A carregar...
6 resultados
Resultados da pesquisa
A mostrar 1 - 6 de 6
- Application of encapsulated tomato by-product extract as a colorant in mascarponePublication . Molina, Adriana K.; Leichtweis, Maria Gabriela; Machado, Manuela; Silva, Sara; Pintado, Manuela; Barreira, João C.M.; Dias, Maria Inês; Prieto Lage, Miguel A.; Barros, Lillian; Pereira, CarlaAgricultural by-products, often underutilized, represent a significant opportunity to obtain sustainable value-added products to develop new functional foods. In this context, the (typically discarded) aerial parts of tomato plants (Solanum lycopersicum L. var. cerasiforme), were studied as new sources of natural bioactive compounds, focusing the extraction and encapsulation (using spray drying with maltodextrin as the encapsulant) of chlorophylls. The encapsulated natural colorant was subsequently incorporated into mascarpone cheese to assess its stability and effect on nutritional and antioxidant properties. The obtained extracts were mainly characterized by high concentrations of bioactive compounds, particularly quercetin-3-O-deoxyhexoside (14.4 ± 0.3 mg/g). The colorant imparted a greener hue to the mascarpone (a* –6.0 ± 0.05 vs. –1.7 ± 0.05 in control, p < 0.001) and maintained antioxidant activity (OxHLIA EC₅₀ = 1440 ± 72 to 1166 ± 66 μg/mL, p = 0.030) without altering the nutritional profile (p > 0.05). Moreover, no cytotoxicity was observed, and the fatty acid composition remained unchanged. Accordingly, the studied encapsulated colorant might be used as a functional ingredient in other dairy products, imparting an attractive color while preserving nutritional integrity. In conclusion, the incorporation of TAPC is an effective strategy to enrich dairy products with natural pigments and bioactive compounds without compromising quality. Future research is needed to explore its application in other food matrices and assess long-term storage effects.
- A Combination of LED and Compost to Improve Spinacia oleracea L. Quality and Chemical CompositionPublication . Hernández-Lara, Alicia; Almeida, Daiana; Silveira, Tayse F. F. da; Nájera, Cinthia; Pereira, Carla; Fernandes, Ângela; Ros, Margarita; Pascual, José Antonio; Barros, LillianSpinach has a high content of nutrients, proteins, carbohydrates, and vitamins beneficial for human health, that are closely associated with the type of crop, the growing media, the temperature, and lights used for growing. Two types of light were used: white light (WL) and red light (RL), and also three different growing media: compost without additives (CB), compost with coffee additive (CC), and compost with rockrose additive (CR). Spinach grown under WL, regardless of the treatment, showed greater plant growth than that grown under RL_P. Furthermore, treatments WL_CC and WL_CR increased by 90% and 95%, respectively, compared to WL_P; similarly, treatments WL_CB, WL_CC, and WL_CR increased by 179%, 174%, and 205%, respectively, compared to the RL_P control. The protein content of spinach leaves from growing media WL_CB and WL_CC increased by 50 and 46% respectively compared to WL_P; similarly, growing media RL_CB and RL_CC increased by 82 and 57% respectively compared to RL_P. This contrasted with the carbohydrate content, which was higher in spinach grown under WL_P and RL_P. Spinach grown under WL_P and RL_P showed significantly more free sugars. On the other hand, spinach grown under WL had a higher concentration of organic acids than that grown under RL, regardless of the growing media used. The content of fatty acids, phenolic compounds, and antioxidant activities did not follow a clear pattern with respect to the type of light and growing media. Overall, compost-based substrates combined with white LED light enhanced spinach growth and nutritional quality through a synergistic effect. However, compost reduced phenolic compounds, while red LED light increased phenolic content and antioxidant activity, indicating contrasting effects on spinach quality.
- Extracts from berries of Portuguese Vitis vinifera L. varieties Vinhão and Loureiro exhibit powerful antioxidant, antihaemolytic, and cytotoxic activitiesPublication . Nipo, Maria; Simões, Luara; Noronha, Henrique; Barros, Lillian; Finimundy, Tiane C.; Pereira, Carla; Calhelha, Ricardo C.; Parpot, Pier; Ševčovičová, Andrea; Oliveira, RuiGrapes (Vitis vinifera L.) are widely consumed fruits known for their diverse bioactive compounds. Vinhão and Loureiro are the major red and white grape varieties, respectively, of the largest Portuguese wine region: Vinho Verde. Large amounts of residues are produced in wine making that potentially are rich in bioactive compounds, so this study aimed at valorizing the residues from these grape varieties for further applications. The grape extracts were obtained from the seeds and from the pulp and skin together for characterization. The phenolic composition differed across these parts, with the seeds being particularly rich in polyphenols and flavonoids. Both varieties exhibited high antioxidant activity; seed extracts stood out, showing the strongest radical scavenging ability (IC50 = 0.22 +/- 0.08 for 2,2-diphenyl-1-picrylhydrazyl and 0.004 +/- 0.001 mg mL-1 for thiobarbituric acid reactive substances assays). The Loureiro seed extract showed higher antihaemolytic properties (IC50 = 4.81 +/- 0.22 mu g mL-1) by protecting erythrocyte membranes from oxidative damage. The seed extracts displayed cytotoxic potential on tested tumor cells, particularly with the Loureiro variety. Overall, the results suggest that both varieties have high antioxidant properties, with the seed extracts showing the most promising bioactivities. Although further characterization is required in terms of bioactivity in in vivo experimental models, these findings contribute to the potential utilization of grape extracts and their waste products, providing new applications for Portuguese grape varieties in various applications, such as pharmaceuticals, cosmetics, and nutraceuticals.
