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Caracterização do fruto buritirana (Mauritiella armata Mart.) e seus coprodutos e aplicação de técnicas emergentes para a recuperação de compostos bioativos
No full textTese (doutorado) - Universidade Federal de Santa Catarina, Centro de Ciências Agrárias, Programa de Pós-Graduação em Ciência dos Alimentos, Florianópolis, 2024.A buritirana (Mauritiella armata), também é conhecida como buriti mirim, buriti bravo e yumuna aguajillo. Seus frutos possuem formatos globosos a oblongos-elipsoides, sua polpa é carnuda e fibrosa de cor avermelhada e de aroma e sabor forte e peculiar, com endocarpo muito fino que envolve uma semente dura. Seu consumo pelas populações locais se dá principalmente na forma in natura ou utilizada na elaboração de bebidas fermentadas, sucos, doces, geleias, entre outros. O objetivo deste estudo foi avaliar a composição nutricional, físico-química, os compostos bioativos e o potencial antioxidante dos extratos obtidos da polpa, casca e semente da buritirana obtidos utilizando técnicas de extração com fluídos supercríticos (SFE-CO2) e extração com líquidos pressurizados (PLE-Etanol 70% v/v) e extração com água subcrítica (SWE), comparativamente ao método convencional de Soxhlet (SOX). Além de simular a digestão gastrointestinal in vitro das partes do fruto da buritirana (polpa, casca e semente). O capítulo 1 consiste na revisão bibliográfica sobre as características botânicas da buritirana e frutos da família Arecaceae, relatando seus potenciais benefícios à saúde, processos industriais e os principais fitoquímicos reportados até o momento. No capítulo 2 foi realizada uma avaliação abrangente das propriedades químicas e físico-químicas da polpa, casca e sementes da buritirana, juntamente com o estudo do perfil fenólico e do potencial antioxidante dos extratos recuperados das partes do fruto. Os resultados indicaram alto teor lipídico e valor energético para polpa (30,53 g 100 g-1 e 351,21 kcal 100 g-1, respectivamente) e cascas (18,41 g 100 g-1 e 276,73 kcal 100 g-1, respectivamente), enquanto foram observados alto teor de fibras (63,09 g 100 g-1), amido (2,66 g 100 g-1) e carboidratos (28,60 g 100 g-1) para as sementes. Os ensaios fitoquímicos, de potencial antioxidante e de base biológica (inibição da peroxidação lipídica) demonstraram elevado potencial antioxidante para polpa e casca de buritirana. A análise LC-ESI-MS/MS permitiu a identificação de 22 compostos fenólicos na polpa e sementes de buritirana e 21 compostos fenólicos nas cascas que ainda não haviam sido relatados na literatura. O capítulo 3 teve como objetivo fornecer as primeiras informações sobre a bioacessibilidade de compostos fenólicos individuais e sobre o potencial antioxidante das frações polpa, cascas e sementes do fruto da buritirana sobre a influência da digestão gastrointestinal in vitro simulada. O perfil de compostos fenólicos identificados na polpa e nas cascas foram relativamente semelhantes. Após o processo simulado de digestão in vitro (fase intestinal), foram observadas reduções de 50,35, 73,26 e 59,55% em relação à amostra não digerida para polpa, cascas e sementes, respectivamente. A polpa apresentou redução de 72,71% em relação à amostra não digerida e bioacessibilidade de 10,64%, menor percentual bioacessível para a polpa. As cascas apresentaram redução de 81,41% e bioacessibilidade de 18,58%. Porém, independentemente do método, o potencial bioativo foi significativamente reduzido após o processo digestivo, apresentando queda acentuada entre as fases gástrica e intestinal. O capítulo 4 e 5 expôs a viabilidade do uso da extração com fluido supercrítico (SFE) e extração com líquidos pressurizados (PLE e SWE) em etapa única e em processo sequencias (SFE?PLE?SWE) para obtenção de uma fração rica em lipídeos e extratos com alto teor de fitoquímicos que apresentem potencial antioxidante a partir da polpa e cascas da buritirana. E apresentou como principais resultados que, a combinação dos processos em etapa sequencial mostrou-se eficiente para a recuperação de extratos com alto potencial antioxidante. A utilização de água como solvente em temperaturas mais elevadas, em especial na extração com água subcrítica (SWE - 130 ºC), apresentou os melhores resultados, promovendo a solubilidade dos polifenóis analisados. A quantificação do resveratrol na polpa e na casca da buritirana foi uma descoberta importante, uma vez que este