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1.
Mass Spectrom Rev ; 2023 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-37279164

RESUMO

Analysis of triacylglycerol (TG) and phospholipid sn-positional isomers can be divided into two main categories: (a) direct separation by chromatography or other means such as ion mobility mass spectrometry and (b) quantification of regioisomer ratios by structurally informative fragment ions with mass spectrometric methods. Due to long retention times and limited performance, researchers are moving away from direct chromatographic separation of isomers, using mass spectrometry instead. Many established analytical methods are targeting specific isomers of interest instead of untargeted analysis of comprehensive profiles of regioisomers. Challenges remain arising from the large number of isobaric and isomeric lipid species in natural samples, often overlapping chromatographically and sharing structurally informative fragment ions. Further, fragmentation of glycerolipids is influenced by the nature of the attached fatty acids, and the lack of available regiopure standards is still an obstacle for establishing calibration curves required for accurate quantification of regioisomers. Additionally, throughput of many methods is still quite limited. Optimization algorithms and fragmentation models are useful especially for analysis of TG regioisomers, as identification using calibration curves alone without proper separation is difficult with complex samples.

2.
J Exp Bot ; 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38630600

RESUMO

Kales (Brassica oleracea convar acephala) are fast-growing, nutritious leafy vegetables ideal for year-round indoor farming. However, selection of best cultivars for growth under artificial lighting necessitates a deeper understanding of leaf metabolism in different kale types. Here we examined a curly leaved cultivar Half Tall and a lacinato type cultivar Black Magic under moderate growth light (130 µmol photons m-1s-1/22°C) and high light (800 µmol photons m-1s-1/26°C) conditions. These conditions induced genotype-dependent differences in nutritionally important metabolites, especially anthocyanins and glucosinolates (GSLs), in the kale cultivars. In the pale green Half Tall, growth under high light conditions did not induce changes in either pigmentation or total GSL content. In contrast, the purple pigmentation of Black Magic intensified due to increased anthocyanin accumulation. Black Magic showed reduced amounts of indole GSLs and increased amounts of aliphatic GSLs under high light conditions, with notable cultivar-specific adjustments in individual GSL species. Correlation analysis of metabolite profiles suggested cultivar-specific metabolic interplay between serine biosynthesis and the production of indole GSLs. RNA sequencing identified candidate genes encoding metabolic enzymes and regulatory components behind anthocyanin and GSL biosynthesis. These findings improve the understanding of leaf metabolism and its effects on the nutritional quality of kale cultivars.

3.
Molecules ; 29(7)2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38611912

RESUMO

This report demonstrates the first asymmetric synthesis of enantiopure structured triacylglycerols (TAGs) of the ABC type presenting three non-identical fatty acids, two of which are unsaturated. The unsaturated fatty acids included monounsaturated oleic acid (C18:1 n-9) and polyunsaturated linoleic acid (C18:2 n-6). This was accomplished by a six-step chemoenzymatic approach starting from (R)- and (S)-solketals. The highly regioselective immobilized Candida antarctica lipase (CAL-B) played a crucial role in the regiocontrol of the synthesis. The synthesis also benefited from the use of the p-methoxybenzyl (PMB) ether protective group, which enabled the incorporation of two different unsaturated fatty acids into the glycerol skeleton. The total of six such TAGs were prepared, four constituting the unsaturated fatty acids in the sn-1 and sn-2 positions, with a saturated fatty acid in the remaining sn-3 position of the glycerol backbone. In the two remaining TAGs, the different unsaturated fatty acids accommodated the sn-1 and sn-3 end positions, with the saturated fatty acid present in the sn-2 position. Enantiopure TAGs are urgently demanded as standards for the enantiospecific analysis of intact TAGs in fats and oils.


Assuntos
Ácidos Graxos , Glicerol , Éteres , Ácido Linoleico , Triglicerídeos
4.
FEMS Yeast Res ; 232023 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-36494201

RESUMO

The study performed sequential fermentations of red grape juice using several strains of Lachancea thermotolerans and one strain of Saccharomyces cerevisiae. Due to the new conditions imposed by climate change, wine acidity must be affected as well as the volatile profile. Non-Saccharomyces yeasts such as L. thermotolerans are real alternatives to soften the impact of climate change in winemaking. The L. thermotolerans strains included three commercially available strains and two wine-related natural isolates. L. thermotolerans showed significant statistical differences in basic chemical parameters such as lactic acid, malic acid, or ethanol concentrations as well as in the volatile profile. S. cerevisiae clearly produced some volatile compounds in higher amounts than the studied L. thermotolerans strains while others showed the opposite effect. Sequential fermentations involving any of the studied strains of L. thermotolerans with S. cerevisiae showed an increased volatile profile compared to the S. ceresisiae single fermentation, highlighting the synergic effect between the studied species.