- Bioactive and Phenolic Profiles in Pinus pinaster Bark: A Comparative Study of Microwave and Ultrasound Extraction MethodsPublication . Barros, Diana; Alonso-Esteban, José Ignacio; Finimundy, Tiane C.; Pereira, Carla; Vaz, Josiana A.; Pereira-Pinto, Ricardo; Fernandes, Élia; Pires, Preciosa; Santos, Joana; Barros, Lillian; Vaz-Velho, ManuelaThis study conducted a comprehensive comparison of two green extraction methods, microwave-assisted extraction (MAE) and ultrasound-assisted extraction (UAE), for recovering bioactive phenolic compounds from Pinus pinaster bark. The goal was to valorize timber industry waste and enhance the value of by-products through the development of eco-friendly processes to extract phenolic compounds from Pinus pinaster Aiton subsp. atlantica in northwest Portugal. MAE achieved significantly higher extraction yields than UAE (11.13 vs. 3.47 g extract/100 g bark) and superior total phenolic content (833 vs. 514 mg GAE/g). MAE extracts also exhibited enhanced antioxidant activity in most assays tested (DPPH, ABTS, ORAC, and OxHLIA), while both extracts effectively inhibited lipid peroxidation (TBARS) and showed activity against Gram-positive bacteria. Phenolic profile analysis revealed that MAE recovered a substantially higher amount of total phenolic compounds (230.0 mg/g) compared to UAE (86.95 mg/g), with procyanidins identified as the predominant compounds. The greater recovery of this complex procyanidin mixture by MAE is strongly associated with the enhanced bioactivities observed. Overall, this study confirms MAE as a highly efficient and sustainable technology for transforming pine bark waste into valuable antioxidant and antimicrobial extracts with potential applications in the food and pharmaceutical industries.
- Valorization of angolan native plants: Nutritional composition, phenolic profile and bioactive potential of Commelina africana, Dombeya rotundifolia and Lablab purpureus leavesPublication . Bastos, Claudete; Liberal, Ângela; Silveira, Tayse F. F. da; Ferreira, Isabel C.F.R.; Pereira, Carla; Pires, Tânia C.S.P.; Mandim, Filipa; Moldão, Margarida; Catarino, Luís; Barros, LillianCommelina africana L., Dombeya rotundifolia (Hochst.) Planch. and Lablab purpureus (L.) Sweet are wild edible plants (WEPs) native to Africa, traditionally used in rural Angolan communities. This study characterizes their nutritional, chemical, and bioactive properties, with carbohydrates and proteins predominating as macronutrients across all species. Monounsaturated and polyunsaturated fatty acids were most abundant in D. rotundifolia and C. africana. Phenolic profiling revealed that C. africana was mainly characterized by p-coumaroyl malic acid and caffeoyl shikimic acid, whereas D. rotundifolia contained majorly flavan-3-ols, including epicatechin and B-type procyanidin oligomers. In contrast, L. purpureus exhibited the highest total phenolic content overall. The hydroethanolic extract of D. rotundifolia exhibited the highest efficacy against foodborne and clinical bacteria and inhibition of cancer cell proliferation. This integrated characterization demonstrates that these underutilized WEPs offer substantial dual nutritional and bioactive value, supporting their traditional use and potential for nutraceuticals and food applications.
- Enhancing shelf life of pumpkin pulp with natural-based preservative and high pressure processingPublication . Ribeiro, Luma Rossi; Leichtweis, Maria Gabriela; Landgräber, Eva; Silva, Beatriz; Azevedo, Miguel; Pereira, Carla; Carocho, Márcio; Barros, Lillian; Schlüter, OliverFormulated pumpkin pulp fruit was incorporated with natural-based preservative (NBP) extracted from pumpkin peels (Butternut Squash), industrial mix (with and without potassium sorbate), processed by high pressure processing (HPP- 600 MPa/4 min) and stored at 5 °C for 45 days. The shelf life was evaluated by microbiological analysis (total aerobic mesophilic, Enterobacteriaceae and molds and yeasts), pH, color, texture (TPA) and oxidative stability via changes in β-carotene, γ-tocopherol, total phenolic content (TPC) and antioxidant potential (FRAP). No microbial growth was detected in any formulation throughout the 45-day storage period, likely due to the combined effects of processing, the industrial mix, and the added NBP. Samples containing NBP better preserved color and firmness and exhibited significantly higher total phenolic content compared to other formulations. In contrast, thermally treated samples showed greater changes in texture (firmness, stickiness, chewiness) and in bioactive compounds such as β-carotene, lutein, and γ-tocopherol. Overall, processing method, NBP addition, and storage time did not significantly compromise the nutritional quality of the formulations. The combination of high pressure processing and NBP demonstrated strong potential for extending shelf life, allowing a 50% reduction or complete replacement of potassium sorbate without compromising safety or quality.