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1.
Proc Natl Acad Sci U S A ; 117(30): 17599-17606, 2020 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-32647063

RESUMO

Fossilized carotenoid hydrocarbons provide a window into the physiology and biochemistry of ancient microbial phototrophic communities for which only a sparse and incomplete fossil record exists. However, accurate interpretation of carotenoid-derived biomarkers requires detailed knowledge of the carotenoid inventories of contemporary phototrophs and their physiologies. Here we report two distinct patterns of fossilized C40 diaromatic carotenoids. Phanerozoic marine settings show distributions of diaromatic hydrocarbons dominated by isorenieratane, a biomarker derived from low-light-adapted phototrophic green sulfur bacteria. In contrast, isorenieratane is only a minor constituent within Neoproterozoic marine sediments and Phanerozoic lacustrine paleoenvironments, for which the major compounds detected are renierapurpurane and renieratane, together with some novel C39 and C38 carotenoid degradation products. This latter pattern can be traced to cyanobacteria as shown by analyses of cultured taxa and laboratory simulations of sedimentary diagenesis. The cyanobacterial carotenoid synechoxanthin, and its immediate biosynthetic precursors, contain thermally labile, aromatic carboxylic-acid functional groups, which upon hydrogenation and mild heating yield mixtures of products that closely resemble those found in the Proterozoic fossil record. The Neoproterozoic-Phanerozoic transition in fossil carotenoid patterns likely reflects a step change in the surface sulfur inventory that afforded opportunities for the expansion of phototropic sulfur bacteria in marine ecosystems. Furthermore, this expansion might have also coincided with a major change in physiology. One possibility is that the green sulfur bacteria developed the capacity to oxidize sulfide fully to sulfate, an innovation which would have significantly increased their capacity for photosynthetic carbon fixation.


Assuntos
Cianobactérias/fisiologia , Fotossíntese , Enxofre/metabolismo , Carotenoides/química , Carotenoides/metabolismo , Cromatografia Líquida , Cromatografia Gasosa-Espectrometria de Massas , Espectrometria de Massas , Fotossíntese/genética , Pigmentos Biológicos/química , Pigmentos Biológicos/metabolismo
2.
Int J Syst Evol Microbiol ; 70(7): 4305-4314, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32579104

RESUMO

A new member of the family Flavobacteriaceae was isolated from the biofilm of a stone at Nordstrand, a peninsula at the German North Sea shore. Phylogenetic analysis of the 16S rRNA gene sequence showed that strain ANORD1T was most closely related to the validly described type strains Polaribacter porphyrae LNM-20T (97.0 %) and Polaribacter reichenbachii KMM 6386T (96.9 % 16S rRNA gene sequence similarity) and clustered with Polaribacter gangjinensis K17-16T (96.0 %). Strain ANORD1T was determined to be mesophilic, Gram-negative, non-motile and strictly aerobic. Optimal growth was observed at 20-30 °C, within a salinity range of 2-7 % sea salt and from pH 7-10. Like other type strains of the genus Polaribacter, ANORD1T was tested negative for flexirubin-type pigments, while carotenoid-type pigments were detected. The DNA G+C content of strain ANORD1T was 30.6 mol%. The sole respiratory quinone detected was menaquinone 6 (MK-6). The major fatty acids identified were C15 : 0, iso-C15 : 0, C15 : 1 ω6c and iso-C15 : 0 3-OH. Based on the polyphasic approach, strain ANORD1T represents a novel species in the genus Polaribacter, with the name Polaribacter septentrionalilitoris sp. nov. being proposed. The type strain is ANORD1T (=DSM 110039T=NCIMB 15081T=MTCC 12685T).


Assuntos
Biofilmes , Flavobacteriaceae/classificação , Filogenia , Técnicas de Tipagem Bacteriana , Composição de Bases , Carotenoides/química , DNA Bacteriano/genética , Ácidos Graxos/química , Flavobacteriaceae/isolamento & purificação , Mar do Norte , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
3.
Food Chem ; 326: 126974, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32413759

RESUMO

In this study, flaxseeds roasted at microwave (MW) powers of 180, 360 and 540 W for 5 and 10 min were evaluated for their influence on oil yield, chemical properties, carotenoid and chlorophyll contents, total phenolic content (TPC), radical scavenging activity (RSA), oxidative stability index (OSI), fatty acid composition and Maillard reaction products (MRPs). MW roasting at 540 W for 10 min significantly increased the oil yield, TPC, OSI, RSA, a* value, browning index, carotenoid and chlorophyll contents while decreased the L* and b* values of flaxseed oil (FSO). MRPs were detected only in oil of flaxseeds roasted at 540 W for 10 min. The level of stearic, palmitic, oleic, linoleic and α-linolenic acids were slightly changed and FTIR spectra showed minor variation in peak intensities of oils from different MW roasted flaxseeds. MW roasting (540 W for 10 min) is recommended for improving quality and stability characteristics of FSO.


