Percorrer por autor "Demczuk Junior, Bogdan"
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- Antiangiogenic potential of yogurts added with extracts rich in apigenin derivativesPublication . Ribeiro, Andreia; Oliveira, Franciely dos Santos de; Calhelha, Ricardo C.; Demczuk Junior, Bogdan; Barreiro, M.F.; Ferreira, Isabel C.F.R.Angiogenesis is a biological process through which there is the formation of new blood vessels from preexisting ones [I]. However, in pathological cases, the abnormal growth of new blood vessels promotes the development of various diseases including cancer [2) through the production of atypically large amounts of angiogenesis factors, e.g. the vascular endothelial growth factor (VEGF) [3]. The plant secondary metabolites have been the subject of several studies to evaluate their benefits to human health. In particular, the phenolic compounds have high potential for use in the food industry, including the development of functional foods. Among these, apigenin has been associated with chemopreventive effects related to cancer [4]. In fact, chemoprevention is a present-day concept and contemplates the use of medicines, biological compounds or nutrients as an intervention strategy of cancer prevention. In this work, an Arenaria montana L hydroethanolic extract was prepared and after characterization by HPLC-DAD-ESI/MS showed to be rich in apigenin derivatives. Furthermore, it exhibited ability to inhibit the phosphorylation of VEGFR-2 (vascular endothelium growth factor receptor) through an enzymatic assay. However, for the major protection of bioactive compounds, the extract was microencapsulated by an atomization/coagulation technique with alginate as the matrix material. Posteriorly, the hydroethanolic extract, in free and microencapsulated forms, was incorporated in yogurts in order to develop a novel chemopreventer food in relation to the angiogenesis process. The functionalized yogurts with A. montana extracts (free and microencapsulated) showed a nutritional value similar to the used control (yogurt without extract); however, the samples enriched with extracts revealed added-value regarding the VEGFR-2 phosphorylation inhibition ability. This effect was more effectively preserved over time in the samples functionalized with the protected extract. Overall, this work contributes to the valorization of plants rich in flavonoids, exploring its antiangiogenic potential with VEGFR-2 as target. Moreover, the atomization/coagulation technique allowed the production of viable microspheres enriched with the plant extract. The microspheres were effectively incorporated into yogurts, protecting the extract thus envisaging the development of novel functional foods with chemopreventive effects.
- Evaluation of Arenaria montana L. hydroethanolic extract as a chemopreventive food ingredient: A case study focusing a dairy product (yogurt)Publication . Oliveira, Franciely dos Santos de; Ribeiro, Andreia; Barros, Lillian; Calhelha, Ricardo C.; Barreira, João C.M.; Demczuk Junior, Bogdan; Abreu, Rui M.V.; Barreiro, M.F.; Ferreira, Isabel C.F.R.Natural ingredients are valuable options to be exploited in the design of innovative food formulations with health benefits. Therefore, it was evaluated the potential use of Arenaria montana L. hydroethanolic extract (rich in apigenin derivatives) as a chemopreventive agent in functional foods. Apigenin is recognized as inhibiting VEGFR-2, which is the key receptor involved in angiogenesis. The obtained extract was also able to inhibit the VEGFR-2 phosphorylation through an enzymatic assay (IC 50 = ~63 µg/mL). Thereafter, free and microencapsulated forms were incorporated in yogurt. The obtained products maintained the nutritional value along the tested 3 days of storage, as also free sugars and fatty acids profiles, in comparison with the control samples. Nevertheless, the VEGFR-2 phosphorylation inhibition was not exhibited as intended. Even this behavior for the microencapsulated forms can be attributed to the protecting effect of the alginate matrix, further studies are required in order to better understand the shown performance.
- Microencapsulation of plant extracts rich in apigenin to be used as chemopreventive agents in functional foodsPublication . Oliveira, Franciely dos Santos de; Calhelha, Ricardo C.; Fernandes, Isabel P.; Demczuk Junior, Bogdan; Ferreira, Isabel C.F.R.; Barreiro, M.F.Angiogenesis is the process by which new blood vessels are formed from pre-existing vasculature, being a key process that leads to tumor development. Excessive angiogenesis occurs when diseased cells produce abnormally large amounts of angiogenesis factors (e.g. vascular endothelial growth factor (VEGF)) [1]. Some studies recognize phenolic compounds as chemopreventive agents; flavonoids seem to suppress the growth of tumor cells modifying the cell cycle and inducing apoptosis in several tumor cell lines [2]. Among them, apigenin derivatives have been recognized as having antiangiogenic effects on tumor cells being this related to a decrease in VEGF expression or to a VEGFR inhibition [3]. According to Ferreira et al. previous research, Arenaria montana L. is rich in apigenin derivatives [4]. Therefore, this plant source is ideal to prepare apigenin rich extracts to be used as chemoprevent i ve agents in functional foods. However, bioactive compounds are generally recognized as presenting problems of instability, which can weaken their bioavailability and potential benefits. Therefore, the use of microencapsulation is studied here as a way to confer protection and increasing the efficacy of functional foods incorporating these extracts [5]. In this work, a hydroethanolic extract prepared from A. montana was evaluated for its in vitro antiangiogenic effects, being further microencapsulated to be used as chemopreventive agent in functional yogurts.
