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1.
Nutrients ; 13(4)2021 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-33924335

RESUMO

Obesity and its related complications are a world-wide health problem. Dietary tocotrienols (TT) have been shown to improve obesity-associated metabolic disorders, such as hypercholesterolemia, hyperglycemia, and gut dysbiosis. This study examined the hypothesis that the antioxidant capacity of TT alters metabolites of oxidative stress and improves systemic metabolism. C57BL/6J mice were fed either a high-fat diet (HFD control) or HFD supplemented with 800 mg annatto-extracted TT/kg (HFD+TT800) for 14 weeks. Sera from obese mice were examined by non-targeted metabolite analysis using UHPLC/MS. Compared to the HFD group, the HFD+TT800 group had higher levels of serum metabolites, essential amino acids (lysine and methionine), sphingomyelins, phosphatidylcholine, lysophospholipids, and vitamins (pantothenate, pyridoxamine, pyridoxal, and retinol). TT-treated mice had lowered levels of serum metabolites, dicarboxylic fatty acids, and inflammatory/oxidative stress markers (trimethylamine N-oxide, kynurenate, 12,13-DiHOME, and 13-HODE + 9-HODE) compared to the control. The results suggest that TT supplementation lowered inflammation and oxidative stress (oxidized glutathione and GSH/GSSH) and improved macronutrient metabolism (carbohydrates) in obese mice. Thus, TT actions on metabolites were beneficial in reducing obesity-associated hypercholesterolemia/hyperglycemia. The effects of a non-toxic dose of TT in mice support the potential for clinical applications in obesity and metabolic disease.


Assuntos
Antioxidantes/administração & dosagem , Bixaceae/química , Carotenoides/química , Suplementos Nutricionais , Obesidade/dietoterapia , Extratos Vegetais/química , Tocotrienóis/administração & dosagem , Animais , Antioxidantes/isolamento & purificação , Dieta Hiperlipídica/efeitos adversos , Modelos Animais de Doenças , Humanos , Inflamação/sangue , Inflamação/diagnóstico , Inflamação/dietoterapia , Inflamação/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Nutrientes/metabolismo , Obesidade/sangue , Obesidade/etiologia , Obesidade/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Tocotrienóis/isolamento & purificação
2.
Molecules ; 26(9)2021 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-33925848

RESUMO

Leafy green vegetables contain essential nutrients and are frequently consumed for their perceived health benefits. The purpose of this study was to profile the nutritional and natural bioactive phytochemical compounds extracted from freeze-dried spinach and kale and compare them with our previously published freeze-dried purslane results. Novel research suggests that these leafy greens contain an abundance of fatty acids, amino acids, organic acids, vitamins, and minerals, which can reduce the risk of many chronic diseases. LC-MS/MS screening identified 69 and 103 compounds in spinach and kale, respectively, including flavonoids, glucosinolates, and phenolic and organic acids. Out of a total of 26 flavonoids identified in the current study, only three were found in spinach. All three leafy greens showed nutritional and health benefits and the unique phytochemical compounds found only in purslane provide a strong basis to incorporate its distinct dietary benefits.


Assuntos
Produtos Biológicos/química , Produtos Biológicos/farmacologia , Brassica/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Portulaca/química , Spinacia oleracea/química , Aminoácidos/química , Carotenoides/química , Cromatografia Líquida , Ácidos Graxos , Humanos , Minerais/química , Compostos Fitoquímicos/química , Compostos Fitoquímicos/farmacologia , Espectrometria de Massas em Tandem , Verduras/química
3.
Molecules ; 26(6)2021 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-33807056

