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1.
PeerJ ; 12: e17275, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38650646

RESUMO

Background: Sect. Chrysantha Chang, belonging to the Camellia genus, is one of the rare and precious ornamental plants distinguished by a distinctive array of yellow-toned petals. However, the variation mechanisms of petal color in Sect. Chrysantha Chang remains largely unclear. Methods: We conducted an integrated analysis of metabolome and transcriptome to reveal petal coloration mechanism in three species, which have different yellow tones petals, including C. chuongtsoensis (CZ, golden yellow), C. achrysantha (ZD, light yellow), and C. parvipetala (XB, milk white). Results: A total of 356 flavonoid metabolites were detected, and 295 differential metabolites were screened. The contents of 74 differential metabolites showed an upward trend and 19 metabolites showed a downward trend, among which 11 metabolites were annotated to the KEGG pathway database. We speculated that 10 metabolites were closely related to the deepening of the yellowness. Transcriptome analysis indicated that there were 2,948, 14,018 and 13,366 differentially expressed genes (DEGs) between CZ vs. ZD, CZ vs. XB and ZD vs. XB, respectively. Six key structural genes (CcCHI, CcFLS, CcDFR1, CcDFR2, CcDFR3, and CcCYP75B1) and five candidate transcription factors (MYB22, MYB28, MYB17, EREBP9, and EREBP13) were involved in the regulation of flavonoid metabolites. The findings indicate that flavonoid compounds influence the color intensity of yellow-toned petals in Sect. Chrysantha Chang. Our results provide a new perspective on the molecular mechanisms underlying flower color variation and present potential candidate genes for Camellia breeding.


Assuntos
Camellia , Flores , Regulação da Expressão Gênica de Plantas , Metaboloma , Pigmentação , Transcriptoma , Flores/genética , Flores/metabolismo , Metaboloma/genética , Pigmentação/genética , Camellia/genética , Camellia/metabolismo , Flavonoides/metabolismo , Perfilação da Expressão Gênica
2.
Org Lett ; 20(8): 2481-2484, 2018 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-29617139

RESUMO

A nickel complex/Lewis acid combination effectively catalyzed the direct silyl-Heck reaction of chlorosilanes, which are key raw materials in the organosilicon industry, to give synthetically important alkenylsilane products. Trichlorosilanes, dichlorosilanes, and monochlorosilanes underwent the silyl-Heck reaction to afford the corresponding alkenylsilanes in high yields. In the reactions of dichlorosilanes, a single substitution occurred to give monoalkenylsilanes in a highly selective manner.

3.
J Microbiol Biotechnol ; 25(5): 687-95, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25418480

RESUMO

Accumulating evidence indicates that lactic acid bacteria could improve host physiology and lipid metabolism. To investigate the effect of the gut microbiota on host lipid metabolism, a hyperlipidemic rat model was established by feeding rats a high-fat diet for 28 days, and the gut microbiota of the rats was analyzed using real-time PCR before and after administration of Lactobacillus rhamnosus hsryfm 1301 and its fermented milk for 28 days. The findings showed that the Lactobacillus spp., Bifidobacterium spp., Bacteroides spp., and Enterococcus spp. content in the hyperlipidemic rats gut was increased significantly (p < 0.05), while the Clostridium leptum and Enterobacter spp. content was decreased significantly after intervening with L. rhamnosus hrsyfm 1301 and its fermented milk for 28 days (p < 0.05). Furthermore, the lipid levels of the serum and the liver were decreased significantly (p < 0.05) and the fecal water content was increased significantly (p < 0.05) in the hyperlipidemic rats after the intervention, and hepatocyte fatty degeneration of liver tissues was also prevented. A positive correlation was observed between the Clostridium leptum content and the level of serum cholesterol, triglycerides, low-density lipoprotein, and high-density lipoprotein, and a negative correlation was observed between the Enterobacter spp. content and the Lactobacillus spp. and Bifidobacterium spp. content in the hyperlipidemic rats gut. These results suggest that the gut microbiota and lipid metabolism of hyperlipidemic rats could be improved by supplementation with L. rhamnosus hsryfm 1301 and its fermented milk.


