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1.
Braz. J. Pharm. Sci. (Online) ; 58: e20160, 2022. tab, graf
Article in English | LILACS | ID: biblio-1403723

ABSTRACT

Abstract Pharmacokinetic studies were carried out in male and female rats to quantify silymarin as silybin (A+B) after the oral administration of various silymarin formulations combined with three bioenhancers, namely, lysergol, piperine, and fulvic acid, and compared with plain silymarin formulation (control). A non-compartmental analysis, model independent analysis, was utilized, and various pharmacokinetic parameters (C max, T max, and AUC 0-t) were calculated individually for each treatment group, and the values were expressed as mean ± SEM (n = 6). Plasma samples obtained from the rats were analyzed for the concentration of silymarin through a validated RP-HPLC method and on the basis of data generated from the pharmacokinetic studies. Results indicated that the bioenhancers augmented pharmacokinetic parameters and bioavailability increased 2.4-14.5-fold in all the formulations compared with the control. The current work envisages the development of an industrially viable product that can be further subjected to clinical trials and scientifically supports the development of silymarin as a contemporary therapeutic agent with enhanced bioavailability and medicinal values.


Subject(s)
Animals , Male , Female , Rats , Silymarin/analysis , Silymarin/agonists , Acids/adverse effects , Biological Availability , Administration, Oral , Chromatography, High Pressure Liquid/methods
2.
Front Microbiol ; 12: 719653, 2021.
Article in English | MEDLINE | ID: mdl-34777275

ABSTRACT

Plant growth-promoting bacteria (PGPB) and humic substances (HSs) are promising options for reducing the use of pesticides and mineral fertilizers. Although many studies have shown the effects of PGPB and HSs separately, little information is available on plant responses to the combined application of these biostimulants despite the great potential for the simultaneous action of these biological inputs. Thus, the objective of this review is to present an overview of scientific studies that addressed the application of PGPB and HSs to different crops. First, we discuss the effect of these biostimulants on biological nitrogen fixation, the various effects of the inoculation of beneficial bacteria combined with the application of HSs on promoting the growth of nonleguminous plants and how this combination can increase bacterial colonization of plant hosts. We also address the effect of PGPB and HSs on plant responses to abiotic stresses, in addition to discussing the role of HSs in protecting plants against pathogens. There is a lack of studies that address the role of PGPB + HSs in biocontrol. Understanding the factors involved in the promotion of plant growth through the application of PGPB and HSs can assist in the development of efficient biostimulants for agricultural management. This approach has the potential to accelerate the transition from conventional cultivation to sustainable agrosystems.

3.
Mar Pollut Bull ; 146: 703-710, 2019 Sep.
Article in English | MEDLINE | ID: mdl-31426212

ABSTRACT

18 polycyclic aromatic hydrocarbons (PAHs) were evaluated in the Jaguaribe River to explore the influence of grain size, organic carbon, humic and fulvic acids and black carbon on their adsorption onto sediment. The ∑PAHs concentrations variated from 0.6 to 3752.0 ng g-1 with highest concentrations in the estuarine zone. The PAHs predominant source along the river was from mixed sources, mainly related to biomass combustion, small oil spills related to recreational nautical activities and runoff from cities. Organic and inorganic parameters presented influence on PAHs distribution along the river, with humic acid as a determinant factor. These research findings are of importance to an assessment of the fate and transport of PAHs in estuarine systems.


Subject(s)
Geologic Sediments/chemistry , Polycyclic Aromatic Hydrocarbons/analysis , Water Pollutants, Chemical/analysis , Brazil , Cities , Environmental Monitoring , Geologic Sediments/analysis , Humic Substances/analysis , Rivers/chemistry , Tropical Climate , Wetlands
4.
Biosci. j. (Online) ; 35(3): 732-740, may./jun. 2019. tab, graf
Article in English | LILACS | ID: biblio-1048631

