509 research outputs found
Microencapsulação de um extrato de rosa micrantha para utilização na área alimentar
Os extratos de plantas são fontes abundantes de compostos fenólicos com propriedades
antioxidantes reconhecidas. Dados os benefícios que aportam para a saúde humana, estes
assumem grande relevância na indústria alimentar, nomeadamente no desenvolvimento de
alimentos funcionais. No entanto, estes compostos de reconhecida instabilidade, podem sofrer
alterações durante o processamento dos alimentos onde são incorporados e processos
metabólicos. Neste contexto, a microencapsulação possibilita a proteção destes antioxidantes
naturais, permitindo ainda a sua libertação controlada1. O presente trabalho teve como objetivo
avaliar as propriedades antioxidantes do extrato hidroalcoólico de Rosa micrantha Borrer ex Sm e
do seu flavonoide maioritário, a catequina, na sua forma livre e microencapsulada quando
incorporados num iogurte natural. Para o efeito foram preparadas microesferas de alginato
utilizando uma técnica de microencapsulação por spray seguida de coagulação. O processo foi
otimizado numa primeira fase utilizando a catequina como composto modelo, sendo
posteriormente aplicada ao extrato de R. micrantha. Quando comparada com o seu homólogo
microencapsulado, a incorporação direta do extrato de R. micrantha conduziu a produtos com
atividade antioxidante inicial superior (avaliação para t=0). No entanto, os iogurtes aditivados com
o microencapsulado apresentaram uma capacidade de manutenção da atividade antioxidante
superior (avaliação para t=3 dias). No que respeita à catequina, esta apresentou uma grande
instabilidade, sendo que a sua microencapsulação pelo processo utilizado não conduziu a
melhorias significativas da preservação da sua atividade antioxidante com o tempo e quando
incorporada no iogurte.FCT pelo apoio financeiro ao CIMO (projeto
estratégico PEstOE/AGR/UI0690/2011), LSRE (projeto estratégico PEst-C/EQB/LA0020/2011) e
Lillian Barros (contrato Compromisso para a Ciência 2008); agradecem também à Professora
Doutora Ana Maria Carvalho (CIMO-ESA/IPB) pela colheita e identificação de R. micrantha
Application of spray-coagulation method to microencapsulate catechin having in view cosmetic, pharmaceutical or nutraceutical areas
Catechin is a polyphenolic compound of the flavonoid family and a product of the secondary
metabolism of various plants [1 ]. Antioxidant and chelating properties are attributed to catechin, as
well as to other flavonoids, due to their aromatic hydroxyl groups. The presence of these bioactive
components in diets rich in vegetables offers a protective effect in human health, including
prevention of cardiovascular disorders and certain cancers, and in the ageing process itself. When
ingested, catechin undergoes a process of metabolism that changes its structure affecting the
antioxidant properties [2]. Microencapsulation can be used to overcome this problem offering
protection by means of a cover material and enabling its controlled release over time or selectively
to an intended target [3].
In this study catechin was microencapsulated in an alginate matrix by using a spray-coagulation
technique. Briefly, a sodium alginate solution (4%, w/v) containing catechin was prepared under
stirring at ambient temperature by using a ratio catechin:alginate of 25:400 (w/w). The solution
was atomized in a Nisco Var J30 unit and microspheres consolidated upon contact with a solution
of CaCI2 (4%, w/v), recovered by decantation and washed with deionized water. In order to control
the process, microspheres formation was followed by optical microscopy (OM), and catechin loss
evaluated after consolidation/washing steps.
In conclusion, alginate-based microspheres loaded with catechin were efficiently produced. The
obtained microspheres have a medium particle size comprised between 73 and 341 1-Jm and
encapsulation efficiency was estimated as 87%. Overall, catechin was microencapsulated with
success, and can be incorporated in different formulations in order to apply its antioxidant
properties in cosmetic, pharmaceutical or nutraceutical areas. The work will proceed by evaluating
the protective effect of the used microencapsulation process on catechin antioxidant properties.FCT for financial support to CIMO (strategic project PEstOE/
AGR/UI0690/2011) and to LSRE (strategic project PEst-C/EQB/LA0020/2011 }. L. Barros also
thanks to FCT, POPH-QREN and FSE for her grant (SFRH/BPD/4609/2008
Utilização de extratos de Rosmarinus oficinalis L. Como ingredientes bioativos para aumentos funcionais
Introdução: A procura por parte dos consumidores de alimentos promotores de saúde é hoje uma
realidade, levando a indústria alimentar a apostar no setor dos alimentos funcionais que, para além
das suas propriedades nutricionais, conferem benefícios adicionais, nomeadamente na prevenção de
algumas doenças. Rosmarinus oficinalis L., vulgarmente conhecido por alecrim, possui vários
fitoquímicos que lhe conferem propriedades bioativas tais como atívidade antioxidante, antiinflamatória,
antimicrobiana, entre outras. Os compostos fenólicos são um exemplo importante
desses fitoquímicos bioativos.
