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- Unveiling the impact of thermal water in German chamomile infusions: effects on phenolic compounds, antimicrobial and antioxidant propertiesPublication . Silveira, Tayse F. F. da; Echegaray, Noemí; Guimarães, Rafaela; Lemos, André; Pires, Tânia C.S.P.; Ferreira, Isabel C.F.R.; Alves, Maria José; Barros, LillianGerman chamomile (GC) and thermal water (TW) are widely known for their biological properties. This study explored whether combining GC with TW could promote an improvement in the bioactivities of GC infusions compared to using drinking water (DW). DW was tested at 100 ◦C (GC-100DW) and TW at both 100 ◦C (GC-100TW) and 60 ◦C (GC-60TW). The use of TW for preparing infusions was associated with the reduction of the number and concentration of extracted phenolic compounds, with GC-60TW showing the lowest levels. It was also associated with a decrease in the antioxidant activity of the samples, as indicated by lower ORAC values and higher EC50 levels for TBARS. However, GC infusions prepared with TW, particularly GC-100TW, exhibited higher antibacterial and antifungal activities. These findings suggest that while TW’s high mineral content affected phenolic extraction and antioxidant potential, it was associated with enhanced antimicrobial activity, partially confirming our hypothesis.
- Exploring the potential of underrated yet versatile crop Lunaria annua L.: New insights into honesty plantPublication . Petrović, Jovana; Almeida, Daiana; Fernandes, Ângela; Stojković, Dejan; Robajac, Dragana; Silveira, Tayse F. F. da; Barros, LillianLunaria annua is an underexplored crop with promising potential for use in various industries: food, oil etc. It grows rapidly, has low maintenance and high resistance to pathogens, which makes it a promising crop for sustainable cultivation. Herein, we investigated nutritional value, phenolic profile, and bioactive properties of L. annua seeds collected in the wild. The results we obtained indicate that seeds of L. annua have high energy value (406.6 kcal/100 g dw), with high share of carbohydrates (65.2 g/100 g dw), followed by proteins (26.47 g/100 g dw) and fat (4.46 g/100 g dw). Free sugar analysis showed presence of fructose, glucose and sucrose (0.77 g, 0.189 g and 3.85 g/100 g dw, respectively). Oxalic and malic acid were quantified <1.0 g/100 g dw and fumaric acid only in trace. Monounsaturated fatty acids were predominant over polyunsaturated and saturated fatty acids (erucic, nervonic and oleic acid were dominant). The content of flavonoid compounds was several times higher than the content of phenolic acids (58.5 vs 9.4 mg/g). Methanolic extract showed better antioxidant potential than dichloromethane extract (EC50 = 0.32 vs. 1.25 mg/mL, in TBARS test). The antibacterial activity ranged from 0.50 to 2.00 mg/mL, with E. coli showing the highest susceptibility to the methanolic extract (MIC: 0.25 mg/mL, MBC: 0.50 mg/mL). The other tested microorganisms showed quite uniform susceptibility to the extracts, but better than the positive controls E211 and E224. The tested samples demonstrated encouraging antifungal/anticandidal properties, and no cytotoxic effects onto spontaneously immortalized keratinocytes cell line HaCaT, indicating its safe application in terms of dermal exposure. Overall, our results indicate that L. annua seeds may be considered as source of compounds used in food and pharmaceutical industry and a candidate for functional ingredient that provides additional health benefits beyond basic nutritional requirements.
