A carregar...
18 resultados
Resultados da pesquisa
A mostrar 1 - 10 de 18
- MycosterolsPublication . Uber, Thaís Marques; Backes, Emanueli; Corrêa, Rúbia C.G.; Corrêa, Vanesa G.; Bracht, Adelar; Peralta, Rosane M.Sterols are amphipathic lipids that play essential roles in the physiology of eukaryotic organisms in general. The fungal sterols are collectively known as mycosterols and they exert numerous physiological functions. For humans, the interest on this class of compounds relies heavily on the fact that they can promote health benefits. For this reason, fungal extracts rich in sterols of various forms are valuable and promising ingredients. One of the best-known benefits of mycosterols is their inhibitory actions on cholesterol absorption and biosynthesis, but there are several interesting regulatory and modulatory phenomena that mycosterols can affect and that might eventually be of therapeutic interest. Within this domain, the practical application of mycosterols or mycosterol-enriched fungal extracts presents several challenges. The latter include isolation of novel bioactive mycosterols from still underexploited fungi species, the optimization of existing methodologies for production and recovery, extensive study of their applications and, finally, substantial clinical trials for attesting their health benefits and safety.
- Blueberry juice as a nutritious and bioactive beverage to be included in novel food productsPublication . Backes, Emanueli; Saldanha, Ana Luísa; Molina, Adriana K.; Pereira, Carla; Dias, Maria Inês; Ferreira, Isabel C.F.R.; Barros, LillianBlueberry ( Vaccinium myrtillus L.) is a very popular fruit, native from the northern hemisphere and consumed worldwide. It has been widely studied for being a rich source of bioactive compounds with recognized beneficial properties for Human health [1]. Therefore, several industrialized products, such as juices and derivatives, have been developed from blueberry fruit, aiming at most practical forms of consumption. In this sense, the present work aimed to analyse the blueberry juice in terms of nutritional value, following AOAC procedures, and chemical compositions, namely in free sugars, by HPLC-RI, organic acids, by UFLC-PDA, and phenolic compounds, by HPLC-DAD/ESI-MS. Moreover, the antioxidant capacity, by TBARS and OxHLIA assays, was also assessed to validate its bioactive properties. Regarding the nutritional value, carbohydrates were the major macronutrients found in blueberry juice, followed by ash and protein. In terms of free sugars, fructose and glucose were detected, with a higher concentration of fructose. Four organic acids were also identified in the juice, namely oxalic, quinic, malic, and shikimic acids, being quinic acid the most abundant one. In what concerns the phenolic composition, four phenolic acids (quinic acid, caffeic acid hexoside, cis 5- O- caffeoylquinic acid, and trans 5- O -caffeoylquinic acid) and six anthocyanins (cyanidin-3- O -glucoside, cyanidin-3- O -pentoside, peonidin-3- O glucoside, peonidin-3- O -pentoside, malvidin-3- O -glucoside, and malvidin-3- O -pentoside) were detected. As expected, considering its chemical composition, the juice also presented a strong antioxidant capacity, being able of inhibiting the lipid peroxidation and the oxidative hemolysis. The results obtained in the present study validate the nutritional and bioactive quality of the juice obtained from Vaccinium myrtillus L., justifying its application in the development of novel foodstuff.
- Ficus carica L. and Prunus spinosa L. extracts as new anthocyanin-based food colorants: a thorough study in confectionery productsPublication . Backes, Emanueli; Leichtweis, Maria Gabriela; Pereira, Carla; Carocho, Márcio; Barreira, João C.M.; Genena, Aziza Kamal; Baraldi, Ilton J.; Barreiro, M.F.; Barros, Lillian; Ferreira, Isabel C.F.R.The present work describes the evaluation of fig peels and blackthorn fruit extracts as natural purple colorants in doughnuts (icing) and in a typical Brazilian pastry called “beijinho”. The extracts were screened for their antioxidant activity as well as their antibacterial capacity. Nutritionally, the employed extracts did not induce significant changes, contrarily to the observed for the rheological features, mainly the darker purple tone observed when blackthorn extract was used in the icing solution. After 24 h, both prepared formulations showed a decrease in color intensity, with no significant differences between fig and blackthorn extracts. In turn, the firmness and consistency of the doughnuts benefited from using natural colorants in the icing solution, while “beijinhos” became softer and chewier, which are valued attributes. A significant increase in the antioxidant and antimicrobial activities was also observed for both natural extracts. Accordingly, the evaluated extracts are promising candidates as natural food colorants.
