Incorporação da Curcumina em Sistemas Nanoestruturados: Revisão

Curcumin is a polyphenolic compound extracted from the rhizome of Curcuma longa Linn with diverse pharmacological properties, such as anti-inflammatory, antioxidant, anticancer, antimicrobial, hepatoprotective, hypoglycemic, among others, being interesting to the development of products containing curcumin, which will bring health benefits. Curcumin can be used as a natural additive to replace the synthetic, as colorants, antioxidants and antimicrobials, and also due to its pharmacological properties. However, their incorporation into functional foods or food supplement is hampered by its low water solubility, susceptibility to alkaline conditions, light, heat and oxidation. Nanotechnology is an emerging field to improve the poor solubility, stability and bioavailability of curcumin. Several types of nanoparticles have been found to be suitable for the encapsulation of curcumin. This article reviews the nanostructured systems containing curcumin, like polymeric nanoparticles, solid lipid nanoparticles, liposome and nanoemulsions. Besides the nanoencapsulation techniques and physicochemical characteristics of these carriers.A curcumina é um composto polifenólico extraído do rizoma de Curcuma longa Linn com diversas propriedades farmacológicas, como anti-inflamatório, antioxidante, anticarcinogênico, antimicrobiano, hepatoprotetor, hipoglicemiante, entre outras, sendo interessante o desenvolvimento de produtos contendo curcumina, os quais trarão benefícios à saúde. A curcumina pode ser empregada como um aditivo natural em substituição aos sintéticos, como corantes, antioxidantes e antimicrobianos, e também em função de suas propriedades farmacológicas. Entretanto, a sua incorporação em alimentos funcionais ou sua utilização como suplemento alimentar é dificultada pela baixa solubilidade em água, susceptibilidade a condições alcalinas, luz, calor e oxidação. A nanotecnologia é uma área emergente para melhorar a baixa solubilidade, estabilidade e biodisponibilidade da curcumina. Vários tipos de nanopartículas têm sido encontrados como sendo adequados para a encapsulação de curcumina. Este artigo revisa os sistemas nanoestruturados contendo curcumina, como nanopartículas poliméricas, nanopartículas lipídicas sólidas, lipossomas e nanoemulsões. Além das técnicas de nanoencapsulação e características físico-químicas destes carreadores

Coacervação Complexa: Uma Técnica para a Encapsulação

Microencapsulation is the protection of a compound and modulation of its release and now, several techniques are available and among them there is the complex coacervation. The complex coacervation technique involves the association of two polymers and presents some advantages over other techniques such as the possibility of working with biopolymers, the absence of organic solvent and temperature conditions in mild processing. Functional foods containing probiotic bacteria are becoming increasingly popular in the market due to the beneficial health effects attributed to probiotics. However, these microorganisms are sensitive to various factors found in the environment that are exposed primarily to tratogastrointestinal and storage conditions. Thus, the microencapsulation is an alternative protection and controlled release for probiotics. However, factors such as temperature, pH and concentration of the hydrocolloid, particularly, can influence the formation of microcapsules. For the encapsulation of probiotics, although there are many related studies, however, according to these results, this technique can be regarded as promising for these microorganisms. Thus, this review article aims to address the key technological aspects related to microencapsulation of probiotics by the complex coacervation technique as well as the parameters related to the technique and its application potential.A microencapsulação consiste na proteção de um composto e modulação de sua liberação e, atualmente, varias técnicas estão disponíveis e entre elas destaca-se a coacervação complexa. A técnica de coacervação complexa envolve a associação de dois polímeros e apresenta algumas vantagens frente a outras técnicas como a possibilidade de se trabalhar com biopolímeros, a ausência de solvente orgânico e condições brandas de temperatura no processamento. Os alimentos funcionais contendo bactérias probióticas estão se tornando cada vez mais populares no mercado devido aos efeitos benéficos à saúde atribuídos aos probióticos. No entanto, esses microrganismos são sensíveis a vários fatores encontrados no meio em que estão expostos, principalmente ao tratogastrointestinal, bem como às condições de armazenamento. Assim, a microencapsulação surge como uma alternativa de proteção e liberação controlada para os probióticos. No entanto, fatores como temperatura, concentração dos hidrocolóides e pH, principalmente, podem influenciar na formação das microcápsulas. Para a encapsulação de probióticos, ainda não existem muitos estudos relacionados, entretanto, de acordo com resultados encontrados, essa técnica pode ser considerada promissora para esses microrganismos. Nesse sentido, este artigo de revisão, tem por objetivo abordar os principais aspectos tecnológicos relacionados à microencapsulação de probióticos pela técnica de coacervação complexa, bem como os parâmetros relacionados à técnica e seu potencial de aplicação