composto é conhecido por seus benefícios à saúde. O capítulo 6 avaliou a extração com água subcrítica (SWE) e Soxhlet com água no conteúdo dos compostos fitoquímicos (fenólicos, flavonoides e flavonóis totais, orto-difenóis e taninos condensados), potencial antioxidante (ABTS, DPPH, FRAP, CUPRAC e CRT) e sobre o perfil fenólico individual das sementes da buritirana. Logo, o efeito da temperatura por longos períodos (Soxhlet 6 h) afetou negativamente as variáveis respostas analisadas. Os principais fenólicos individuais foram a catequina (437,76 e 110,40 µg g-1) e o ácido protocatecuico (381,60 e 109,33 µg g-1) para ambos SWE e Soxhlet, respectivamente. Logo, a escolha do método de extração, juntamente com as condições operacionais, desempenhou um papel crucial na qualidade e quantidade dos extratos obtidos. Nesse estudo, foi demonstrado pela primeira vez que as partes da buritirana (polpa, casca e semente) apresentam-se como uma boa fonte nutricional e de alto potencial bioativo, podem integrar diferentes rotas de biorrefinaria e ramos da química verde. Tanto a polpa da buritirana, como as cascas e sementes podem ser empregados na formulação de novos produtos da indústria alimentícia, química, farmacêutica e de cosmético.Abstract: Buritirana (Mauritiella armata), which is also known as buriti mirim, buriti bravo and yumuna aguajillo, has globose to oblong-ellipsoid fruits. They have fleshy and fibrous pulp with a slightly reddish color and a strong and peculiar aroma and flavor, with a very thin endocarp that surrounds a hard seed. Its consumption by local populations occurs mainly in natural form or used to make fermented drinks, juices, sweets, and jellies, among others. The objective of this study was to evaluate the nutritional, physical-chemical composition, bioactive compounds, and antioxidant potential of extracts obtained from the pulp, shell, and seed of buritirana obtained using extraction techniques with supercritical fluids (SFE-CO2) and extraction with pressurized liquids. (PLE-Ethanol 70% v/v) and subcritical water extraction (SWE), compared to the conventional Soxhlet method (SOX). In addition to simulating in vitro gastrointestinal digestion of parts of the buritirana fruit (pulp, shell, and seed). Chapter 1 consists of a bibliographic review of the botanical characteristics of buritirana and fruits from the Arecaceae family, reporting their potential health benefits, industrial processes, and the main phytochemicals already reported. In Chapter 2, a comprehensive assessment of the chemical and physicochemical properties of the buritirana pulp, shell, and seeds was carried out, together with the study of the phenolic profile and antioxidant potential of the extracts recovered from the fruit parts. The results indicated high lipid content and energy value for pulp (30.53 g 100 g-1 and 351.21 kcal 100 g-1, respectively) and shells (18.41 g 100 g-1 and 276.73 kcal 100 g-1, respectively). In comparison, high fiber content (63.09 g 100 g-1), starch (2.66 g 100 g-1), and carbohydrates (28.60 g 100 g-1) were observed for the seeds. Phytochemical, antioxidant potential, and biological-based tests (inhibition of lipid peroxidation) demonstrated high antioxidant potential for buritirana pulp and shell. The LC-ESI-MS/MS analysis allowed the identification of 22 phenolic compounds in buritirana pulp and seeds and 21 phenolic compounds in the shells that had not yet been reported in the literature. Chapter 3 aimed to provide the first information on the bioaccessibility of individual phenolic compounds and the antioxidant potential of the pulp, shell, and seed fractions of buritirana fruit on the influence of simulated in vitro gastrointestinal digestion. The profile of phenolic compounds identified in the pulp and shells were relatively similar. After the simulated in vitro digestion process (intestinal phase), reductions of 50.35, 73.26 and 59.55% were observed in relation to the undigested sample for pulp, shells, and seeds, respectively. The pulp showed a reduction of 72.71% in relation to the undigested sample and bioaccessibility of 10.64%, the lowest bioaccessible percentage for the pulp. The shells showed a reduction of 81.41% and bioaccessibility of 18.58%. However, regardless of the method, the bioactive potential was significantly reduced after the digestive process, showing a sharp drop between the gastric and intestinal phases. Chapters 4 and 5 exposed the