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- Chemical composition of red, brown and green macroalgae from Buarcos bay in Central West Coast of PortugalPublication . Rodrigues, Dina; Freitas, Ana C.; Pereira, Leonel; Rocha-Santos, Teresa A. P.; Vasconcelos, Marta W.; Roriz, Mariana; Rodríguez-Alcalá, Luís M.; Gomes, Ana M. P.; Duarte, Armando C.Six representative edible seaweeds from the Central West Portuguese Coast, including the less studied Osmundea pinnatifida, were harvested from Buarcos bay, Portugal and their chemical characterization determined. Protein content, total sugar and fat contents ranged between 14.4% and 23.8%, 32.4% and 49.3% and 0.6–3.6%. Highest total phenolic content was observed in Codium tomentosum followed by Sargassum muticum and O. pinnatifida. Fatty acid (FA) composition covered the branched chain C13ai to C22:5 n3 with variable content in n6 and n3 FA; low n6:n3 ratios were observed in O. pinnatifida, Grateloupia turuturu and C. tomentosum. Some seaweed species may be seen as good sources of Ca, K, Mg and Fe, corroborating their good nutritional value. According to FTIR-ATR spectra, G. turuturu was associated with carrageenan seaweed producers whereas Gracilaria gracilis and O. pinnatifida were mostly agar producers. In the brown algae, S. muticum and Saccorhiza polyschides, alginates and fucoidans were the main polysaccharides found.
- Bioactive sugarcane lipids in a circular economy contextPublication . Teixeira, Francisca S.; Vidigal, Susana S.M.P.; Pimentel, Lígia L.; Costa, Paula T.; Pintado, Manuela E.; Rodríguez-Alcalá, Luís M.Most of the global sugar and ethanol supply trade comes from the harvesting of Saccharum officinarum (i.e., sugarcane). Its industrial processing results in numerous by-products and waste streams, such as tops, straw, filter cake, molasses and bagasse. The recovery of lipids (i.e., octacosanol, phytosterols, long-chain aldehydes and triterpenoids) from these residues is an excellent starting point for the development of new products for various application fields, such as health and well-being, representing an important feature of the circular economy. By selecting green scalable extraction procedures, industry can reduce its environmental impact. Refluxed ethanol extraction methods have been demonstrated to meet these characteristics. On the other hand, effective non-solvent methodologies such as molecular distillation and supercritical CO2 extraction can fractionate lipids based on high temperature and pressure application with similar yields. Sugarcane lipophilic extracts are usually analyzed through gas chromatography (GC) and liquid chromatography (LC) techniques. In many cases, the identification of such compounds involves the development of high-temperature GC–MS/FID techniques. On the other hand, for the identification and quantification of thermolabile lipids, LC–MS techniques are suitable for the separation and identification of major lipid classes. Generically, its composition includes terpenes, phytosterols, tocopherol, free fatty acids, fatty alcohols, wax esters, triglycerides, diglycerides and monoglycerides. These compounds are already known for their interesting application in various fields such as pharma and cosmetics due to their anti-hypercholesterolemic, anti-hyperglycemic, antioxidant and anti-inflammatory properties.
- Lactobacillus mulieris sp. nov., a new species of Lactobacillus delbrueckii groupPublication . Rocha, Joana; Botelho, João; Ksiezarek, Magdalena; Ugarcina Perovic, Svetlana; Machado, Miguel; Carrico, João André; Pimentel, Lígia L.; Salsinha, Sofia; Rodríguez-Alcalá, Luis M.; Pintado, Manuela; Ribeiro, Teresa G.; Peixe, LuísaOne Gram-stain-positive, non-motile, non-spore-forming, catalase-negative, and coccobacilli-shaped strain, designated c10Ua161MT, was isolated from a urine sample from a reproductive-age healthy woman. Comparative 16S rRNA gene sequence analysis indicated that strain c10Ua161MT belonged to the genus Lactobacillus . Phylogenetic analysis based on pheS and rpoA gene sequences strongly supported a clade encompassing strains c10Ua161MT and eight other strains from public databases, distinct from currently recognized species of the genus Lactobacillus. In silico Average Nucleotide Identity (ANI) and Genome-to-Genome Distance Calculator (GGDC), showed 87.9 and 34.3 % identity to the closest relative Lactobacillus jensenii , respectively. The major fatty acids of strain c10Ua161MT were C18 : 1ω9c (65.0%), C16 : 0 (17.8%), and summed feature 8 (10.2 %; comprising C18 : 1ω7c, and/or C18 : 1ω6c). The DNA G+C content of the strains is 34.2 mol%. On the basis of data presented here, strain c10Ua161MT represents a novel species of the genus Lactobacillus , for which the name Lactobacillus mulieris sp. nov. is proposed. The type strain is c10Ua161MT (=CECT 9755T=DSM 108704T).
