Active aroma compounds assessment of processed and non-processed micro- and macroalgae by solid-phase microextraction and gas chromatography/mass spectrometry targeting seafood analogs

The Supplementary Material for this article can be found online at: https://www.frontiersin.org/articles/10.3389/ fsufs.2022.1011020/full#supplementary-materialThe odor of four algae was investigated and compared to evaluate the potential of these algae to mimic shrimp aroma. Solid-phase microextraction followed by gas chromatography analysis coupled with sensory analysis was used for performance assessment. The volatile organic compounds were determined in non-processed, raw samples (r), and processed cooked (c) and cooking water (w) samples for two microalgae [Nannochoropsis oceanica (NO) and Tetraselmis chuii (TC)], two macroalgae [Ulva rígida (UR) and Saccharina latíssima (SL)], and shrimp Vannamei cong (SH). The results showed significant differences in the composition of volatile compounds between macroalgae and microalgae. The key odorants in macroalgae were octanal, 2-octenal, nonanal, and β-ionone, and in microalgae were 1,5-octadien-3-ol, hexanal, 2,4-decadienal, 2-octenal, octanal, nonanal, 3,5-octadien-2-one, and terpenes. The PCA analysis of GC-MS data showed odor similarities between the studied samples, which were divided into five main groups: (1) TC(c) and TC(w); (2) TC(r) and NO(c); (3) NO(r), NO(w), and SL(w); (4) SL(c), UR(r), UR(c), and UR(w); and (5) SL(r). The data from the sensory analysis show bigger similarities between the macroalgae and the shrimp odor. Overall, the data provided indicate that the cooking water and cooked samples are very similar in key components of odorants. These features allow the possibility to use algae and their processed resulting products as a shrimp flavor replacement in non-animal-based food formulations, thus decreasing the pressure on seafood crops and aquaculture-associated issues leading to more sustainable livestock. Furthermore, circularity and waste reduction may be further enabled by the use of otherwise wasted cooking water as an odorant agent.This study was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UIDB/04469/2020 unit and by LABBELS— Associate Laboratory in Biotechnology, Bioengineering and Microelectromechanical Systems, LA/P/0029/2020. This study was also funded by the ESIF—European Structural and Investment Funds under the scope of the projects ALGAVALOR—Microalgae integrated production and valorization of its various applications (ref. POCI-01-0247-FEDER-035234; LISBOA-01-0247-FEDER-035234; ALG-01-0247-FEDER-035234; through Portugal 2020), and BioEcoNorte project (ref. NORTE-01-0145-FEDER-000070, through Portugal 2020 and Norte2020). CM is recipient of a Ph.D. scholarship supported by FCT (Ref. 2021.05734.BD).info:eu-repo/semantics/publishedVersio

Analysis of the profile of volatile organic compounds in Chlorella vulgaris

It is known that the incorporation of microalgae into foodstuffs enables to modify the overall flavor leading to desirable or undesirable organoleptic properties. Nevertheless, few were the studies conducted focusing on the analysis of the profile of volatile organic compounds (VOCs) produced by microalgae, which are the main compounds responsible for the aroma perception. The aim of this study was to analyze the VOCs profile of Chlorella vulgaris powder by gas chromatography coupled with mass spectrometry (GC-MS). Different techniques were used for the extraction of the VOCs, prior to the chromatographic analysis: 1) solid-phase microextraction (SPME), and 2) ultrasound-assisted liquid extraction (UALE) using five different solvents. For the SPME analysis, 0.5 g of C. vulgaris was exposed to a divinylbenzene/carboxen/polydimethylsiloxane (DVB/CAR/PDMS) fiber and was desorbed for 5 min into GC-MS. For the UALE, 2 g of sample was placed in five different solvents for extraction (chloroform, dichloromethane, hexane, ethyl acetate and acetone). For both SPME and UALE the GC-MS analysis was performed on Stabilwax (SW) and RXI-5 columns. The results showed very different profiles of VOCs between columns and techniques of extractions. In the analysis with the SW column no compounds were detected in acetone, hexane and ethyl acetate and only a few were present with the chloroform (39 VOCs) and dichloromethane (15 VOCs) extraction when compared to SPME (75 VOCs). In the RXI-5 analysis, a reduced number of compounds was identified when comparing with SW in SPME (39 and 75 VOCs, respectively), and in UALE, ethyl acetate was the only solvent with any retention of VOCs that could be detected with this column, having chloroform, dichloromethane, acetone and hexane, 10, 10, 5, and 8 VOCs respectively. In SPME, the main chemical classes of identified VOCs were, alcohols and hydrocarbons. In UALLE, the VOCs profile was more balanced with alcohols, aldehydes, carboxy group, ketones and hydrocarbons. Only with hexane it was possible to find aromatic groups. Compounds such as hexanal, tetradecane, and 3-methylbutanal were found in SPME as reported in literature, although 3-methylbutanal was only present for SW. In conclusion, SPME run in a SW column showed more VOCs retention and seems to be more appropriate to enable aroma prediction in C. vulgaris-based foodstuff.Portuguese Foundation for Science and Technology (FCT) - 2021.05734.BDinfo:eu-repo/semantics/publishedVersio