Assuntos
Ácidos Graxos/análise , Linho/química , Óleo de Semente do Linho/química , Micro-Ondas , Antioxidantes/química , Carotenoides/análise , Carotenoides/química , Clorofila/análise , Clorofila/química , Ácidos Graxos/química , Armazenamento de Alimentos , Produtos Finais de Glicação Avançada/análise , Produtos Finais de Glicação Avançada/química , Oxirredução , Fenóis/análise , Fenóis/química , Sementes/química , Espectroscopia de Infravermelho com Transformada de Fourier
4.
Medicine (Baltimore) ; 99(16): e19772, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32311984

RESUMO

BACKGROUND: Carotenoids play essential roles in human health, such as antioxidant activity, and therefore can decrease free radicals oxidation action, preventing numerous diseases. However, these compounds have an unstable nature, turning them susceptible to adverse conditions in food processing and storage. Thereby the search for alternatives that maintain and enhance carotenoid antioxidant function, such as encapsulation, has grown. The objective of this study was to establish a systematic review protocol to evaluate the effect of different encapsulation techniques on the antioxidant action of carotenoids, evaluating which one is the best and safest, and their role in enhancing the antioxidant activity. METHODS: This protocol was guided by the preferred reporting items for protocols for systematic reviews and meta-analyzes. The databases to be searched are PubMed, EMBASE, Scopus, ScienceDirect, and Web of Science. Experimental studies conducted in rats and mice (in vivo) of both sexes and ages, evaluating the use of encapsulated and crude carotenoids will be included in the systematic review. The characteristics of the studies, the experimental model, and the main results will be described, and the risk of bias assessment will be evaluated. Three independent reviewers will proceed with the selection of studies, data extraction, and methodological quality assessment. A narrative synthesis will be made for the included studies. Besides, if sufficient qualitative data is available, a meta-analysis will be conducted. I2 statistics will be used to assess heterogeneity. RESULTS: This protocol will guide the production of a systematic review that can determine the effect of different encapsulation techniques and encapsulating agents on the antioxidant action of carotenoids. Thus, it will enable the determination of the best encapsulation techniques to promote the preservation and increase of the antioxidant activity, contributing to future research that may reproduce the best carotenoid encapsulation technique in an animal model. CONCLUSION: The systematic review to be produced from this protocol will provide support for the construction of research that evaluates the effect of encapsulation on the antioxidant function of carotenoids and its possible application as a nutraceutical, considering that this functionality is directly associated with health promotion. RECORD OF SYSTEMATIC REVIEW: This review was recorded in the International Register of Prospective Systematic Reviews on January 22, 2020 (registration: CRD42020142065). Available at: https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42020142065.


Assuntos
Antioxidantes/administração & dosagem , Carotenoides/administração & dosagem , Animais , Antioxidantes/análise , Cápsulas , Carotenoides/química , Humanos , Revisões Sistemáticas como Assunto
5.
Proc Natl Acad Sci U S A ; 117(12): 6502-6508, 2020 03 24.
Artigo em Inglês | MEDLINE | ID: mdl-32139606