Microencapsulação de Culturas Probióticas: Princípios do Método de Spray Drying

Probiotic microorganisms are known to provide a number of benefits to consumer health, primarily through the maintenance of balance and composition of the gastrointestinal tract. However, for the health benefits to be achieved, should remain viable probiotics in sufficient quantity in the food until the time of consumption, in addition to being able to survive passage through the gastrointestinal tract. Due to these factors microencapsulation methods have been applied in order to protect probiotics against adverse conditions they are exposed, improving their survival. The technique of spray drying is one commonly used for encapsulation of food ingredients, it offers some advantages, such as relatively low cost, ease of operation, high production rates and possibility of application in industrial scale. In this context, the aim of this work is to provide an overview of the importance and benefits of microencapsulation of probiotic cultures emphasizing the principles of métodode spray drying.Microrganismos probióticos são conhecidos por proporcionar uma série de benefícios à saúde do consumidor, principalmente através da manutenção do equilíbrio e da composição do trato gastrointestinal. No entanto, para que os efeitos benéficos à saúde sejam alcançados, os probióticos devem permanecer viáveis e em quantidade suficiente no alimento até o momento do consumo, além de serem capazes de sobreviver à passagem pelo trato gastrointestinal. Devido a estes fatores, métodos de microencapsulação têm sido aplicados com a finalidade de proteger os probióticos contra condições adversas a que são expostos, melhorando sua sobrevivência. A técnica de spray drying é uma das mais utilizadas para a encapsulação de ingredientes alimentícios, por apresentar vantagens, como custo relativamente baixo, facilidade de operação, altas taxas de produção e possibilidade de aplicação em escala industrial. Neste contexto, o objetivo deste trabalho é fornecer uma revisão sobre a os benefícios das culturas probióticas e a importância da microencapsulação para melhorar a viabilidade destes microrganismos destacando os princípios do método de spray drying

Encapsulação de Compostos Bioativos por Coacervação Complexa

The bioactive compounds are chemicals found in plants and are widely known for bringing health benefits, so it can be designated as functional foods. However, they are sensitive to various factors found in the environment that are exposed primarily to tratogastrointestinal and, moreover, are lipophilic, therefore, have low solubility in aqueous media. In this sense, the encapsulation of these compounds is an alternative protection, and the provision of such compounds in suitable amounts. The complex coacervation microencapsulation is a technique commonly used for such compounds, besides having front advantages to other techniques such as the use of biopolymers, no use of toxic agents, among others. Currently, there are a lot of research in this direction, which will be presented in this paper. Thus, the present review aims to present the main bioactive compounds studied and encapsulated as well as the parameters for complex coacervation technique.Os compostos bioativos são substâncias químicas presentes em plantas e são amplamente conhecidos por trazerem benefícios à saúde, assim podendo ser designados como alimentos funcionais. Entretanto, são sensíveis a vários fatores encontrados no meio em que estão expostos, principalmente ao tratogastrointestinal e, além disso, são lipofílicos, assim, apresentam baixa solubilidade em meios aquosos. Nesse sentido, a encapsulação desses compostos surge como uma alternativa de proteção, bem como de fornecimento desses compostos em quantidades adequadas. A coacervação complexa é uma técnica de microencapsulação muito utilizada para esses compostos, além de apresentar vantagens frente a outras técnicas, como a utilização de biopolímeros, não utilização de agentes tóxicos, entre outros. Atualmente, existem muitas pesquisas nesse sentido, as quais serão apresentadas no decorrer deste trabalho. Dessa forma, o presente artigo de revisão tem como objetivo apresentar os principais compostos bioativos estudados e encapsulados, bem como os parâmetros referentes à técnica de coacervação complexa

Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio

Geography and ecology shape the phylogenetic composition of Amazonian tree communities