ABSTRACT

Soil organic matter has a strong relation to total organic carbon, and about 85% of organic carbon consists of humic substances (HS), classified as humin (HU), humic (HA) and fulvic acids (FA), and denominated as recalcitrant carbon in soil. HS are formed by complex, heterogeneous and polydisperse molecules, which have significant influence on the soil physical and chemical characteristics. The study evaluates the hypothesis that agricultural soils treated with organic residues may present higher carbon stocks as presented in forest soils. The aim of this study was to evaluate alterations in recalcitrant carbon and nitrogen stocks in Oxisol (Forest - FL, unfertilized Brachiaria - UB, and fertilized Brachiaria - FB) and Cambisol (Forest - FC, Coastcross - CC, sugarcane - CA, and silage corn - SM) at surface (0.0 - 0.1) and subsurface (0.1 - 0.2 m), in the Zona da Mata in Minas Gerais state, Brazil. Result shows that fertilization, low soil disturbance and residual removal promoted increase of C and N content in HS, being close to native forests. Both, carbon and nitrogen recalcitrant, presented reduction with soil depth. HU ranged from 10.5 to 16.7 g kg-1 and presented the highest concentration compared to FA and HA. In Oxisol, FL and FB presented the highest SH concentration and demonstrate the positive effect of fertilization on carbon stocks improving soil quality in well-managed and productive areas. While, In Cambisol, FC and CC presented higher carbon and nitrogen in HS, mainly for HU and HA fractions, and SM showed the lowest concentrations in all fractions. Our results suggest that soil managements with lower soil disturbance and residual removal promotes increasing of carbon and nitrogen in recalcitrant fraction, with concentration close to native forests. Pasture should be fertilized to improve recalcitrant carbon and nitrogen stocks, avoiding process of degradation in tropical soil. It is an important outcome due to high levels of degraded areas in Brazil caused by inadequate use of soil mainly with pasture.


A matéria orgânica do solo tem uma forte relação com o carbono orgânico total, cerca de 85% do carbono orgânico é composto por substâncias húmicas (HS), classificadas como humina (HU), ácidos húmicos (HA) e fúlvicos (FA), denominadas como carbono recalcitrante no solo. As HS são formadas por moléculas complexas, heterogêneas e polidispersas, que exercem influência significativa nas características físicas e químicas do solo. O estudo avalia a hipótese de que solos agrícolas tratados com resíduos orgânicos podem apresentar maiores estoques de carbono como os encontrados em solos florestais. O objetivo destetrabalho foi avaliar as alterações nos estoques de carbono e nitrogênio recalcitrantes em Latossolo (Floresta - FL, Brachiaria não fertilizada ­ UB, e Brachiaria fertilizada - FB) e Cambissolo (Floresta - FC, coastcross - CC, cana-de-açúcar e milho para silagem - SM) na superfície (0,0 - 0,1) e sub-superfície (0,1 - 0,2 m), na Zona da Mata em Minas Gerais, Brasil. Os resultados mostram que a adubação, a baixa perturbação do solo e a remoção dos resíduos promoveram aumento do teor de C e N na HS, estando próximos às florestas nativas. Ambos, carbono e nitrogênio recalcitrantes, apresentaram redução com a profundidade do solo. A HU variou de 10,5 a 16,7 g kg-1 e apresentou a maior concentração em relação à FA e HA. Em Latossolo, FL e FB apresentaram a maior concentração de SH e demonstraram o efeito positivo da adubação nos estoques de carbono, melhorando a qualidade do solo em áreas bem manejadas e produtivas. Enquanto, no Cambissolo, FC e CC apresentarammaiores teores de carbono e nitrogênio nas HS, principalmente nas frações HU e HA, e SM apresentou as menores concentrações em todas as frações. Nossos resultados mostram que manejos de solo com menor perturbação e remoção de resíduos promovem o aumento de carbono e nitrogênio em frações recalcitrantes, com concentração próxima às florestas nativas. A pastagem deve ser fertilizada para melhorar o estoque de carbono e nitrogênio recalcitrante, evitando o processo de degradação do solo tropical. Este é um resultado importante devido aos altos níveis de áreas degradadas no Brasil causadas pelo uso inadequado do solo,principalmente com pastagens.


Subject(s)
Agricultural Zones , Brachiaria , Garbage , Carbon , Tropical Ecosystem , Nitrogen
5.
Biometals ; 29(2): 275-85, 2016 Apr.
Article in English | MEDLINE | ID: mdl-26857737

ABSTRACT

The use of theoretical calculation to determine structural properties of fulvate-metal complex (zinc, copper and iron) is here related. The species were proposed in the ratio 1:1 and 2:1 for which the molecular structure was obtained through the semi-empirical method PM6. The calculation of thermodynamic stability ([Formula: see text]) predicted that the iron complex were more exo-energetic. Metallic ions were coordinated to the phtalate groups of the model-structure of fulvic acid Suwannee River and the calculations of vibrational frequencies suggested that hydrogen bonds may help on the stability of the complex formation.


