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"Coelho, Marta"
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Carotenoids Diet: Digestion, Gut Microbiota Modulation, and Inflammatory Diseases
2023
Several epidemiologic studies have found that consuming fruits and vegetables lowers the risk of getting a variety of chronic illnesses, including several types of cancers, cardiovascular diseases (CVDs), and bowel diseases. Although there is still debate over the bioactive components, various secondary plant metabolites have been linked to these positive health benefits. Many of these features have recently been connected to carotenoids and their metabolites’ effects on intracellular signalling cascades, which influence gene expression and protein translation. Carotenoids are the most prevalent lipid-soluble phytochemicals in the human diet, are found in micromolar amounts in human serum, and are very susceptible to multiple oxidation and isomerisation reactions. The gastrointestinal delivery system, digestion processes, stability, and functionality of carotenoids, as well as their impact on the gut microbiota and how carotenoids may be effective modulators of oxidative stress and inflammatory pathways, are still lacking research advances. Although several pathways involved in carotenoids’ bioactivity have been identified, future studies should focus on the carotenoids’ relationships, related metabolites, and their effects on transcription factors and metabolism.
Journal Article
Anthocyanin Recovery from Grape by-Products by Combining Ohmic Heating with Food-Grade Solvents: Phenolic Composition, Antioxidant, and Antimicrobial Properties
2021
Usually, wine-making by-products are discarded, presenting a significant environmental impact. However, they can be used as a source of bioactive compounds. Moreover, consumers’ increasing demand for naturally nutritious and healthy products requires new formulations and food product improvement, together with sustainable, environmentally friendly extraction methods. Thus, this work aimed to compare ohmic heating (OH) with conventional methodology (CONV), using food-grade solvents, mainly water, compared to standard methanol extraction of anthocyanins. No significant differences were found between the CONV and OH for total phenolic compounds, which were 2.84 ± 0.037 and 3.28 ± 0.46 mg/g DW gallic acid equivalent, respectively. The same tendency was found for antioxidant capacity, where CONV and OH presented values of 2.02 ± 0.007 g/100 g and 2.34 ± 0.066 g/100 g ascorbic acid equivalent, respectively. The major anthocyanins identified were malvidin-3-O-acetylglucoside, delphinidin-3-O-glucoside, petunidine-3-O-glucoside, cyanidin-3-O-glucoside, and peonidine-3-O-glucoside. These extracts displayed antimicrobial potential against microorganisms such as Yersinia enterocolitica, Pseudomonas aeruginosa, Salmonella enteritidis, methicillin-sensitive Staphylococcus aureus, a methicillin-resistant Staph. aureus (MRSA), and Bacillus cereus. In conclusion, OH provides similar recovery yields with reduced treatment times, less energy consumption, and no need for organic solvents (green extraction routes). Thus, OH combined with water and citric acid allows a safe anthocyanin extraction from grape by-products, thus avoiding the use of toxic solvents such as methanol, and with high biological potential, including antimicrobial and antioxidant activity.
Journal Article
Natural Pigments Recovery from Food By-Products: Health Benefits towards the Food Industry
by
Rocha, Helena R.
,
Gonçalves, Ricardo
,
Magalhães, Daniela
in
Algae
,
Antioxidants
,
bioactive properties
2024
Given the health risks associated with synthetic colorants, natural pigments have emerged as a promising alternative. These renewable choices not only provide health benefits but also offer valuable technical and sensory properties to food systems. The effective application of natural colorants, however, requires the optimization of processing conditions, exploration of new sources, and development of novel formulations to ensure stability and maintain their inherent qualities. Several natural pigment sources have been explored to achieve the broad color range desired by consumers. The purpose of this review is to explore the current advances in the obtention and utilization of natural pigments derived from by-products, which possess health-enhancing properties and are extracted through environmentally friendly methods. Moreover, this review provides new insights into the extraction processes, applications, and bioactivities of different types of pigments.
