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1.
Bioresour Technol ; 308: 123275, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32272391

RESUMO

A new bioprocess has been developed that allows for producing ß-carotene from the xylose portion of bioenergy sorghum. Bioenergy sorghum was pretreated in a pilot-scale continuous hydrothermal reactor followed by disc refining. Xylose was extracted using low-severity dilute acid hydrolysis. A xylose yield of 64.9% (17.4 g/L) was obtained by hydrolyzing at 120 °C for 5 min with 2% sulfuric acid. The xylose-enriched syrup was separated and concentrated to either 32 g xylose/L (medium-concentrated hydrolysate, MCB) or 66 g xylose/L (high-concentrated hydrolysate, HCB). The non- (NCB), medium-, and high-concentrated xylose syrup were neutralized and fermented to ß-carotene using Saccharomyces cerevisiae strain SR8B, which had been engineered for xylose utilization and ß-carotene production. In HCB, MCB, and NCB cultures, the yeast produced ß-carotene titers of 114.50 mg/L, 93.56 mg/L, and 82.50 mg/L, which corresponds to specific yeast biomass productions of 7.32 mg/g DCW, 8.10 mg/g DCW, and 8.29 mg/g DCW, respectively.


Assuntos
Sorghum , Xilose , Fermentação , Hidrólise , Saccharomyces cerevisiae , beta Caroteno
2.
Subcell Biochem ; 95: 27-55, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32297295

RESUMO

The placenta, a hallmark of mammalian embryogenesis, allows nutrients to be exchanged between the mother and the fetus. Vitamin A (VA), an essential nutrient, cannot be synthesized by the embryo, and must be acquired from the maternal circulation through the placenta. Our understanding of how this transfer is accomplished is still in its infancy. In this chapter, we recapitulate the early studies about the relationship between maternal dietary/supplemental VA intake and fetal VA levels. We then describe how the discovery of retinol-binding protein (RBP or RBP4), the development of labeling and detection techniques, and the advent of knockout mice shifted this field from a macroscopic to a molecular level. The most recent data indicate that VA and its derivatives (retinoids) and the pro-VA carotenoid, ß-carotene, are transferred across the placenta by distinct proteins, some of which overlap with proteins involved in lipoprotein uptake. The VA status and dietary intake of the mother influence the expression of these proteins, creating feedback signals that control the uptake of retinoids and that may also regulate the uptake of lipids, raising the intriguing possibility of crosstalk between micronutrient and macronutrient metabolism. Many questions remain about the temporal and spatial patterns by which these proteins are expressed and transferred throughout gestation. The answers to these questions are highly relevant to human health, considering that those with either limited or excessive intake of retinoids/carotenoids during pregnancy may be at risk of obtaining improper amounts of VA that ultimately impact the development and health of their offspring.


Assuntos
Desenvolvimento Embrionário , Vitamina A/metabolismo , Animais , Feminino , Humanos , Gravidez , Complicações na Gravidez/metabolismo , Proteínas de Ligação ao Retinol/metabolismo , Deficiência de Vitamina A/metabolismo , beta Caroteno/metabolismo
3.
Microbiol Res ; 236: 126455, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32179389

RESUMO

Echinenone and canthaxanthin are important carotenoid pigments with food and industrial applications. Biosynthesis of echinenone and/or canthaxanthin is catalyzed by ß-carotene ketolase (CrtO), with ß-carotene as the substrate. In this study, we generated transgenic Nostoc sp. PCC 7120 overexpressing a heterologous crtO gene from Nostoc flagelliforme and evaluated the productivity of both pigments. Normal (BG11 medium, 30 °C) and osmotic stress (BG11 medium supplemented with 0.4 M mannitol, 30 °C) conditions were used for cultivation. As compared to control strain, production of echinenone and canthaxanthin in transgenic strain were respectively increased by more than 16 % and 80 %, under either normal or osmotic stress conditions. Especially upon the stress condition, higher proportion of echinenone and canthaxanthin in total pigments was achieved, which should be beneficial for downstream separation and purification. In addition, transgenic strain showed drought tolerance and could revive from desiccation treatment after rewetting. Thus, this study provided technical clues for production of both pigments in engineered cyanobacteria as well as for cyanobacterial anhydrobiotic engineering.