RESUMO

Kashmir saffron (Crocus sativus L.), also known as Indian saffron, is an important Asian medicinal plant with protective therapeutic applications in brain health. The main bioactive in Kashmir or Indian Saffron (KCS) and its extract (CSE) are apocarotenoids picrocrocin (PIC) and safranal (SAF) with carotenoids, crocetin esters (crocins), and crocetins. The ultra-fast liquid chromatography(UFLC)- photodiode array standardization confirmed the presence of biomarkers PIC, trans-4-GG-crocin (T4C), trans-3-Gg-crocin (T3C), cis-4-GG-crocin (C4C), trans-2-gg-crocin (T2C), trans-crocetin (TCT), and SAF in CSE. This study's objectives were to develop and validate a sensitive and rapid UFLC-tandem mass spectrometry method for PIC and SAF along T4C and TCT in rat plasma with internal standards (IS). The calibration curves were linear (R2 > 0.990), with the lower limit of quantification (LLOQ) as 10 ng/mL. The UFLC-MS/MS assay-based precision (RSD, <15%) and accuracy (RE, -11.03-9.96) on analytical quality control (QC) levels were well within the acceptance criteria with excellent recoveries (91.18-106.86%) in plasma samples. The method was applied to investigate the in vivo pharmacokinetic parameters after oral administration of 40 mg/kg CSE in the rats (n = 6). The active metabolite TCT and T4C, PIC, SAF were quantified for the first time with T3C, C4C, T2C by this validated bioanalytical method, which will be useful for preclinical/clinical trials of CSE as a potential neuroprotective dietary supplement.


Assuntos
Carotenoides , Crocus/química , Fármacos Neuroprotetores , Extratos Vegetais , Animais , Carotenoides/química , Carotenoides/farmacocinética , Carotenoides/farmacologia , Cromatografia Líquida de Alta Pressão , Masculino , Espectrometria de Massas , Fármacos Neuroprotetores/química , Fármacos Neuroprotetores/farmacocinética , Fármacos Neuroprotetores/farmacologia , Extratos Vegetais/química , Extratos Vegetais/farmacocinética , Extratos Vegetais/farmacologia , Ratos , Ratos Sprague-Dawley
4.
Molecules ; 26(5)2021 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-33669124

RESUMO

Schizophrenia is a chronic mental devastating disease. Current therapy suffers from various limitations including low efficacy and serious side effects. Thus, there is an urgent necessity to develop new antipsychotics with higher efficacy and safety. The dried stigma of the plant Crocus sativus L., (CS) commonly known as saffron, are used in traditional medicine for various purposes. It has been demonstrated that saffron and its bioactive components crocins and safranal exert a beneficial action in different pathologies of the central nervous system such as anxiety, depression, epilepsy and memory problems. Recently, their role as potential antipsychotic agents is under investigation. In the present review, I intended to critically assess advances in research of these molecules for the treatment of schizophrenia, comment on their advantages over currently used neuroleptics as well-remaining challenges. Up to our days, few preclinical studies have been conducted to this end. In spite of it, results are encouraging and strongly corroborate that additional research is mandatory aiming to definitively establish a role for saffron and its bioactive components for the treatment of schizophrenia.


Assuntos
Antipsicóticos/uso terapêutico , Carotenoides/uso terapêutico , Crocus/química , Cicloexenos/uso terapêutico , Extratos Vegetais/uso terapêutico , Esquizofrenia/tratamento farmacológico , Terpenos/uso terapêutico , Animais , Antipsicóticos/química , Antipsicóticos/isolamento & purificação , Carotenoides/química , Carotenoides/isolamento & purificação , Cicloexenos/química , Cicloexenos/isolamento & purificação , Humanos , Medicina Tradicional , Estrutura Molecular , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Terpenos/química , Terpenos/isolamento & purificação
5.
Food Chem ; 353: 129455, 2021 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-33711704

RESUMO

The removal of plant pigments such as ß-carotene is an aspect of vegetable oil processing often desired by the food and pharmaceutical industries. Adsorption of ß-carotene to acid-activated clay (AAC) is a well-established method for purification. Despite this, the removal mechanism of ß-carotene is not well understood. UPLC-MS/MS analysis of surface compounds extracted from ß-carotene-AAC (BC-AAC) complexes show that AAC acts as an oxidiser. Oxidation products detected included canthaxanthin and 3',4'-didehydro-ß-caroten-4-one. AAC had surface water exchanged with an 18O labelled water and was then exposed to ß-carotene. Carotenoids labelled with 18O were produced from this reaction, suggesting surface water is necessary for ß-carotene removal.