RESUMO

Carotenoids play a number of important roles in photosynthesis, primarily providing light-harvesting and photoprotective energy dissipation functions within pigment-protein complexes. The carbon-carbon double bond (C=C) conjugation length of carotenoids (N), generally between 9 and 15, determines the carotenoid-to-(bacterio)chlorophyll [(B)Chl] energy transfer efficiency. Here we purified and spectroscopically characterized light-harvesting complex 2 (LH2) from Rhodobacter sphaeroides containing the N = 7 carotenoid zeta (ζ)-carotene, not previously incorporated within a natural antenna complex. Transient absorption and time-resolved fluorescence show that, relative to the lifetime of the S1 state of ζ-carotene in solvent, the lifetime decreases ∼250-fold when ζ-carotene is incorporated within LH2, due to transfer of excitation energy to the B800 and B850 BChls a These measurements show that energy transfer proceeds with an efficiency of ∼100%, primarily via the S1 → Qx route because the S1 → S0 fluorescence emission of ζ-carotene overlaps almost perfectly with the Qx absorption band of the BChls. However, transient absorption measurements performed on microsecond timescales reveal that, unlike the native N ≥ 9 carotenoids normally utilized in light-harvesting complexes, ζ-carotene does not quench excited triplet states of BChl a, likely due to elevation of the ζ-carotene triplet energy state above that of BChl a These findings provide insights into the coevolution of photosynthetic pigments and pigment-protein complexes. We propose that the N ≥ 9 carotenoids found in light-harvesting antenna complexes represent a vital compromise that retains an acceptable level of energy transfer from carotenoids to (B)Chls while allowing acquisition of a new, essential function, namely, photoprotective quenching of harmful (B)Chl triplets.


Assuntos
Proteínas de Bactérias/metabolismo , Bacterioclorofilas/metabolismo , Carotenoides/metabolismo , Complexos de Proteínas Captadores de Luz/metabolismo , Proteínas de Bactérias/química , Carotenoides/química , Transferência de Energia , Cinética , Complexos de Proteínas Captadores de Luz/química , Fotossíntese , Rhodobacter sphaeroides/química , Rhodobacter sphaeroides/metabolismo
6.
J Food Sci ; 85(4): 1160-1166, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32125697

RESUMO

The effect of chemical refining process on the bioactive composition, in vitro antioxidant capacity, and their correlation of perilla seed oil (PSO) were investigated. In this paper, seven samples corresponding to each step of the refining process (degumming, neutralization, bleaching, deodorization, winterization, crude, and refined oils) were studied. The results showed that phenolic compounds and tocopherols were removed from PSO to a degree of 19.4% and 5.4%, respectively. In addition, the carotenoid content of PSO decreased during the refining process. The main carotenoid of PSO was found to be lutein, and the compound was lost completely during the bleaching step of the refining process. In this paper, we analyzed the variation of carotenoid content in PSO during the refining process for the first time. Neutralization affected the contents of phytosterols the most, followed by the effects of degumming and bleaching. The demonstrated results of Pearson product-moment correlation indicated that total tocopherols were significantly correlated with the 2,2-diphenyl-1-picrylhydrazyl (DPPH) and oxygen radical absorption capacity (ORAC) values, whereas carotenoids were significantly correlated with the DPPH value. However, phenolic compounds and phytosterols have no significant difference with DPPH, 2,2'-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt, ORAC, and ferric reducing antioxidant power values. The collected information can be applied to seeking out optimum factors needed to suffice the fundamental requirements for PSO production and minimize micronutrient losses to enhance its market value. PRACTICAL APPLICATION: The present study aimed to determine influence of chemical refining in the bioactive composition of perilla seed oil (PSO) as well as its antioxidant capacity in vitro. Moreover, we also intend to find the correlation between them. Results indicated that this study supplies a good reference for the industrial parameters of the refining process to minimize micronutrient losses and further obtain high-quality PSO products for consumers.


Assuntos
Antioxidantes/química , Manipulação de Alimentos/métodos , Perilla/química , Ácido alfa-Linoleico/química , Carotenoides/química , Micronutrientes/química , Fenóis/análise , Fitosteróis/química , Óleos Vegetais/química , Sementes/química , Tocoferóis/química
7.
Nat Commun ; 11(1): 1542, 2020 03 24.
Artigo em Inglês | MEDLINE | ID: mdl-32210238

RESUMO

Natural photosynthesis can be divided between the chlorophyll-containing plants, algae and cyanobacteria that make up the oxygenic phototrophs and a diversity of bacteriochlorophyll-containing bacteria that make up the anoxygenic phototrophs. Photosynthetic light harvesting and reaction centre proteins from both kingdoms have been exploited for solar energy conversion, solar fuel synthesis and sensing technologies, but the energy harvesting abilities of these devices are limited by each protein's individual palette of pigments. In this work we demonstrate a range of genetically-encoded, self-assembling photosystems in which recombinant plant light harvesting complexes are covalently locked with reaction centres from a purple photosynthetic bacterium, producing macromolecular chimeras that display mechanisms of polychromatic solar energy harvesting and conversion. Our findings illustrate the power of a synthetic biology approach in which bottom-up construction of photosystems using naturally diverse but mechanistically complementary components can be achieved in a predictable fashion through the encoding of adaptable, plug-and-play covalent interfaces.


