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1.
Rev. Ciênc. Agrovet. (Online) ; 21(3): 344-348, 2022. tab, graf
Artigo em Inglês | VETINDEX | ID: biblio-1411215

Resumo

The present study aimed to evaluate the effect of applying different concentrations of niacin, at different times in relation to nitrogen fertilization, on the characteristics of Urochloa brizantha. The treatments consisted of applying three concentrations of niacin (0, 100, and 200 mg L-1) and three different moments (two days before, together, and two days after nitrogen fertilization). It was found that there was variation in response, mainly concerning the moment of application of the vitamins, in which the joint and subsequent application of fertilization generally exceeded the application performed previously, and of both concentrations used (100 and 200 mg L-1), in relation to the control without vitamin application. In this way, the application of niacin at a concentration of 100 mg L-1, carried out jointly or after nitrogen fertilization, provides better conditions for developing and producing dry matter of Urochloa brizantha due to the presence of nitrogen.


O presente estudo teve como objetivo avaliar o efeito da aplicação de diferentes concentrações de niacina, em momentos distintos em relação à adubação nitrogenada, sobre as características de Urochloa brizantha. Os tratamentos foram compostos pela aplicação de três concentrações de niacina (0, 100 e 200 mg L-1) e três momentos distintos (dois dias antes, juntamente e dois dias após a adubação nitrogenada). Verificou-se que houve variação de resposta, principalmente em relação ao momento de aplicação das vitaminas, em que as aplicações conjunta e posterior à adubação superaram, de maneira geral, a aplicação realizada anteriormente, e de ambas as concentrações utilizadas (100 e 200 mg L-1), em relação ao controle sem vitamina. Desta maneira, a aplicação de niacina em concentração de 100 mg L-1, realizada de maneira conjunta ou posterior à adubação nitrogenada, propicia melhores condições para o desenvolvimento e a produção de matéria seca de Urochloa brizantha, devido à presença do nitrogênio.


Assuntos
Poaceae/química , Niacina/administração & dosagem , Nitrogênio/administração & dosagem , Niacinamida/administração & dosagem , Fertilizantes
2.
Acta sci., Biol. sci ; 42: e54187, fev. 2020. graf, ilus, tab
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1460947

Resumo

Amburana cearensisis an arboreal legume of the Fabaceaefamily,with high phytotherapic and medicinal potential due the presence of secondary metabolites. The objective of this study was to evaluate the effect of 2,4-dichlorophenoxyacetic acid (2,4-D) and 4-amino-2,5,6-trichloro-2-pyridinecarboxylic acid (picloram) on the in vitroinduction of callogenesis of A. cearensisand analyze the biochemical and phytochemical potential of these calluses. For callus induction, leaf and cotyledon segments were used as explants, which were inoculated in woody plant medium (WPM) supplemented with different concentrations of 2,4-D (0, 5, 10, 20, 40 μM) or picloram (0, 5, 10, 20, 40, 80 μM). The callus growth curve was estimated based on fresh weight, measured at 7-day intervals until 28 days after inoculation. The calluses were analyzed by biochemical tests to quantify the reducing sugars and total proteins. Phytochemical screening and high-performance liquid chromatography were performed to establish the phytochemical profile of extracts from calluses. The concentrations of 21.94 μMand 26.46 μMof 2,4-Dinduced the greatest formation of compact and friable calluses from the leaf and cotyledon segments, respectively. The growth curve had two distinct phases(lag and exponential) for both types of calluses evaluated. The maximum levels of reducing sugars and total proteins in the calluses from leaf and cotyledon segments were obtained on the day of inoculation and after 28 days of cultivation, respectively. The results of the phytochemical analysis identified the presence of coumarin in all the extracts evaluated, this secondary metabolite has high pharmacological potential.