Subject(s)
Benzopyrans/chemistry , Coordination Complexes/chemistry , Copper/chemistry , Iron/chemistry , Zinc/chemistry , Hydrogen Bonding , Hydrogen-Ion Concentration , Models, Molecular , Molecular Conformation , Thermodynamics
6.
Acta Sci. Anim. Sci. ; 33(4): 395-401, 2011.
Article in Portuguese | VETINDEX | ID: vti-725095

ABSTRACT

The objective of this work was to evaluate the inclusion of humic substances in starter concentrate on the performance of dairy calves and rumen development. Twenty Holstein calves were used in a completely randomized block design and distributed in two treatments according to inclusion of humic substances in concentrate: 1) Control; 2) Humic substances. Animals received 4 L d-1 liquid diet and starter concentrate ad libitum. Fecal score analyses were carried out daily, and calves were weighed weekly and growth measurements and blood samples for glucose, urea-N and -hidroxibutyrate (BHBA) were taken. The calves were weaned at eight weeks of age and slaughtered for evaluation of forestomach development. There were no effects (p > 0.05) between treatments or treatment x age interaction for concentrate intake, weight gain, growth measurements or blood parameters. Fecal scores and rumen development were not affected (p > 0.05) by the inclusion of humic substances. There were no benefits from the inclusion of humic substances in starter concentrate on performance or rumen development of dairy calves


O objetivo deste estudo foi avaliar a inclusão de substâncias húmicas na dieta sobre o desempenho e o desenvolvimento ruminal de bezerros leiteiros da raça Holandesa. Foram utilizados 20 animais em delineamento experimental em blocos completos aleatorizados, distribuídos nos seguintes tratamentos: 1) controle; 2) substâncias húmicas, via concentrado inicial. Os animais receberam 4 L d-1 da dieta líquida e concentrado inicial ad libitum. Diariamente foram realizadas análise de escore fecal, e semanalmente foram realizadas pesagens, medidas de crescimento corporal e colheita de sangue para a determinação de glicose, N-ureico e -hidroxibutirato (BHBA). Os animais foram desaleitados na oitava semana de idade e foram abatidos para análise do desenvolvimento do trato digestório superior. Não houve efeito significativo (p > 0,05) entre os tratamentos ou interação tratamento x idade para os parâmetros consumo de concentrado, ganho de peso, medidas de crescimento corporal e parâmetros sanguíneos. Entretanto, foi observado efeito de idade (p 0,0001) para todos os parâmetros avaliados. O escore fecal e o desenvolvimento ruminal também não foram afetados pelos tratamentos (p > 0,05). Não houve efeito da inclusão de substâncias húmicas na dieta quanto ao desempenho e desenvolvimento ruminal de bezerros leiteiros.

7.
Acta sci., Anim. sci ; 33(4): 395-401, 2011.
Article in Portuguese | LILACS-Express | VETINDEX | ID: biblio-1459372

ABSTRACT

The objective of this work was to evaluate the inclusion of humic substances in starter concentrate on the performance of dairy calves and rumen development. Twenty Holstein calves were used in a completely randomized block design and distributed in two treatments according to inclusion of humic substances in concentrate: 1) Control; 2) Humic substances. Animals received 4 L d-1 liquid diet and starter concentrate ad libitum. Fecal score analyses were carried out daily, and calves were weighed weekly and growth measurements and blood samples for glucose, urea-N and -hidroxibutyrate (BHBA) were taken. The calves were weaned at eight weeks of age and slaughtered for evaluation of forestomach development. There were no effects (p > 0.05) between treatments or treatment x age interaction for concentrate intake, weight gain, growth measurements or blood parameters. Fecal scores and rumen development were not affected (p > 0.05) by the inclusion of humic substances. There were no benefits from the inclusion of humic substances in starter concentrate on performance or rumen development of dairy calves


O objetivo deste estudo foi avaliar a inclusão de substâncias húmicas na dieta sobre o desempenho e o desenvolvimento ruminal de bezerros leiteiros da raça Holandesa. Foram utilizados 20 animais em delineamento experimental em blocos completos aleatorizados, distribuídos nos seguintes tratamentos: 1) controle; 2) substâncias húmicas, via concentrado inicial. Os animais receberam 4 L d-1 da dieta líquida e concentrado inicial ad libitum. Diariamente foram realizadas análise de escore fecal, e semanalmente foram realizadas pesagens, medidas de crescimento corporal e colheita de sangue para a determinação de glicose, N-ureico e -hidroxibutirato (BHBA). Os animais foram desaleitados na oitava semana de idade e foram abatidos para análise do desenvolvimento do trato digestório superior. Não houve efeito significativo (p > 0,05) entre os tratamentos ou interação tratamento x idade para os parâmetros consumo de concentrado, ganho de peso, medidas de crescimento corporal e parâmetros sanguíneos. Entretanto, foi observado efeito de idade (p 0,0001) para todos os parâmetros avaliados. O escore fecal e o desenvolvimento ruminal também não foram afetados pelos tratamentos (p > 0,05). Não houve efeito da inclusão de substâncias húmicas na dieta quanto ao desempenho e desenvolvimento ruminal de bezerros leiteiros.