Assuntos
Proteínas de Arabidopsis/química , Proteínas de Bactérias/química , Bacterioclorofilas/química , Complexos de Proteínas Captadores de Luz/química , Energia Solar , Biologia Sintética/métodos , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/efeitos da radiação , Proteínas de Bactérias/genética , Proteínas de Bactérias/efeitos da radiação , Bacterioclorofilas/genética , Bacterioclorofilas/efeitos da radiação , Carotenoides/química , Carotenoides/efeitos da radiação , Complexos de Proteínas Captadores de Luz/genética , Complexos de Proteínas Captadores de Luz/efeitos da radiação , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/efeitos da radiação , Rhodobacter sphaeroides/química , Rhodobacter sphaeroides/genética , Rhodobacter sphaeroides/efeitos da radiação , Luz Solar
8.
BMC Complement Med Ther ; 20(1): 29, 2020 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-32020873

RESUMO

BACKGROUND: Crocetin is a major active component of saffron, which has a wide range of pharmacological effects. However, due to its low solubility, the pharmacological effects of crocetin cannot be better utilized. METHODS: In this study, we modified the chemical structure of crocetin by conjugating with ethylamine and 4-Fluorbenzylamine to enhance its solubility and biological activities. The solubility and the influence of synthesized derivatives on the proliferation of tumor cells and the inflammatory effect of macrophage were investigated. RESULTS: It was shown that, compared with the crocetin, the synthesized derivatives have much higher solubility. Moreover, the inhibitory effect of the derivatives on varieties of tumor cells, including human ovarian carcinoma cell line, human lung cancer cell line, rat melanoma cell line was enhanced after the modification. Besides that, the derivatives were improved for the anti-inflammatory efficacy with the cytotoxicity decreased. CONCLUSIONS: The synthesized derivatives were shown for their good solubility and the great potential in tumor and inflammation treatment.


Assuntos
Anti-Inflamatórios/farmacologia , Carotenoides/química , Carotenoides/farmacologia , Proliferação de Células/efeitos dos fármacos , Macrófagos/metabolismo , Animais , Linhagem Celular Tumoral , Crocus , Humanos , Camundongos , Ratos
9.
Food Chem ; 315: 126292, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32035314

RESUMO

Using isotopic ratio mass spectrometry (IRMS) measurements, this study analyzed samples of saffron originating from two distinct geographical regions. We then used the results to distinguish saffron of the two considered origins. δ13C data related to the crocin fractions in 48 saffron samples from Western Macedonia (Greece) and 48 samples from Khorasan Province (Iran) were correlated to an index derived from triacylglycerols. Isotopic data could clearly differentiate between samples from the two areas. The isotopic measurements were -28.3 to -26.9 for Greek samples, and -26.1 to -24.5 for Iranian samples. Another index, derived from a gas-chromatographic analysis of the triacylglycerols, successfully determined that the range of isotopic values that characterized Greek samples was 52% larger than the range that characterized Iranian samples. The application of statistical evaluations permitted us to identify the two groups of saffron with confidence and to accurately identify the site of origin of a saffron sample.


Assuntos
Crocus/química , Triglicerídeos/química , Isótopos de Carbono , Carotenoides/química , Cromatografia Gasosa-Espectrometria de Massas , Grécia , Irã (Geográfico) , Espectrometria de Massas , Extratos Vegetais/química , Água/química
10.
Food Chem ; 315: 126275, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32004982

RESUMO

The effects of individual epi-brassinolide (eBL) and NaCl, as well as their combination on contents of main phytochemicals and antioxidant capacity of Chinese kale sprouts were investigated. Our results showed that the application of 100 nM eBL decreased the contents of individual and total glucosinolates, while treatments of 160 mM NaCl both alone and combined with 100 nM eBL enhanced the glucosinolates accumulation by promoting the expression of genes involved in glucosinolate biosynthesis in Chinese kale sprouts and the combined treatment led to significantly higher content of most glucosinolate profiles. Moreover, it also elevated the contents of ascorbic acid and total carotenoids, whereas did not influence the total phenolics and antioxidant capacity. These findings indicated that the combined treatment of 100 nM eBL plus 160 mM NaCl could provide a new strategy to improve the main health promoting compounds in Chinese kale sprouts.