- A critical appraisal of the most recent investigations on the hepatoprotective action of brazilian plantsPublication . Garcia-Manieria, Jéssica A.A.; Correa, Vanesa G.; Backes, Emanueli; Sa-Nakanishi, Anacharis Babeto de; Bracht, Lívia; Comar, Jurandir Fernando; Corrêa, Rúbia C.G.; Peralta, Rosane M.; Bracht, AdelarConventional treatments for liver diseases are often burdened by side effects caused by chemicals. For minimizing this problem, the search for medicines based on natural products has increased. The objective of this review was to collect data on the potential hepatoprotective activity of plants of the Brazilian native flora. Special attention was given to the modes of extraction, activity indicators, and identification of the active compounds. The databases were Science direct, Pubmed, and Google Academic. Inclusion criteria were: (a) plants native to Brazil; (b) studies carried out during the last 15 years; (c) high-quality research. A fair number of communications met these criteria. Various parts of plants can be used, e.g., fruit peels, seeds, stem barks, and leaves. An outstanding characteristic of the active extracts is that they were mostly obtained from plant parts with low commercial potential, i.e., by-products or bio-residues. The hepatoprotective activities are exerted by constituents such as flavonoids, phenolic acids, vitamin C, phytosterols, and fructose poly- and oligosaccharides. Several Brazilian plants present excellent perspectives for the obtainment of hepatoprotective formulations. Very important is the economical perspective for the rural producers which may eventually increase their revenue by selling increasingly valued raw materials which otherwise would be wasted.
- Recuperação de antocianinas de biorresíduos de Ficus carica L. e Prunus spinosa L.: propriedades corantes e bioativasPublication . Backes, Emanueli; Leichtweis, Maria Gabriela; Pereira, Carla; Alves, Maria José; Prieto Lage, Miguel A.; Barreiro, M.F.; Barros, Lillian; Ferreira, Isabel C.F.R.A recuperação de biorresíduos da indústria alimentar tem vindo a ganhar relevância pela crescente procura da sua valorização enquanto fontes de compostos de interesse para posterior aplicação em diversos ramos industriais, como é o caso da indústria alimentar, têxtil, e farmacêutica, entre outras [1,2]. Assim, o presente estudo visa a recuperação de antocianinas a partir de biorresíduos de frutos: a casca de figo, rica em cianidina 3-rutinósido (C3R), e o epicarpo de abrunho, rico em C3R e peonidina 3-rutinósido (P3R). Foram testadas duas técnicas de extração, maceração (EM) e assistida por ultrassons (EAU), às quais se aplicou uma metodologia de superfície de resposta usando o desenho composto central circunscrito com cinco níveis em cada uma das variáveis independentes estudadas (tempo, proporção de água-etanol como solvente e temperatura (EM) ou potência (EAU)). O perfil de antocianinas dos diferentes extratos foi obtido por HPLC-DAD-ESI/MS e utilizou-se a concentração total de antocianinas (C) no resíduo de extração (R; mg C/g R) e na amostra desidratada (A; mg C/g A) e o rendimento de resíduo obtido (g R/g A) como respostas para o modelo. Foi ainda avaliada a bioatividade (citotoxicidade e atividade antioxidante e antimicrobiana) dos extratos obtidos em condições ótimas, bem como o poder corante dos mesmos avaliados pela incorporação do extrato ótimo em produtos de pastelaria. Para ambas as amostras, a EAU revelou ser a técnica mais eficiente, com condições ótimas de recuperação de C3R aos 21,3±0,6 min, 310±26 W e 100±1% de etanol no caso da casca de figo, com um rendimento de 0,5±0,2 g R/g A e um total de antocianinas de 9,0±0,8 mg C/g R e 4,3±0,1 mg C/g A. Por sua vez, a partir do epicarpo de abrunho foi possível obter um total de C3R e P3R de 18±2 mg C/g R e 11,8±0,8 mg C/g A, e