Assuntos
Saccharomycetales , Vitis , Vinho , Vinho/análise , Saccharomyces cerevisiae , Fermentação
5.
Crit Rev Food Sci Nutr ; 63(3): 345-377, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-34251918

RESUMO

An increasing demand for natural food preservatives is raised by consumers. For Nordic berry species, abundance of phenolic compounds and potent activities of anti-oxidation and anti-bacteria enables a great potential as food preservatives. This review provides a systematic examination of current literature on phenolic profiles, anti-oxidative and anti-bacterial activities of various extracts of Nordic berry species, as well as the impact of various structure features of phenolics on the bioactivities. Special attention is placed on exploitation of leaves of berry species and pomaces after juice-pressing as side-streams of berry production and processing. The current progress and challenges in application of Nordic berry species as food preservatives are discussed. To fully explore the potential application of Nordic berry species in food industry and especially to valorize the side-streams of berry cultivation (leaves) and juice-pressing industry (pomaces), it is crucial to obtain extracts and fractions with targeted phenolic composition, which have high food preserving efficacy and minimal impact on sensory qualities of food products.


Assuntos
Conservantes de Alimentos , Frutas , Fenóis , Antioxidantes , Conservantes de Alimentos/análise , Frutas/química , Fenóis/análise , Extratos Vegetais/química
6.
Crit Rev Food Sci Nutr ; 62(14): 3798-3816, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-33412908

RESUMO

Sea buckthorn (Hippophaë rhamnoides L., SB), as a multi-functional plant, is widely grown in Asia, Europe and Canada. The berries and leaves of SB contain a diverse array of health-supporting phytochemicals, which are also related to the sensory qualities of berry and berry products. This review summarizes the biologically active key-compounds of the berries and leaves of SB, their health-promoting effects, as well as the contributions to the sensory quality of the berries. The target compounds consist of sugars, sugar derivatives, organic acids, phenolic compounds and lipophilic compounds (mainly carotenoids and tocopherols), which play an important role in anti-inflammatory and antioxidant functions, as well as in metabolic health. In addition, these compounds contribute to the orosensory qualities of SB berries, which are closely related to consumer acceptance and preference of the products. Studies regarding the bioavailability of the compounds and the influence of the processing conditions are also part of this review. Finally, the role of the sensory properties is emphasized in the development of SB products to increase utilization of the berry as a common meal component and to obtain value-added products to support human health.


Assuntos
Hippophae , Cromatografia Líquida de Alta Pressão , Frutas/química , Promoção da Saúde , Hippophae/química , Humanos , Compostos Fitoquímicos/análise , Folhas de Planta/química
7.
Crit Rev Food Sci Nutr ; 62(11): 2942-2962, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-33480261

RESUMO

Fish and algae are the major sources of n-3 polyunsaturated fatty acids (n-3 PUFAs). Globally, there is a rapid increase in demand for n-3 PUFA-rich oils. Conventional oil production processes use high temperature and chemicals, compromising the oil quality and the environment. Hence, alternative green technologies have been investigated for producing oils from aquatic sources. While most of the studies have focused on the oil extraction and enrichment of n-3 PUFAs, less effort has been directed toward green refining of oils from fish and algae. Enzymatic processing and ultrasound-assisted extraction with environment-friendly solvents are the most promising green technologies for extracting fish oil, whereas pressurized extractions are suitable for extracting microalgae oil. Lipase-catalysed ethanolysis of fish and algae oil is a promising green technology for enriching n-3 PUFAs. Green refining technologies such as phospholipase- and membrane-assisted degumming deserve investigation for application in fish and algal oils. In the current review, we critically examined the currently existing research on technologies applied at each of the steps involved in the production of oils rich in n-3 PUFAs from fish and algae species. Special attention was placed on assessment of green technologies in comparison with conventional processing methods.