Synthesis of 2,6-bis-(oxazolyl)pyridine ligands for luminescent Ln(III) complexes

Submitted to the European Journal of Organic ChemistryNew bis-(oxazolyl)pyridine ligands for Ln(III) ions were prepared using a expeditious methodology from threonine and dipicolinic acid chloride. The synthetic strategy includes a dehydration step to give a bis-dehydroaminobutyric acid derivative followed by bromination and cyclization with DBU. Photophysical studies of Eu(III) and Tb(III) complexes of these ligands showed that the 2,6-bis-(oxazolyl)pyridine moiety acts as an effective sensitizer for lanthanide luminescence and indicate the formation of 3:1 complexes [Ln-(bis-(oxazole)pyridine)3]3+.Fundação para a Ciência e Tecnologia (FCT), QREN, FEDER/E

Osborne fractionation: an approach for red macroalgae proteinassessment

Although animal sources enhance consumers' nutritional satisfaction, their cost, consumers dietary restrictions, as well as an increasing interest in vegetarianism, organic food and locally grown foods emphasizes the importance of finding new sustainable alternatives of protein sources in order to satisfy anticipated increased global needs without magnifying the negative impact. Porphyra dioica, Gracilaria verrucosa and Chondrus crispus are examples of red algae species that are used as a source of valuable compounds that can satisfy the demand for different foods and help to decrease the impact on animals use as the main food nutrients supplier. Since there are a wide range of different proteins in macroalgae, it is important to study and assess which kind of proteins are present in different species, which will help to predict if they can be used to replace some conventional animal proteins. The main objective of this work was the application of Osborne method for protein recovery from red algae species using different solvents (e.g., H2O, NaCl, EtOH and NaOH). The produced fractions were characterized in terms of extraction yields, protein content (Lowry method) and molecular weight by gel electrophoresis (SDS-PAGE). Results showed that the maximum protein content was obtained for Porphyra dioica and the minimum value for Chondrus crispus (i.e., 29.12 and 7.13 %, respectively). Regarding Osborne fractionation, all species showed higher protein content in water and NaOH resulting proteins fractions, being the best results associated with Gracilaria verrucosa, with a total protein extraction yield (gprotein/gbiomass) of 12.39 %. Comparing to the initial protein content of Gracilaria verrucosa (17.45 ± 0.05 %dw) it is possible extract 70.99 % of total protein where 35.83 % and 18.05 % corresponds to water and NaOH fractions, respectively. From the SDS-PAGE gels it is clearly visible that different species showed proteins with different molecular weights. Thus, it can be concluded that the Osborne method is a promising approach to characterize algal protein and can help choosing the best conditions for higher protein recovery from red macroalgae. The extracted proteins may be applied into different food prototypes in order to substitute conventional animal protein sources.Portuguese Foundation for Science and Technology (FCT) - UIDB/04469/2020 unit and SFRH/BD/07527/2020; BioEcoNorte project (NORTE-01-0145-FEDER-000070); NORTE 2020 (Programa Operacional Regional do Norte 2014/2020); Portugal 2020; ESIF- European structural and investment funds.info:eu-repo/semantics/publishedVersio

Secretome of Mesenchymal Progenitors from the Umbilical Cord Acts as Modulator of Neural/Glial Proliferation and Differentiation

