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1.
Braz J Biol ; 83: e270966, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37283336

RESUMO

Terpenoids, also named terpenes or isoprenoids, are a family of natural products found in all living organisms. Many plants produce terpenoids as secondary metabolites, and these make up a large part of essential oils. One of most important characteristic is that the compounds are volatile, have odor and can be used in a variety of applications in different industrial segments and traditional medicine. Brazil has a rich and diverse flora that can be used as a source of research for obtaining new molecules. Within the Brazilian flora, it is worth mentioning the Caatinga as an exclusively Brazilian biome where plants adapt to a specific series of weather conditions and therefore become a great storehouse of the terpenoid compounds to be described herein. Fungal infections have become increasingly common, and a great demand for new agents with low toxicity and side effects has thus emerged. Scientists must search for new molecules exhibiting antifungal activity to develop new drugs. This review aims to analyze scientific data from the principal published studies describing the use of terpenes and their biological applications as antifungals.


Assuntos
Óleos Voláteis , Terpenos , Terpenos/farmacologia , Terpenos/metabolismo , Antifúngicos/farmacologia , Brasil , Óleos Voláteis/farmacologia , Plantas
2.
Animal ; 16 Suppl 3: 100538, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35644846

RESUMO

Sustainable intensification of tropical grasslands has been identified by researchers and stakeholders as a solution to decrease greenhouse gas emissions and deforestation. However, there are concerns about food security and the role of livestock in feed-food competition between animals and humans involving land and other resources. We aimed to determine the net protein contribution (NPC), a feed-food competitiveness index, of tropical beef cattle raised on extensive systems or finished in pastures or conventional feedlots, under different levels of intensification. We modelled five scenarios, from cow-calf to slaughter, based on common beef cattle practices in Brazil, whose main production system is grazing. Scenario 1 represented the lowest level of intensification and the most extensive system. Scenario 2 represented a moderately extensive system. Scenarios 3, 4, and 5 represented different degrees and practices of intensification, with animals in cow-calf and stocker phases raised solely on well-managed permanent pastures. In Scenario 3, the animals were finished in a feedlot. In Scenarios 4 and 5, all animals in the stocker phase received a protein-energy supplement, but in Scenario 4, animals were finished in a permanent pasture with high-concentrate intake. In Scenario 5, animals were finished in a feedlot. The human-edible protein (heP) conversion efficiency (hePCE) was calculated as the ratio of heP produced (meat) to heP consumed as feed, and the NPC was the product of hePCE using the protein quality ratio, accounting for the digestible indispensable amino acid score content. An hePCE > 1 indicated that meat production did not compete with humans for food, and an NPC > 1 indicated that it contributed positively to meet human requirements. Meat production and heP intake consistently increased with intensification. The greatest hePCE values were from Scenarios 1 (9.2), 2 (2.2), and 3 (1.2), which were essentially pasture-fed systems, compared to Scenarios 4 and 5 (average of 1.0). The NPC varied from 24.1 (Scenario 1) to 2.6 (Scenario 5). The area required to produce 1 kg of carcass decreased from 147 to 45 m2, and the slaughter age decreased from 36 to 21 months from the most extensive to intensive systems. Brazilian beef cattle production contributes positively to the protein requirements of humans without limiting human food supplies. The intensification of tropical grazing beef systems is a key strategy to save land and produce more meat without limiting food for humans, playing an important role in the food security agenda.


Assuntos
Ração Animal , Gases de Efeito Estufa , Ração Animal/análise , Criação de Animais Domésticos , Animais , Bovinos , Suplementos Nutricionais , Feminino , Humanos , Carne
3.
Rev. bras. plantas med ; 16(3,supl.1): 771-782, 2014. tab
Artigo em Português | LILACS | ID: lil-727208

RESUMO

O uso de espécies vegetais como fonte terapêutica e alimentícia tem apresentado significativo crescimento nos últimos anos, em especial no território brasileiro que é dotado de grande biodiversidade. A regulamentação dessas categorias de produtos envolve uma vasta lista de legislações, o que gera dificuldades no entendimento regulatório. Este trabalho teve por objetivo diferenciar algumas das classes de alimentos e medicamentos baseados em espécies vegetais e expor as legislações pertinentes a cada caso. Foi realizado um levantamento bibliográfico e documental com base no acervo regulatório brasileiro atual e os principais dados foram compilados em forma de tabela. Este trabalho permitiu visualizar uma parte do universo legal referente aos produtos de origem vegetal, o que é essencial para o enquadramento correto dessas espécies frente a legislação, bem como seu comércio, propaganda e uso regular e seguro. Isto é fundamental frente à valorização emergente das espécies vegetais dentro do sistema público de saúde brasileiro de acordo com as exigências regulatórias de cada categoria.