Assuntos
Indústria de Processamento de Alimentos/métodos , Óleos Vegetais/química , beta Caroteno/análise , beta Caroteno/isolamento & purificação , 2-Propanol/química , Cantaxantina/análise , Cantaxantina/química , Carotenoides/análise , Carotenoides/química , Cromatografia Líquida/métodos , Argila/química , Oxirredução , Isótopos de Oxigênio/química , Extratos Vegetais/análise , Extratos Vegetais/química , Solventes , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrometria de Massas em Tandem/métodos , Água/química , beta Caroteno/química
6.
Food Chem ; 349: 129140, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-33582545

RESUMO

In this work, cellulose acetate films were prepared with the incorporation of different carotenoids (lycopene, norbixin, and zeaxanthin). The effect of adding these natural antioxidants was evaluated through stability during storage under controlled conditions (temperature and light), degradation rate coefficient, release in food simulants and protective effect on oxidation of vitamin B2. During storage at 25 °C or 40 °C the light showed a greater effect on the stability of the carotenoids, with significant increase in reaction constants (k) and decrease in half-life (t1/2). The degradation of the carotenoids was followed by a variation in the color parameters and mechanical properties. The films with norbixin showed the highest barrier to the transmission of UV-Vis light, consequently preserving 72% of a vitamin B2 stored under a photooxidative environment. Lycopene presented a higher release rate than norbixin and zeaxanthin to a fatty food simulant.


Assuntos
Carotenoides/química , Celulose/análogos & derivados , Embalagem de Alimentos/métodos , Armazenamento de Alimentos/métodos , Celulose/química , Cor , Oxirredução
7.
Molecules ; 26(4)2021 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-33561944

RESUMO

Dry eye disease (DED) is a multifactorial condition caused by tear deficiency and accompanied by ocular surface damage. Recent data support a key role of oxidative and inflammatory processes in the pathogenesis of DED. Hyaluronic acid (HA) is widely used in artificial tears to treat DED by improving ocular hydration and reducing surface friction. Crocin (Cr), the main constituent of saffron, is a renowned compound that exhibits potent antioxidant and anti-inflammatory effects. The present study was undertaken to assess the viscosity and muco-adhesiveness of a photoactivated formulation with crosslinked HA (cHA), Cr, and liposomes (cHA-Cr-L). Our aim was also to evaluate whether cHA-Cr-L may exert cytoprotective effects against oxidative and inflammatory processes in human corneal epithelial cells (HCECs). Viscosity was measured using a rotational rheometer, and then the muco-adhesiveness was evaluated. Under hyperosmolarity (450 mOsm), the HCECs were treated with cHA-Cr-L. Interleukin-1ß (IL-1ß) and tumor necrosis factor α (TNFα) were quantified by quantitative real-time polymerase chain reaction (RT-qPCR). The levels of reactive oxygen species (ROS) were measured using the DCF assay. The combined action of cHA-Cr-L produced a higher viscosity and muco-adhesiveness compared to the control. The anti-inflammatory effect of cHA-Cr-L was achieved through a significant reduction of IL-1ß and TNFα (p < 0.001). The results also showed that cHA-Cr-L reduces ROS production under conditions of hyperosmolarity (p < 0.001). We conclude that cHA-Cr-L has potential as a therapeutic agent in DED, which should be further investigated.


Assuntos
Carotenoides/química , Citoproteção/efeitos dos fármacos , Síndromes do Olho Seco/tratamento farmacológico , Ácido Hialurônico/química , Ácido Hialurônico/farmacologia , Lipossomos/química , Animais , Córnea/patologia , Síndromes do Olho Seco/patologia , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/patologia , Humanos , Ácido Hialurônico/uso terapêutico , Viscosidade
8.
Oxid Med Cell Longev ; 2021: 6610124, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33603948

