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1.
Clin Nutr Res ; 10(3): 268-277, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34386445

RESUMO

For patients with citrullinemia type 1, nutritional management is essential to prevent the occurrence of complications associated with hyperammonemia. This report describes a patient who had been receiving nutrition intervention for more than 3 years. A newborn diagnosed with hyperammonemia due to citrullinemia visited Ajou University Hospital and was referred to the nutrition team. After receiving acute treatment, the infant was regularly fed with specialized formula. A protein-restricted diet is recommended for maintaining normal development and achieving long-term survival. Through continuous provision of nutritional intervention, the child showed normal growth and development, and the energy-protein supply was maintained appropriately. This case clearly shows the importance of medical nutrition therapy for patients with citrullinemia.

2.
Fitoterapia ; 152: 104921, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33984434

RESUMO

Accumulating evidence has shown an association between osteoporosis and oxidative damage. In the present study, the protective effects of diphlorethohydroxycarmalol (DPHC) isolated from the brown algae Ishige okamurae against H2O2-induced oxidative damage via bone morphogenetic protein 2 (BMP2)/ runt-related transcription factor 2 (Runx2) signaling were investigated using MC3T3-E1 osteoblastic cells. DPHC counteracted the reduction in cell viability caused by H2O2 exposure and protected against H2O2-induced dysfunction, demonstrated by improved cellular alkaline phosphatase (ALP) activity and calcium deposition. In addition, treatment with 0.05-0.2 mM DPHC elevated the protein expression of osteoblast differentiation factors type 1 collagen, ALP, p-Smad1/5, Osterix, BMP2, and Runx2, in response to H2O2-induced oxidative damage. Importantly, DPHC decreased the expression levels of receptor activator of nuclear factor kappa-B ligand, which promotes bone resorption, and inhibited the H2O2-induced generation of reactive oxygen species. Taken together, the results suggest that DPHC counteracts the effects of oxidative stress in osteoblastic cells and has the potential to be effective in preventing and alleviating osteoporosis.


Assuntos
Compostos Heterocíclicos com 3 Anéis/farmacologia , Osteoblastos/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Feófitas/química , Transdução de Sinais , Células 3T3 , Animais , Proteína Morfogenética Óssea 2 , Diferenciação Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Subunidade alfa 1 de Fator de Ligação ao Core , Compostos Heterocíclicos com 3 Anéis/isolamento & purificação , Peróxido de Hidrogênio , Camundongos , Estrutura Molecular , Espécies Reativas de Oxigênio/metabolismo , República da Coreia
3.
Foods ; 9(9)2020 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-32887356

RESUMO

For the functional food applications, antioxidant properties and the bioactive compounds of the 23 Curcuma species commercially cultivated in Thailand were studied. Total phenolic content and DPPH radical scavenging activity were determined. The concentrations of eight bioactive compounds, including curcumin (1), demethoxycurcumin (2), bisdemethoxycurcumin (3), 1,7-diphenyl-(4E,6E)-4,6-heptadien-3-ol (4), germacrone (5), furanodienone (6), zederone (7), and ar-turmerone (8), were determined from the Curcuma by HPLC. While the total phenolic content of C. longa was highest (22.3 ± 2.4 mg GAE/g, mg of gallic acid equivalents), C. Wan Na-Natong exhibited the highest DPPH (2,2-diphenyl-1-picryl-hydrazyl-hydrate) radical scavenging activity. Twenty-three Curcuma species showed characteristic distributions of the bioactive compounds, which can be utilized for the identification and authentication of the cultivated Curcuma species. C. longa contained the highest content of curcumin (1) (304.9 ± 0.1 mg/g) and C. angustifolia contained the highest content of germacrone (5) (373.9 ± 1.1 mg/g). It was noteworthy that 1,7-diphenyl-(4E,6E)-4,6-heptadien-3-ol (4) was found only from C. comosa at a very high concentration (300.7 ± 1.4 mg/g). It was concluded that Thai Curcuma species have a great potential for the application of functional foods and ingredients.