Assuntos
Nostoc/genética , Organismos Geneticamente Modificados/crescimento & desenvolvimento , Organismos Geneticamente Modificados/metabolismo , Oxigenases/genética , Adaptação Fisiológica , Proteínas de Bactérias/genética , Cantaxantina/biossíntese , Carotenoides/metabolismo , Clonagem Molecular , Secas , Genes Bacterianos , Engenharia Metabólica/métodos , Nostoc/crescimento & desenvolvimento , Nostoc/metabolismo , Organismos Geneticamente Modificados/genética , Oxigenases/metabolismo , beta Caroteno/biossíntese
4.
Aquat Toxicol ; 222: 105472, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32203794

RESUMO

ß-carotene is an efficient antioxidant and its accumulation is an oxidative response to stressors. Dunaliella salina strain GY-H13 is rich in ß-carotene under environmental stresses, which was selected as material to understand the molecular mechanism underlying ß-carotene biosynthesis. Seven full length cDNA sequences in ß-carotene biosynthesis pathway were cloned, including geranylgeranyl pyrophosphate synthase (GGPS), phytoene synthase (PSY), phytoene desaturase (PDS), 15-cis-zeta-carotene isomerase (ZISO), zeta-carotene desaturase (ZDS), prolycopene isomerase (CRTISO), lycopene beta-cyclase (LCYb). The seven protein sequences from the strain GY-H13 showed the highest similarity with other D. salina strains. Especially, PSY, PDS and LCYb protein sequences shared 100 % identity. Phylogenetic analysis indicated all proteins from GY-H13 firstly clustered with those from other D. salina strains with a bootstrap of 100 %. Multiple alignment indicated several distinct conserved motifs such as aspartate-rich domain (ARD), dinucleotide binding domain (DBD), and carotene binding domain (CBD). These motifs are located near ligand-binding pocket, which may be required for the activity of enzyme. Expression levels of these genes and ß-carotene content were measured over 24-h cycle, showing clear daily dynamics. All genes were dramatically up-regulated in the morning but the highest accumulation of ß-carotene was observed at noon, suggesting a lag-effect between gene transcription and biological response. Furthermore, the accumulation of ß-carotene increased under nitrogen deficiency, Cd exposure and high light and decreased under high salinity in a time-dependent manner. No gene of ß-carotene biosynthesis was up-regulated by high salinity while most genes were activated by the other stresses at the beginning stage of exposure. Growth inhibition and oxidative damage were also observed under high salinity. Overall, transcription activation of ß-carotene biosynthetic genes at the initial stage of stress exposure is a determinant of the increased accumulation of ß-carotene in microalgae, which help their survive under harsh environments. The newly isolated D. salina strain GY-H13 would be a promising microalgae model for investigating the molecular mechanism of stress-induced ß-carotene biosynthesis.


Assuntos
Cádmio/toxicidade , Microalgas/efeitos dos fármacos , Ativação Transcricional/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , beta Caroteno/biossíntese , Sequência de Aminoácidos , Antioxidantes/metabolismo , Liases Intramoleculares/genética , Microalgas/genética , Microalgas/metabolismo , Oxirredutases/genética , Filogenia , Salinidade , beta Caroteno/genética
5.
J Agric Food Chem ; 68(9): 2747-2756, 2020 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-32028770

RESUMO

The induction period (IP) of ethyl linoleate stressed at 60 °C was monitored via the formation of hydroperoxides. The addition of lycopene (1% w/w) increased the IP from 7.0 to 10.0 h to prove the strong antioxidative potential in contrast to ß-carotene with pro-oxidative effects (IP: 6.0 h), both showing strong scavenging activity under fast degradation. When peroxidation was induced by singlet oxygen, both carotenoids effectively inhibited the formation of hydroperoxides, with quenching activity only observed at low singlet oxygen concentrations, while scavenging still dominated. Thus, carotenoids did not interact with the introduced singlet oxygen but rather with the radical intermediates of fat oxidation. These experiments were then transferred to lecithin-based micelles more related to biological systems, where singlet oxygen was generated in the outer aqueous phase. Lycopene and ß-carotene delayed or inhibited lipid peroxidation depending on concentration. In this setup, ß-carotene showed exclusively quenching activity, while lycopene was additionally degraded to about 70%.