Assuntos
Ácidos Graxos Ômega-3 , Microalgas , Ácidos Graxos , Ácidos Graxos Insaturados , Óleos de Peixe , Tecnologia
8.
Molecules ; 27(17)2022 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-36080292

RESUMO

Human milk is an intricate, bioactive food promoting infant health. We studied the composition of human milk samples collected over an 8-month lactation using 1H NMR metabolomics. A total of 72 human breast milk samples were collected from ten Chinese mothers at eight different time points. The concentrations of ten human milk oligosaccharides (HMOs), fucose and lactose were quantified. Six of the mothers were classified as Lewis-positive secretors (Se+Le+) and four as Lewis-positive non-secretors (Se-Le+) based on the levels of 2'-fucosyllactose (2'-FL), lacto-N-fucopentaose (LNFP) II, lactodifucotetraose (LDFT) and lacto-N-neotetraose (LNnT). Acetate, citrate, short/medium-chain fatty acids, glutamine and urea showed a time-dependent trend in relation to the stage of lactation. The concentrations of 2'-FL, 3-FL (3-fucosyllactose), 3'-SL (3'-sialyllactose), LDFT, LNFP I, LNFP II, LNFP III, LNnT, LNT (lacto-N-tetraose), and fucose were statistically different between secretors and non-secretors. A temporal difference of approximately 1-2 months between the development of non-secretor and secretor HMO profiles was shown. The results highlighted the importance of long-term breastfeeding, especially among non-secretors.


Assuntos
Aleitamento Materno , Leite Humano , China , Feminino , Fucose/análise , Humanos , Lactente , Lactação , Leite Humano/química , Oligossacarídeos/análise , Espectroscopia de Prótons por Ressonância Magnética
9.
Molecules ; 27(6)2022 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-35335249

RESUMO

Triterpenoids are among the bioactive components of Chaga, the sterile conk of the medicinal fungus Inonotus obliquus. Supercritical fluid extraction of Chaga triterpenoids was carried out with supercritical CO2, while a modified Folch method was used as a comparison. Three temperature-pressure combinations were tested varying between 314-324 K (40-50 °C) and 281-350 bars, using time- and volume-limited extractions. Six triterpenoids were identified with GC-MS and quantified with GC-FID: ergosterol, lanosterol, ß-sitosterol, stigmastanol, betulin, and inotodiol. The Folch extraction resulted in recovery of trametenolic acid, which was not extracted by supercritical CO2. Inotodiol was the major triterpenoid of all the extracts, with a yield of 87-101 mg/100 g and 139 mg/100 g, for SFEs and the Folch method, respectively. The contents of other major triterpenoids, lanosterol and ergosterol, varied in the ranges 59-63 mg/100 g and 17-18 mg/100 g by SFE, respectively. With the Folch method, the yields were 81 mg/100 g and 40 mg/100 g, respectively. The highest recovery of triterpenoids with SFE in relation to Folch was 56% and it was obtained at 324 K (50 °C) and 350 bar, regardless of extraction time or volume of CO2. The recoveries of lanosterol and stigmastanol were unaffected by SFE conditions. Despite the lower yield, SFE showed several advantages including shorter extraction time and less impact on the environment. This work could be a starting point for further studies on green extraction methods of bioactive triterpenoids from Chaga.


Assuntos
Cromatografia com Fluido Supercrítico , Triterpenos , Dióxido de Carbono , Cromatografia com Fluido Supercrítico/métodos , Ergosterol , Inonotus
10.
Rapid Commun Mass Spectrom ; 35(18): e9151, 2021 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-34169571

RESUMO

RATIONALE: Phospholipids are important components of cell membranes that are linked to several beneficial health effects such as increasing plasma HDL cholesterol levels, improving cognitive abilities and inhibiting growth of colon cancer. The role of phospholipid (PL) regioisomers in all these health effects is, however, largely not studied due to lack of analytical methods. METHODS: Electrospray ionization mass spectrometry in negative mode produces structurally informative fragment ions resulting from differential dissociation of fatty acids (FAs) from the sn-1 and sn-2 positions, primarily high-abundance [RCOO]- ions. The fragment ion ratios obtained with different ratios of regiopure phospholipid reference compounds were used to construct calibration curves, which allow determination of regioisomeric ratios of an unknown sample. The method was developed using both direct infusion mass spectrometry (MS) and ultra-high-performance liquid chromatography and hydrophilic interaction liquid chromatography mass spectrometry (UHPLC-HILIC-MS). RESULTS: The produced calibration curves have high coefficients of determination (R2  >0.98) and the fragment ion ratios in replicate analyses were very consistent. A test mixture containing 60/40% ratios of all available regioisomer pairs was analyzed to test and validate the functionality of the calibration curves. The results were accurate and reproducible. However, regioisomeric quantification of certain chromatographically overlapping compounds is restricted by the relatively wide window in precursor ion selection of the MS instrument used. CONCLUSIONS: This method establishes a framework for analysis of phospholipid regioisomers. Specific regioisomers can be quantified using the existing data, and method development will continue with improving chromatographic separation and exploring the fragmentation patterns and efficiencies of different PL classes and FA combinations, ultimately to refine this method for routine analysis of natural fats and oils.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Fosfolipídeos/química , Espectrometria de Massas em Tandem/métodos , Ácidos Graxos/química , Interações Hidrofóbicas e Hidrofílicas , Óleos/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Estereoisomerismo
11.
Compr Rev Food Sci Food Saf ; 20(6): 5570-5615, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34611984