Assuntos
Compostos Fitoquímicos , Fabaceae/genética , Fabaceae/química , Fenômenos Bioquímicos , Plantas Medicinais
3.
Braz. J. Biol. ; 78(4): 686-690, Nov. 2018. tab
Artigo em Inglês | VETINDEX | ID: vti-736207

Resumo

Kiwifruit are a popular fruit worldwide; however, plant growth is threatened by abiotic stresses such as drought and high temperatures. Niacin treatment in plants has been shown to increase NADPH levels, thus enhancing abiotic stresses tolerance. Here, we evaluate the effect of niacin solution spray treatment on NADPH levels in the kiwifruit cultivars Hayward and Xuxiang. We found that spray treatment with niacin solution promoted NADPH and NADP+ levels and decreased both O2·- production and H2O2 contents in leaves during a short period. In fruit, NADPH contents increased during early development, but decreased later. However, no effect on NADP+ levels has been observed throughout fruit development. In summary, this report suggests that niacin may be used to increase NADPH oxidases, thus increasing stress-tolerance in kiwifruit during encounter of short-term stressful conditions.(AU)


Kiwis são uma fruta popular em todo o mundo; No entanto, o crescimento das plantas é ameaçado por estresses abióticos como a seca e as altas temperaturas. O tratamento com niacina em plantas mostrou aumentar os níveis de NADPH, aumentando assim a tolerância a stress abiótico. Aqui, avaliamos o efeito do tratamento com spray de solução de niacina sobre os níveis de NADPH nos cultivares de kiwis Hayward e Xuxiang. Descobrimos que o tratamento por spray com solução de niacina promoveu níveis de NADPH e NADP + e diminuiu a produção de O2·- e os teores de H2O2 nas folhas durante um curto período. Nos frutos, os teores de NADPH aumentaram durante o desenvolvimento precoce, mas diminuíram mais tarde. No entanto, não se observou qualquer efeito nos níveis de NADP + ao longo do desenvolvimento do fruto. Em resumo, este relatório sugere que a niacina pode ser utilizada para aumentar NADPH oxidases, aumentando assim a tolerância ao estresse em kiwis durante o encontro de condições estressantes de curto prazo.(AU)


Assuntos
Actinidia/crescimento & desenvolvimento , Niacina/farmacologia , Estresse Fisiológico , NADPH Oxidases
4.
R. Ci. agrovet. ; 17(1): 83-90, 2018. graf, tab
Artigo em Português | VETINDEX | ID: vti-734015

Resumo

A cultura do feijoeiro é de grande importância socioeconômica em todas as regiões brasileiras. Seu cultivo, entretanto, ainda está relacionado a técnicas rudimentares que prejudicam a produtividade. O emprego de vitaminas contribui para a melhora do desenvolvimento vegetativo e reprodutivo, incrementando as condições fisiológicas das plantas. Assim, o estudo objetivou avaliar os efeitos da aplicação de niacina ou tiamina sobre as características de desenvolvimento vegetativo e produtivo do feijoeiro a partir do tratamento de sementes, conduzido em vasos. Dois experimentos foram conduzidos e, em ambos, os tratamentos foram definidos pela aplicação de Niacina ou Tiamina em cinco diferentes dosagens (0,00; 5,00; 10,00; 15,00 e 20,00 mg kg-¹), juntamente com fungicida. Foram avaliadas variáveis ligadas à emergência das plântulas, ao desenvolvimento vegetativo e à produtividade de grãos. Verificou-se que, para o feijoeiro (cv. BRS Estilo), o pré-tratamento de sementes com niacina diminuiu o tempo de emergência das plântulas (20,31%) e estimulou o desenvolvimento dos trifólios (16,21%). A aplicação da tiamina, por sua vez, aumentou a emergência das plântulas na primeira contagem (287,52%), estimulou a taxa de emergência (36,72%) e o índice de velocidade de emergência (65,76%), diminuiu o tempo médio de emergência (19,03) e proporcionou incremento do número de vagens por planta (116,28%), de grãos por planta (122,28%) e da produtividade de grãos (127,50%), quando comparados ao tratamento controle.(AU)