- Development of bioactive edible coatings enriched with extracts of celery and banana inflorescence for the preservation of persimmonsPublication . Oliveira, Izamara; Silveira, Tayse F. F. da; Garcia, Vitor Augusto dos Santos; Veiga-Santos, Pricila; Lima, Giuseppina Pace Pereira; Lima, Laíres; Santos-Buelga, Celestino; Barros, Lillian; Heleno, Sandrina A.; Carocho, MárcioEdible coatings enriched with bioactive compounds have emerged as promising alternatives to synthetic preservatives, aligning with sustainability goals and offering solutions for the conservation of perishable fruits. This study aimed to develop and evaluate the efficacy of edible coatings formulated with celery (Apium graveolens L.) and banana inflorescence (Musa acuminata var. “Dwarf Cavendish”) extracts, known for their antioxidant properties, in extending the shelf life of persimmons (Diospyros kaki L. var. Giombo). The extraction of phenolic compounds and flavonoids from both botanical sources was optimized using Response Surface Methodology (RSM), and the extracts were incorporated into agar-based edible coatings. Physicochemical parameters such as color (L*, a*, b*), pH, total phenolics, antioxidant activity (DPPH, FRAP), and total carotenoids were analyzed throughout storage at both refrigerated and room temperatures. The coatings exhibited moderate but significant effects on persimmon preservation, particularly in maintaining lightness (L*). Celery extract-based coatings showed 61.0 ± 2.1 at day 10 under refrigeration, compared to 55.0 ± 3.4 in banana inflorescence formulations. Over the storage period, total phenolics in coated samples degraded at a slower rate (0.3 ± 0.2 mg GAE/g in refrigerated conditions), while the antioxidant activity remained higher (DPPH EC50 = 80 ± 12 μg/mL for celery coatings at day 10). Color degradation was evident across all treatments, but coatings with celery extract were more effective in reducing changes in b (yellow-blue coordinate)**, maintaining a b value of 51 ± 6 at day 10, whereas uncoated samples decreased to 47 ± 10. These findings suggest that while the tested coatings provide some level of preservation, further optimization is required to enhance their efficacy, particularly in improving barrier properties and bioactive compound stability. Future research should focus on refining formulations by incorporating additional stabilizers and optimizing temperature conditions to enhance the preservation and safety aspects of coated fruits, ensuring their viability for commercial applications in the food industry.
- Phytochemical diversity and biological activities of Hypericum japonicum and Hypericum sampsonii: potential for natural product-based food applicationsPublication . Barciela, Paula; Rodrigues, Daniele B.; Perez-Vazquez, Ana; Silveira, Tayse F. F. da; Pires, Tânia C.S.P.; Mandim, Filipa; Carpena, Maria; Pereira, Carla; Ferreira, Isabel C.F.R.; Barros, Lillian; Prieto, Miguel A.This study characterizes two species of the genus Hypericum to envisage their applicability as effective and versatile functional foods, dietary supplements, and food preservatives. A wide phenolic composition was found in both extracts, highlighting flanovoids for H. japonicum and xanthones for H. sampsonii. Moreover, anthocya- nins were analyzed for the first time in the latter plant. Antioxidant capacity was highlighted by oxidative he- molysis inhibition assay (OxHLIA), where H. japonicum was more effective (lower EC50) than antioxidant Trolox (16.3 < 21.8 μg/mL). H. sampsonii extract inhibited lipid peroxidation in the thiobarbituric acid reactive sub- stances (TBARS) method (EC50 = 17.05 μg/mL) compared to Trolox (EC50 = 5.8 μg/mL). H. japonicum anti- bacterial activity showed a minimum inhibitory concentration (MIC) of 0.007 mg/mL, even lower than the control. These results indicate the bioactive potential of both extracts, as well as the importance of evaluating the food-related bioactive components of medicinal plants and the mechanisms involved in their bioactivities.
- Bioactivities of Waste Cork and Phloem Fractions of Quercus cerris BarkPublication . Şen, Ali Umut; Almeida, Daiana; Silveira, Tayse F. F. da; Pires, Tânia C.S.P.; Añibarro-Ortega, Mikel; Mandim, Filipa; Barros, Lillian; Ferreira, Isabel C.F.R.; Pereira, Helena; Fernandes, ÂngelaRecently, more and more researchers have begun to consider using waste bark fractions to produce value-added biochemicals and materials, as well as for energy production. Extraction is often the first operation in biomass biorefineries. Here we obtained hydroethanolic extracts from waste cork and phloem fractions of Quercus cerris bark and analyzed them to determine their antioxidant, antimicrobial, and nitric oxide (NO) production inhibition properties and their hepatotoxicity. The antioxidant properties were investigated by ex vivo TBARSs as well as OxHLIA antioxidant assays, the antibacterial properties against Gram-positive and Gram-negative bacteria isolated from food and clinical sources, and antifungal properties against Aspergillus brasiliensis and A. fumigatus. The NO production inhibition activity was assessed in a lipopolysaccharide (LPS)-stimulated murine macrophage (RAW 264.7) cell line, and antiproliferative activities were determined against five different cell lines, including lung (NCI-H460), gastric (AGS), breast (MCF7), and colon (CaCo2) tumor cell lines, as well as a non-tumor cell line (PLP2). The hydroethanolic maceration of waste cork and phloem yielded 4.4% and 2.4% extracts, respectively. Gallic acid glucosides, phenolic acids, and ellagic acid were identified in both extracts. The waste cork and phloem extracts showed antioxidant, antimicrobial, antifungal, and antiproliferative properties but also showed hepatotoxicity in the case of waste cork. Both bark fractions varied in terms of their bioactivity, with waste cork extracts showing, in general, higher bioactivity than phloem extracts.