RESUMO

Anthocyanins, the natural red and purple colorants of berries, fruits, vegetables, and tubers, improve carbohydrate metabolism and decrease the risk factors of metabolic disorders, but their industrial use is limited by their chemical instability. Acylation of the glycosyl moieties of anthocyanins, however, changes the chemical properties of anthocyanins and provides enhanced stability. Thus, acylated anthocyanins are more usable as natural colorants and bioactive components of innovative functional foods. Acylated anthocyanins are common in pigmented vegetables and tubers, the consumption of which has the potential to increase the intake of health-promoting anthocyanins as part of the daily diet. For the first time, this review presents the current findings on bioavailability, absorption, metabolism, and health effects of acylated anthocyanins with comparison to more extensively investigated nonacylated anthocyanins. The structural differences between nonacylated and acylated anthocyanins lead to enhanced color stability, altered absorption, bioavailability, in vivo stability, and colonic degradation. The impact of phenolic metabolites and their potential health effects regardless of the low bioavailability of the parent anthocyanins as such is discussed. Here, purple-fleshed potatoes are presented as a globally available, eco-friendly model food rich in acylated anthocyanins, which further highlights the industrial possibilities and nutritional relevance of acylated anthocyanins. This work supports the academic community and industry in food research and development by reviewing the current literature and highlighting gaps of knowledge.


Assuntos
Antocianinas , Frutas , Antocianinas/metabolismo , Disponibilidade Biológica , Metabolismo dos Carboidratos , Frutas/metabolismo , Humanos , Inflamação
12.
Plant Foods Hum Nutr ; 75(2): 184-191, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32009208

RESUMO

The evaluation of the level of alkaloids in edible Lupinus species is crucial from a food safety point of view. Debittering of lupin seeds has a long history; however, the control of the level of alkaloids after processing the seeds is typically only evaluated by changes in the bitter taste. The aim of this study was to evaluate the profile and residual levels of quinolizidine alkaloids (QA) in (Lupinus mutabilis Sweet) after aqueous debittering process. Samples from 10 ecotypes from different areas of Peru were analyzed before and after the process. Based on results obtained by gas chromatography and mass spectrometry, from eight alkaloids identified before the debittering process, only small amounts of lupanine (avg. 0.0012 g/100 g DM) and sparteine (avg. 0.0014 g/100 g DM) remained in the seeds after the debittering process, and no other alkaloids were identified. The aqueous debittering process reduced the content of alkaloids to levels far below the maximal level allowed by international regulations (≤ 0.2 g/kg DM).


Assuntos
Alcaloides , Lupinus , Ecótipo , Cromatografia Gasosa-Espectrometria de Massas , Sementes , Paladar
13.
Anal Chem ; 91(21): 13695-13702, 2019 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-31600055

RESUMO

An ultrahigh-performance-liquid chromatography-electrospray ionization-tandem mass spectrometry (UHPLC-ESI-MS/MS) method was developed for the analysis of AAB and ABC type triacylglycerol (TG) regioisomers. Excellent linear regressions were established between the ratio of [RR]+ product ions and the proportion of regioisomers of TGs. The method was further optimized by analysis of 18 regiospecific pairs of AAB type TGs and five triplets of regioisomers of ABC type TGs with acyl carbon number (ACN) ranging from 36 to 54 and the number of double bonds (DB) from 0 to 7. Reverse linear relationships were recognized between the slope of the calibration curve and the number of double bonds of the sn-2 fatty acids. Negative linear regressions were found between the intercepts of the calibration curves and the sum of ACN + DB of sn-2 fatty acids. The method was highly repeatable as shown by the low deviation and high stability of the calibration curves at different concentrations and between different periods of analysis. This is the first time that calibration curves for the ABC type TGs are reported. The results provide crucial and novel information for reliable and quantitative determination of regioisomeric TGs in natural fats and oils.