Assuntos
Ácidos Linoleicos/química , Licopeno/química , beta Caroteno/química , Antioxidantes/química , Antioxidantes/farmacologia , Cinética , Lecitinas/química , Ácidos Linoleicos/farmacologia , Peroxidação de Lipídeos/efeitos dos fármacos , Modelos Químicos , Oxirredução , Oxigênio Singlete/química
6.
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
7.
Chemosphere ; 250: 126270, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32105851

RESUMO

It remains unknown if casts produced by earthworms exposed to a glyphosate-based herbicide (GBH) will retain their agricultural benefit. This study investigated the agricultural importance of surface casts produced by three earthworm species (Alma millsoni, Eudrilus eugeniae and Libyodrilus violaceus) exposed to a GBH on growth, fruit yield and quality of tomato (Lycopersicon esculentum). We sprayed 60 buckets (i.e 20 buckets/earthworm species) containing 20 adult earthworms of each species with 115.49 ml/m2 of Roundup® Alphée (Exposed) while another 60 buckets with earthworm species were sprayed with water (Control). Surface casts produced by the earthworms were collected for 1st, 2nd, 4th, 6th and 8th week post herbicide application. Tomato planting experiment on soil treated with the casts, NPK fertilizer and normal soil were grouped into 32 treatments. Tomato growth performance, yield and quality were evaluated with standard methods. Only the tomatoes planted with the casts of the exposed earthworms were unable to set fruit. There was no significant difference (p < 0.05) in yields of tomatoes planted with the control casts of E. eugeniae and A. millsoni compared to those planted with fertilizer. Vitamin C and ß-carotene contents increased in fruits of tomatoes planted with control cast of A. millsoni while reductions were recorded in the fruits of tomatoes planted with the control casts of E. eugeniae and L. violaceus relative to those planted with fertilizer. Surface casts of earthworms exposed to GBH could not enhance tomato growth while casts produced by unexposed earthworms greatly improved the performance of tomato plant.


Assuntos
Glicina/análogos & derivados , Herbicidas/toxicidade , Lycopersicon esculentum/crescimento & desenvolvimento , Oligoquetos/fisiologia , Agricultura , Animais , Fertilizantes/análise , Frutas/química , Glicina/toxicidade , Oligoquetos/química , Solo , beta Caroteno
8.
Ecotoxicol Environ Saf ; 192: 110313, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32066007

RESUMO

Cyanobacteria always massively grow and even occur blooms in summer, with releasing amount of ß-cyclocitral. To uncover the effects of summer high irradiance and temperature on cyanobacterial growth and ß-cyclocitral emission, the cell growth, reactive oxygen species (ROS) levels, photosynthetic pigment content, chlorophyll fluorescence and ß-cyclocitral emission were investigated in Microcystis aeruginosa under high light and temperature. Compared to the control under 50 µmol m-2·s-1, the cell growth was promoted under 100 µmol m-2·s-1, but inhibited under 500 and 1000 µmol m-2·s-1. The inhibition was also detected under high temperature at 30 and 35 °C in contrast to the control at 25 °C. Under high light and high temperature, M. aeruginosa increased ROS levels and reduced photosynthetic pigment content and photosystem II (PSII) efficiency, which resulted in the inhibition on cell growth. With increasing the light intensity and temperature, 1O2 levels gradually increased, while ß-carotene content gradually decreased by quenching 1O2, with increasing ß-cyclocitral emission. In summer, high irradiance and temperature not benefited the growth of cyanobacteria, but the emission of ß-cyclocitral derived from ß-carotene quenching 1O2 may offset the disadvantages by poisoning other algae.