8.
Acta sci., Anim. sci ; 33(4): 395-401, 2011. tab, graf
Article in Portuguese | VETINDEX | ID: biblio-1399881

ABSTRACT

O objetivo deste estudo foi avaliar a inclusão de substâncias húmicas na dieta sobre o desempenho e o desenvolvimento ruminal de bezerros leiteiros da raça Holandesa. Foram utilizados 20 animais em delineamento experimental em blocos completos aleatorizados, distribuídos nos seguintes tratamentos: 1) controle; 2) substâncias húmicas, via concentrado inicial. Os animais receberam 4 L d-1 da dieta líquida e concentrado inicial ad libitum. Diariamente foram realizadas análise de escore fecal, e semanalmente foram realizadas pesagens, medidas de crescimento corporal e colheita de sangue para a determinação de glicose, N-ureico e ß-hidroxibutirato (BHBA). Os animais foram desaleitados na oitava semana de idade e foram abatidos para análise do desenvolvimento do trato digestório superior. Não houve efeito significativo (p > 0,05) entre os tratamentos ou interação tratamento x idade para os parâmetros consumo de concentrado, ganho de peso, medidas de crescimento corporal e parâmetros sanguíneos. Entretanto, foi observado efeito de idade (p < 0,0001) para todos os parâmetros avaliados. O escore fecal e o desenvolvimento ruminal também não foram afetados pelos tratamentos (p > 0,05). Não houve efeito da inclusão de substâncias húmicas na dieta quanto ao desempenho e desenvolvimento ruminal de bezerros leiteiros.


The objective of this work was to evaluate the inclusion of humic substances in starter concentrate on the performance of dairy calves and rumen development. Twenty Holstein calves were used in a completely randomized block design and distributed in two treatments according to inclusion of humic substances in concentrate: 1) Control; 2) Humic substances. Animals received 4 L d-1 liquid diet and starter concentrate ad libitum. Fecal score analyses were carried out daily, and calves were weighed weekly and growth measurements and blood samples for glucose, urea-N and ß-hidroxibutyrate (BHBA) were taken. The calves were weaned at eight weeks of age and slaughtered for evaluation of forestomach development. There were no effects (p > 0.05) between treatments or treatment x age interaction for concentrate intake, weight gain, growth measurements or blood parameters. Fecal scores and rumen development were not affected (p > 0.05) by the inclusion of humic substances. There were no benefits from the inclusion of humic substances in starter concentrate on performance or rumen development of dairy calves.


Subject(s)
Animals , Cattle , Weaning , Cattle , Humic Substances
9.
Ciênc. agrotec., (Impr.) ; 32(6): 1760-1766, nov.-dez. 2008. tab
Article in Portuguese | LILACS | ID: lil-508574

ABSTRACT

Avaliou-se, neste estudo, o efeito da aplicação de adubos orgânicos, minerais e calagem, nas frações húmica, fúlvica e nos teores de carbono orgânico de um Latossolo Vermelho e de um Cambissolo, cultivados com alface (americana). O experimento, realizado no Departamento de Ciência do Solo da Universidade Federal de Lavras, foi constituído de cinco doses de material húmico (0, 20, 40, 100 e 200 L ha-1), três tipos de adubação (composto orgânico, esterco de aves e mineral) e calagem (com e sem uso de calcário), em cinco repetições. No Cambissolo, a calagem contribuiu para a diminuição do teor de C orgânico nas áreas adubadas com fertilizante mineral e composto, e aumentou o armazenamento de C no solo adubado com esterco de aves. Em relação à adubação mineral, o uso de adubo orgânico aumentou os teores de C-fração ácido húmico e a relação C-húmico/fúlvico. No Latossolo, independente do tipo de adubação, o uso da calagem propiciou o armazenamento no solo de mais C do que o observado na área sem correção da acidez. Os efeitos da calagem e das fontes de nutrientes variaram em função da fração orgânica analisada ou das relações entre seus teores de carbono.