- A green method for anthocyanin extraction from Clitoria ternatea flowers cultivated in southern Brazil: characterization, in vivo toxicity, and biological activityPublication . Gonçalves, Glória C.P.; Rosas, Alexandra L.G.; Sousa, Rafael C. de; Vieira, Thaís R.R.; Sousa, Thamyres C. de Albuquerque; Ramires, Tassiana; Silveira, Tayse F. F. da; Barros, Lillian; Silva, Wladimir Padilha da; Dias, Álvaro R.G.; Zavareze, Elessandra da Rosa; Meinhart, Adriana DillenburgThis study aimed to develop a green method to obtain an anthocyanin-rich edible extract of Clitoria ternatea flowers grown in southern Brazil. The extract was characterized by UHPLC-MSn and analyzed for toxicological potential in an in vivo model, total phenolic content, and biological activities. By using a 23 multivariate design to study the effects of temperature, acidified solvent, and time on the total anthocyanin content (487.25 mg/g), total phenolic content (2242.47 mgGAE/g), it was possible to determine the optimal point (45 ◦C, 16 min, and 22.5 mL extraction solution). Thirteen anthocyanins and nine non-anthocyanins were quantified. In vivo toxicity assay using Galleria mellonella showed a safe concentration when administered up to 2.2 g of extract per body kg. The extract showed antioxidant activity and antibacterial action against food pathogens, the method proved to have a low environmental impact, in addition to producing an extract with potential for application in food.
- Development and characterisation of gluten‐free fresh pasta using teff, rice, and buckwheat flours enhanced with thermal waters: a mixture design approachPublication . Silveira, Tayse F. F. da; Hasni, Jihene; Portelada, Nathalie; Fernandes, Filipa Alexandra; Rodrigues, Paula; Lemos, André; Ferreira, Isabel C.F.R.; Alves, Maria José; Barros, Lillian; Heleno, Sandrina A.To meet the demand for gluten-free (GF) products, this study developed artisanal fresh pasta using teff, rice, and buckwheat flours, enhanced with mineral-rich thermal waters (TW). A mixture design approach optimised flour proportions to balance texture, cooking time, water absorption, and cooking loss, along with functional properties such as total phenolic compounds (TPC) and antioxidant activity. Two promising formulations were identified: 36.3 g buckwheat, 9.35 g rice, and 9.35 g teff; and 27.5 g teff and 27.5 g buckwheat. These formulations, with and without TW, were evaluated for chemical, technological, microbiological, and functional attributes. The pasta had satisfactory technological properties, macronutrient levels comparable to standard pasta, and was rich in phenolic compounds with antioxidant activity. Ca, Zn, Fe, K, and Mn were predominant, although TW incorporation did not significantly affect their levels in the samples. All formulations showed microbiological stability for at least 3 days at 4 °C.
- Exploring the Bioactive Properties of Hydroethanolic Cork Extracts of Quercus cerris and Quercus suberPublication . Sen, Umut; Almeida, Daiana; Silveira, Tayse F. F. da; Pires, Tânia C.S.P.; Añibarro-Ortega, Mikel; Mandim, Filipa; Barros, Lillian; Ferreira, Isabel C.F.R.; Pereira, Helena; Fernandes, ÂngelaThe bioactive properties of underutilized corks such as Quercus cerris cork and planted Quercus suber cork in the Eastern Mediterranean are not well-known but are crucial in developing lignocellulosic biorefineries. To assess their biological potential, hydroethanolic cork extracts of Quercus cerris and Quercus suber were analyzed for phenolic composition, antioxidant, antiproliferative, antimicrobial activities, and hepatoxicity, as well as NO-production inhibition. Here, we show that a mild hydroethanolic extraction of Q. cerris and Q. suber corks yielded 3% phenolic extracts. The phenolic composition was similar in both cork extracts, with phenolic acids and ellagitannins as the primary compounds. The bioactivity of hydroethanolic cork extracts from Q. cerris surpassed that of Q. suber and showed effectiveness against all cancer cell lines tested. This first comprehensive study on the bioactivities of different corks involves detailed characterizations of phenolic compounds of cork extracts using UPLC-DAD-ESI/MSn, evaluations of the antioxidant properties with TBARS and OxHLIA methods, evaluation of antiproliferative activity against gastric (AGS), lung (NCI-H460), colon (CaCo2), and breast cancer (MCF7) cell lines, as well as evaluations of hepatotoxicity and NO-production inhibition. The findings from this study will help bolster the potential of using underutilized cork-rich barks as a valuable resource in bark-based biorefineries.