14.
Appl Environ Microbiol ; 85(9)2019 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-30824446

RESUMO

Recent studies report the presence of fungal species in breast milk of healthy mothers, suggesting a potential role in infant mycobiome development. In the present work, we aimed to determine whether the healthy human breast milk mycobiota is influenced by geographical location and mode of delivery, as well as to investigate its interaction with bacterial profiles in the same samples. A total of 80 mature breast milk samples from 4 different countries were analyzed by Illumina sequencing of the internal transcribed spacer 1 (ITS1) region, joining the 18S and 5.8S regions of the fungal rRNA region. Basidiomycota and Ascomycota were found to be the dominant phyla, with Malassezia and Davidiella being the most prevalent genera across countries. A core formed by Malassezia, Davidiella, Sistotrema, and Penicillium was shared in the milk samples from the different origins, although specific shifts in mycobiome composition were associated with geographic location and delivery mode. The presence of fungi in the breast milk samples was further confirmed by culture and isolate characterization, and fungal loads were estimated by quantitative PCR (qPCR) targeting the fungal ITS1 region. Cooccurrence network analysis of bacteria and fungi showed complex interactions that were influenced by geographical location, mode of delivery, maternal age, and pregestational body mass index. The presence of a breast milk mycobiome was confirmed in all samples analyzed, regardless of the geographic origin.IMPORTANCE During recent years, human breast milk has been documented as a potential source of bacteria for the newborn. Recently, we have reported the presence of fungi in breast milk from healthy mothers. It is well known that environmental and perinatal factors can affect milk bacteria; however, the impact on milk fungi is still unknown. The current report describes fungal communities (mycobiota) in breast milk samples across different geographic locations and the influence of the mode of delivery. We also provide novel insights on bacterium-fungus interactions, taking into account environmental and perinatal factors. We identified a core of four genera shared across locations, consisting of Malassezia, Davidiella, Sistotrema, and Penicillium, which have been reported to be present in the infant gut. Our data confirm the presence of fungi in breast milk across continents and support the potential role of breast milk in the initial seeding of fungal species in the infant gut.


Assuntos
Fenômenos Fisiológicos Bacterianos , Fungos/isolamento & purificação , Leite Humano/microbiologia , Micobioma , Adulto , China , Feminino , Finlândia , Geografia , Humanos , RNA Fúngico/análise , África do Sul , Espanha
15.
Food Microbiol ; 80: 25-39, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30704594

RESUMO

Bilberry (Vaccinium myrtillus L.) juice was fermented with Torulaspora delbrueckii (TD291 and TD70526) and Schizosaccharomyces pombe (SP3796 and SP70572) in pure fermentation as well as in sequential and simultaneous inoculations with Saccharomyces cerevisiae 1116 (SC1116). Altogether, 56 volatile compounds were identified and semi-quantified with HS-SPME-GC/MS in bilberry products. Yeast fermentation prominently enhanced the aroma complexity of bilberry with a sharp increase in alcohols, esters, aldehydes, and acetals. Compared to S. cerevisiae, T. delbrueckii produced less ethanol but more fusel alcohols that potentially enhance "alcohol" and "nail polish" odors in TD70526 and less "fruity" esters in TD291. SP70572 resulted in high productions of undesirable compounds of acetoin and acetaldehyde but a low content of higher alcohols and esters, SP3796 produced a high content of fatty acid ethyl esters and acetoin. In comparison with monoculture of non-Saccharomyces yeast, sequential and simultaneous cultures of S. pombe and S. cerevisiae significantly decreased the content of acetoin while increased the relative level of esters; sequential cultures of T. delbrueckii and S. cerevisiae remarkably increased the concentration of acetaldehyde; simultaneous inoculations of S. cerevisiae with TD70526 and TD291 significantly decreased the content of fusel alcohols and increased the content of esters, respectively. The findings suggested that non-Saccharomyces yeasts possess the potential to affect and modulate the aromatic profile of fermented bilberry products. Sequential and simultaneous inoculations with S. pombe strains and S. cerevisiae as well as simultaneous fermentation using T. delbrueckii strains and S. cerevisiae are optimal strategies to positively influence the aroma profile of bilberry wines.