Assuntos
Aldeídos/análise , Diterpenos/análise , Luz , Microcystis/química , Microcystis/crescimento & desenvolvimento , Temperatura , Microcystis/metabolismo , Microcystis/efeitos da radiação , Fotossíntese/efeitos da radiação , Complexo de Proteína do Fotossistema II/metabolismo , Espécies Reativas de Oxigênio/metabolismo , beta Caroteno/metabolismo
9.
Plant Foods Hum Nutr ; 75(2): 200-207, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32043228

RESUMO

The consumption of loquat fruits is highly appreciated for their carotenoid content and valuable sensory notes, but it is limited due to the low shelf-life. An on-line temperature controlled microwave system based on infrared thermography was used to dry three different loquat cultivar at 60 °C. The time to reach the target value of 23% moisture content was about 105 min in Claudia fruits and 162 min in Virticchiara and Peluche. Seven carotenoids were identified in loquat fruits, among these the major were all-trans-ß-carotene in Virticchiara and Claudia. Virticchiara had the major total carotenoid content (206 µg/g dry basis), followed by Peluche (158 µg/g d.b.) and Claudia (41 µg/g d.b.). The loss of carotenoids after drying ranged between 24% (Peluche) and 41% (Claudia). Carotenoids that showed a higher loss were on average: lutein (70%) and zeaxhantin (51%). Thirty-five volatile compounds were identified in fresh and dried loquats: the aldehydes were the most abundant class. After drying, aldehydes declined slightly, with alcohols falling more sharply. The shortened times by using temperature-controlled microwave heating with infrared thermography have guaranteed a fair quality of the dried loquats from the nutritional and sensory point of view, variable among the three cultivars.


Assuntos
Eriobotrya , Carotenoides , Frutas , Micro-Ondas , beta Caroteno
10.
Food Chem ; 316: 126354, 2020 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-32058195

RESUMO

The study reports shelf-life enhancement of candied mango by infusion of gingerols. Gingerols infused product (GIP), with 3.67 mg gingerols/100 g and non-infused products (control) were packed in multilayer metalized (MET), and ethylene vinyl alcohol (EVOH) based pouches and stored at 25, 35 and 45 °C for 120 days. Degradation kinetics of browning and related parameters showed following order: kß-carotene > ksensory (color) > knon-enzymatic browning > kvitamin C > kantioxidant capacity > k sensory (overall) > ktotal phenolics > kgingerols, resulting in multiple cutoff criteria and predicted shelf-lives (SLpredicted). The application of chemometrics simplified the kinetic interpretations and hence the predictions. Gingerols infusion retarded the deterioration of all quality parameters and substantially enhanced SLpredicted of GIP over control, irrespective of storage conditions. Finally, chemometric based SLpredicted of 144 days closely predicted the actual shelf-life of 142 days for control samples stored in EVOH pouches at 25 °C, in contrast to kinetics based SLpredicted of 185 days.


Assuntos
Catecóis/farmacologia , Álcoois Graxos/farmacologia , Mangifera/efeitos dos fármacos , Antioxidantes/metabolismo , Ácido Ascórbico/metabolismo , Doces , Cor , Armazenamento de Alimentos , Mangifera/metabolismo , Fenóis/metabolismo , beta Caroteno/metabolismo
11.
Food Chem ; 315: 126288, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32032833

RESUMO

ß-Carotene was encapsulated in the Pickering emulsions stabilized by chitosan hydrochloride - carboxymethyl starch (CHC-CMS) nanogels. During ultraviolet radiation and storage, the retention of ß-carotene in Pickering emulsions was higher than that of other formulations, such as Tween 80 stabilized emulsions (TEs) and bulk oil. The Pickering emulsions were found to be stable during thermal treatment. Meanwhile, lipid oxidation was delayed in Pickering emulsions compared to TEs and bulk oil. The vitro digestion results suggested that the free fatty acids (FFA) released were below 30% for all Pickering emulsions, which indicated that a physical barrier was formed by CHC-CMS nanogels to restrain the lipid hydrolysis. The bioaccessibility of ß-carotene in Pickering emulsions was higher than that in bulk oil. This research helped establish a connection between the physicochemical properties of CHC-CMS stabilized Pickering emulsions with their applications in the protection effect and oral delivery of bioactive compounds.