Objetivos: Avaliar a atividade antioxidante de dois extratos de Rosmarinus oficinalis L., um aquoso e
outro hidroetanólico, e utilizar o mais ativo para incorporação em requeijões. Após desenvolvimento
do produto, confirmar as suas propriedades nutricionais e atividade antioxidante, esta avaliada para
um tempo inicial (tO) e após sete dias (t7) de armazenamento.
Materiais e Métodos: A atividade antioxidante foi avaliada através dos ensaiosefeito captador de
radicais livres (DPPH), poder redutor (PR) e inibição da peroxidação lipídica fTBARS). A composição
em macronutrientes foi avaliada de acordo com as normas oficias de análise de alimentos, tendo sido
também determinada a sua composição em lactose e ácidos gordos utilizando técnicas
cromatográficas.
Resultados e Discussão: O extrato aquoso de alecrim revelou melhores propriedades antioxidantes
comparativamente ao extraio hidroetanólico. Assim, foi utilizado para incorporação em requeijões,
tendo-se comprovado que o extrato conferiu propriedades antioxidantes aos produtos
funcionalizados (em tO e t7), uma vez que as amostras controlo (sem adição de extrato) não
apresentavam nenhuma atividade. No entanto, houve um ligeiro decréscimo dessa atividade de tO
para t7 devido a alguma degradação do extrato. Todos os requeijões aditivados com o extraio e após
análise nos dois tempos (tO e t7) mantiveram o perfil nutricional das amostras controlo.
Conclusão: A incorporação do extraio aquoso de alecrim conferiu propriedades antioxidantes ao
requeijão, mantendo o seu valor nutricional ao longo do tempo de armazenamento (7 dias a 4°C).
Contudo, para ultrapassar problemas de degradação do extrato o grupo de investigação recorreu à
técnica de microencapsulação
Application of spray-coagulation method to microencapsulate catechin having in view cosmetic, pharmaceutical or nutraceutical areas
Catechin is a polyphenolic compound of the flavonoid family and a product of the secondary
metabolism of various plants [1 ]. Antioxidant and chelating properties are attributed to catechin, as
well as to other flavonoids, due to their aromatic hydroxyl groups. The presence of these bioactive
components in diets rich in vegetables offers a protective effect in human health, including
prevention of cardiovascular disorders and certain cancers, and in the ageing process itself. When
ingested, catechin undergoes a process of metabolism that changes its structure affecting the
antioxidant properties [2]. Microencapsulation can be used to overcome this problem offering
protection by means of a cover material and enabling its controlled release over time or selectively
to an intended target [3].
In this study catechin was microencapsulated in an alginate matrix by using a spray-coagulation
technique. Briefly, a sodium alginate solution (4%, w/v) containing catechin was prepared under
stirring at ambient temperature by using a ratio catechin:alginate of 25:400 (w/w). The solution
was atomized in a Nisco Var J30 unit and microspheres consolidated upon contact with a solution
of CaCI2 (4%, w/v), recovered by decantation and washed with deionized water. In order to control
the process, microspheres formation was followed by optical microscopy (OM), and catechin loss
evaluated after consolidation/washing steps.
In conclusion, alginate-based microspheres loaded with catechin were efficiently produced. The
obtained microspheres have a medium particle size comprised between 73 and 341 1-Jm and
encapsulation efficiency was estimated as 87%. Overall, catechin was microencapsulated with
success, and can be incorporated in different formulations in order to apply its antioxidant
properties in cosmetic, pharmaceutical or nutraceutical areas. The work will proceed by evaluating
the protective effect of the used microencapsulation process on catechin antioxidant properties.FCT for financial support to CIMO (strategic project PEstOE/
AGR/UI0690/2011) and to LSRE (strategic project PEst-C/EQB/LA0020/2011 }. L. Barros also
thanks to FCT, POPH-QREN and FSE for her grant (SFRH/BPD/4609/2008
Antioxidant activity of Agaricus bisporus L. hexane and ethanol extracts obtained by Soxhlet and ultrasound-assisted extraction: the importance of the presence of ergosterol
Mushrooms are well known for their richness in bioactive molecules such as antioxidants.