4.
Z Naturforsch C J Biosci ; 74(7-8): 167-174, 2019 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-31085751

RESUMO

Osteoporosis is one of the most common bone diseases, occurring due to an imbalance between bone formation and bone resorption. The aim of this study was to investigate the effects of Ishige sinicola, a brown alga, on osteoblast differentiation through the activation of the bone morphogenetic protein 2 (BMP-2)/runt-related transcription factor 2 (Runx2) signalling pathway in MC3T3-E1 cells. A cell proliferation assay, alkaline phosphatase (ALP) activity assay, alizarin red staining, and expression analysis of osteoblastic genes were carried out to assess MC3T3-E1 cell proliferation and osteoblastic differentiation. We found that I. sinicola extract (ISE) increased cell proliferation in a dose-dependent manner. Ishige sinicola extract markedly promoted ALP activity and mineralization. Alizarin red S staining demonstrated that ISE treatment tended to increase extracellular matrix calcium accumulation. Moreover, ISE up-regulated the osteoprotegerin/receptor activator of nuclear factor κB ligand ratio. Ishige sinicola extract also increased the protein expression levels of type 1 collagen, ALP, osteocalcin, osterix, BMP-2, and Runx2. Therefore, ISE showed potential in stimulating osteoblastic bone formation, and it might be useful for the prevention and treatment of osteoporosis.


Assuntos
Diferenciação Celular , Proliferação de Células , Osteoblastos/efeitos dos fármacos , Feófitas/química , Extratos Vegetais/farmacologia , Transdução de Sinais , Animais , Proteína Morfogenética Óssea 2/metabolismo , Cálcio/metabolismo , Linhagem Celular , Colágeno Tipo I/metabolismo , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Camundongos , NF-kappa B/metabolismo , Osteoblastos/citologia , Osteoblastos/metabolismo , Osteoblastos/fisiologia , Osteocalcina/metabolismo , Fator de Transcrição Sp7/metabolismo
5.
Molecules ; 23(7)2018 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-30041413

RESUMO

Whereas Korean ginseng, Panax ginseng Meyer, is harvested in the fall, the variation of ginsenoside content in field-grown ginseng across seasonal development has never been investigated in Korea. Thus, ultra-high performance liquid chromatography (UHPLC) analysis of nine major ginsenosides, including ginsenoside Rg1, Re, Rf, Rg2, Rb1, Rc, Rb2, Rd, and Ro, in the roots of five-year-old P. ginseng cultivated in Bongwha, Korea in 2017 was performed. The total ginsenoside content changed as many as three times throughout the year, ranging from 1.37 ± 0.02 (dry wt %) in January to 4.26 ± 0.03% in May. Total ginsenoside content in the harvest season was 2.49 ± 0.03%. Seasonal variations of panaxadiol-type ginsenosides (PPD) and panaxatriol-type ginsenosides (PPT) were found to be similar, but more PPD was always measured. However, the seasonal variation of oleanolic acid-type ginsenoside, Ro, was different from that of PPD and PPT, and the highest Ro content was observed in May. The ratio of PPD/PPT, as well as other representative ginsenosides, was compared throughout the year. Moreover, the percent composition of certain ginsenosides in both PPD and PPT types was found to be in a complementary relationship each other, which possibly reflected the biosynthetic pathway of the related ginsenosides. This finding would not only provide scientific support for the production and quality control of the value-added ginseng products, but also facilitate the elucidation of the ginsenoside biosynthetic pathway.