Bean crop has socioeconomic importance in all Brazilian regions, but its cultivation is still related to rudimentary techniques that affect productivity. The use of vitamins contributes to the improvement of the vegetative and reproductive development, improving the plants physiological conditions. The objective of this study was to evaluate the effects of the application of niacin or thiamine on the vegetative and productive development characteristics of bean, in pots. Two experiments were conducted, on both the treatments were defined by the application of Niacin or Thiamin in five different dosages (0.00, 5.00, 10.00,15.00 and 20.00 mg kg-¹) along with fungicide in seed treatment. Variables related to seedling emergence,vegetative development and grain production were evaluated. It was verified, for bean plants (cv. BRSEstilo), that seed pre-treatment with niacin decreases seedling emergence time (20.31%) and stimulated the development of trefoils (16.21%), while the application of thiamine increased seedling emergence at the first count (287.52%), stimulated the emergence rate (36.72%) and the emergence speed index (65.76%), decreased the mean time of emergence (19.03) and increased the number of pods per plant (116.28%), grains per plant (122.28%) and grain productivity (127.50%), compared to the control treatment.(AU)


Assuntos
Niacina/fisiologia , Phaseolus/crescimento & desenvolvimento , Niacinamida , Tiamina , Desenvolvimento Vegetal , Grão Comestível/crescimento & desenvolvimento , 24444
5.
Rev. Ciênc. Agrovet. (Online) ; 17(1): 83-90, 2018. graf, tab
Artigo em Português | VETINDEX | ID: biblio-1488209

Resumo

A cultura do feijoeiro é de grande importância socioeconômica em todas as regiões brasileiras. Seu cultivo, entretanto, ainda está relacionado a técnicas rudimentares que prejudicam a produtividade. O emprego de vitaminas contribui para a melhora do desenvolvimento vegetativo e reprodutivo, incrementando as condições fisiológicas das plantas. Assim, o estudo objetivou avaliar os efeitos da aplicação de niacina ou tiamina sobre as características de desenvolvimento vegetativo e produtivo do feijoeiro a partir do tratamento de sementes, conduzido em vasos. Dois experimentos foram conduzidos e, em ambos, os tratamentos foram definidos pela aplicação de Niacina ou Tiamina em cinco diferentes dosagens (0,00; 5,00; 10,00; 15,00 e 20,00 mg kg-¹), juntamente com fungicida. Foram avaliadas variáveis ligadas à emergência das plântulas, ao desenvolvimento vegetativo e à produtividade de grãos. Verificou-se que, para o feijoeiro (cv. BRS Estilo), o pré-tratamento de sementes com niacina diminuiu o tempo de emergência das plântulas (20,31%) e estimulou o desenvolvimento dos trifólios (16,21%). A aplicação da tiamina, por sua vez, aumentou a emergência das plântulas na primeira contagem (287,52%), estimulou a taxa de emergência (36,72%) e o índice de velocidade de emergência (65,76%), diminuiu o tempo médio de emergência (19,03) e proporcionou incremento do número de vagens por planta (116,28%), de grãos por planta (122,28%) e da produtividade de grãos (127,50%), quando comparados ao tratamento controle.


Bean crop has socioeconomic importance in all Brazilian regions, but its cultivation is still related to rudimentary techniques that affect productivity. The use of vitamins contributes to the improvement of the vegetative and reproductive development, improving the plants physiological conditions. The objective of this study was to evaluate the effects of the application of niacin or thiamine on the vegetative and productive development characteristics of bean, in pots. Two experiments were conducted, on both the treatments were defined by the application of Niacin or Thiamin in five different dosages (0.00, 5.00, 10.00,15.00 and 20.00 mg kg-¹) along with fungicide in seed treatment. Variables related to seedling emergence,vegetative development and grain production were evaluated. It was verified, for bean plants (cv. BRSEstilo), that seed pre-treatment with niacin decreases seedling emergence time (20.31%) and stimulated the development of trefoils (16.21%), while the application of thiamine increased seedling emergence at the first count (287.52%), stimulated the emergence rate (36.72%) and the emergence speed index (65.76%), decreased the mean time of emergence (19.03) and increased the number of pods per plant (116.28%), grains per plant (122.28%) and grain productivity (127.50%), compared to the control treatment.