- Alterations in the fatty acid composition in infant formulas and ω3‐PUFA enriched UHT milk during storagePublication . Rodríguez‐Alcalá, Luis Miguel; Calvo, María V.; Fontecha, Javier; Alonso, Leocadioω3-polyunsaturated fatty acids (PUFA) are known to have several beneficial effects, such as preventing the occurrence of cardiovascular events in adults and improving the development of the central nervous system during fetal life and childhood. Dairy products enriched in PUFA are now available on the market and can help consumers to meet the ω3-PUFA daily intake recommendations. Although PUFA are prone to oxidation, little information exists regarding the alterations they undergo when products containing PUFA are stored. In this study, five infant formulae (IF) and five ω3-PUFA enriched Ultra High Temperature (UHT)-milk products were examined during storage at room temperature in terms of fatty acid (FA) composition and trans fatty acid (tFA) content until the end of shelf life by chromatography techniques. The IF included two follow-on formulae, two first-age formulae and a special medical purpose formula with different fat contents (from 2.6% to 27.7%). In the ω3-PUFA enriched UHT-milk products the milk fat was replaced by eicosapentanoic fatty acid (EPA) and docosahexaenoic acid (DHA) rich oils. The fatty acid content of all samples remained stable whereas some variations were observed for the tFA isomer content (p < 0.05) in the UHT-milk samples.
- Suitable simple and fast methods for selective isolation of phospholipids as a tool for their analysisPublication . Pimentel, Lígia; Fontes, Ana Luiza; Salsinha, Sofia; Machado, Manuela; Correia, Inês; Gomes, Ana Maria; Pintado, Manuela; Rodríguez-Alcalá, Luis MiguelLipids are gaining relevance over the last 20 years, as our knowledge about their role has changed from merely energy/structural molecules to compounds also involved in several biological processes. This led to the creation in 2003 of a new emerging research field: lipidomics. In particular the phospholipids have pharmacological/food applications, participate in cell signalling/homeostatic pathways while their analysis faces some challenges. Their fractionation/purification is, in fact, especially difficult, as they are amphiphilic compounds. Moreover, it usually involves SPE or TLC procedures requiring specific materials hampering their suitableness for routine analysis. Finally, they can interfere with the ionization of other molecules during mass spectrometry analysis. Thus, simple high‐throughput reliable methods to selectively isolate these compounds based on the difference between chemical characteristics of lipids would represent valuable tools for their study besides that of other compounds. The current review work aims to describe the state‐of‐the‐art related to the extraction of phospholipids using liquid‐liquid methods for their targeted isolation. The technological and biological importance of these compounds and ion suppression phenomena are also reviewed. Methods by precipitation with acetone or isolation using methanol seem to be suitable for selective isolation of phospholipids in both biological and food samples.
- Lipidomic characterization of the milk fat globule membrane polar lipidsPublication . Montero, Olimpio; Fontecha, Javier; Castro-Gómez, M. Pillar; Rodríguez-Alcalá, Luis Miguel
- Effect of chronic consumption of blackberry extract on high-fat induced obesity in rats and its correlation with metabolic and brain outcomesPublication . Meireles, Manuela; Rodríguez-Alcalá, Luís M; Marques, Cláudia; Norberto, Sónia; Freitas, Joana; Fernandes, Iva; Mateus, Nuno; Gomes, Ana Maria; Faria, Ana; Calhau, ConceiçãoFlavonoids have been presented as potential protectors against metabolic and cognitive dysfunction. However, mechanisms underlying these 'claims' have not been sufficiently explored. To analyse the effect of long-term supplementation with blackberry extract (BE) in the context of a high-fat or a standard diet, Wistar rats were divided into 4 groups (n = 6) fed with a standard or a high-fat diet, with or without BE supplementation at 25 mg per kg body weight per day. A high-fat diet significantly impaired glucose tolerance and increased body weight, caloric ingestion, very-low-density lipoprotein, triglycerides and cholesterol. Furthermore, it was observed that a high-fat diet increased dopamine content in the prefrontal cortex and decreased brain derived neurotrophic factor (BDNF) levels both in the prefrontal cortex and in plasma. BE supplementation only affected some of these aspects. BE slightly improved glucose metabolism and significantly decreased levels of lactate, independent of diet. BE decreased levels of BDNF and also interacted with the dopaminergic system, increasing dopamine turnover in the striatum, and reverting dopamine content induced by a high-fat diet in the prefrontal cortex. This study shows that, despite some particular benefits of anthocyanin supplementation, some long-term effects may not be desirable and further studies are needed to optimize ingestion conditions.