Assuntos
Vias Biossintéticas , Ginsenosídeos/biossíntese , Ginsenosídeos/química , Panax/química , Panax/metabolismo , Estações do Ano , Cromatografia Líquida de Alta Pressão , Estrutura Molecular , Raízes de Plantas/química , Raízes de Plantas/metabolismo , Fatores de Tempo
6.
J Agric Food Chem ; 65(16): 3305-3310, 2017 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-28401758

RESUMO

Curcumin and other curcuminoids from Curcuma longa are important bioactive compounds exhibiting various pharmacological activities. In addition to the known reductive metabolism of curcuminoids, an alternative biotransformation of curcuminoids by human gut microbiota is reported herein. A curcuminoid mixture, composed of curcumin (1), demethoxycurcumin (2), and bisdemethoxycurcumin (3), was metabolized by the human intestinal bacterium Blautia sp. MRG-PMF1. 1 and 2 were converted to new metabolites by the methyl aryl ether cleavage reaction. Two metabolites, demethylcurcumin (4) and bisdemethylcurcumin (5), were sequentially produced from 1, and demethyldemethoxycurcumin (6) was produced from 2. Until now, sequential reduction of the heptadienone backbone of curcuminoids was the only known metabolism to occur in the human intestine. In this study, a new intestinal metabolism of curcuminoids was discovered. Demethylation of curcuminoids produced three new colonic metabolites that were already known as promising synthetic curcumin analogues. The results could explain the observed beneficial effects of turmeric.


Assuntos
Bactérias/metabolismo , Curcuma/metabolismo , Curcumina/metabolismo , Microbioma Gastrointestinal , Mucosa Intestinal/metabolismo , Intestinos/microbiologia , Extratos Vegetais/metabolismo , Bactérias/classificação , Bactérias/isolamento & purificação , Curcumina/análogos & derivados , Curcumina/química , Diarileptanoides , Humanos , Metilação , Estrutura Molecular , Extratos Vegetais/química
7.
Phytochemistry ; 136: 9-14, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28139297

RESUMO

(E)-4-Hydroxy-3-methylbut-2-enyl diphosphate (HMBPP) reductase (IspH, HDR or LytB) is an Fe/S enzyme catalyzing the reductive dehydroxylation of HMBPP to isopentenyl diphosphate (IPP) and dimethylallyl diphosphate (DMAPP) in the last step of methylerythritol phosphate (MEP) pathway. The MEP pathway is known to produce 4-6:1 ratio of IPP and DMAPP mixture by the last enzyme, IspH. Plant IspH in plastids follows same catalytic mechanism as others, but GbIspH (Ginkgo biloba IspH) was reported to produce a mixture of IPP and DMAPP in a ratio of 16:1. Present catalytic mechanisms of IspH involve a common allyl anion intermediate, and the intramolecular proton transfer to the allyl moiety is considered as the key reaction step determining the product between IPP and DMAPP. The F212 residue in plant IspH was found as a potential amino acid residue that could mediate the proton transfer to the allyl anion intermediate before the product release. In this report, catalytic function of GbIspH F212 residue (H74 in E. coli), especially during the product formation in the active site, was studied by means of site-directed mutation. The product ratio of IPP/DMAPP was measured as 6.5 ± 0.1 for F212H GbIspH, and the value was close to the reported bacterial IspH having His residue on that specific position. Along with the other F212Y mutant, of which ratio was determined as 10.9 ± 0.1, the results strongly support that the Phe residue in plant IspH is the key amino acid residue that allows exclusive production of IPP in plant chloroplast.


Assuntos
Ginkgo biloba/química , Hemiterpenos/metabolismo , Compostos Organofosforados/metabolismo , Domínio Catalítico , Cloroplastos/metabolismo , Ginkgo biloba/metabolismo , Ferro/metabolismo , Dados de Sequência Molecular , Estrutura Molecular , Organofosfatos/metabolismo , Conformação Proteica , Estereoisomerismo , Sulfetos/metabolismo
8.
J Agric Food Chem ; 65(8): 1620-1629, 2017 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-28211698