Assuntos
Saccharomyces cerevisiae/metabolismo , Schizosaccharomyces/metabolismo , Torulaspora/metabolismo , Vaccinium myrtillus/metabolismo , Compostos Orgânicos Voláteis/análise , Vinho/análise , Antocianinas/metabolismo , Técnicas de Cocultura , Fermentação , Cinética , Extratos Vegetais , Vinho/microbiologia
16.
Molecules ; 24(21)2019 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-31731548

RESUMO

The circular economy is an umbrella concept that applies different mechanisms aiming to minimize waste generation, thus decoupling economic growth from natural resources. Each year, an estimated one-third of all food produced is wasted; this is equivalent to 1.3 billion tons of food, which is worth around US$1 trillion or even $2.6 trillion when social and economic costs are included. In the fruit and vegetable sector, 45% of the total produced amount is lost in the production (post-harvest, processing, and distribution) and consumption chains. Therefore, it is necessary to find new technological and environmentally friendly solutions to utilize fruit wastes as new raw materials to develop and scale up the production of high value-added products and ingredients. Considering that the production and consumption of fruits has increased in the last years and following the need to find the sustainable use of different fruit side streams, this work aimed to describe the chemical composition and bioactivity of different fruit seeds consumed worldwide. A comprehensive focus is given on the extraction techniques of water-soluble and lipophilic compounds and in vitro/in vivo functionalities, and the link between chemical composition and observed activity is holistically explained.


Assuntos
Agricultura/economia , Frutas/química , Compostos Fitoquímicos/química , Sementes/química , Antioxidantes/química , Humanos , Resíduos Industriais/economia
17.
Molecules ; 23(2)2018 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-29373560

RESUMO

Maillard reaction products (MRPs) were prepared from mushroom hydrolysate (MH) by heating with d-xylose and l-cysteine at various temperatures (100 °C-140 °C) for 2 h at a pH of 7.4. The sensory characteristics of MH and MRPs were evaluated by panelists and volatile compounds were analyzed by GC/MS. Additionally, partial least squares regression (PLSR) was performed to analyze the correlation between quantitative sensory characteristics and GC/MS data. GC/MS results revealed that higher reaction temperature resulted in more nitrogen and sulfur containing compounds in MRPs while alcohols, ketones and aldehydes were the major flavor compounds obtained in MH. PLSR results showed that 3-phenylfuran and 2-octylfuran were the compounds responsible for the caramel-like flavor; 1-octen-3-ol, (E)-2-octen-1-ol and geranyl acetone were significantly and positively correlated to mushroom-like flavor, whereas, 2-thiophene-carboxaldehyde, 2,5-thiophenedicarboxaldehyde and 3-methylbutanal positively affected MRPs meat-like attribute. Overall, 125 °C was identified as the optimal temperature for preparing MRPs with abundant volatile compounds and favorable sensory characteristics; the concentration of free amino acids and 5'-GMP, which are associated with the umami taste, in MRPs derived under 125 °C were 3 to 4 times higher than those in MH.


Assuntos
Agaricales/química , Aromatizantes/isolamento & purificação , Odorantes/análise , Percepção Gustatória/fisiologia , Paladar/fisiologia , Adulto , Aldeídos/química , Aldeídos/isolamento & purificação , Cisteína/química , Feminino , Aromatizantes/química , Análise de Alimentos , Furanos/química , Furanos/isolamento & purificação , Cromatografia Gasosa-Espectrometria de Massas , Temperatura Alta , Humanos , Concentração de Íons de Hidrogênio , Hidrólise , Reação de Maillard , Masculino , Pessoa de Meia-Idade , Octanóis/química , Octanóis/isolamento & purificação , Análise de Regressão , Terpenos/química , Terpenos/isolamento & purificação , Tiofenos/química , Tiofenos/isolamento & purificação , Xilose/química
18.
J Chem Ecol ; 43(4): 422-432, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28374224