- Pickering emulsions stabilized with curcumin-based solid dispersion particles as mayonnaise-like food sauce alternativesPublication . Ghirro, Larissa Camargo; Rezende, Stephany; Ribeiro, Andreia; Rodrigues, Nuno; Carocho, Márcio; Pereira, J.A.; Barros, Lillian; Demczuk Junior, Bogdan; Barreiro, M.F.; Santamaria-Echart, ArantzazuPickering emulsions, which are emulsions stabilized by colloidal particles, are being increasingly positioned as novel strategies to develop innovative food product solutions. In this context, the present work aims to develop Pickering emulsions stabilized by natural-based curcuminloaded particles produced by the solid dispersion technique as promising mayonnaise-like food sauce alternatives. Two particle formulations (KC1 and KC2) were produced using k-carrageenan as the matrix material and different curcumin contents, then employed in the preparation of three Pickering emulsion formulations comprising different oil fractions (') and particle concentrations (KC1 ' 0.4 (4.7%), KC2 ' 0.4 (4.7%) and KC2 ' 0.6 (4.0%)). The creaming index tests accompanied by the optical microscopy analysis evidenced the good stability of the developed products for the tested period of 28 days. The final products were tested concerning color attributes, pH, oxidative stability, textural, and nutritional composition, and compared with two commercial mayonnaises (traditional and light products). Overall, the produced emulsions were characterized by a bright yellow color (an appealing attribute for consumers), an acidic pH (similar to mayonnaise), and a considerably improved oxidative stability, implying a foreseeable longer shelf life. The sauce KC1 ' 0.4 (4.7%) showed a similar texture to the light commercial mayonnaise, being a promising alternative to conventional sauces, holding a low-fat content and potentially added benefits due to the curcumin and virgin olive oil intrinsic properties.
- Potencial anti-angiogénico de iogurtes com extratos ricos em derivados de apigeninaPublication . Oliveira, Franciely dos Santos de; Ribeiro, Andreia; Calhelha, Ricardo C.; Demczuk Junior, Bogdan; Barreiro, M.F.; Ferreira, Isabel C.F.R.Os metabolitos secundários das plantas têm sido alvo de diversos estudos para avaliação dos benefícios para a saúde humana. Mais concretamente, os compostos fenólicos apresentam elevado potencial de utilização na indústria alimentar, nomeadamente no desenvolvimento de alimentos funcionais. Entre estes, a apigenina tem sido associada a efeitos quimiopreventivos relacionados com o cancro. De facto, a quimioprevenção é um conceito atual e contempla a utilização de medicamentos, compostos biológicos ou nutrientes como estratégia de intervenção na prevenção do cancro. Neste trabalho, preparou-se um extrato a partir de Arenaria montana L. utilizando etanol: água (80:20, v/v) como solvente de extração que, após caracterização por HPLCDAD- ESI/MS mostrou ser rico em derivados de apigenina e possuir um elevado potencial anti-angiogénico demonstrado pela capacidade de inibição da fosforilação do VEGFR-2 (vascular endotelium growth fator receptor). Com o intuito de proteger o potencial bioativo do extrato recorreu-se à sua microencapsulação com alginato através da técnica atomização/coagulação. Posteriormente, utilizaram-se extratos hidroetanólicos, na sua forma livre e microencapsulada, para funcionalizar uma matriz alimentar- iogurte- com o intuito de desenvolver alimentos quimiopreventivos em relação ao processo da angiogénese. Os iogurtes funcionalizados com extrato de A. montana (livre e encapsulado) mostraram um valor nutricional similar ao controlo (iogurte não enriquecido), mas um aumento da capacidade de inibição da fosforilação do VEGFR-2. Este efeito foi mais preservado ao longo do tempo nas amostras funcionalizadas com o extrato protegido. Em suma, este trabalho contribui para a valorização de plantas ricas em flavonoides, explorando o seu potencial anti-angiogénico pela interação com o VEGFR-2.