RESUMO

Polymethoxyflavones (PMFs) were biotransformed to various demethylated metabolites in the human intestine by the PMF-metabolizing bacterium, Blautia sp. MRG-PMF1. Because the newly formed metabolites can have different biological activities, the pathways and regioselectivity of PMF bioconversion were investigated. Using an anaerobic in vitro study, 12 PMFs, 5,7-dimethoxyflavone (5,7-DMF), 5-hydroxy-7-methoxyflavone (5-OH-7-MF), 3,5,7-trimethoxyflavone (3,5,7-TMF), 5-hydroxy-3,7-dimethoxyflavone (5-OH-3,7-DMF), 5,7,4'-trimethoxyflavone (5,7,4'-TMF), 5-hydroxy-7,4'-dimethoxyflavone (5-OH-7,4'-DMF), 3,5,7,4'-tetramethoxyflavone (3,5,7,4'-TMF), 5-hydroxy-3,7,4'-trimethoxyflavone (5-OH-3,7,4'-TMF), 5,7,3',4'-tetramethoxyflavone (5,7,3',4'-TMF), 3,5,7,3',4'-pentamethoxyflavone (3,5,7,3',4'-PMF), 5-hydroxy-3,7,3',4'-tetramethoxyflavone (5-OH-3,7,3',4'-TMF), and 5,3'-dihydroxy-3,7,4'-trimethoxyflavone (5,3'-diOH-3,7,4'-TMF), were converted to chrysin, apigenin, galangin, kaempferol, luteolin, and quercetin after complete demethylation. The time-course monitoring of PMF biotransformations elucidated bioconversion pathways, including the identification of metabolic intermediates. As a robust flavonoid demethylase, regioselectivity of PMF demethylation generally followed the order C-7 > C-4' ≈ C-3' > C-5 > C-3. PMF demethylase in the MRG-PMF1 strain was suggested as a Co-corrinoid methyltransferase system, and this was supported by the experiments utilizing other methyl aryl ether substrates and inhibitors.


Assuntos
Firmicutes/metabolismo , Flavonoides/metabolismo , Microbioma Gastrointestinal , Intestinos/microbiologia , Biotransformação , Firmicutes/isolamento & purificação , Flavonoides/química , Humanos , Metilação
9.
Molecules ; 21(9)2016 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-27589718

RESUMO

Icariin is a major bioactive compound of Epimedii Herba, a traditional oriental medicine exhibiting anti-cancer, anti-inflammatory and anti-osteoporosis activities. Recently, the estrogenic activities of icariin drew significant attention, but the published scientific data seemed not to be so consistent. To provide fundamental information for the study of the icaritin metabolism, the biotransformation of icariin by the human intestinal bacteria is reported for the first time. Together with human intestinal microflora, the three bacteria Streptococcus sp. MRG-ICA-B, Enterococcus sp. MRG-ICA-E, and Blautia sp. MRG-PMF-1 isolated from human intestine were reacted with icariin under anaerobic conditions. The metabolites including icariside II, icaritin, and desmethylicaritin, but not icariside I, were produced. The MRG-ICA-B and E strains hydrolyzed only the glucose moiety of icariin, and icariside II was the only metabolite. However, the MRG-PMF-1 strain metabolized icariin further to desmethylicaritin via icariside II and icaritin. From the results, along with the icariin metabolism by human microflora, it was evident that most icariin is quickly transformed to icariside II before absorption in the human intestine. We propose the pharmacokinetics of icariin should focus on metabolites such as icariside II, icaritin and desmethylicaritin to explain the discrepancy between the in vitro bioassay and pharmacological effects.