Assuntos
Quitosana/química , beta Caroteno/química , Quitosana/análogos & derivados , Emulsões/química , Ácido Clorídrico/química , Hidrólise , Lipídeos/química , Nanogéis/química , Oxirredução , Tamanho da Partícula , Amido/análogos & derivados , Raios Ultravioleta
14.
Food Chem ; 313: 126118, 2020 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-31945700

RESUMO

There is an ever-increasing need to protect health-beneficial ß-carotene (BC) from degradation with novel ingredients. Natural antioxidant-loaded protein-polysaccharide ternary complex has great potential for BC emulsions stabilization. In this study, curcumin (CUR)-loaded pea protein isolate (PPI), and high methoxyl pectin (HMP) ternary complex (804.0 nm) was fabricated by a self-assembly approach for BC emulsions stabilization. Highest CUR loading amount (LA, 33.19 µg/mg) was obtained in CUR-PPI-HMP complex. Hydrophobic interaction and hydrogen bonding were the prime driving forces for ternary complex formation. XRD results showed that CUR was amorphous. BC emulsion with PPI-HMP and CUR-PPI-HMP possessed higher droplet sizes (357.8 and 360.2 nm) than that with PPI and CUR-PPI (325.6, and 313.5 nm). Excellent physical stability with PPI-HMP and CUR-PPI-HMP was observed. BC retention with CUR-PPI-HMP was highest exposure to UV light (76.15%, 8 h), or heat treatment at 25 (91.50%) and 50 °C (74.35%) for 30 days.


Assuntos
Curcumina/química , Emulsões/química , Proteínas de Ervilha/química , Pectinas/química , beta Caroteno/química , Ligação de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Tamanho da Partícula , Temperatura , Raios Ultravioleta
15.
Food Chem ; 312: 126087, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-31911355

RESUMO

Beer has been one of the most consumed alcoholic beverages worldwide. However, the incorporation of adjuncts in the beer can add new organoleptic and functional characteristics to the beverage. For this, Beauregard sweet potato shows high potential due to being a rich source of starch and many bioactive compounds. The aim of this study was to develop the best process condition to produce a Sweet potato beer with enhanced nutritional and antioxidant properties and good sensory characteristics. Beer samples showed increased antioxidant activity especially due to ß-carotene and their total phenolic content. The phytochemical profile of sweet potato biocompounds demonstrated a direct effect of this adjunct on sensory and functional characteristics of the finished beer. In conclusion, it was found that Beauregard sweet potato is a promising adjunct for beer brewing with nutraceutical properties due to its rich composition of bioactive compounds.


Assuntos
Cerveja/análise , Ipomoea batatas/química , Antioxidantes/análise , Fenômenos Químicos , Fenóis/análise , Amido/química , beta Caroteno/análise
16.
Food Chem ; 314: 126157, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-31951891

RESUMO

In this work an electrohydrodynamic process (electrospray) was used to produce ß-carotene loaded nanocapsules based on whey protein isolate (WPI). WPI solutions were prepared in aqueous solutions with different concentrations of ethanol (5, 10 and 15%) which were used for ß-carotene solubilization. Different electrospray conditions were tested and the morphology and molecular organization of the nanocapsules were studied on dried and hydrated state. The size of the dried nanocapsules ranged between 227 and 283 nm. After hydration, there was a significant increase in the mean size of the nanocapsules, being the sizes higher for nanocapsules produced with increasing concentrations of ethanol. Results, obtained from the reactivity of free sulfhydryl groups and fluorescence analysis, showed that the increase of ethanol concentration had a destabilizing effect on the protein unfolding. Electrosprayed WPI-based nanocapsules can be used for the encapsulation of ß-carotene answering the industrial demand for novel encapsulation technologies to protect sensitive bioactive compounds.