The use of plant species as food and therapy source has shown significant growth in recent years, particularly in the Brazilian territory that is endowed with rich biodiversity. The regulation of these product categories, however, involves a wide range of legislation, which creates difficulties in regulatory understanding. This study aimed to differentiate some of the classes of food and medicines based on plant species and expose the laws pertaining to each case. We conducted a literature review and documentary based on the current Brazilian regulatory collection and the most important data were compiled in tabular form. This work allowed us to visualize a part of the legal universe for products of plant origin, which is essential for the adequate framing of these species in the legislation, as well their regular and safe trade, marketing and use. This is necessary because of the major regulations and requirements for food and medication categories and the emerging appreciation of plant species on the Brazilian public health system.


Assuntos
Legislação , Medicamento Fitoterápico , Alimentos/estatística & dados numéricos , Plantas/efeitos adversos , Plantas Medicinais/classificação , Diretório
4.
Braz J Med Biol Res ; 36(4): 503-9, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12700829

RESUMO

We studied the effects of ethanol on the levels of norepinephrine, dopamine, serotonin (5-HT) and their metabolites as well as on D1- and D2-like receptors in the rat striatum. Ethanol (2 or 4 g/kg, po) was administered daily by gavage to male Wistar rats and on the 7th day, 30 min or 48 h after drug administration, the striatum was dissected for biochemical assays. Monoamine and metabolite concentrations were measured by HPLC and D1- and D2-like receptor densities were determined by binding assays. Scatchard analyses showed decreases of 30 and 43%, respectively, in D1- and D2-like receptor densities and no change in dissociation constants (Kd) 48 h after the withdrawal of the dose of 4 g/kg. Ethanol, 2 g/kg, was effective only on the density of D2-like receptors but not on Kd of either receptor. Thirty minutes after the last ethanol injection (4 g/kg), decreases of D2 receptor density (45%) as well as of Kd values (34%) were detected. However, there was no significant effect on D1-like receptor density and a 46% decrease was observed in Kd. An increase in dopamine and 3,4-dihydroxyphenylacetic acid (DOPAC), a decrease in norepinephrine, and no alteration in 5-HT levels were demonstrated after 48-h withdrawal of 4 g/kg ethanol. Similar effects were observed in dopamine and DOPAC levels 30 min after drug administration. No alteration in norepinephrine concentration and a decrease in 5-HT levels were seen 30 min after ethanol (4 g/kg) administration. Our findings indicate the involvement of the monoaminergic system in the responses to ethanol.


Assuntos
Monoaminas Biogênicas/metabolismo , Depressores do Sistema Nervoso Central/farmacologia , Corpo Estriado/efeitos dos fármacos , Etanol/farmacologia , Receptores de Dopamina D1/efeitos dos fármacos , Receptores de Dopamina D2/efeitos dos fármacos , Animais , Cromatografia Líquida de Alta Pressão , Corpo Estriado/metabolismo , Dopamina/metabolismo , Masculino , Norepinefrina/metabolismo , Ratos , Ratos Wistar , Receptores de Dopamina D1/metabolismo , Receptores de Dopamina D2/metabolismo , Serotonina/metabolismo
5.
Braz. j. med. biol. res ; 36(4): 503-509, Apr. 2003. tab, graf
Artigo em Inglês | LILACS | ID: lil-331234

RESUMO

We studied the effects of ethanol on the levels of norepinephrine, dopamine, serotonin (5-HT) and their metabolites as well as on D1- and D2-like receptors in the rat striatum. Ethanol (2 or 4 g/kg, po) was administered daily by gavage to male Wistar rats and on the 7th day, 30 min or 48 h after drug administration, the striatum was dissected for biochemical assays. Monoamine and metabolite concentrations were measured by HPLC and D1- and D2-like receptor densities were determined by binding assays. Scatchard analyses showed decreases of 30 and 43 percent, respectively, in D1- and D2-like receptor densities and no change in dissociation constants (Kd) 48 h after the withdrawal of the dose of 4 g/kg. Ethanol, 2 g/kg, was effective only on the density of D2-like receptors but not on Kd of either receptor. Thirty minutes after the last ethanol injection (4 g/kg), decreases of D2 receptor density (45 percent) as well as of Kd values (34 percent) were detected. However, there was no significant effect on D1-like receptor density and a 46 percent decrease was observed in Kd. An increase in dopamine and 3,4-dihydroxyphenylacetic acid (DOPAC), a decrease in norepinephrine, and no alteration in 5-HT levels were demonstrated after 48-h withdrawal of 4 g/kg ethanol. Similar effects were observed in dopamine and DOPAC levels 30 min after drug administration. No alteration in norepinephrine concentration and a decrease in 5-HT levels were seen 30 min after ethanol (4 g/kg) administration. Our findings indicate the involvement of the monoaminergic system in the responses to ethanol


Assuntos
Humanos , Masculino , Ratos , Corpo Estriado , Receptores de Dopamina D1 , Receptores de Dopamina D2 , Monoaminas Biogênicas , Depressores do Sistema Nervoso Central , Cromatografia Líquida de Alta Pressão , Corpo Estriado , Dopamina , Etanol , Norepinefrina , Ratos Wistar , Receptores de Dopamina D1 , Receptores de Dopamina D2 , Serotonina
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