Assuntos
Enterococcus/metabolismo , Flavonoides/metabolismo , Microbioma Gastrointestinal , Streptococcus/metabolismo , Anaerobiose/efeitos dos fármacos , Feminino , Flavonoides/farmacologia , Humanos , Masculino
10.
Nutr Res Pract ; 10(2): 148-53, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27087897

RESUMO

BACKGROUND/OBJECTIVES: Bone formation and bone resorption continuously occur in bone tissue to prevent the accumulation of old bone, this being called bone remodeling. Osteoblasts especially play a crucial role in bone formation through the differentiation and proliferation. Therefore, in this study, we investigated the effects of Scytosiphon lomentaria extract (SLE) on osteoblastic proliferation and differentiation in MC3T3-E1 cells. MATERIALS/METHODS: A cell proliferation assay, alkaline phosphatase (ALP) activity assay, alizarin red staining and protein expression analysis of osteoblastic genes were carried out to assess the osteoblastic proliferation and differentiation. RESULTS: The results indicated that treatment of SLE promoted the proliferation of MC3T3-E1 cells and improved ALP activity. And, SLE treatment significantly promoted mineralized nodule formation compared with control. In addition, cells treated with SLE significantly upregulated protein expression of ALP, type 1 collagen, bone morphogenetic protein 2, runt-related transcription factor 2, osterix, and osteoprotegerin. CONCLUSIONS: The results demonstrate that SLE promote differentiation inducement and proliferation of osteoblasts and, therefore may help to elucidate the transcriptional mechanism of bone formation and possibly lead to the development of bone-forming drugs.

11.
Z Naturforsch C J Biosci ; 71(1-2): 21-8, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26756092

RESUMO

Endothelial cell dysfunction is considered a major cause of vascular complications in diabetes. In the present study, we investigated the protective effect of daidzein, a natural isoflavonoid, against high-glucose-induced oxidative damage in human umbilical vein endothelial cells (HUVECs). Treatment with a high concentration of glucose (30 mM) induced oxidative stress in the endothelial cells, against which daidzein protected the cells as demonstrated by significantly increased cell viability. In addition, lipid peroxidation, intracellular reactive oxygen species (ROS) generation, and indirect nitric oxide levels induced by the high glucose treatment were significantly reduced in the presence of daidzein (0.02-0.1 mM) in a dose-dependent manner. High glucose levels induced the overexpression of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), and NF-κB proteins in HUVECs, which was suppressed by treatment with 0.04 mM daidzein. These findings indicate the potential of daidzein to reduce high glucose-induced oxidative stress.


Assuntos
Sobrevivência Celular/efeitos dos fármacos , Glucose/farmacologia , Isoflavonas/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Sobrevivência Celular/genética , Ciclo-Oxigenase 2/biossíntese , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Humanos , Peroxidação de Lipídeos/efeitos dos fármacos , NF-kappa B/biossíntese , Óxido Nítrico/biossíntese , Óxido Nítrico Sintase Tipo II/biossíntese , Estresse Oxidativo/genética , Espécies Reativas de Oxigênio/metabolismo
12.
J Sci Food Agric ; 96(3): 783-90, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25720987

RESUMO

BACKGROUND: Health problems related to the lack of bone formation are a major problem for ageing populations in the modern world. As a part of the ongoing trend to develop natural substances that attenuate bone loss in osteoporosis, the effects of the edible brown alga Sargassum thunbergii and its active contents on adipogenic differentiation in 3T3-L1 fibroblasts and osteoblast differentiation in MC3T3-E1 pre-osteoblasts were evaluated. RESULTS: Treatment with S. thunbergii significantly reduced lipid accumulation and expression of adipogenic differentiation markers such as peroxisome proliferator-activated receptor γ, CCAAT/enhancer-binding protein α and sterol regulatory element binding protein 1c. In addition, S. thunbergii successfully enhanced osteoblast differentiation as indicated by increased alkaline phosphatase activity along raised levels of osteoblastogenesis indicators, namely bone morphogenetic protein-2, osteocalcin and collagen type I. Two compounds, sargaquinoic and sargahydroquinoic acid, were isolated from active extract and shown to be active by means of osteogenesis inducement. CONCLUSION: S. thunbergii could be a source for functional food ingredients for improved treatment of osteoporosis and obesity.