Phenolic compounds, in particular phenolic acids, have been the most widely studied molecules
regarding these effects [1]. Nevertheless, other molecules present in mushrooms, such as
ergosterol, can also display bioactive properties [2]. Although being this high-value molecule
more associated with hypocholesterolemic, antimicrobial and anti-inflammatory effects [2], it is
also relevant to screen other bioactivities, such as antioxidant activity, either of the pure
molecule or of mycosterols' rich extracts containing it. Agaricus bisporus L. is the most
consumed mushroom worldwide, being ergosterol the most abundant mycosterol in its sterol
fraction (represents almost 90%) [3]. Herein, A. bisporus ethanol and hexane extracts were
prepared by Soxhlet and ultrasound-assisted extraction (amplitude: 75%;sonication time: 15
min), and further evaluated for their antioxidant activity. The in vitro assays used were: i) 2, 2-
diphenyl-1-picrylhydrazyl radical (DPPH) assay, to evaluate the scavenging activity; and ii)
ferricyanide Prussian blue assay, to evaluate the reducing power. The obtained extracts were
characterized in terms of ergosterol content by HPLC-UV. The antioxidant activity of pure
ergosterol was also assessed. The extracts obtained by Soxhlet showed higher antioxidant
activity than the ones obtained by ultrassonication, which is in agreement with the higher leveis
of ergosterol found in the flrst extracts (677 and 186 mg/100 g dw for ethanol and hexane
extracts, respectively). Ethanol extracts revealed higher antioxidant activity than the hexane
exfracts, which is also in agreement with the higher ergosterol content found in both samples
(677 and 672 mg/100 g dw for Soxhlet and ultrassonication extracts, respectively). The pure
ergosterol also showed antioxidant activity (e. g., DPPH ECso value = 0.46 mg/mL). Overall, the
ethanol extract obtained by Soxhlet gave the highest DPPH scavenging activity (EC5o = 2.2
mg/mL) and reducing power (ECsa = 0.8 mg/mL), while the hexane extract obtained by
ultrassonication revealed the lowest DPPH scavenging activity (ECso = 16.7 mg/mL) and
reducing power (EC5o= 2.2 mg/mL)
Phenolic profile and antioxidant activity of Coleostephus myconis (L.) Rchb.f.: an underexploited and highly disseminated species
Coleostephus myconis (L.) Rchb.f. (Asteraceae) is a species with ruderal growth and persistence in abandoned soils, being characterized for its plentiful yellow flowering between March and August. Despite its botanical relevance, C. myconis had never been studied neither for its antioxidant activity, nor individual phenolic compounds. Herein, the antioxidant activity of different botanical parts: stems and leaves (green parts), floral buds, flowers in anthesis and senescent flowers, was studied in selected extracts (ethanol, ethanol:water 1:1 and water) through different chemical and biochemical assays. In addition, the phenolic profiles of the hydroethanolic extracts of each botanical part were also characterized by liquid chromatography with dioade array detection and electrospray ionization tandem mass spectrometry (LC-DAD-ESI/MSn). The antioxidant activity was significantly modulated by the extract type, with the hydroethanolic extracts showing the highest antioxidant activity, especially those obtained from the senescent flowers and floral buds. The phenolic profiles were the same for all flowering stages (with quantitative differences), but that characterized in the green parts was quite different. Floral buds gave the highest contents in phenolic compounds, mainly due to the contribution of 3,5-O-dicaffeoylquinic acid and myricetin-O-methyl-hexoside. Overall, C. myconis showed an interesting potential to be included in different industrial applications.The authors are grateful to Foundation for Science and Technology (FCT, Portugal) for financial support to CIMO (PEst-OE/AGR/UI0690/2014), REQUIMTE (PEst-C/EQB/LA0006/2014), J.C.M. Barreira (SFRH/BPD/72802/2010) and L. Barros SFRH/BPD/107855/2015)
Mushroom ethanolic extracts as cosmeceuticals ingredients: Safety and ex vivo skin permeation studies
Mushrooms are important sources of natural bioactive compounds that are increasingly used as cosmeceutical
ingredients. In this context, ethanolic extracts were prepared from Ganoderma lucidum and Pleurotus ostreatus and
tested by incorporation into base cosmetic creams. In vitro safety evaluation of the extracts and cosmetic formulations
prepared therefore was carried out using the MTT and LDH assays in keratinocyte (HaCaT) and
fibroblast (HFF-1) cell lines. Moreover, they were submitted to ex vivo skin permeation studies using a Franz
diffusion apparatus with pig ear skin as permeation membrane. The results showed the absence of toxicity for
keratinocytes and fibroblasts in a concentration dependent manner, which is indicative of the safety of these
extracts for cosmeceutical ingredients purposes. Protocatechuic and syringic acids were the only compounds
permeating from G. lucidum extract in the first 8 h of study, no penetration was observed for phenolic acids found
in P. ostreatus extract and formulation. These results pointed out for the suitability of using mushroom extracts as