Assuntos
Dieta Hiperlipídica , Microbioma Gastrointestinal/fisiologia , Lacticaseibacillus rhamnosus , Metabolismo dos Lipídeos/efeitos dos fármacos , Probióticos/farmacologia , Animais , Produtos Fermentados do Leite/metabolismo , Fezes/química , Fezes/microbiologia , Fígado/química , Fígado/efeitos dos fármacos , Masculino , Ratos , Ratos Wistar
4.
BMC Complement Altern Med ; 14: 386, 2014 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-25300818

RESUMO

BACKGROUND: Growing evidence indicates that intestinal microbiota regulate our metabolism. Probiotics confer health benefits that may depend on their ability to affect the gut microbiota. The objective of this study was to examine the effect of supplementation with the probiotic strain, Lactobacillus rhamnosus hsryfm 1301, on the gut microbiota in a hyperlipidemic rat model, and to explore the associations between the gut microbiota and the serum lipids. METHODS: The hyperlipidemic rat model was established by feeding rats a high-fat diet for 28 d. The rats' gut microbiota were analyzed using high-throughput sequencing before and after L. rhamnosus hsryfm 1301 supplementation or its fermented milk for 28 d. The serum lipids level was also tested. RESULTS: The rats' primary gut microbiota were composed of Bacteroidetes, Firmicutes, Proteobacteria, Spirochaetes and Verrucomicrobia. The abundance and diversity of the gut microbiota generally decreased after feeding with a high-fat diet, with a significant decrease in the relative abundance of Bacteroidetes, but with an increase in that of Firmicutes (P < 0.05). Administration of L. rhamnosus hsryfm 1301 or its fermented milk for 28 d, could recover the Bacteroidetes and Verrucomicrobia abundance and could decrease the Firmicutes abundance, which was associated with a significant reduction in the serum lipids' level in the hyperlipidemic rats with high-fat diet induced. The abundance of 22 genera of gut bacteria was changed significantly after probiotic intervention for 28 d (P < 0.05). A positive correlation was observed between Ruminococcus spp. and serum triglycerides, Dorea spp. and serum cholesterol (TC) and low-density lipoprotein (LDL-C), and Enterococcus spp. and high-density lipoprotein. The Butyrivibrio spp. negatively correlated with TC and LDL-C. CONCLUSIONS: Our results suggest that the lipid metabolism of hyperlipidemic rats was improved by regulating the gut microbiota with supplementation of L.rhamnosus hsryfm 1301 or its fermented milk for 28 d.


Assuntos
Trato Gastrointestinal/microbiologia , Hiperlipidemias/metabolismo , Lacticaseibacillus rhamnosus , Microbiota/efeitos dos fármacos , Probióticos/farmacologia , Animais , Dieta Hiperlipídica , Modelos Animais de Doenças , Fezes/microbiologia , Trato Gastrointestinal/efeitos dos fármacos , Hiperlipidemias/sangue , Lipídeos/sangue , Masculino , Análise de Componente Principal , Ratos , Ratos Sprague-Dawley
5.
Org Biomol Chem ; 8(10): 2320-2, 2010 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-20376384

RESUMO

A series of new chiral phosphine-phosphoramidite ligands with a 3,3'-substituted binaphthyl moiety were prepared from 1-phenylethylamine, and successfully applied in the Rh-catalyzed asymmetric hydrogenation of beta-(acylamino)-acrylates. The research disclosed that the substituents on the 3,3'-positions of binaphthyl moiety significantly influenced the enantioselectivity.


Assuntos
Acrilatos/química , Naftalenos/química , Compostos Organofosforados/química , Fenetilaminas/química , Fosfinas/química , Ródio/química , Catálise , Hidrogenação , Ligantes , Estereoisomerismo , Especificidade por Substrato
6.
Org Lett ; 11(15): 3226-9, 2009 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-19572604

RESUMO

A new class of chiral ferrocenyl diphosphine ligands with an imidazole ring, (R(c),S(Fc))-ImiFerroPhos, has been prepared from acylferrocenes through a five-step transformation and successfully applied in the Rh-catalyzed asymmetric hydrogenation of various 3-aryl-substituted 2-phosphonomethylpropenoates, in which a series of chiral 3-phosphono-2-arylmethylpropanoic acid derivatives were achieved in ee values of up to 98%.