Assuntos
Brassica/química , Brassinosteroides/química , Compostos Fitoquímicos/química , Plântula/química , Cloreto de Sódio/química , Esteroides Heterocíclicos/química , Antioxidantes/química , Ácido Ascórbico/química , Carotenoides/química , Glucosinolatos/química , Fenóis/química , Cloreto de Sódio/farmacologia
11.
J Agric Food Chem ; 68(10): 3228-3237, 2020 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-32074447

RESUMO

Effects of natural catalysts, isothiocyanates and polysulfides, on Z-isomerization and decomposition of (all-E)-carotenoids (lycopene, ß-carotene, and astaxanthin) after heat treatment were investigated. When isothiocyanates were added to (all-E)-carotenoid solutions and heated, Z-isomerization and decomposition of carotenoids were enhanced and the degree differed depending on the isothiocyanate type. Interestingly, when polysulfides were applied in the same manner, in addition to promoting the Z-isomerization reaction, they markedly improved the thermal stability of carotenoids. Successively, we investigated the reaction characteristics of allyl isothiocyanate (AITC) and diallyl disulfide (DADS) using (all-E)-lycopene; that is, effects of the amount added, solvent used, and reaction temperature and time, as well as the combination use on Z-isomerization and decomposition of lycopene, were investigated. With increases in the amount added and reaction temperature and time, Z-isomerization of lycopene was promoted for both catalysts. The high-temperature treatment tests clearly showed that AITC induced thermal decomposition of lycopene, whereas DADS improved the lycopene stability. Moreover, the simultaneous use of AITC and DADS resulted in a synergetic effect on the Z-isomerization efficiency.


Assuntos
Carotenoides/química , Isotiocianatos/química , Sulfetos/química , Catálise , Isomerismo , Licopeno/química , Xantofilas/química , beta Caroteno/química
12.
Nat Commun ; 11(1): 662, 2020 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-32005811

RESUMO

The photosynthetic apparatus of higher plants can dissipate excess excitation energy during high light exposure, by deactivating excited chlorophylls through a mechanism called nonphotochemical quenching (NPQ). However, the precise molecular details of quenching and the mechanism regulating the quenching level are still not completely understood. Focusing on the major light-harvesting complex LHCII of Photosystem II, we show that a charge transfer state involving Lutein can efficiently quench chlorophyll excitation, and reduce the excitation lifetime of LHCII to the levels measured in the deeply quenched LHCII aggregates. Through a combination of molecular dynamics simulations, multiscale quantum chemical calculations, and kinetic modeling, we demonstrate that the quenching level can be finely tuned by the protein, by regulating the energy of the charge transfer state. Our results suggest that a limited conformational rearrangement of the protein scaffold could act as a molecular switch to activate or deactivate the quenching mechanism.


Assuntos
Carotenoides/metabolismo , Clorofila/metabolismo , Plantas/metabolismo , Carotenoides/química , Clorofila/química , Transporte de Elétrons , Cinética , Luz , Complexos de Proteínas Captadores de Luz/química , Complexos de Proteínas Captadores de Luz/metabolismo , Fotossíntese , Complexo de Proteína do Fotossistema II/química , Complexo de Proteína do Fotossistema II/metabolismo , Plantas/química , Plantas/efeitos da radiação
13.
Nat Commun ; 11(1): 610, 2020 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-32001694

RESUMO

NAD(P)H dehydrogenase-like (NDH) complex NDH-1L of cyanobacteria plays a crucial role in cyclic electron flow (CEF) around photosystem I and respiration processes. NDH-1L couples the electron transport from ferredoxin (Fd) to plastoquinone (PQ) and proton pumping from cytoplasm to the lumen that drives the ATP production. NDH-1L-dependent CEF increases the ATP/NADPH ratio, and is therefore pivotal for oxygenic phototrophs to function under stress. Here we report two structures of NDH-1L from Thermosynechococcus elongatus BP-1, in complex with one Fd and an endogenous PQ, respectively. Our structures represent the complete model of cyanobacterial NDH-1L, revealing the binding manner of NDH-1L with Fd and PQ, as well as the structural elements crucial for proper functioning of the NDH-1L complex. Together, our data provides deep insights into the electron transport from Fd to PQ, and its coupling with proton translocation in NDH-1L.