Assuntos
Desenvolvimento Vegetal , Niacina/fisiologia , Niacinamida , Phaseolus/crescimento & desenvolvimento , Tiamina , 24444 , Grão Comestível/crescimento & desenvolvimento
6.
Acta sci., Biol. sci ; 33(4): 437-443, Out.-Dec. 2011.
Artigo em Português | LILACS-Express | LILACS, VETINDEX | ID: biblio-1460688

Resumo

The effect of 2-pyridinecarboxylic acid (picolinic acid) on trypanosomes of the subgenus Schizotrypanum isolated from the bat Phyllostomus hastatus was determined in this study. Picolinic acid, at 50 µg mL-1, inhibited epimastigote growth by 99% after 12 days incubation. In addition, trypomastigote motility decreased by 50% after 6h and completely after 24h in the presence of 50 µg mL-1 picolinic acid. The 50% cytotoxic concentration on HEp-2 cell line was 275 µg mL-1 after 4 days incubation. Altogether, these results indicate higher toxicity against trypanosomes. The inhibitory effect of picolinic acid on epimastigote growth can be partially reversed by nicotinic acid and L-tryptophan, suggesting a competitive inhibition. Furthermore, two anti-Trypanosoma (Schizotrypanum) cruzi drugs were also evaluated with regard to bat trypanosome growth. Benznidazole, at 50 µg mL-1, inhibited epimastigote growth by 90% after 12 days incubation. Nifurtimox, at the same concentration, caused 96% growth inhibition after four days incubation. Corroborating a previous study, bat trypanosomes are a good model for screening new trypanocidal compounds. Moreover, they can be used to study many biological processes common to human pathogenic trypanosomatids.


The effect of 2-pyridinecarboxylic acid (picolinic acid) on trypanosomes of the subgenus Schizotrypanum isolated from the bat Phyllostomus hastatus was determined in this study. Picolinic acid, at 50 µg mL-1, inhibited epimastigote growth by 99% after 12 days incubation. In addition, trypomastigote motility decreased by 50% after 6h and completely after 24h in the presence of 50 µg mL-1 picolinic acid. The 50% cytotoxic concentration on HEp-2 cell line was 275 µg mL-1 after 4 days incubation. Altogether, these results indicate higher toxicity against trypanosomes. The inhibitory effect of picolinic acid on epimastigote growth can be partially reversed by nicotinic acid and L-tryptophan, suggesting a competitive inhibition. Furthermore, two anti-Trypanosoma (Schizotrypanum) cruzi drugs were also evaluated with regard to bat trypanosome growth. Benznidazole, at 50 µg mL-1, inhibited epimastigote growth by 90% after 12 days incubation. Nifurtimox, at the same concentration, caused 96% growth inhibition after four days incubation. Corroborating a previous study, bat trypanosomes are a good model for screening new trypanocidal compounds. Moreover, they can be used to study many biological processes common to human pathogenic trypanosomatids.

7.
Acta sci., Biol. sci ; 33(4): 437-443, Out.-Dec. 2011. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-868149

Resumo

The effect of 2-pyridinecarboxylic acid (picolinic acid) on trypanosomes of the subgenus Schizotrypanum isolated from the bat Phyllostomus hastatus was determined in this study. Picolinic acid, at 50 µg mL-1, inhibited epimastigote growth by 99% after 12 days incubation. In addition, trypomastigote motility decreased by 50% after 6h and completely after 24h in the presence of 50 µg mL-1 picolinic acid. The 50% cytotoxic concentration on HEp-2 cell line was 275 µg mL-1 after 4 days incubation. Altogether, these results indicate higher toxicity against trypanosomes. The inhibitory effect of picolinic acid on epimastigote growth can be partially reversed by nicotinic acid and L-tryptophan, suggesting a competitive inhibition. Furthermore, two anti-Trypanosoma (Schizotrypanum) cruzi drugs were also evaluated with regard to bat trypanosome growth. Benznidazole, at 50 µg mL-1, inhibited epimastigote growth by 90% after 12 days incubation. Nifurtimox, at the same concentration, caused 96% growth inhibition after four days incubation. Corroborating a previous study, bat trypanosomes are a good model for screening new trypanocidal compounds. Moreover, they can be used to study many biological processes common to human pathogenic trypanosomatids.