Assuntos
Imidazóis/química , Organofosfonatos/síntese química , Ródio/química , Catálise , Cristalografia por Raios X , Hidrogenação , Ligantes , Organofosfonatos/química , Estereoisomerismo
7.
J Org Chem ; 73(15): 6022-4, 2008 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-18597530

RESUMO

A series of chiral beta-aryl-substituted gamma-amino butyric acid derivatives were synthesized in good enantioselectivities via the Cu-catalyzed asymmetric conjugate reduction of gamma-phthalimido-alpha,beta-unsaturated carboxylic acid esters using Cu(OAc)2 x H2O as a catalyst precursor, (S)-BINAP as a ligand, PMHS as a hydride source, and t-BuOH as an additive. The methodology has been applied successfully to the enantioselective synthesis of a chiral pharmaceutical, (R)-baclofen.


Assuntos
Aminoácidos/síntese química , Ácidos Carboxílicos/química , Cobre/química , Ésteres/química , Iminoácidos/química , Ftalimidas/química , Aminoácidos/química , Catálise , Ligantes , Estrutura Molecular , Oxirredução , Estereoisomerismo
8.
J Org Chem ; 73(5): 2011-4, 2008 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-18266386

RESUMO

A new class of unsymmetrical hybrid phosphine--aminophosphine ligands has been prepared from commercially available, inexpensive (S)-1-phenylethylamine through a concise synthetic procedure. These ligands are not very sensitive to air and moisture, and displayed good enantioselectivities in the Rh-catalyzed asymmetric hydrogenation of various dimethyl alpha-benzoyloxyethenephosphonates bearing beta-aryl, beta-alkyl, and beta-alkoxy substituents and N-benzyloxycarbonyl alpha-enamido phosphonates, in which up to 97% ee was obtained. A side-by-side comparison study disclosed that these new phosphine--aminophosphine ligands showed better enantioselectivity than BoPhoz ligands.

9.
J Org Chem ; 73(5): 2015-7, 2008 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-18229942

RESUMO

A series of BoPhoz-type ligands were successfully applied in the rhodium-catalyzed asymmetric hydrogenation of a number of beta-substituted or unsubstituted alpha-(phthalimidomethyl)acrylates, affording good to excellent enantioselectivities. The results suggested that the presence of an N-H proton in the BoPhoz backbone could significantly improve the enantioselectivity, and ligand (Sc,Rp)-1d, bearing two CF3-groups in the 3,5-position of the phenyl ring of aminophosphino moiety, showed the highest enantioselectivity.


Assuntos
Aminoácidos/síntese química , Organofosfonatos/química , Ródio/química , Aminoácidos/química , Ligantes , Espectroscopia de Ressonância Magnética , Espectrometria de Massas por Ionização por Electrospray , Estereoisomerismo
10.
Org Lett ; 9(23): 4825-8, 2007 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-17929937

RESUMO

A series of chiral beta-aryl-gamma-amino acid ester derivatives were synthesized in high enantioselectivities (93-97% ee) via the Rh-catalyzed asymmetric hydrogenation of gamma-phthalimido-alpha,beta-unsaturated carboxylic acid esters using highly modular chiral BoPhoz-type phosphine-aminophosphine ligands. The method has been applied successfully to the synthesis of several chiral pharmaceuticals including (R)-baclofen and (R)-rolipram with high enantioselectivities.


Assuntos
Aminoácidos/síntese química , Ésteres/química , Ródio/química , Aminoácidos/química , Baclofeno/síntese química , Baclofeno/química , Catálise , Hidrogenação , Ligantes , Estrutura Molecular , Rolipram/síntese química , Rolipram/química , Estereoisomerismo
12.
Org Lett ; 8(19): 4367-70, 2006 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-16956228

RESUMO

A new family of air- and moisture-stable phosphine-phosphoramidite ligands (PEAPhos) has been prepared from commercially available and inexpensive (S)-alpha-phenylethylamine through a two- or three-step transformation and successfully applied in the rhodium-catalyzed enantioselective hydrogenations of a variety of substrates, in which up to 99.9% ee was obtained for all of these kinds of substrates.

13.
Chem Commun (Camb) ; (3): 293-5, 2006 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-16391738

RESUMO

A new family of readily available, recoverable and soluble polymer-monophosphite ligands were prepared and successfully used in the Rh-catalyzed asymmetric hydrogenation of enamides and beta-dehydroamino acid esters, in which up to 99 and 99.9% ee were obtained, respectively.

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