It was recently shown that the conditioned media (CM) of Human Umbilical Cord Perivascular Cells (HUCPVCs), a mesenchymal progenitor population residing within the Wharton Jelly of the umbilical cord, was able to modulate in vitro the survival and viability of different neuronal and glial cells populations. In the present work, we aimed to assess if the secretome of HUCPVCs is able to 1) induce the differentiation of human telencephalon neural precursor cells (htNPCs) in vitro, and 2) modulate neural/glial proliferation, differentiation and survival in the dentate gyrus (DG) of adult rat hippocampus. For this purpose, two separate experimental setups were performed: 1) htNPCs were incubated with HUCPVCs-CM for 5 days after which neuronal differentiation was assessed and, 2) HUCPVCs, or their respective CM, were injected into the DG of young adult rats and their effects assessed 7 days later. Results revealed that the secretome of HUCPVCs was able to increase neuronal cell differentiation in vitro; indeed, higher densities of immature (DCX+ cells) and mature neurons (MAP-2(+) cells) were observed when htNPCs were incubated with the HUCPVCs-CM. Additionally, when HUCPVCs and their CM were injected in the DG, results revealed that both cells or CM were able to increase the endogenous proliferation (BrdU(+) cells) 7 days after injection. It was also possible to observe an increased number of newborn neurons (DCX+ cells), upon injection of HUCPVCs or their respective CM. Finally western blot analysis revealed that after CM or HUCPVCs transplantation, there was an increase of fibroblast growth factor-2 (FGF-2) and, to a lesser extent, of nerve growth factor (NGF) in the DG tissue. Concluding, our results have shown that the transplantation of HUCPVCs or the administration of their secretome were able to potentiate neuronal survival and differentiation in vitro and in vivo.Foundation Calouste Gulbenkian for funds under the scope of the Gulbenkian Programme to Support Cutting Edge Research in Life Sciences; Portuguese Foundation for Science and Technology (FCT) for Ciência 2007 program and IF Development Grant (A.J. Salgado), and pre-doctoral fellowship to F.G. Teixeira (SFRH / BD / 69637 / 2010); John E. Davies for kindly providing the HUCPVCs used in this workinfo:eu-repo/semantics/publishedVersio

Gold nanoparticles functionalised with stable, fast water exchanging Gd3+ chelates as high relaxivity contrast agents for MRI

Gold nanoparticles functionalized with Gd3+ chelates displaying fast water exchange, superb pH stability and inertness towards transmetalation with Zn2+ have been prepared and characterized as a new high relaxivity (29 mM-1s-1, 30 MHz, 25 ºC) Contrast Agent potentially safe for in vivo MRI applications. The Lipari-Szabo treatment for internal rotation was used to evaluate the effect of linker flexibility on the relaxivity of the gold nanoparticles. The relaxivity is limited by chelate flexibility. The effect of fast water exchange on the relaxivity of gold nanoparticles functionalized with Gd3+ chelates is also addressed in this communication.Fundação para a Ciência e TecnologiaProjecto PTDC/QUI/70063/2006PhD grant SFRH/BD/63994/2008 to Miguel FerreiraRede Nacional de RMN REDE/1517/RMN/2005 for the acquisition of the Varian VNMRS 600 NMR spectrometer in Coimbra and the Bruker Avance-3 400 Plus in BragaB. Mousavi and L. Helm acknowledge financial support by the Swiss National Science Foundation.COST D38 Actio

Use of plant seed galactomannans as edible coatings

[Excerpt] Edible films and coatings play an important role in the quality, transportation, storage and display of a wide range of fresh and processed foods. Polysaccharide coatings have an oil-free appearance, a low caloric content and can be used to increase the shelf life of fresh fruits, since they allow the modification of the internal gas composition of fruits, thus retarding its senescence. The objective of this work was to study the ability of seed galactomannans, with different man:gal rations, from different species of Leguminosae (Caesalpinea pulcherrima (2.8:1), Gleditsia triacanthos (2.26:1) and Sophora japonica (5.26:1) to be used as coatings to extend the shelf life of mango (Mangifera indica) fruit. [...]info:eu-repo/semantics/publishedVersio

Edible coatings of galactomannan/collagen in fruit shelf life extension

Short shelf life is of the upmost importance in fruit conservation. As living organisms, fruits maintain metabolism after harvesting, and its shelf-life can be extended by reducing respiration rates. This can be done by controlling factors such as temperature, light, humidity and gas composition (ethylene, O2 and CO2). To control these, an important strategy is the use of modified atmospheres, with low caloric galactomannan coatings. Collagen coatings have, also, already been used on meat and sausage to reduce gas and/or water vapor permeability (WVP). In this work the preparation novel edible coatings, based on the mixture of galactomannan, collagen and glycerol, was investigated, and their influence in gas transfer rates in mangoes and apples evaluated. The gas permeability properties of the coatings, presenting the best values of wettability (previously determined), were tested. Mangoes coated with an Adenanthera pavonina seed endospermic galactomannan-collagen-glycerol solution were studied and the gas transfer rates compared with no coated mangoes. Gas transfer rate was calculated and )28% O2 consumption and )11% CO2 production were observed in coated mangoes. The same procedure was done (using Caesalpinea pulcherrima galactomannan) in apples. The CO2 production and O2 consumption were approximately 50% lower in coated apples. These results suggest that these coatings, reducing gas transfer rates, may be important tools to extend fruit shelf-life.info:eu-repo/semantics/publishedVersio