Assuntos
Nanocápsulas/química , Proteínas do Soro do Leite/química , beta Caroteno/química , Animais , Bovinos , Elétrons , Microscopia Eletroquímica de Varredura , Nanocápsulas/ultraestrutura
17.
Food Chem ; 310: 125927, 2020 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-31835232

RESUMO

Two filamentous fungi (Actinomucor elegans and Umbelopsis isabellina), were tested for their ability to enrich white grape pomace simultaneously with both γ-linolenic acid (GLA) and carotenoids through solid-state fermentation (SSF) processes. U. isabellina presented higher ability to produce GLA-rich lipids (composed mainly of neutral fractions) than A. elegans (the 6-th day of SSF: 378.85 mg/100 g of pomace -U. isabellina and 193.36 mg/100 g of pomace- A. elegans). The amounts of ß-carotene and lutein for both SSFs gradually increased until the end of the fermentation processes. The effect of fermentation time on the phenolic content and antioxidant activity of grape pomace was also studied. The SSF with A. elegans increased significantly total phenolic and flavonoid contents and DPPH scavenging activity of grape popmace. These bioprocessed grape pomaces with significant amounts of carotenoids and GLA-rich lipids (>94% nutritionally-valuable polyunsaturated fatty acids at the sn-2 position) could be very attractive for food industry.


Assuntos
Antioxidantes/química , Carotenoides/química , Manipulação de Alimentos/métodos , Fungos não Classificados/metabolismo , Vitis/química , Ácido gama-Linolênico/química , Antioxidantes/metabolismo , Carotenoides/metabolismo , Fermentação , Flavonoides/metabolismo , Lipídeos/análise , Lipídeos/química , Fenóis/análise , Fenóis/metabolismo , beta Caroteno/metabolismo , Ácido gama-Linolênico/metabolismo
18.
Biochim Biophys Acta Mol Cell Res ; 1867(2): 118563, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31666191

RESUMO

Skeletal muscle secretes biologically active proteins that contribute to muscle hypertrophy in response to either exercise or dietary intake. The identification of skeletal muscle-secreted proteins that induces hypertrophy can provide critical information regarding skeletal muscle health. Dietary provitamin A, ß-carotene, induces hypertrophy of the soleus muscle in mice. Here, we hypothesized that skeletal muscle produces hypertrophy-inducible secretory proteins via dietary ß-carotene. Knockdown of retinoic acid receptor (RAR) γ inhibited the ß-carotene-induced increase soleus muscle mass in mice. Using RNA sequencing, bioinformatic analyses, and literature searching, we predicted transglutaminase 2 (TG2) to be an all-trans retinoic acid (ATRA)-induced secretory protein in cultured C2C12 myotubes. Tg2 mRNA expression increased in ATRA- or ß-carotene-stimulated myotubes and in the soleus muscle of ß-carotene-treated mice. Knockdown of RARγ inhibited ß-carotene-increased mRNA expression of Tg2 in the soleus muscle. ATRA increased endogenous TG2 levels in conditioned medium from myotubes. Extracellular TG2 promoted the phosphorylation of Akt, mechanistic target of rapamycin (mTOR), and ribosomal p70 S6 kinase (p70S6K), and inhibitors of mTOR, phosphatidylinositol 3-kinase, and Src (rapamycin, LY294002, and Src I1, respectively) inhibited TG2-increased phosphorylation of mTOR and p70S6K. Furthermore, extracellular TG2 promoted protein synthesis and hypertrophy in myotubes. TG2 mutant lacking transglutaminase activity exerted the same effects as wild-type TG2. Knockdown of G protein-coupled receptor 56 (GPR56) inhibited the effects of TG2 on mTOR signaling, protein synthesis, and hypertrophy. These results indicated that TG2 expression was upregulated through ATRA-mediated RARγ and that extracellular TG2 induced myotube hypertrophy by activating mTOR signaling-mediated protein synthesis through GPR56, independent of transglutaminase activity.