Assuntos
Complexo I de Transporte de Elétrons/química , NADPH Desidrogenase/química , Fotossíntese , Thermus/enzimologia , Sítios de Ligação , Carotenoides/química , Membrana Celular/química , Transporte de Elétrons , Complexo I de Transporte de Elétrons/ultraestrutura , Ferredoxinas/química , Ferredoxinas/metabolismo , Interações Hidrofóbicas e Hidrofílicas , Lipídeos/química , Modelos Moleculares , NADPH Desidrogenase/ultraestrutura , Plastoquinona/química , Plastoquinona/metabolismo , Domínios Proteicos , Subunidades Proteicas/química , Homologia Estrutural de Proteína
14.
BMC Bioinformatics ; 21(1): 1, 2020 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-31898485

RESUMO

BACKGROUND: The green microalga Dunaliella salina accumulates a high proportion of ß-carotene during abiotic stress conditions. To better understand the intracellular flux distribution leading to carotenoid accumulation, this work aimed at reconstructing a carbon core metabolic network for D. salina CCAP 19/18 based on the recently published nuclear genome and its validation with experimental observations and literature data. RESULTS: The reconstruction resulted in a network model with 221 reactions and 212 metabolites within three compartments: cytosol, chloroplast and mitochondrion. The network was implemented in the MATLAB toolbox CellNetAnalyzer and checked for feasibility. Furthermore, a flux balance analysis was carried out for different light and nutrient uptake rates. The comparison of the experimental knowledge with the model prediction revealed that the results of the stoichiometric network analysis are plausible and in good agreement with the observed behavior. Accordingly, our model provides an excellent tool for investigating the carbon core metabolism of D. salina. CONCLUSIONS: The reconstructed metabolic network of D. salina presented in this work is able to predict the biological behavior under light and nutrient stress and will lead to an improved process understanding for the optimized production of high-value products in microalgae.


Assuntos
Carbono/metabolismo , Clorófitas/metabolismo , Microalgas/metabolismo , Carbono/química , Carotenoides/química , Carotenoides/metabolismo , Clorófitas/química , Clorófitas/efeitos da radiação , Cloroplastos/química , Cloroplastos/metabolismo , Citosol/química , Citosol/metabolismo , Luz , Redes e Vias Metabólicas , Microalgas/química , Microalgas/efeitos da radiação , Mitocôndrias/química , Mitocôndrias/metabolismo , Modelos Biológicos , Estresse Fisiológico
15.
Food Chem ; 313: 126065, 2020 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-31935663

RESUMO

Brassica spp. are excellent sources of bioactive compounds. These vegetables are usually processed in the home, or by catering and food service industries, on the basis of convenience and taste preference. Shelf-life of these seasonal, perishable vegetables can be extended by preservation methods (e.g. freezing and canning), which usually involve blanching. Cooking, blanching, freezing and canning alter the physical and chemical characteristics of Brassica, and only some of the changes are desirable. We have reviewed the results of a large number of studies that assessed the effects of different treatments and storage conditions on various quality parameters in Brassica. These effects are important in relation to nutritional value, health benefits and attractiveness of the vegetables. The findings vary considerably for each bioactive component, depending on the treatments, conditions and matrices. Optimization of processing and storage conditions is, therefore, important to maximize the intake of beneficial compounds contained in Brassica spp.


Assuntos
Brassica/química , Culinária/métodos , Antioxidantes/química , Ácido Ascórbico/química , Brassica/metabolismo , Carotenoides/química , Congelamento , Humanos , Valor Nutritivo , Fenóis/química , Paladar
16.
Anal Bioanal Chem ; 412(6): 1335-1342, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31900534

RESUMO

The presence of carotenoids in human colostrum has been reported in the literature, and xanthophyll esters in human colostrum were recently detected for the first time. However, no published studies have reported whether apocarotenoids, which are metabolites derived from carotenoid enzymatic or nonenzymatic oxidative cleavage, are present in human colostrum. Therefore, the purpose of the present study was to search for the possible occurrence of apocarotenoids, including apocarotenoid esters, in human colostrum for the first time by applying an online supercritical fluid extraction-supercritical fluid chromatography-tandem mass spectrometry methodology. Recent evidence related to apocarotenoid transcriptional activity has suggested that they may have beneficial health properties superior to those of their parent carotenoids. Three different apocarotenoids, namely apo-8'-ß-carotenal, apo-8'-lycopenal, and ß-citraurin, were identified in intact human colostrum samples, with average concentrations of 85 nmol L-1, 54.6 nmol L-1, and 75.4 nmol L-1, respectively. The overall detection of 16 different free apocarotenoids and 10 different apocarotenoid fatty acid esters in human colostrum was achieved here for the first time. Their occurrence in human colostrum certainly has implications for newborn health status, since colostrum is the only form of food for the newborn during the very first days of life. Graphical abstract.


