dióxido de titanio y óxido de cromo como marcadores inertes de la dieta. Doce pollos fueron alimentados en dos ocasiones con 30g de cada ingrediente, con uno de los dos marcadores dietéticos, mediante la técnica de alimentación forzada. Se llevaron a cabo análisis de varianza con los resultados para determinar efectos de ingredientes y de marcadores. Se encontraron diferencias significativas en la digestibilidad de aminoácidos entre ingredientes, cuyo rango fue de 0,53 para cisteína en la harina de carne y hueso, hasta 0,97 para tirosina en pasta de soya. En todos los ingredientes los coeficientes de digestibilidad de aminoácidos calculados con base en titanio fueron mayores (P<0,05) que aquellos determinados con base en cromo. La excepción fue para salvado de trigo donde no se encontró efecto significativo del marcador utilizado (P>0,05). Los coeficientes de digestibilidad de aminoácidos mostraron una menor variación cuando el dióxido de titanio fue usado como marcador dietético. Se concluye que el dióxido de titanio es más confiable que el cromo como marcador dietético, siendo menos variable y obteniéndose mayor digestibilidad, lo cual indica una mayor recuperación


Assuntos
Animais , Aminoácidos Cíclicos , Ração Animal , Galinhas , Dieta , Fenômenos Fisiológicos da Nutrição Animal , México
10.
Acta bioquím. clín. latinoam ; 36(4): 583-592, dic. 2002. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-330750

RESUMO

Se estudiaron 14 mujeres, de 22 a 35 años, premenopaúsicas, clínicamente sanas, residentes en Comodoro Rivadavia (Chubut), con valores normales de densidad mineral ósea de columna lumbar y cuello de fémur; los promedios ñ DE de peso e índice de masa corporal fueron, respectivamente: 57,7 ñ 3,8 (kg); 21,8 ñ 1,7 kg/m². La ingesta de calcio (ICa) se calculó en base a una encuesta alimentaria. En orina basal (A), con sobrecarga de agua (B) y de 24 h (C), se determinaron: calcio (Ca), deoxipiridinolina (D-Pir) y creatinina (crea), calculando las relaciones Ca/crea y D-Pir/crea. Los resultados promedio ñ DE fueron: ICa (mg/día): 720 ñ 284; Ca/crea (mg/mg): A: 0,065 ñ 0,039; B: 0,050 ñ 0,022; C: 0,089 ñ 0,027; D-Pir/crea (nM/mM) A: 5,9 ñ 2,2; B: 5,5 ñ 2,0; C: 5,1 ñ 1,4. Ca/crea en A y B no fueron significativamente menores que C (p 0,025); Ca/crea en C correlacionó con ICa (p = 0,002). D-Pir/crea en A, B y C no fueron diferentes. Estos resultados sugieren que: 1) las muestras A y B podrían utilizarse indistintinamente para determinar las relaciones urinarias Ca/crea y D-Pir/crea; 2) Ca/crea en C muestra una elevada correlación con ICa; 3) los valores normales de densidad de masa ósea (DMO) y D-Pir/crea en éstas mujeres premenopaúsicas, indican una adaptación al amplio rango de ICa


Assuntos
Humanos , Adulto , Feminino , Aminoácidos Cíclicos/urina , Cálcio , Creatinina , Reabsorção Óssea/diagnóstico , Aminoácidos Cíclicos , Cálcio , Creatinina , Biomarcadores/urina
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