RESUMO

Nonalcoholic fatty liver disease is the most common liver disease worldwide. Hepatic steatosis and oxidative stress are the main characteristics of NAFLD (nonalcoholic fatty liver disease), which also affect its prognosis. Bixin acts as novel Nrf2 (NF-E2 p45-related factor 2) activator with the cytoprotection against oxidative stress and inflammation; this study mainly focused on the mechanism of Nrf2 activation by bixin and explored its potential feasibilities in long-term high-fat diet- (HFD-) caused hepatic steatosis and inflammatory response in vitro and in vivo. Bixin was found to activate Nrf2 signals by the modification of critical Keap1 (Kelch-like ECH-associated protein 1) cystine and competitive interaction with Keap1 with upregulating P62 mRNA and protein expression. In human liver cells exposed to FFA (free fatty acid), bixin displayed a pronounced cytoprotective activity with upregulation of Nrf2-mediated gene expression, such as PPARα and its targets related with fatty acid oxidation. In HFD-fed mice, systemic administration of bixin attenuated lipid accumulation, decreased oxidant inflammatory damage in the liver, and reduced circulating lipid levels through Nrf2. Different from most of other established inducers, bixin activated Nrf2 signals through two different mechanisms with safe administration for protection of oxidant inflammatory damage and attenuation of lipid accumulation in the in vivo long-term HFD-fed mice. Bixin represents a prototype Nrf2 activator that displays cytoprotective activity upon system administration targeting hepatic steatosis and oxidant inflammation originating from long-term HFD-fed mice. And bixin-based Nrf2-directed systemic intervention may also provide therapeutic benefit in protecting other organs in the process of metabolic syndrome.


Assuntos
Carotenoides/uso terapêutico , Fígado Gorduroso/tratamento farmacológico , Fígado Gorduroso/metabolismo , Inflamação/patologia , Fator 2 Relacionado a NF-E2/metabolismo , PPAR alfa/metabolismo , Transdução de Sinais , Animais , Carotenoides/química , Carotenoides/farmacologia , Linhagem Celular , Cisteína/metabolismo , Citoproteção/efeitos dos fármacos , Dieta Hiperlipídica , Fígado Gorduroso/patologia , Comportamento Alimentar , Humanos , Inflamação/complicações , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Fígado/patologia , Camundongos Knockout , Estabilidade Proteica/efeitos dos fármacos , Ubiquitinação/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos
9.
Molecules ; 26(3)2021 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-33498727

RESUMO

Olive pomace is a semisolid by-product of olive oil production and represents a valuable source of functional phytocompounds. The valorization of agro-food chain by-products represents a key factor in reducing production costs, providing benefits related to their reuse. On this ground, we herein investigate extraction methods with supercritical carbon dioxide (SC-CO2) of functional phytocompounds from olive pomace samples subjected to two different drying methods, i.e., freeze drying and hot-air drying. Olive pomace was produced using the two most common industrial olive oil production processes, one based on the two-phase (2P) decanter and one based on the three-phase (3P) decanter. Our results show that freeze drying more efficiently preserves phytocompounds such as α-tocopherol, carotenoids, chlorophylls, and polyphenols, whereas hot-air drying does not compromise the ß-sitosterol content and the extraction of squalene is not dependent on the drying method used. Moreover, higher amounts of α-tocopherol and polyphenols were extracted from 2P olive pomace, while ß-sitosterol, chlorophylls, and carotenoids were more concentrated in 3P olive pomace. Finally, tocopherol and pigment/polyphenol fractions exerted antioxidant activity in vitro and in accelerated oxidative conditions. These results highlight the potential of olive pomace to be upcycled by extracting from it, with green methods, functional phytocompounds for reuse in food and pharmaceutical industries.