um rendimento de 0,69±0,02 g R/g A, nas condições ideais de extração de 5,0±0,2 min, 400±32 W e 48±3% de etanol. Relativamente às propriedades bioativas, o extrato de casca de figo revelou um valor de EC50 de 2447±2 μg/mL no método TBARS e valores de EC80 de 515±31 e 1624±56 μg/mL, para 60 e 120 min, respetivamente, no ensaio OxHLIA. O extrato de epicarpo de abrunho apresentou valores de EC50 (TBARS; 204,22±0,02 μg/mL) e EC80 (OxHLIA; 303±3 e 540±3 μg/mL, para 60 e 120 min, respetivamente) inferiores, o que indica uma maior atividade antioxidante em ambos os ensaios. Ambos os extratos revelaram propriedades antibacterianas, inibindo o crescimento de 9 estirpes bacterianas (5 Gram-negativo e 4 Grampositivo), em concentrações entre 2,5 e 20 mg/mL. Para além disso, não apresentaram toxicidade em células não tumorais de fígado de porco, o que torna viável a sua aplicação em produtos alimentares sem problemas de toxicidade. Assim, o poder corante dos extratos antociânicos foi testado em produtos de pastelaria: o extrato de casca de figo foi incorporado em cobertura de “donut” e o de epicarpo de abrunho em “beijinhos”, um doce típico do Brasil. Esta aplicação não alterou significativamente o valor nutricional das matrizes em estudo e, para além de conferir ao alimento a cor desejada, proporciona também propriedades antioxidantes e antimicrobianas.
- Blueberry (Vaccinium myrtillus L.) juice and bagasse for antioxidant products developmentPublication . Backes, Emanueli; Molina, Adriana K.; Pereira, Carla; Dias, Maria Inês; Ferreira, Isabel C.F.R.; Barros, LillianBlueberry, Vaccinium corymbosum L., is a fruit consumed worldwide and considered one of the most antioxidant fruits [1]. Its pulp, seeds, and peel contain different chemical compounds responsible for its beneficial properties for human health [2]. This knowledge has led to the development of different industrialized products, such as juices and derivatives, in search of more practical forms of consumption. However, in the manufacture of these products, a large amount of waste is generated and has no further application, generating an environmental problem and a high cost for the industry [3]. In this context, this study aimed to evaluate the blueberry juice in terms of bioactive properties (antioxidant and antimicrobial), nutritional value (AOAC methods), free sugars (HPLC-RI), organic acids (UFLC-PDA), and phenolic (HPLC-DAD/ESI-MS) composition. Moreover, the hydroethanolic extract of blueberry bagasse, resulting from juice production, was also analyzed regarding its phenolic composition and bioactivity, to assess its applicability as source of added-value molecules to be used in food industry. The blueberry juice presented a balanced nutritional value, with carbohydrates as the main macronutrients. The free sugars found in higher concentrations were fructose and glucose. Four organic acids were also identified, with quinic acid as the most abundant. As for the phenolic composition of the juice, four phenolic acids and six anthocyanins were detected. With respect to bagasse, eight anthocyanin compounds were identified in significant amounts, with cyanidin-3- O-glucoside and malvidin-3-O-glucoside being the most abundant compounds, and four non- anthocyanin compounds, with a prevalence of cis 5-O-caffeoylquinic acid and trans 5-O- caffeoylquinic. Concerning the bioactive properties, as expected considering their chemical composition, both the juice and the bagasse extract revealed a strong antioxidant capacity, being able to inhibit lipid peroxidation and oxidative hemolysis. None of the two showed cytotoxic properties, being considered safe for food consumption. Thus, this study validated the nutritional and bioactive quality of blueberry juice and justified the application of bagasse in the development of novel foods.