- Fermentation of bioactive solid lipid nanoparticles by human gut microfloraPublication . Madureira, Ana Raquel; Campos, Débora; Gullon, Beatriz; Marques, Cláudia; Rodríguez-Alcalá, Luís M.; Calhau, Conceição; Alonso, Jose Luis; Sarmento, Bruno; Gomes, Ana M.; Pintado, M. E.Solid lipid nanoparticles (SLNs) can be used for oral delivery of phenolic compounds in order to protect them from the harsh conditions of digestion and improve their bioavailability in the intestinal epithelium. Recently, the production and characterization of SLNs loaded with rosmarinic acid (RA) and herbal extracts was performed for future use as functional food ingredients. Diet components have been shown to have a huge impact on gut microbiota viability and metabolic activity. Hence, SLNs loaded with RA, sage and savoury extracts have been evaluated for their effect on intestinal microbiota growth and the metabolic products generated. Fermentations in anaerobic batch cultures using volunteer human faeces were performed during 24 h. Dynamic bacterial population changes were analysed using PCR-real time, as well as the generation of fatty acids and the quantification of phenolic compounds by analytical methods. Solid lipid nanoparticles released phenolic compounds at non-inhibitory bacterial growth concentrations. Released herbal extract phenolic compounds showed a beneficial effect on gut microbiota growth (e.g. bifidogenic effects) and were used as substrates. Acetate, formate, lactate and butyrate were produced in higher concentrations. The released phenolic compounds also induced PUFA and trans fatty acids metabolic activity, the production of saturated fatty acids, as well of potential beneficial conjugated linoleic acid isomers. Solid lipid nanoparticles modulate gut microbiota and metabolic activities.
- Microbiological in vivo production of CLNA as a tool in the regulation of host microbiota in obesity controlPublication . Pimentel, Lígia Leão; Fontes, Ana Luiza; Salsinha, Ana Sofia; Cardoso, Beatriz Batista; Gomes, Ana Maria; Rodríguez-Alcalá, Luís MiguelMetabolic disorders associated with dietary patterns have become a social and economic problem. Obesity is indeed considered a central feature that increases the risks associated with a vast array of diseases (insulin resistance, type 2 diabetes, fatty liver disease, atherosclerosis, hypertension, stroke, cancer, and asthma), with significant morbidity and mortality. Although lipids may be involved in the development of these illnesses, recent studies have stated their role as cellular mediators and they have been assayed as bioactive compounds in possible treatments. Clear examples are the conjugated isomers of linoleic acid (CLA), which have been associated with antiatherogenic, antioxidative, immunostimulation, and body fat reduction activities. Recently, increased interest in other conjugated PUFAs has emerged, linked to the health-promoting properties of conjugated linolenic acid isomers (CLnA) like C18:3 c9t11c15 (rumelenic acid, RLA). These fatty acids combine in the same molecule a double conjugated bond system with the n3 structure of linolenic acid (ALA; C18:3 c9c12c15) resulting in a high bioactive potential. Animal studies have revealed that CLnA regulates leptin production and increases β-oxidation in the liver thus reducing perirenal and epididymal adipose tissue. Elsewhere it was reported that RLA increased PPARα levels in adipocytes, which suggests that it is a candidate functional ingredient for use in the prevention of obesity, diabetes, and dyslipidemia. CLA and CLnA are natural fatty acids (FAs) mainly found in dairy products and beef, because they are produced as intermediates of the biohydrogenation pathway of PUFAs by ruminal bacteria. Therefore it is hypothesized that other microorganisms may also be able to produce CLA and conjugated FAs. Indeed, recent investigations demonstrated that it is possible to elaborate fermented dairy products containing CLA and CLnA produced by these bacteria. Other authors have identified Bifidobacterium strains with a high rate of substrate conversion to yield CLA, CLnA, and stearidonic acids producing these FAs in vivo, increasing the RA concentration in murine and pigs livers as well as DHA and EPA in mice adipose tissue. An important issue arises from these results: host fatty acid composition can be manipulated by oral administration of CLA-producing microorganisms. In the last 5 years an increasing number of studies have found strong evidence of the role not only of diet but also of human gut microbiota in the development of diabetes and obesity. Indeed, host microbiota regulates the content of triglycerides, cholesterol esters, sphingomyelin, and phosphatidylcholine in the plasma, liver, and adipose tissue as well as energy metabolites. This chapter will review the current state-of-the-art microbiological in vivo production of CLA and CLnA and its effect on host microbiota and health.
- Milk fat components with potential anticancer activity - a reviewPublication . Rodríguez-Alcalá, Luis M.; Castro-Gómez, M. Pilar; Pimentel, Lígia L.; Fontecha, JavierDuring many years, the milk fat has been unfairly undervalued due to its association with higher levels of cardiovascular diseases, dyslipidaemia or obesity, among others. However, currently, this relationship is being re-evaluated because some of the dairy lipid components have been attributed potential health benefits. Due to this, and based on the increasing incidence of cancer in our society, this review work aims to discuss the state of the art concerning scientific evidence of milk lipid components and reported anticancer properties. Results from the in vitro and in vivo experiments suggest that specific fatty acids (FA) (as butyric acid and conjugated linoleic acid (CLA), among others), phospholipids and sphin-golipids from milk globule membrane are potential anticarcinogenic agents. However, their mechanism of action remains still unclear due to limited and inconsistent findings in human studies.
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