ELSA-Brasil: a 4-year incidence of hearing loss in adults with and without hypertension

OBJECTIVE To compare the incidence of hearing loss among adults stratified by the occurrence of hypertension, and to investigate the association between hypertension and hearing loss. METHODS Longitudinal observational study, part of the Estudo Longitudinal da Saúde do Adulto (ELSA-Brasil, Longitudinal Study on Adult’s Health). Data from the first and second waves were analyzed, including information from audiological assessment and general health of the subjects. As outcome, we considered the presence of hearing loss (hearing thresholds above 25 dBHL at frequencies from 500 Hz to 8 kHz) and, as exposure variable, hypertension (report of medical diagnosis of hypertension; and/or use of drugs to treat hypertension; and/or pressure systolic blood pressure ≥ 140 mmHg; or diastolic blood pressure ≥ 90 mmHg). As covariables for adjustment were considered: sex, age, education, race / ethnicity, income, smoking, diabetes, and occupational exposure to noise. Poisson regression analysis was conducted, estimating the crude and adjusted relative risks, with 95% confidence intervals, in order to assess the factors associated with hearing loss. RESULTS In crude analyses, the incidence of hearing loss was higher for subjects with hypertension (9.7% versus 5.4%). The crude relative risks for hearing loss was almost double (1.93; 95%CI: 1.10–3.39) for subjects with hypertension in the right ear. In the adjusted analyses, the relative risks was not significant for the hypertension variable (1.42; 95%CI: 0.75–2.67). Being 60 years or older (RR: 5.41; 95%CI: 2.79–10.50) showed a statistically significant association with hearing loss, indicating that older adults have higher relative risks for hearing loss. CONCLUSION In the adjusted analyses controlled for multiple risk factors there was no association between hypertension and hearing loss. The dichotomous variable age (being 60 years or older), on the other hand, has shown a significant association with hearing loss

Rationale, design and methodology for Intraventricular Pressure Gradients Study: a novel approach for ventricular filling assessment in normal and falling hearts

<p>Abstract</p> <p>Background</p> <p>Intraventricular pressure gradients have been described between the base and the apex of the left ventricle during early diastolic ventricular filling, as well as, their increase after systolic and diastolic function improvement. Although, systolic gradients have also been observed, data are lacking on their magnitude and modulation during cardiac dysfunction. Furthermore, we know that segmental dysfunction interferes with the normal sequence of regional contraction and might be expected to alter the physiological intraventricular pressure gradients. The study hypothesis is that systolic and diastolic gradients, a marker of normal left ventricular function, may be related to physiological asynchrony between basal and apical myocardial segments and they can be attenuated, lost entirely, or even reversed when ventricular filling/emptying is impaired by regional acute ischemia or severe aortic stenosis.</p> <p>Methods/Design</p> <p><it>Animal Studies: </it>Six rabbits will be completely instrumented to measuring apex to outflow-tract pressure gradient and apical and basal myocardial segments lengthening changes at basal, afterloaded and ischemic conditions. Afterload increase will be performed by abruptly narrowing or occluding the ascending aorta during the diastole and myocardial ischemia will be induced by left coronary artery ligation, after the first diagonal branch.</p> <p><it>Patient Studies: </it>Patients between 65-80 years old (n = 12), both genders, with severe aortic stenosis referred for aortic valve replacement will be selected as eligible subjects. A high-fidelity pressure-volume catheter will be positioned through the ascending aorta across the aortic valve to measure apical and outflow-tract pressure before and after aortic valve replacement with a bioprosthesis. Peak and average intraventricular pressure gradients will be recorded as apical minus outflow-tract pressure and calculated during all diastolic and systolic phases of cardiac cycle.</p> <p>Discussion</p> <p>We expect to validate the application of our method to obtain intraventricular pressure gradients in animals and patients and to promote a methodology to better understand the ventricular relaxation and filling and their correlation with systolic function.</p