Assuntos
Dióxido de Carbono/química , Composição de Medicamentos/métodos , Olea/química , Antioxidantes/química , Carotenoides/química , Clorofila/química , Azeite de Oliva/química , Extratos Vegetais/química , Polifenóis/química , Sitosteroides/química , Tocoferóis/química
10.
Food Chem ; 340: 127901, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-32889204

RESUMO

Cauliflowers are generally associated with healthy diets due to their positive impact on health. This research aims to evaluate the effects of cooking processes (boiling, steaming and microwaving) and different preparation times, on the content of carotenoids and provitamin A and tocopherols, in cauliflowers and to verify the effect of the cooking process on maintaining the coloring. The results revealed that the thermal processinfluencedthe antioxidant compounds releaseindependent of genotype. The highest content of zeaxanthin and lutein was found in 'Verde di Macerata' after boiling for 20 min. 'Cheddar' presented the highest content of all carotenoids and when steamed for 20 min, the highest levels ofprovitamin Awere observed.Microwaved and bolied 'Grafitti' for longer times showed the highest retention of tocopherol. The cooking did not negatively affect the visual aspect. 'Verde di Macerata' and 'Cheddar' may be good sources of carotenoids and tocopherols.


Assuntos
Brassica/química , Carotenoides/análise , Culinária/métodos , Tocoferóis/análise , Antioxidantes/análise , Antioxidantes/química , Brassica/genética , Carotenoides/química , Genótipo , Pigmentação , Fatores de Tempo , Tocoferóis/química , Vitamina E/análise , Vitamina E/química
11.
Food Chem ; 338: 128004, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-32950868

RESUMO

The aim was to enhance provitamin A carotenoid (proVA CAR) concentrations and bioaccessibility in carrots by manipulating post-harvest factors. To that end, we assessed the effects of Ultraviolet-C light, pulsed light, storage temperature, and storage duration. We also measured CAR bioaccessibility by using an in vitro model. Pulsed light, but not Ultraviolet-C, treatment increased proVA CAR concentrations in the cortex tissue (p < 0.05). Longer storage times and higher temperatures also increased concentrations (p < 0.05). The maximal increase induced by pulsed light was obtained after treatment with 20 kJ/m2 and 3-days of storage at 20 °C. However, the positive effect induced by pulsed light decreased considerably over the next seven days. ProVA CAR in carrots with the highest concentrations also proved to be more bioaccessible (p < 0.05). Thus, proVA CAR concentrations in stored carrots can be increased significantly through storage times and temperatures. Pulsed light can also significantly increase proVA CAR concentrations, but only temporarily.


Assuntos
Carotenoides/análise , Daucus carota/química , Armazenamento de Alimentos/métodos , Provitaminas/análise , Disponibilidade Biológica , Carotenoides/química , Digestão , Luz , Provitaminas/química , Provitaminas/farmacocinética , Temperatura , Fatores de Tempo , Raios Ultravioleta , Vitamina A/química
12.
Food Chem ; 335: 127649, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-32738538

RESUMO

Rosa rugosa Thunb. seed oil (RR) extracted by supercritical CO2 was investigated. RR chemical composition, radical scavenging effect and oxidative stability were evaluated. RR aqueous emulsions were examined for cell cytotoxicity, proliferation, redox state and migration using mouse embryonic fibroblast Balb/3T3, human dermal fibroblast NHDF cell lines, and on neoplastic cell lines: acute monocytic leukemia THP-1 and lung adenocarcinoma A549. RR total contents of phytosterols, tocopherols, carotenoids and phenolics were 10115.23, 784.16, 40.32 and 10.30 mg/kg, respectively. Rich antioxidant composition of RR was reflected in its high antioxidant activity (2.1 mM/kg Trolox equivalent) as well as oxidative stability (activation energy 105.6 kJ/mol). The RR emulsions led to marked augmentation of the total cell protein content in BALB/3T3 and NHDF cultures, inhibited cancer cell migration and reduced ROS formation. The studied RR oil proved to have a remarkable combination of bioactive compounds and to exert an antioxidative and chemopreventive effects.