Assuntos
Adipogenia/efeitos dos fármacos , Osteoblastos/fisiologia , Osteogênese/efeitos dos fármacos , Quinonas/farmacologia , Sargassum/química , Células 3T3-L1 , Alcenos/isolamento & purificação , Alcenos/farmacologia , Animais , Benzoquinonas/isolamento & purificação , Benzoquinonas/farmacologia , Proteína alfa Estimuladora de Ligação a CCAAT/análise , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Lipídeos/análise , Camundongos , PPAR gama/análise , Proteína de Ligação a Elemento Regulador de Esterol 1/análise
13.
Arch Pharm Res ; 38(12): 2172-82, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26202444

RESUMO

Osteoporosis, a prevalent bone disease in an aging population, is considered to be closely related to osteoblastogenesis and adipogenesis. As a part of an ongoing trend to develop natural substances that attenuate osteoporotic conditions, edible brown algae E. cava and its bioactive constituents were tested for their effects on adipogenic differentiation in 3T3-L1 fibroblasts and osteoblast differentiation in MC3T3-E1 pre-osteoblasts. Following an activity-based isolation, three phlorotannin derivatives, triphlorethol-A (1), eckol (2) and dieckol (3), were isolated. Anti-adipogenesis effect of phlorotannins at the concentration of 20 µM was observed by reduced lipid accumulation and the suppressed expression of adipogenic differentiation markers. In addition, isolated phlorotannins successfully enhanced the osteoblast differentiation as indicated by increased alkaline phosphatase activity along with raised levels of osteoblastogenesis indicators and intracellular calcification at the concentration of 20 µM. In conclusion, E. cava is suggested as a source for functional food ingredients, especially phlorotannin derivatives that can be utilized for extenuating osteoporosis and obesity.


Assuntos
Adipócitos/efeitos dos fármacos , Adipogenia/efeitos dos fármacos , Osteoblastos/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Feófitas , Taninos/farmacologia , Células 3T3-L1 , Adipócitos/fisiologia , Adipogenia/fisiologia , Animais , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/fisiologia , Relação Dose-Resposta a Droga , Camundongos , Osteoblastos/fisiologia , Osteogênese/fisiologia , Taninos/química , Taninos/isolamento & purificação
14.
J Microbiol Biotechnol ; 25(9): 1442-8, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25975614

RESUMO

The flavonoid apigenin and its O-methyl derivative, genkwanin, have various biological activities and can be sourced from some vegetables and fruits. Microorganisms are an alternative for the synthesis of flavonoids. Here, to synthesize genkwanin from tyrosine, we first synthesized apigenin from p-coumaric acid using four genes (4CL, CHS, CHI, and FNS) in Escherichia coli. After optimization of different combinations of constructs, the yield of apigenin was increased from 13 mg/l to 30 mg/l. By introducing two additional genes (TAL and POMT7) into an apigenin-producing E. coli strain, we were able to synthesize 7-O-methyl apigenin (genkwanin) from tyrosine. In addition, the tyrosine content in E. coli was modulated by overexpressing aroG and tyrA. The engineered E. coli strain synthesized approximately 41 mg/l genkwanin.


Assuntos
Apigenina/biossíntese , Escherichia coli/genética , Escherichia coli/metabolismo , Flavonas/biossíntese , Engenharia Metabólica/métodos , Biotransformação , Ácidos Cumáricos/metabolismo , Redes e Vias Metabólicas/genética , Propionatos , Tirosina/metabolismo
15.
J Sci Food Agric ; 95(9): 1925-31, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25199800