- Yerba mate as an inexpensive source of analytical standards of chlorogenic acid isomers: an optimization studyPublication . Meinhart, Adriana Dillenburg; Silveira, Tayse F. F. da; Godoy, Helena TeixeiraChlorogenic acid isomers have been increasingly studied because of their beneficial biological effects in humans. However, their commercial analytical standards are high cost, a fact that limits research. Yerba mate (Ilex paraguariensis) is a lowcost, natural plant matrix with marked contents of chlorogenic acids, but its potential as a source of analytical standards of chlogenic acids has never been investigated. Thus, this study aimed to optimize a method to extract, isolate, and purify analytical standards of six chlorogenic acids (3-caffeoylquinic, 4-caffeoylquinic, 5-caffeoylquinic, 3,4-dicaffeoylquinic, 3,5-dicaffeoylquinic, and 4,5-dicaffeoylquinic) from yerba mate (Ilex paraguariensis) using semi-preparative high-performance liquid chromatography. For this, sequential statistical multivariate approaches (central composite designs) were utilized. Using the optimized extraction conditions (5 mL of ethanol:water 26:74 v/v, stirring for 30 min at 60 °C), 1000 g of yerba mate gave a concentrated extract totalizing 21.57 g of chlorogenic acid isomers. We established optimized chromatographic conditions to obtain analytical standards of each compound individually, as well as to produce a mix containing all the compounds, with high yields and purities above 97%. Thus, the optimized conditions to obtain the standards have an excellent yield, employed a natural low-cost matrix, and used simple and automated processes with potential to produce in laboratory and industrial scale. These results show the potential of yerba mate as a novel source of standards of chlorogenic acids, and provide an effective method to produce them in laboratories worldwide, which may contribute to advance the research on these compounds.
- HPLC-DAD-(ESI)-MS/MS analysis as the first step to metabolic fingerprinting of medicinal herbs: the case of underexploited Euphorbia speciesPublication . Silveira, Tayse F. F. da; Rodrigues, Daniele Bobrowski; Vazquez, A.P.; Alvarez, Paula Barciela; Carpena Rodríguez, María; Simal-Gandara, Jesus; Prieto Lage, Miguel A.; Barros, LillianThe genus Euphorbia comprises more than 2,000 species widely distributed in Asia, Africa and Latin America. They have been extensively used in folk medicine to treat disorders such as abdominal pain, skin diseases, tumors, wart, among others¹. Although the well-recognized ethnopharmacological relevance of Euphorbia species, most of them have not been studied yet, such as Euphorbia hirta and Euphorbia jokinii. In this context, screening the bioactive molecules potentially responsible for the observed medicinal effects is an initial, but key step for discovering novel active compounds and understanding the mechanisms of action underlying their biological activities. Thus, this study aimed at determining the phenolic compounds composition of E. Hirta and E. jokinii. Both plants were freezedried, milled, and extracted with ethanol:water (60:40 v/v) for 3 hours at 45 °C. After centrifugation, the extracts were freeze-dried, re-suspended in ethanol:water (20:80 v/v), filtered and injected into the HPLC-DAD-(ESI)-MS/MS system. The phenolic profile of E. Hirta and E. Jokinii revealed mainly the presence of flavonoids and galloyl derivatives. Thirty-two compounds were tentatively identified in E. Hirta and twenty-two in E. Jokinii. Quercetin 3-O-rhamnoside was the major compound in both species, with E. Hirta showing the highest content (10.5 mg/g vs 8.2 mg/g extract). Our results indicate that E. Hirta and E. Jokinii, yet underexploited Euphorbia species, are interesting sources of flavonoids. Further studies should evaluate the relationship between these compounds and the biological activities of these plants, as well as establish possible related mechanisms of action.
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