Assuntos
Óleos Vegetais/química , Óleos Vegetais/farmacologia , Rosa/química , Animais , Antioxidantes/química , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Dióxido de Carbono/química , Carotenoides/química , Carotenoides/isolamento & purificação , Carotenoides/farmacologia , Linhagem Celular , Cromatografia com Fluido Supercrítico , Humanos , Camundongos , Oxirredução , Fenóis/química , Fenóis/isolamento & purificação , Fenóis/farmacologia , Fitosteróis/química , Fitosteróis/isolamento & purificação , Fitosteróis/farmacologia , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Óleos Vegetais/isolamento & purificação , Sementes/química , Tocoferóis/química , Tocoferóis/isolamento & purificação , Tocoferóis/farmacologia
13.
Molecules ; 25(24)2020 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-33321863

RESUMO

Conversion of sunlight into photochemistry depends on photoprotective processes that allow safe use of sunlight over a broad range of environmental conditions. This review focuses on the ubiquity of photoprotection associated with a group of interconvertible leaf carotenoids, the xanthophyll cycle. We survey the striking plasticity of this process observed in nature with respect to (1) xanthophyll cycle pool size, (2) degree and speed of interconversion of its components, and (3) flexibility in the association between xanthophyll cycle conversion state and photoprotective dissipation of excess excitation energy. It is concluded that the components of this system can be independently tuned with a high degree of flexibility to produce a fit for different environments with various combinations of light, temperature, and other factors. In addition, the role of genetic variation is apparent from variation in the response of different species growing side-by-side in the same environment. These findings illustrate how field studies can generate insight into the adjustable levers that allow xanthophyll cycle-associated photoprotection to support plant photosynthetic productivity and survival in environments with unique combinations of environmental factors.


Assuntos
Meio Ambiente , Substâncias Protetoras/química , Substâncias Protetoras/farmacologia , Zeaxantinas/química , Zeaxantinas/farmacologia , Vias Biossintéticas , Carotenoides/química , Carotenoides/metabolismo , Carotenoides/farmacologia , Fenômenos Fisiológicos da Nutrição , Fotossíntese/efeitos dos fármacos , Compostos Fitoquímicos/química , Compostos Fitoquímicos/farmacologia , Folhas de Planta/metabolismo , Fenômenos Fisiológicos Vegetais , Luz Solar , Tempo (Meteorologia) , Zeaxantinas/biossíntese
14.
Proc Natl Acad Sci U S A ; 117(33): 19914-19925, 2020 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-32747548

RESUMO

Apocarotenoids are important signaling molecules generated from carotenoids through the action of carotenoid cleavage dioxygenases (CCDs). These enzymes have a remarkable ability to cleave carotenoids at specific alkene bonds while leaving chemically similar sites within the polyene intact. Although several bacterial and eukaryotic CCDs have been characterized, the long-standing goal of experimentally visualizing a CCD-carotenoid complex at high resolution to explain this exquisite regioselectivity remains unfulfilled. CCD genes are also present in some archaeal genomes, but the encoded enzymes remain uninvestigated. Here, we address this knowledge gap through analysis of a metazoan-like archaeal CCD from Candidatus Nitrosotalea devanaterra (NdCCD). NdCCD was active toward ß-apocarotenoids but did not cleave bicyclic carotenoids. It exhibited an unusual regiospecificity, cleaving apocarotenoids solely at the C14'-C13' alkene bond to produce ß-apo-14'-carotenals. The structure of NdCCD revealed a tapered active site cavity markedly different from the broad active site observed for the retinal-forming Synechocystis apocarotenoid oxygenase (SynACO) but similar to the vertebrate retinoid isomerase RPE65. The structure of NdCCD in complex with its apocarotenoid product demonstrated that the site of cleavage is defined by interactions along the substrate binding cleft as well as selective stabilization of reaction intermediates at the scissile alkene. These data on the molecular basis of CCD catalysis shed light on the origins of the varied catalytic activities found in metazoan CCDs, opening the possibility of modifying their activity through rational chemical or genetic approaches.