Aim: Amazonia hosts more tree species from numerous evolutionary lineages, both young and ancient, than any other biogeographic region. Previous studies have shown that tree lineages colonized multiple edaphic environments and dispersed widely across Amazonia, leading to a hypothesis, which we test, that lineages should not be strongly associated with either geographic regions or edaphic forest types. Location: Amazonia. Taxon: Angiosperms (Magnoliids; Monocots; Eudicots). Methods: Data for the abundance of 5082 tree species in 1989 plots were combined with a mega-phylogeny. We applied evolutionary ordination to assess how phylogenetic composition varies across Amazonia. We used variation partitioning and Moran\u27s eigenvector maps (MEM) to test and quantify the separate and joint contributions of spatial and environmental variables to explain the phylogenetic composition of plots. We tested the indicator value of lineages for geographic regions and edaphic forest types and mapped associations onto the phylogeny. Results: In the terra firme and várzea forest types, the phylogenetic composition varies by geographic region, but the igapó and white-sand forest types retain a unique evolutionary signature regardless of region. Overall, we find that soil chemistry, climate and topography explain 24% of the variation in phylogenetic composition, with 79% of that variation being spatially structured (R$^{2}$ = 19% overall for combined spatial/environmental effects). The phylogenetic composition also shows substantial spatial patterns not related to the environmental variables we quantified (R$^{2}$ = 28%). A greater number of lineages were significant indicators of geographic regions than forest types. Main Conclusion: Numerous tree lineages, including some ancient ones (>66 Ma), show strong associations with geographic regions and edaphic forest types of Amazonia. This shows that specialization in specific edaphic environments has played a long-standing role in the evolutionary assembly of Amazonian forests. Furthermore, many lineages, even those that have dispersed across Amazonia, dominate within a specific region, likely because of phylogenetically conserved niches for environmental conditions that are prevalent within regions

Local hydrological conditions influence tree diversity and composition across the Amazon basin

Tree diversity and composition in Amazonia are known to be strongly determined by the water supplied by precipitation. Nevertheless, within the same climatic regime, water availability is modulated by local topography and soil characteristics (hereafter referred to as local hydrological conditions), varying from saturated and poorly drained to well-drained and potentially dry areas. While these conditions may be expected to influence species distribution, the impacts of local hydrological conditions on tree diversity and composition remain poorly understood at the whole Amazon basin scale. Using a dataset of 443 1-ha non-flooded forest plots distributed across the basin, we investigate how local hydrological conditions influence 1) tree alpha diversity, 2) the community-weighted wood density mean (CWM-wd) – a proxy for hydraulic resistance and 3) tree species composition. We find that the effect of local hydrological conditions on tree diversity depends on climate, being more evident in wetter forests, where diversity increases towards locations with well-drained soils. CWM-wd increased towards better drained soils in Southern and Western Amazonia. Tree species composition changed along local soil hydrological gradients in Central-Eastern, Western and Southern Amazonia, and those changes were correlated with changes in the mean wood density of plots. Our results suggest that local hydrological gradients filter species, influencing the diversity and composition of Amazonian forests. Overall, this study shows that the effect of local hydrological conditions is pervasive, extending over wide Amazonian regions, and reinforces the importance of accounting for local topography and hydrology to better understand the likely response and resilience of forests to increased frequency of extreme climate events and rising temperatures

Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5,6,7 vast areas of the tropics remain understudied.8,9,10,11 In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepresented in biodiversity databases.13,14,15 To worsen this situation, human-induced modifications16,17 may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple organism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region's vulnerability to environmental change. 15%–18% of the most neglected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lost

Mapping density, diversity and species-richness of the Amazon tree flora

Using 2.046 botanically-inventoried tree plots across the largest tropical forest on Earth, we mapped tree species-diversity and tree species-richness at 0.1-degree resolution, and investigated drivers for diversity and richness. Using only location, stratified by forest type, as predictor, our spatial model, to the best of our knowledge, provides the most accurate map of tree diversity in Amazonia to date, explaining approximately 70% of the tree diversity and species-richness. Large soil-forest combinations determine a significant percentage of the variation in tree species-richness and tree alpha-diversity in Amazonian forest-plots. We suggest that the size and fragmentation of these systems drive their large-scale diversity patterns and hence local diversity. A model not using location but cumulative water deficit, tree density, and temperature seasonality explains 47% of the tree species-richness in the terra-firme forest in Amazonia. Over large areas across Amazonia, residuals of this relationship are small and poorly spatially structured, suggesting that much of the residual variation may be local. The Guyana Shield area has consistently negative residuals, showing that this area has lower tree species-richness than expected by our models. We provide extensive plot meta-data, including tree density, tree alpha-diversity and tree species-richness results and gridded maps at 0.1-degree resolution