Assuntos
Carotenoides/análise , Colostro/química , Carotenoides/química , Cromatografia com Fluido Supercrítico/métodos , Ésteres , Feminino , Humanos , Limite de Detecção , Reprodutibilidade dos Testes , Extração em Fase Sólida/métodos , Espectrometria de Massas em Tandem/métodos
17.
Int J Syst Evol Microbiol ; 70(1): 662-667, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31661050

RESUMO

A Gram-stain-negative, motile, alkali-tolerant, swollen-rod shaped, reddish brown coloured, phototrophic bacterium designated as strain JA980T, was isolated from freshwater sampled at Umiam lake, Shillong, India. Strain JA980T grew well up to pH 9.0. Respiratory quinones were ubiquinone 10 and rhodoquinone 10. The major fatty acid was C18: 1ω7c/C18:1ω6c with minor amounts of C18:0, C16:0, C18:0 3-OH and C16:0 3-OH. Strain JA980T contained bacteriochlorophyll-a and carotenoids of the spirilloxanthin series. The polar lipids of strain JA980T comprised phosphatidylethanolamine, phosphatidylcholine, diphosphatidylglycerol, an unidentified phospholipid, unidentified amino lipids (AL1,3,4,5) and an unidentified lipid (L1). Strain JA980T had the highest (99.57 %) 16S rRNA gene sequence similarity to the type strains of Rhodomicrobium vannielii ATCC17100T and Rhodomicrobium udaipurense JA643T. The genome of strain JA980T was 3.88 Mbp with a DNA G+C content of 62.4 mol%. Based on the results of phylogenetic analyses, low in silico DNA-DNA hybridization values (33 %), low (87 %) average nucleotide identity results, chemotaxonomic characteristics and differential physiological properties, strain JA980T could not be classified into either of the two recognized species of the genus Rhodomicrobium, suggesting that it represents a novel species, for which the name Rhodomicrobium lacus sp. nov. is proposed. The type strain is JA980T (=KCTC 15697T= MCC 3714T= NBRC 113803T).


Assuntos
Lagos/microbiologia , Filogenia , Rhodomicrobium/classificação , Técnicas de Tipagem Bacteriana , Bacterioclorofila A/química , Composição de Bases , Carotenoides/química , DNA Bacteriano/genética , Ácidos Graxos/química , Índia , Hibridização de Ácido Nucleico , Fosfolipídeos/química , Pigmentação , RNA Ribossômico 16S/genética , Rhodomicrobium/isolamento & purificação , Análise de Sequência de DNA , Ubiquinona/análogos & derivados , Ubiquinona/química , Microbiologia da Água
18.
Int J Syst Evol Microbiol ; 70(2): 1192-1202, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31769750

RESUMO

A novel aerobic moderately thermophilic bacterium, strain 3753OT, was isolated from a Chukotka hot spring (Arctic, Russia) using the newly developed technology of laser engineering of microbial systems. Сells were regular short rods, 0.4×0.8-2.0 µm in size, with a monoderm-type envelope and a single flagellum. The temperature and pH ranges for growth were 42-60 °C and pH 6.5-8.5, the optima being 50-54 °C and pH 7.3. Strain 3753OT grew chemoorganoheterotrophically on a number of carbohydrates or peptidic substrates and volatile fatty acids, and chemolithoautotrophically with siderite (FeCO3) as the electron donor. The major cellular fatty acid was branched C19 : 0. Phosphatidylethanolamine, phosphatidylglycerol and two unidentified phospholipids as well as two yellow carotenoid-type pigments were detected in the polar lipid extract. Strain 3753OT was inhibited by chloramphenicol, polymyxin B, vancomycin, streptomycin, neomycin and kanamycin, but resistant to the action of novobiocin and ampicillin. The DNA G+C content was 69.9 mol%. The 16S rRNA gene as well as 51 conservative protein sequence-based phylogenetic analyses placed strain 3753OT within the previously uncultivated lineage OLB14 in the phylum Chloroflexi. Taking into account the phylogenetic position as well as phenotypic properties of the novel isolate, the novel genus and species Tepidiforma bonchosmolovskayae gen. nov., sp. nov., within the Tepidiformaceae fam. nov., the Tepidiformales ord. nov. and the Tepidiformia classis nov. are proposed. The type strain of Tepidiforma bonchosmolovskayae is 3753OT (=VKM B-3389T=KTCT 72284T).