- Overproduction of laccase by trametes versicolor and Pycnoporus sanguineus in farnesol-pineapple waste solid fermentationPublication . Backes, Emanueli; Kato-Schwartz, Camila Gabriel; Oliveira Junior, Verci A. de; Uber, Thaís Marques; Santos, Luís F. O. dos; Corrêa, Rúbia C.G.; Bracht, Adelar; Peralta, Rosane M.The effect of farnesol, a sesquiterpene alcohol, on the production of laccases by Trametes versicolor and Pycnoporus sanguineus in pineapple waste solid-state fermentation was evaluated. Extracellular laccase production reached a maximum of 77.88 5.62 U/g (236% above control) in farnesol-induced cultures of T. versicolor on the 17th day, whereas in a similar P. sanguineus culture, a maximal laccase activity of 130.95 2.20 U/g (159% increase) was obtained on the 17th day. A single 45KDa laccase was produced by both fungi under the influence of farnesol. These and other data allow us to conclude that farnesol acted as an inducer of the same form of laccase in both fungi. Farnesol disfavored fungal growth by increasing the lag phase, but it also clearly improved the oxidative state of the cultures. Contrary to the results obtained previously in submerged cultures, farnesol did not promote hyperbranching in the fungal mycelia. This is the first demonstration that farnesol is an excellent inducer of laccases in T. versicolor and P. sanguineus in solid-state cultivation. In quantitative terms, the results can be regarded as an excellent starting point for developing industrial or at least pre-industrial procedures to produce laccases using T. versicolor and P sanguineus under the stimulus of farnesol.
- Laccases in food processing: Current status, bottlenecks and perspectivesPublication . Backes, Emanueli; Kato-Schwartz, Camila Gabriel; Corrêa, Rúbia C.G.; Moreira, Regina de Fátima Peralta Muniz; Peralta, Rosely Aparecida; Barros, Lillian; Ferreira, Isabel C.F.R.; Zanin, Gisella Maria; Bracht, Adelar; Peralta, Rosane M.Background: Laccases (benzenediol:oxygen oxidoreductases, EC 1.10.3.2) catalyze the oxidation of a wide variety of organic and inorganic substrates, typically p-diphenols with a concomitant reduction of oxygen (O2) to water. Several molecules naturally occurring in foods and beverages (e.g., phenols, carbohydrates, unsatured fatty acids and thiol-containing proteins) can be modified by laccases. Hence, the interaction between laccase and these molecules can and has been widely explored by the food industry for various technological purposes. Scope and approach: The present work aims at providing a critical review on the current uses of laccases in food processing, at discussing the main bottlenecks for its popularization, and at presenting future perspectives. Both scientific reports and patents, covering preferably the last five years, were considered. Key findings and conclusions: Several traditional uses of laccases in food processing including baking, beverage, and dairy industries were detailed. Special efforts were developed, however, in analyzing future perspectives. The latter includes the application of laccases in the synthesis of new compounds with functional properties, such as antioxidant and antimicrobial activities. No less attention was devoted to the recent developments in the field of crosslinking of polymers, such as proteins and polysaccharides. Scaling up of the production of the laccase itself and especially of the novel products derived from its applications in the food sector will be essential for cost reduction and, consequently, for market expansion.