RESUMO

The evolutionary purpose of a fleshy fruit is to attract seed dispersers and get the seeds dispersed by frugivorous animals. For this reason, fruits should be highly rewarding to these mutualists. However, insect herbivory can alter plant reproductive success e.g. by decreasing fruit yield or affecting the attractiveness of the fruits to mutualistic seed dispersers. Under natural conditions, we tested the effects of experimental larval-defoliation on berry ripening and consumption of a non-cultivated dwarf shrub, the bilberry (Vaccinium myrtillus L.), which produces animal-dispersed berries with high sugar and anthocyanin concentration. Bilberry ramets with high fruit yield were most likely to have their berries foraged, indicating that frugivores made foraging choices based on the abundance of berries. Moreover, the probability for berries being foraged was the lowest for non-defoliated ramets that grew adjacent to larval-defoliated ramets, even though larval-defoliation did not affect the biochemical composition (total concentrations of anthocyanins, sugars and organic acids) or the probability of ripening of berries. We hypothesise that the lower probability for berries being foraged in these ramets may be a consequence of rhizome- or volatile-mediated communication between ramets, resulting in a priming effect of the herbivore defence and lower attractiveness of the non-defoliated ramets.


Assuntos
Antocianinas/análise , Frutas/crescimento & desenvolvimento , Herbivoria , Mariposas/fisiologia , Vaccinium myrtillus/química , Vaccinium myrtillus/fisiologia , Animais , Antocianinas/química , Antocianinas/metabolismo , Cromatografia Gasosa , Cromatografia Líquida de Alta Pressão , Larva/fisiologia , Dispersão de Sementes , Sementes/fisiologia , Vaccinium myrtillus/metabolismo
19.
Ann Nutr Metab ; 70(3): 184-190, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28301837

RESUMO

BACKGROUND/AIMS: The aim of the present study was to identify and quantify the polyamine levels in human milk obtained from different countries and through different modes of delivery, and to investigate their association with breast milk microbes. METHODS: Mature breast milk samples were obtained from 78 healthy mothers after 1 month of lactation from 4 different geographical locations: Finland, Spain (Europe); South Africa (Africa); and China (Asia). Polyamines were determined using HPLC after dansyl derivatization and milk microbiota was obtained by 16S rRNA gene sequencing. RESULTS: The mean values of polyamines in breast milk were 70.0, 424.2, and 610.0 nmol/dL for putrescine, spermidine and spermine, respectively, and 1,170.9 nmol/dL of total polyamines. The levels of putrescine were significantly higher in Spain (p < 0.05) and spermidine levels were significantly higher in Finland (p < 0.05) compared with other countries. Cesarean delivery had an impact on polyamine levels and it was related to an increase in the putrescine concentration being significant in Spanish samples (p < 0.01). Furthermore, putrescine levels were correlated positively with Gammaproteobacteria (r = 0.46, p < 0.001), especially with Pseudomonas fragi (r = 0.40, p < 0.001). CONCLUSIONS: The results demonstrate significant effect of geographical variations in human milk polyamine concentrations, being correlated with human milk microbiota composition. These differences may have an impact on infant development during lactation.


Assuntos
Parto Obstétrico/métodos , Leite Humano/química , Leite Humano/microbiologia , Poliaminas/análise , Adulto , China , Feminino , Finlândia , Voluntários Saudáveis , Humanos , Masculino , Microbiota , África do Sul , Espanha
20.
Perception ; 46(3-4): 352-365, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-27687812

RESUMO

Our aim was to explore factors potentially associated with subjective (self-rated) and objective (measured using the Sniffin' Sticks Extended test) olfactory performance in the general population without olfactory disorders. We studied associations between olfactory performance and how important odors were in determining liking for new places, things, and people (measured using the Affective Impact of Odor scale) and the average annoyance caused by odors in 117 adults (83 women, 34 men; age 18-69 years, mean age 32 years). In a subset of 44 participants, we also studied associations between olfactory performance and spice odor identification task scores (14 odors) and the number of herbs and spices consumed. Self-rated olfactory acuity and odor-related annoyance were associated with the Affective Impact of Odor scores, but neither correlated with the smell test results. Instead, the number of spices consumed correlated with spice odor identification score ( r = .50) and the identification (but not threshold nor discrimination) subscore of the Sniffin' Sticks test ( r = .49). Our results suggest that a tendency to perceive odors in affective terms may be associated with overestimation of olfactory abilities and that recurrent exposure to a large variety of spice odors may improve performance on odor identification.


Assuntos
Afeto , Odorantes , Percepção Olfatória , Autorrelato , Adolescente , Adulto , Idoso , Discriminação Psicológica , Retroalimentação Psicológica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reconhecimento Psicológico , Limiar Sensorial , Especiarias , Adulto Jovem
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