Assuntos
Chloroflexi/classificação , Fontes Termais/microbiologia , Filogenia , Regiões Árticas , Técnicas de Tipagem Bacteriana , Composição de Bases , Carotenoides/química , DNA Bacteriano/genética , Ácidos Graxos/química , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Federação Russa , Análise de Sequência de DNA
19.
J Sci Food Agric ; 100(4): 1662-1670, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31808163

RESUMO

BACKGROUND: Tomatoes are an important source of human health-promoting compounds, and efforts have been made to enhance their nutritional quality through conventional plant breeding or biotechnology. This study assessed the composition of volatile compounds, phenolics and carotenoids in two allele-introgressed tomato lines, an anthocyanin-rich purple tomato and a ß-carotene-rich orange tomato, as well as a red tomato. RESULTS: The purple tomato peel accumulated a high amount of anthocyanins, mainly petunidin 3-(p-coumaroyl)-rutinoside-5-glucoside, responsible for the purple color, and other flavonoids such as rutin and kaempferol. The orange tomato did not undergo changes in the flavonoid profile but accumulated a high amount of ß-carotene, with impairment on lycopene. A total of 27 volatile compounds were detected in purple tomato, 38 in orange tomato and 39 in red tomato. They comprise terpenes, carbonyls, alcohols, esters and hydrocarbons. The difference in the volatile compound profiles of ripe fruits can be related to differences in some precursor contents in the introgression lines. Orange tomato accumulates volatiles from ß-carotene cleavage, not detected in the red fruits. Otherwise, volatiles from lycopene were absent in orange tomato as a result of the inhibition on lycopene accumulation. Phenolic volatiles were higher in the purple tomato, which has the highest total phenolic content. CONCLUSION: The introgessed alleles seem to have a positive effect on the enrichment of ripe tomato in bioactive compounds such as anthocyanins and ß-carotene, improving nutritional quality. However, the allele introgression resulted in marked changes in volatile compound profiles, whose impact on tomato flavor and consumer acceptability needs to be evaluated. © 2019 Society of Chemical Industry.


Assuntos
Carotenoides/química , Flavonoides/química , Frutas/química , Lycopersicon esculentum/genética , Compostos Orgânicos Voláteis/química , Alelos , Carotenoides/metabolismo , Cor , Flavonoides/metabolismo , Frutas/genética , Frutas/metabolismo , Lycopersicon esculentum/química , Lycopersicon esculentum/metabolismo , Valor Nutritivo , Compostos Orgânicos Voláteis/metabolismo
20.
Artigo em Inglês | MEDLINE | ID: mdl-31835164

RESUMO

In this research, a new magnetic sorbent material composed of three-dimensional graphene aerogel decorated with Fe3O4 nanoparticles attached to hollow sporopollenin exine capsules was synthesized and applied for extraction of vitamin D3 before HPLC-UV analysis. The adsorbent was characterized by FT-IR, SEM, VSM, and zeta potential techniques. The important parameters of the extraction process, including adsorbent dosage, desorption conditions, adsorption time, pH, and salt concentration, were investigated. Under the optimized condition, the method analytical figures of merit were evaluated as follows: linear dynamic range, 10-500 µg L-1; limit of detection, 3.01 µg L-1; determination coefficient (R2), 0.9960; intra-day RSD, 5.28%; and inter-day RSD, 8.17%. The applicability of the method was assessed for the determination of vitamin D3 in different unfortified and fortified bovine milk samples, and the recoveries in the 71.8-113.3% range with the RSDs within 1.4-7.0% were obtained.


Assuntos
Biopolímeros/química , Carotenoides/química , Colecalciferol/análise , Grafite/química , Leite/química , Microextração em Fase Sólida/métodos , Animais , Bovinos , Colecalciferol/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Limite de Detecção , Modelos Lineares , Nanopartículas de Magnetita/química , Reprodutibilidade dos Testes
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