skin care ingredients and may contribute for the valorisation of wastes generated by the mushroom processing
industry, which can serve as raw-materials for the obtainment of the extracts.The authors are grateful to the Foundation for Science and
Technology and FEDER under Programme PT2020 for financial support
to CIMO (UID/AGR/00690/2019) and Associate Laboratory LSRE-LCM
(UID/EQU/50020/2019) funded by national funds through FCT/
MCTES (PIDDAC). This work is funded by the European Agricultural
Fund for Rural Development (EAFRD), through the Rural Development
Program (PDR2020), within the scope of Project MicoCoating
(PDR2020-101-031472). Francisca Rodrigues is thankful for her
postdoc research grant from the project Operação NORTE-01-0145-
FEDER- 000011. This work received financial support from the
European Union (FEDER funds through COMPETE), under the
Partnership Agreement PT 2020, and National Funds (FCT, Foundation
for Science and Technology) through project LAQV/UID/QUI/50006/
2013 and NORTE-07-0124-FEDER-000069 – Food Science.info:eu-repo/semantics/publishedVersio
Utilização de extrato de alecrim livre e microencapsulado como ingrediente bioativo para o desenvolvimento de alimentos funcionais
Atualmente tem-se acentuado a procura de alimentos com características funcionais para além das suas propriedades nutricionais, permitindo a obtenção de benefícios para a saúde incluindo a prevenção de doenças. Neste contexto, o alecrim (Rosmarinus officinalis L.) utilizado desde tempos ancestrais como erva aromática e medicinal, é uma importante e diversificada fonte de compostos bioativos responsáveis por diferentes propriedades, tais como antioxidantes, antimicrobianas e anti-inflamatórias[1]. Assim, o alecrim apresenta grande potencial como fonte de ingredientes bioativos para alimentos conferindo outras bioatividades ao produto final. No entanto, o uso de extratos de plantas em bases alimentares pode apresentar limitações devido à sua instabilidade mediante diversos fatores como pH, humidade, condições de processamento e armazenamento do alimento, que conduz a uma diminuição das suas propriedades biológicas[2]. A microencapsulação surge como uma alternativa para ultrapassar esta problemática
Chitosan as an antimicrobial agent for footwear leather components
In the footwear industry, microorganisms’ growth can pose problems of material deterioration with associated unpleasant smell and generate possible infections in susceptible individuals. Generally, footwear presents high relative humidity conditions that enable the growth of bacteria and fungi. Additionally, leather itself and some tannery agents such as oils and greases, provide a substrate where microorganisms can grow. In the foot, microtraumas caused by ingrown nails, abrasions and lacerations can allow microbial invasion through epidermis, resulting in skin infection.
In this work, the applicability of chitosan functional coatings to leather was tested, with the purpose to develop new base materials to produce footwear components. The leather treated with chitosan was then studied for its antibacterial properties against 3 different bacteria.COMPETE, QREN and EU (project QREN-ADI-1585-ADVANCEDSHOE)
Rosemary extracts in functional foods: extraction, chemical characterization and incorporation of free and microencapsulated forms in cottage cheese
Consumers search for food with functional characteristics beyond its nutritional properties. Thus, the concept of functional food has become a hot topic, allowing us to obtain additional health benefits, including disease prevention. In this context, plants are recognized as sources of a wide range of bioactives, including phenolic compounds. Herein, rosemary aqueous extract was used as a functional ingredient for cottage cheese, after proving that it possesses both higher content of phenolic compounds and antioxidant activity, comparatively with the corresponding hydroethanolic extract. However, a decrease of bioactivity was observed for the cheese samples enriched with the extracts in free form after seven days under storage. Therefore, in order to preserve the antioxidant activity, the rosemary aqueous extract was efficiently microencapsulated by using an atomization/coagulation technique. Overall, the introduction of both free and microencapsulated extracts provided bioactivity that was better preserved with microencapsulated extracts without changing the nutritional value of cottage cheese.FCT for financial support to CIMO (Project PEst-OE/AGR/UI0690/2014). FCT/MEC and FEDER under Program PT2020 for financial support to LSRE (Project UID/EQU/50020/2013). QREN, ON2 and FEDER (NORTE-07-0124-FEDER-000014) and PRODER (Project nº 46577- PlantLact). The GIP-USAL to the Spanish Government through the Consolider-Ingenio 2010 Programme (FUN–C-FOOD, CSD2007-00063). L. Barros and C. Caleja thank FCT, POPH-QREN and FSE for their contracts (“Programa Compromisso com Ciência-2008” and SFRH/BD/93007/2013, respectively). The authors also thank Cantinho das Aromáticas Lda., for providing rosemary samples, and to Queijos Casa Matias, for the preparation of the cottage cheese samples
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