Journal Article
Tomato Processing By-Products Valorisation through Ohmic Heating Approach
by
Ghalamara, Soudabeh
,
Campos, Débora
,
Coelho, Marta C.
in
Agricultural wastes
,
antioxidant activity
,
Bioactive compounds
2023
Tomato by-products from processing industries have a higher potential to be reused as a source of bioactive compounds. Reliable national data on tomato by-products and physicochemical characterisation that will inform and find effective planning on tomato waste management in Portugal is absent. To help obtain this knowledge, selected Portugal companies were recruited to obtain representative samples of by-products generation, and physicochemical composition was evaluated. Furthermore, an environmental-friendly method (the ohmic heating (OH) method, which allows the recovery of bioactive compounds in absence of hazardous reagents) was also used and compared with conventional methods to explore new safe value-added ingredients. Total antioxidant capacity and total and individual phenolic compounds were also evaluated by spectrophotometric and high-performance liquid chromatography (HPLC), respectively. Tomato processing by-products have revealed a higher potential since both collected samples from companies were rich in protein (between 16.3 to 19.4 g/100 g DW, with fibre content ranging from 57.8 to 59.0 g/100 g DW). In addition, these samples contain 17.0 g/100 g of fatty acids (mainly polyunsaturated, monounsaturated and saturated, such as linoleic, oleic, and palmitic acid, respectively). Also, they present mainly chlorogenic acid and rutin as phenolic compounds. After understanding its composition, the OH was applied to determine added-value solutions to tomato by-products. With extractions, two types of fractions were obtained, namely liquid fraction rich in phenols, free sugars, and carotenoids and a solid fraction rich in fibre bound to phenols and carotenoids. This treatment has been shown to have the ability to preserve carotenoids, such as lycopene relative to conventional methods. Nevertheless, new molecules were identified by LC-ESI-UHR-OqTOF-MS analysis, such as phene-di-hexane and N-acethyl-D-tryptophan. According to the results, the OH boosts the potential of tomato by-products and can be directly introduced into the process, contributing to the circular economy and zero by-products.
Journal Article
Bioinformatic Insights into the Carotenoids’ Role in Gut Microbiota Dynamics
by
Rodrigues, Pedro Miguel
,
Gomes, Ana M.
,
Rocha, Helena R.
in
Algae
,
Antioxidants - pharmacology
,
Bacteria - classification
2026
Background/Objectives: Carotenoids are bioactive pigments with well-established antioxidant and immunomodulatory properties, yet their impact on gut microbiota remains poorly understood from a chemical standpoint. This study explores how carotenoid structure and gastrointestinal stability shape microbial responses combining in vitro fermentation with bioinformatic analyses. Methods: Individual carotenoids (beta (β)-carotene, lutein, lycopene) and combined carotenoids, as well as algal-derived extracts were subjected to 48 h in vitro fermentation, and microbial composition and activity were assessed through sequencing and computational analysis. Results: β-carotene and lycopene promoted acid-tolerant taxa such as Escherichia-Shigella, whereas lutein, due to its higher polarity, supported more transient fluctuations. Mixtures and algal carotenoids exhibited synergistic effects, sustaining beneficial genera including Bifidobacterium and Bacteroides and promoting structured ecological trajectories. Conclusions: These findings provide a chemistry-driven perspective on how carotenoids act as modulators of microbial ecosystems, with direct implications for the formulation of carotenoid-enriched functional foods and dietary interventions.