Assuntos
Archaea/enzimologia , Proteínas Arqueais/química , Carotenoides/metabolismo , Dioxigenases/química , Archaea/química , Archaea/classificação , Archaea/genética , Proteínas Arqueais/genética , Proteínas Arqueais/metabolismo , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Carotenoides/química , Catálise , Domínio Catalítico , Dioxigenases/genética , Dioxigenases/metabolismo , Especificidade por Substrato , Synechocystis/química , Synechocystis/enzimologia , Synechocystis/genética
15.
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
16.
Food Chem ; 333: 127502, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-32683257

RESUMO

The aim of this study was to evaluate the effectiveness of the use of ethanol, ultrasound and/or vacuum as a pretreatment to melon drying. Eight types of pretreatments were performed in which samples were immersed in ethanol solutions with different concentrations (50% and 100%) using four treatment conditions: immersion, immersion with ultrasound (US), with vacuum (VC) and with ultrasound and vacuum (USVC). Drying was performed at 60 °C and five different semi-theoretical drying mathematical models were examined to characterize the drying curves, and quality analyses were carried out. The condition that obtained the lower drying time was using the US pretreatment in 100% ethanol solution. Drying caused a diminution of bioactive compounds and influenced color parameters. However, the samples immersed in 50% ethanol solution and dried obtained minor losses of total phenolics, total carotenoids, and ascorbic acid contents.


Assuntos
Cucurbitaceae/química , Etanol/farmacologia , Conservação de Alimentos/métodos , Conservantes de Alimentos/farmacologia , Ácido Ascórbico/análise , Carotenoides/química , Cor , Cucurbitaceae/efeitos dos fármacos , Dessecação , Conservação de Alimentos/instrumentação , Frutas/química , Frutas/efeitos dos fármacos , Fenóis/química , Vácuo
17.
Food Chem ; 330: 127223, 2020 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-32521401

RESUMO

The carotenoids in the peel and flesh of 41 apricot cultivars were qualitatively and quantitatively analysed by UHPLC-APCI-MS/MS, and the L*, a*, b* and quality indexes of the fruits were determined. The results showed that the L*, a*, b* and quality indexes of the fruits were quite different, and 13 carotenoids were detected in the peel and flesh of apricots, among which ε-carotene, α-cryptoxanthin and apocarotenal were newly detected carotenoids in apricots. The total carotenoid content of the 41 apricot cultivars varied from 20.983 to 320.278 µg/g FW, and the total carotenoid content varied from 17.353 to 222.098 µg/g FW in the peel and from 2.536 to 98.179 µg/g FW in the flesh. The main components of apricot fruits were ß-carotene and (E/Z)-phytoene, followed by ß-cryptoxanthin and lutein. This study shows that carotenoids in apricot fruits have rich metabolic diversity.


Assuntos
Carotenoides/análise , Prunus armeniaca/química , Carotenoides/química , China , Cromatografia Líquida de Alta Pressão , Frutas/química , Espectrometria de Massas em Tandem
18.
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
19.
Food Chem ; 331: 127259, 2020 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-32562977

RESUMO

Production of high-quality healthy foods through sustainable methodologies is an urgent necessity. High pressure homogenization (HPH) is an interesting alternative to obtain premium citrus juices, but its effects on bioactive compounds are unclear. There was studied the influence of HPH (150 MPa) and pasteurization (92 °C for 30 s and 85 °C for 15 s) processing on physicochemical properties and in vitro bioaccessibility of carotenoids and flavonoids in orange juices. Regarding fresh juice, physicochemical properties of samples remained unchanged although cloudiness was improved by homogenization. Pasteurization did not affect total carotenoids content and retinol activity equivalents (RAE) of juices whereas homogenization yielded a significant reduction (1.37 and 1.35-fold, respectively). Interestingly, particle size reduction from homogenization drastically enhanced (about 5-fold) bioaccessibility of carotenoids including hardly bioaccessible epoxycarotenoids, finding unaltered rates in pasteurized samples. Bioaccessibility of flavonoids was constant in all cases. Results can promote HPH as an efficient option to obtain health-enhanced foods.


Assuntos
Carotenoides/química , Citrus sinensis/química , Flavonoides/química , Manipulação de Alimentos/métodos , Sucos de Frutas e Vegetais/análise , Carotenoides/análise , Cromatografia Líquida de Alta Pressão , Citrus sinensis/metabolismo , Flavonoides/análise , Tamanho da Partícula , Pasteurização , Pressão
20.
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
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