This study evaluated the effects of organic and mineral fertilizers and liming, on humic, fulvic, and organic carbon fractions of an Inceptisol and an Oxisol grown with lettuce. The experiment was carried out at the Soil Science Department of Federal University of Lavras, Minas Gerais state, Brazil. It was performed with 5 levels of soil conditioner (0, 20, 40, 100, 200 L ha-1), 3 fertilizers (organic compost, chicken manure and mineral), and liming (present or absent) using five replications. In the Inceptisol essay, the liming contributed to a decrease in the organic-C content in the mineral and compost fertilized plots, and increased C-accumulation in the treatments under chicken manure. The organic fertilizer increased the content of C-humic acid and the relation Chumic/fulvic. In the Oxisol essay, the liming contributed to C-accumulation when related to the treatments without liming. Liming effects and fertilizers varied as a function of the analyzed organic fractions and C content.

10.
Rev. colomb. quím. (Bogotá) ; 35(2): 191-203, jul.-dic. 2006. ilus, graf, tab
Article in Spanish | LILACS | ID: lil-636592

ABSTRACT

Para evaluar y comparar algunas propiedades de los ácidos húmicos (AH) y fúlvicos (AF) como el grado de condensación y polimerización, el contenido total de carbono, hidrógeno y nitrógeno, y sus constantes de acidez, se analizó la fracción menor a 50 µm de un Mollisol del horizonte Ap, bajo caña de azúcar, y se comparó con un horizonte A, bajo bosque. Para tal fin se hicieron extracciones sucesivas con tetraborato de sodio 0,05 M, pirofosfato de sodio 0,025 M e hidróxido de sodio 0,1M. Las sustancias húmicas se purificaron mediante tratamientos con ácidos inorgánicos en solución al 1% de HCl y HF, resinas de absorción Amberlita XAD-16 e intercambio catiónico R101H+, diálisis y liofilización, y se caracterizaron por análisis elemental, relación E4/E6 y potenciometría ácido-base de acuerdo con las funciones de Gran modificadas. La relación E4/E6 permitió establecer mayores tamaños moleculares y grado de condensación de los ácidos húmicos en relación con los ácidos fúlvicos. Por potenciometría ácido-base se determinaron, en los ácidos húmicos y ácidos fúlvicos, las concentraciones de grupos funcionales ácidos y sus respectivas constantes de acidez. Dos de éstas, tituladas entre pH 4,0 y 6,1 corresponden a grupos carboxílicos, las otras dos entre pH 7,2 y 8,7 son el resultado de grupos -OH fenólicos fuertes y carboxílicos débiles. En el horizonte Ap, bajo caña de azúcar, los resultados demostraron que las prácticas de uso y manejo de este cultivo han llevado a la homogeneización de las sustancias húmicas, mientras que en el horizonte A bajo bosque existen ácidos húmicos y fúlvicos diferenciados por tamaño molecular, aromaticidad y grado de humificación.


In order to determine and to compare some physicochemical properties of humic (HA) and fulvic (FA) acids such as degree of condensation and polymerization, the total C,H,N content and pKa values were analyzed in the smaller fraction (< 50 m) from Ap horizon under sugarcane crop in opposition to A horizon under forest, both Mollisol order. To carry out this aim, successive extractions with sodium tetraborate 0.05 M, sodium pyrophosphate 0.025 M, and sodium hydroxide 0.1 M were made. The purification of these humic substances by treatment with inorganic acids 1% solutions of HCl and HF, Amberlite XAD-16 adsorption resin and R 101H+ cationic exchange, dialysis and freeze driying were done. The humic and fulvic acids were characterized by elemental analysis, E4/E6 relation and acid-base potentiometry. The ratio E4/E6 allows to establish that molecular size and degree of condensation in humic acids were bigger than in fulvic acids. By means of acid-base potentiometry, the concentrations of functional acid groups and their acid constants in the humic and fulvic acids were determined. Four constants were found; first and second between pH 4.0 and 6.1 correspond to differents kinds of carboxyl groups and another two between pH 7.2 and 8.7 come from strong O-H phenolic and weak carboxyl groups. In the Ap horizon under sugarcane the characterization showed that the handling and land use practices promote the homogeneity of humic substances meanwhile in the A horizon under forest; the humic and fulvic acids are different due to their degree of condensation molecular size and humification index.

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