Journal Article
Evaluation of Microbial-Fructo-Oligosaccharides Metabolism by Human Gut Microbiota Fermentation as Compared to Commercial Inulin-Derived Oligosaccharides
by
Nobre, Clarisse
,
Coelho, Elisabete
,
Coelho, Marta C.
in
Aspergillus ibericus
,
Bacteria
,
Carbohydrates
2022
The prebiotic potential of fructo-oligosaccharides (microbial-FOS) produced by a newly isolated Aspergillus ibericus, and purified by Saccharomyces cerevisiae YIL162 W, was evaluated. Their chemical structure and functionality were compared to a non-microbial commercial FOS sample. Prebiotics were fermented in vitro by fecal microbiota of five healthy volunteers. Microbial-FOS significantly stimulated the growth of Bifidobacterium probiotic strains, triggering a beneficial effect on gut microbiota composition. A higher amount of total short-chain fatty acids (SCFA) was produced by microbial-FOS fermentation as compared to commercial-FOS, particularly propionate and butyrate. Inulin neoseries oligosaccharides, with a degree of polymerization (DP) up to 5 (e.g., neokestose and neonystose), were identified only in the microbial-FOS mixture. More than 10% of the microbial-oligosaccharides showed a DP higher than 5. Differences identified in the structures of the FOS samples may explain their different functionalities. Results indicate that microbial-FOS exhibit promising potential as nutraceutical ingredients for positive gut microbiota modulation.
Journal Article
Modulation of the Gut Microbiota by Tomato Flours Obtained after Conventional and Ohmic Heating Extraction and Its Prebiotic Properties
2023
Several studies have supported the positive functional health effects of both prebiotics and probiotics on gut microbiota. Among these, the selective growth of beneficial bacteria due to the use of prebiotics and bioactive compounds as an energy and carbon source is critical to promote the development of healthy microbiota within the human gut. The present work aimed to assess the fermentability of tomato flour obtained after ohmic (SFOH) and conventional (SFCONV) extraction of phenolic compounds and carotenoids as well as their potential impact upon specific microbiota groups. To accomplish this, the attained bagasse flour was submitted to an in vitro simulation of gastrointestinal digestion before its potential fermentability and impact upon gut microbiota (using an in vitro fecal fermentation model). Different impacts on the probiotic strains studied were observed for SFCONV promoting the B. animalis growth, while SFOH promoted the B. longum, probably based on the different carbohydrate profiles of the flours. Overall, the flours used were capable of functioning as a direct substrate to support potential prebiotic growth for Bifidus longum. The fecal fermentation model results showed the highest Bacteroidetes growth with SFOH and the highest values of Bacteroides with SFCONV. A correlation between microorganisms’ growth and short-chain fatty acids was also found. This by-product seems to promote beneficial effects on microbiota flora and could be a potential prebiotic ingredient, although more extensive in vivo trials would be necessary to confirm this.
Journal Article
Carotenoids and Intestinal Harmony: Exploring the Link for Health
by
Gomes, Ana M.
,
Rocha, Helena R.
,
Pintado, Manuela E.
in
Acetic acid
,
Acid production
,
Bacteria
2024
Carotenoids, prominent lipid-soluble phytochemicals in the human diet, are responsible for vibrant colours in nature and play crucial roles in human health. While they are extensively studied for their antioxidant properties and contributions to vitamin A synthesis, their interactions with the intestinal microbiota (IM) remain poorly understood. In this study, beta (β)-carotene, lutein, lycopene, a mixture of these three pigments, and the alga Osmundea pinnatifida were submitted to simulated gastrointestinal digestion (GID) and evaluated on human faecal samples. The results showed varying effects on IM metabolic dynamics, organic acid production, and microbial composition. Carotenoid exposure influenced glucose metabolism and induced the production of organic acids, notably succinic and acetic acids, compared with the control. Microbial composition analysis revealed shifts in phyla abundance, particularly increased Pseudomonadota. The α-diversity indices demonstrated higher diversity in β-carotene and the pigments’ mixture samples, while the β-diversity analysis indicated significant dissimilarity between the control and the carotenoid sample groups. UPLC-qTOF MS analysis suggested dynamic changes in carotenoid compounds during simulated fermentation, with lutein exhibiting distinct mass ion fragmentation patterns. This comprehensive research enhances our understanding of carotenoid-IM interactions, shedding light on potential health implications and the need for tailored interventions for optimal outcomes.