- Valorização da casca de Ficus carica L. como fonte de pigmentos naturais: estudos de extração, caracterização química e biológica e incorporação em alimentosPublication . Backes, Emanueli; Ferreira, Isabel C.F.R.; Barreiro, M.F.; Genena, Aziza KamalDevido à sua coloração, a casca do figo, infrutescência da figueira (Ficus carica L.), pode ser considerada como fonte potencial de antocianinas. Neste contexto, o objetivo deste estudo consistiu na comparação de diferentes técnicas de extração (assistidas por calor, ultrassons e micro-ondas) para a recuperação de antocianinas. Adicionalmente, e para as condições ótimas de extração, o extrato obtido foi caracterizado quanto à composição química e propriedades bioativas (atividades antioxidante, antimicrobiana, anti-inflamatória e citotóxica). A fim de obter as condições que maximizam a extração de antocianinas, foi utilizada a metodologia de superfície de resposta usando um delineamento composto central circunscrito de três variáveis com cinco níveis. As variáveis relevantes testadas e otimizadas neste estudo foram o tempo, temperatura e composição do solvente (razão etanol/água) para os métodos de extração assistidos por calor e micro-ondas. Para o método de ultrassons a temperatura foi mantida constante enquanto a potência ultrassônica foi a variável estudada, juntamente com o tempo e a composição do solvente. A composição em antocianinas foi determinada por HPLC-DAD-ESI/MS e as respostas utilizadas como critérios foram: quantificação da cianidina-3-rutinósido (C) no resíduo extraído (R; mg C/g R) e na casca do figo (P; mg C/g P dw) e a relação de ambas (g R/g P dw). A extração ultrassónica mostrou ser o método mais eficaz, conduzindo a extração de 7,0 ± 0,2 mg C/g R, 3,11 ± 0,05 mg C/g P dw e 0,19 ± 0,001 g R/g P dw nas condições ótimas globais de extração (21 min e 310 W com 100% de etanol e 180 g/L). Em relação às propriedades bioativas, o extrato otimizado de casca de figo apresentou atividade antioxidante com EC50 de 2,447 mg/mL pelo método de TBARS e EC80, em 60 min (EC80 (60 min)) e em 120 min (EC80 (120 min)) de 0,52 e 1,62 mg/mL, respetivamente pelo método OxHLIA. O extrato revelou, para diferentes bactérias Gram-positivo e Gram-negativo, atividade antimicrobiana, além de não apresentar citotoxicidade para células não tumorais. Porém, não apresentou atividade anti-inflamatória ou citotóxica para células tumorais humanas. O estudo da sua aplicação num produto alimentar foi efetuado tendo como objetivo a preparação de coberturas para donuts (glacê). Em síntese, os resultados obtidos colocam em evidência a potencial aplicação da casca de F. carica como fonte de antocianinas para diferentes setores industriais, nomeadamente alimentar, farmacêutico e cosmético, agregando os benefícios provenientes da sua atividade antioxidante e antimicrobiana ao seu poder corante.
- Exploring the α-amylase-inhibitory properties of tannin-rich extracts of Cytinus hypocistis on starch digestionPublication . Correa, Vanesa G.; Garcia-Manieri, Jéssica A.A.; Silva, Ana Rita; Backes, Emanueli; Corrêa, Rúbia C.G.; Barros, Lillian; Bracht, Adelar; Peralta, Rosane M.Cytinus hypocistis (L.) L. is an edible parasitic plant that grows within the roots of its host. In addition to its use as famine food in the past, it is also tradidionally used for treating several illnesses such as intestinal problems, inflammations, tumors, and bleeding. This species is rich in hydrolysable tannins, compounds often associated with inhibiting starch digestion. Therefore, the present work investigated how effectively C. hypocistis tannin-rich extracts inhibited enzymes involved in starch digestion and if such effect also occurs in vivo. The latter premise was approached using the starch tolerance test in mice. Two optimized hydroethanolic extracts were used, a heat-assisted and an ultrasound-assisted extract, with known hydrolysable tannin content. Both extracts demonstrated potent inhibition of α-amylase. Inhibitions were of the mixed type with inhibitor constants in the 15 μg/mL range. The inhibition of the intestinal α-glucosidase was at least ten times less effective. The inhibition of the α-amylase was negatively affected by in vitro gastrointestinal digestion and bovine serum albumin. In vivo, both extracts inhibited starch digestion at doses between 100 and 400 mg/mL in healthy mice. The highest doses of the ultrasound and heat extracts diminished the peak glucose levels in the starch tolerance test by 46 and 59.3%, respectively. In streptozotocin diabetic mice, this inhibition occurred only at the dose of 400 mg/mL. Under this condition, diminution of the peak glucose concentration in the starch tolerance test was equal to 36.7% and 48.8% for the ultrasound and heat extracts, respectively. Maltose digestion was not inhibited by the C. hypocistis extracts. Qualitatively and quantitatively, thus, the actions of both extracts were similar. The results allow adding a new biological property to C. hypocistis, namely, the ability to decrease the hyper-glycemic excursion after a starch-rich meal, propitiating at the same time a diminished caloric intake.