Assuntos
Proteínas de Ligação ao GTP/metabolismo , Receptores Acoplados a Proteínas-G/metabolismo , Transglutaminases/metabolismo , Animais , Crescimento Celular/efeitos dos fármacos , Linhagem Celular , Proteínas de Ligação ao GTP/genética , Fator de Crescimento Insulin-Like I/genética , Fator de Crescimento Insulin-Like I/metabolismo , Camundongos , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/metabolismo , Mioblastos/citologia , Mioblastos/metabolismo , Fosforilação/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Receptores Acoplados a Proteínas-G/antagonistas & inibidores , Receptores Acoplados a Proteínas-G/genética , Receptores do Ácido Retinoico/antagonistas & inibidores , Receptores do Ácido Retinoico/genética , Receptores do Ácido Retinoico/metabolismo , Receptor alfa de Ácido Retinoico/antagonistas & inibidores , Receptor alfa de Ácido Retinoico/genética , Receptor alfa de Ácido Retinoico/metabolismo , Proteínas Quinases S6 Ribossômicas 70-kDa/metabolismo , Transdução de Sinais/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismo , Transglutaminases/genética , Tretinoína/farmacologia , beta Caroteno/administração & dosagem , beta Caroteno/farmacologia
19.
Nat Prod Res ; 34(1): 93-101, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31172806

RESUMO

Chemical characteristics of novel seed oils, yet not investigated, from three endemic Arecaceae (palm) species from Reunion Island are described. Fatty acid profiles are performed using two-dimensional gas chromatography-mass spectrometry. Carotenoid contents are determined by high performance liquid chromatography-mass spectrometry. The results of the investigations emphasize the particular composition of the unconventional red seed oil from Hyophorbe indica. Characteristic features of this oil reveal a high degree of unsaturation (50% of polyunsaturated fatty acids, with a high content (17%) of omega-3), which is possibly a unique fatty acid composition in the Arecaceae family. The two other palm oils from Dictyosperma album and Latania lontaroides contain high level of saturated fatty acids very similar to that of the edible palm oil. H. indica oil is also very rich in valuable carotenoids; in particular, lutein, ß-carotene and lycopene are detected in a high content (respectively 45, 23 and 35 mg.kg-1 in oil).


Assuntos
Arecaceae/química , Óleo de Palmeira/química , Óleos Vegetais/química , Carotenoides/análise , Ácidos Graxos/análise , Ácidos Graxos Insaturados/análise , Cromatografia Gasosa-Espectrometria de Massas , Luteína/análise , Reunião , Sementes/química , beta Caroteno/análise
20.
Plant Foods Hum Nutr ; 75(1): 63-69, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31838615

RESUMO

In this work, lycopene- and ß-carotene-rich extracts were obtained from guava's pulp and waste powders using maceration (ME), ultrasonic bath (BUAE, 25 °C for 30 min), and ultrasonic probe (PUAE, 25 °C for 5 min). Extracts were evaluated for total carotenoid content, antioxidant capacity, color, and lycopene and ß-carotene content by HPLC-DAD. Bath-type ultrasound-assisted extraction (BUAE) was the best technique to obtain lycopene from guava pulp (135.0 mg 100 g-1) and waste (76.64 mg 100 g-1), followed by ME (pulp = 107.6, waste = 43.57 mg 100 g-1), and PUAE (pulp = 44.19, waste = 33.83 mg 100 g-1). The total carotenoid content positively affected the extracts' antioxidant capacity. Dehydration of guava fractions showed to be an efficient method to increase carotenoid availability. This is the first work to report the recovery of carotenoids from guava by ultrasonic extraction. Furthermore, this method has shown to be a suitable approach to reduce extraction time and solvent use. These extracts could be further applied to lipid-rich foods as a natural antioxidant and/or as an ingredient in the development of functional foods.


Assuntos
Psidium , Antioxidantes , Carotenoides , Pós , beta Caroteno
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