feasibility of using supercritical fluid extraction (SFE) and pressurized liquid extraction (PLE and SWE) in single-step and sequential processes (SFE?PLE?SWE) to obtain a fraction rich in lipids and extracts with a high content of phytochemicals that have antioxidant potential from the buritirana pulp and shells. The main results were that the combination of processes in a sequential step proved to be efficient for the recovery of extracts with high antioxidant potential. The use of water as a solvent at higher temperatures, especially in extraction with subcritical water (SWE - 130 ºC), presented the best results, promoting the solubility of the analyzed polyphenols. The quantification of resveratrol in buritirana pulp and shell is an important discovery, as this compound is known for its health benefits. Chapter 6 evaluated the application of subcritical water extraction (SWE) and Soxhlet extraction with water on the content of phytochemical compounds (phenolics, flavonoids, total flavonols, ortho-diphenols, and condensed tannins), antioxidant potential (ABTS, DPPH, FRAP, CUPRAC, and CRT) and on the individual phenolic profile of buritirana seeds. Therefore, the effect of temperature for long periods (Soxhlet 6 h) negatively affected the response variables analyzed. The main individual phenolics were catechin (437.76 and 110.40 µg g-1) and protocatechuic acid (381.60 and 109.33 µg g-1) for both SWE and Soxhlet, respectively. Therefore, the choice of extraction method, together with the operating conditions, played a crucial role in the quality and quantity of the extracts obtained. In this study, it was demonstrated for the first time that the parts of buritirana (pulp, shell, and seed) are a good nutritional source with high bioactive potential and can integrate different biorefinery routes and branches of green chemistry. Both buritirana pulp, shells, and seeds can be used in the formulation of new products in the food, chemical, pharmaceutical, and cosmetic industries
Desenvolvimento de geleia de guapeva (Pouteria cf. Guardneriana Radlk) e viabilidade da inserção na alimentação escolar
Full text linkCerrado fruits have high potential for functional properties and nutritional quality, however,
the inherent seasonality of these fruits limits their consumption during the year. Thus, this
project aims to use the fruits of guapeva (Pouteria cf. guardneriana Radlk) in the form of jelly
with the substitution of commercial pectin for passion fruit albedo, focusing on the
application of this product in school food. Among the eleven formulations of guapeva jellies
proposed by the experimental design, all obtained good acceptance from the tasters,
formulation two, however, was the one that obtained the best sensory results. The stored
jellies were significantly influenced by both storage time and temperature and packaging, with
time being the variable that most interfered with the quality of jellies at the end of storage.
The useful life estimated by accelerated tests for jellies is 75 to 74 days, with low density
polyethylene packaging being the most recommended, as it maintains the most stable physical
and chemical characteristics during storage and for its low cost.Os frutos do cerrado apresentam potencial elevado quanto a propriedades funcionais e a
qualidade nutricional, porém, a sazonalidade inerente a esses frutos limita seu consumo
durante o ano. Assim, este projeto tem por objetivo o aproveitamento dos frutos da guapeva
(Pouteria cf. guardneriana Radlk) na forma de geleia com a substituição da pectina comercial
por albedo de maracujá, com foco na aplicação desse produto na alimentação escolar. Dentre
as onze formulações de geleias de guapeva propostas pelo delineamento experimental todas
obtiveram boa aceitação dos provadores, a formulação dois, entretanto foi a que obteve
melhores resultados sensoriais. As geleias armazenadas sofreram influência significativa tanto
do tempo como da temperatura de armazenamento e das embalagens, sendo o tempo a
variável que mais interferiu na qualidade das geleias ao final do armazenamento. O tempo de
vida útil estimado por testes acelerados para as geleias é de 75 a 74 dias sendo a embalagem
de polietileno de baixa densidade a mais recomendada, pois mantém mais estáveis as
características físico-químicas durante o armazenamento
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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