Journal Article
Association between pre‐sarcopenia, sarcopenia, and bone mineral density in patients with chronic hepatitis C
by
Silva, Luciana D.
,
Queiroz, Dulciene M.M.
,
Correia, Maria Isabel T.D.
in
Adult
,
Aged
,
Appendicular skeletal muscle mass
2018
Background Preserved skeletal muscle is essential for the maintenance of healthy bone. Loss of bone mineral density (BMD) and muscle strength, considered a predictor of BMD, have been demonstrated in patients with cirrhosis, but they are poorly studied in chronic hepatitis C (CHC) without cirrhosis. Thus, we aimed to evaluate the prevalence of low BMD and its association with body composition, muscle strength, and nutritional status in CHC. Methods One hundred and four subjects [mean age, 50.5 ± 11.3 years; 75.0% males; 67.3% non‐cirrhotic; and 32.7% with compensated cirrhosis] with CHC, prospectively, underwent scanning of the lean tissue, appendicular skeletal muscle mass (ASM), fat mass, lumbar spine, hip, femoral neck, and whole‐body BMD by dual‐energy X‐ray absorptiometry. Muscle strength was assessed by dynamometry. Sarcopenia was defined by the presence of both low, ASM/height2 (ASMI) and low muscle strength according to the European Working Group on Sarcopenia in Older People criteria. The cut‐off points for low ASMI and low muscle strength, for women and men, were < 5.45 and < 7.26 kg/m2 and < 20 and < 30 kg, respectively. According to the adopted World Health Organization criteria in men aged > 50 years, the T‐score of osteopenia is between −1.0 and −2.49 standard deviation (SD) below the young average value and of osteoporosis is ≥−2.5 SD below the young normal mean for men, and the Z‐score of low bone mass is ≤−2.0 SD below the expected range in men aged < 50 years and women in the menacme. Nutritional status evaluation was based on the Controlling Nutritional Status score. Results Low BMD, low muscle strength, pre‐sarcopenia, sarcopenia, and sarcopenic obesity were observed in 34.6% (36/104), 27.9% (29/104), 14.4% (15/104), 8.7% (9/104), and 3.8% (4/104) of the patients, respectively. ASMI was an independent predictor of BMD (P < 0.001). Sarcopenia was independently associated with bone mineral content (P = 0.02) and malnutrition (P = 0.01). In 88.9% of the sarcopenic patients and in all with sarcopenic obesity, BMI was normal. The mid‐arm muscle circumference was positively correlated with ASMI (r = 0.88; P < 0.001). Conclusions This is the first study to demonstrate that ASM is an independent predictor of BMD in CHC. Mid‐arm muscle circumference coupled with handgrip strength testing should be incorporated into routine clinical practice to detect low muscle mass, which may be underdiagnosed when only BMI is used. These findings may influence clinical decision‐making and contribute to the development of effective strategies to screen the musculoskeletal abnormalities in CHC patients, independently of the stage of the liver disease.
Journal Article
Unrealistic Optimism: Still a Neglected Trait
Purpose Unrealistic optimism is all around us, and it is a well-documented psychological phenomenon. The purpose of this study is to take a critical approach of the main research done in the area and to analyze the important impact that it has in many economic and managerial contexts. We also analyze current trends in terms of entrepreneurship by policy makers. Findings We show that most people are prone to groundless optimism when faced with economic and managerial decisions and yet economists, managers and policy makers still ignore it or fail to understand its characteristics. Implications Since the policy and welfare implications of such a (neglected) widespread phenomenon are vast, we challenge the current public policy trend of extending lending to business start-ups, on the grounds that it may create a real road to ruin. Originality/value A careful analysis of the psychology of over-optimism from an economics and managerial perspective is original and extremely valuable in a world where uncertainty dominates. Methodology/approach Critical review of the existing literature on unrealistic optimism and its implications for economic and managerial decision making.
Journal Article