O efeito do ácido 2-piridinocarboxílico (ácido picolínico) sobre um tripanossoma do subgênero Schizotrypanum isolado do morcego Phyllostomus hastatus foi determinado neste estudo. O ácido picolínico, na concentração de 50 µg mL-1, inibiu 99% do crescimento de epimastigotas após 12 dias de incubação. Além disso, houve um decréscimo de 50 e 100% na mobilidade dos tripomastigotas após 6 e 24h, respectivamente, em presença de ácido picolínico na concentração de 50 µg mL-1. A concentração citotóxica 50% para células HEp-2 foi de 275 µg mL-1 após quatro dias de incubação. Esses resultados indicam maior toxicidade contra os tripanossomas. O efeito inibitório do ácido picolínico sobre o crescimento de epimastigotas pode ser parcialmente revertido por ácido nicotínico e L-triptofano, sugerindo inibição competitiva. Adicionalmente, o efeito de dois fármacos com atividade anti-Trypanosoma (Schizotrypanum) cruzi foi avaliado sobre o crescimento do tripanossoma de morcego. Benzonidazol, na concentração de 50 µg mL-1, inibiu 90% do crescimento de epimastigotas após 12 dias de incubação. Nifurtimox, na mesma concentração, causou 96% de inibição do crescimento após quatro dias de incubação. Corroborando trabalhos anteriores, tripanossomas de morcegos são bons modelos para seleção inicial de novos compostos tripanocidas. Além disso, eles podem ser utilizados para estudar vários processos biológicos comuns aos tripanossomatídeos patogênicos ao homem.


Assuntos
Animais , Tripanossomíase , Quirópteros , Anti-Infecciosos
8.
Acta Sci. Biol. Sci. ; 33(4): 437-443, 2011.
Artigo em Português | VETINDEX | ID: vti-726046

Resumo

The effect of 2-pyridinecarboxylic acid (picolinic acid) on trypanosomes of the subgenus Schizotrypanum isolated from the bat Phyllostomus hastatus was determined in this study. Picolinic acid, at 50 µg mL-1, inhibited epimastigote growth by 99% after 12 days incubation. In addition, trypomastigote motility decreased by 50% after 6h and completely after 24h in the presence of 50 µg mL-1 picolinic acid. The 50% cytotoxic concentration on HEp-2 cell line was 275 µg mL-1 after 4 days incubation. Altogether, these results indicate higher toxicity against trypanosomes. The inhibitory effect of picolinic acid on epimastigote growth can be partially reversed by nicotinic acid and L-tryptophan, suggesting a competitive inhibition. Furthermore, two anti-Trypanosoma (Schizotrypanum) cruzi drugs were also evaluated with regard to bat trypanosome growth. Benznidazole, at 50 µg mL-1, inhibited epimastigote growth by 90% after 12 days incubation. Nifurtimox, at the same concentration, caused 96% growth inhibition after four days incubation. Corroborating a previous study, bat trypanosomes are a good model for screening new trypanocidal compounds. Moreover, they can be used to study many biological processes common to human pathogenic trypanosomatids.


The effect of 2-pyridinecarboxylic acid (picolinic acid) on trypanosomes of the subgenus Schizotrypanum isolated from the bat Phyllostomus hastatus was determined in this study. Picolinic acid, at 50 µg mL-1, inhibited epimastigote growth by 99% after 12 days incubation. In addition, trypomastigote motility decreased by 50% after 6h and completely after 24h in the presence of 50 µg mL-1 picolinic acid. The 50% cytotoxic concentration on HEp-2 cell line was 275 µg mL-1 after 4 days incubation. Altogether, these results indicate higher toxicity against trypanosomes. The inhibitory effect of picolinic acid on epimastigote growth can be partially reversed by nicotinic acid and L-tryptophan, suggesting a competitive inhibition. Furthermore, two anti-Trypanosoma (Schizotrypanum) cruzi drugs were also evaluated with regard to bat trypanosome growth. Benznidazole, at 50 µg mL-1, inhibited epimastigote growth by 90% after 12 days incubation. Nifurtimox, at the same concentration, caused 96% growth inhibition after four days incubation. Corroborating a previous study, bat trypanosomes are a good model for screening new trypanocidal compounds. Moreover, they can be used to study many biological processes common to human pathogenic trypanosomatids.

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