RESUMO

BACKGROUND: Plant isoflavones are mostly present in the glycoside form. Isoflavone aglycones produced by intestinal microflora are reported to be more bioactive than the glycoside form. However, the deglycosylation of isoflavone C-glycosides is known to be rare, and is less studied. RESULTS: Three new bacteria were isolated from human faecal samples, two of which hydrolysed the C-glycosidic bond of puerarin, daidzein-8-C-glucoside. They were identified as two Lactococcus species, herein designated as MRG-IFC-1 and MRG-IFC-3, and an Enterococcus species, herein designated MRG-IFC-2, based on their 16S rDNA sequences. From a reactivity study, it was found that Lactococcus sp. MRG-IFC-1 and Enterococcus sp. MRG-IFC-2 hydrolysed isoflavone C- and O-glycosides, as well as the flavone O-glycoside apigetrin, but could not hydrolyse the flavone C-glycosidic bond of vitexin. The other Lactococcus sp., MRG-IF-3, could not hydrolyse the C-glycosidic linkage of puerarin, while it showed a broad substrate spectrum of O-glycosidase activity similar to the other two bacteria. Puerarin was completely converted to daidzein within 100 min by Lactococcus sp. MRG-IFC-1 and Enterococcus sp. MRG-IFC-2, which is the fastest conversion among the reported human intestinal bacteria. CONCLUSION: Two new puerarin-metabolising human intestinal bacteria were isolated and identified, and the deglycosylation activity for various flavonoid glycosides was investigated. The results could facilitate the study of C-glycosidase reaction mechanisms, as well as the pharmacokinetics of bioactive C-glycoside natural products.


Assuntos
Proteínas de Bactérias/metabolismo , Enterococcus/metabolismo , Glicosídeo Hidrolases/metabolismo , Glicosídeos/metabolismo , Intestinos/microbiologia , Isoflavonas/metabolismo , Lactococcus/metabolismo , Adulto , Apigenina/metabolismo , Enterococcus/classificação , Enterococcus/isolamento & purificação , Fezes/microbiologia , Feminino , Microbioma Gastrointestinal , Glicosilação , Humanos , Hidrólise , Cinética , Lactococcus/classificação , Lactococcus/isolamento & purificação , Tipagem Molecular , República da Coreia , Especificidade por Substrato
16.
J Agric Food Chem ; 62(51): 12377-83, 2014 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-25437273

RESUMO

Poylmethoxyflavones (PMFs) are major bioactive flavonoids, which exhibit various biological activities, such as anticancer effects. The biotransformation of PMFs and characterization of a PMF-metabolizing human intestinal bacterium were studied herein for the first time. Hydrolysis of aryl methyl ether functional groups by human fecal samples was observed from the bioconversion of various PMFs. Activity-guided screening for PMF-metabolizing intestinal bacteria under anaerobic conditions resulted in the isolation of a strict anaerobic bacterium, which was identified as Blautia sp. MRG-PMF1. The isolated MRG-PMF1 was able to metabolize various PMFs to the corresponding demethylated flavones. The microbial conversion of bioactive 5,7-dimethoxyflavone (5,7-DMF) and 5,7,4'-trimethoxyflavone (5,7,4'-TMF) was studied in detail. 5,7-DMF and 5,7,4'-TMF were completely metabolized to 5,7-dihydroxyflavone (chrysin) and 5,7,4'-trihydroxyflavone (apigenin), respectively. From a kinetics study, the methoxy group on the flavone C-7 position was found to be preferentially hydrolyzed. 5-Methoxychrysin, the intermediate of 5,7-DMF metabolism by Blautia sp. MRG-PMF1, was isolated and characterized by nuclear magnetic resonance spectroscopy. Apigenin was produced from the sequential demethylation of 5,7,4'-TMF, via 5,4'-dimethoxy-7-hydroxyflavone and 7,4'-dihydroxy-5-methoxyflavone (thevetiaflavone). Not only demethylation activity but also deglycosylation activity was exhibited by Blautia sp. MRG-PMF1, and various flavonoids, including isoflavones, flavones, and flavanones, were found to be metabolized to the corresponding aglycones. The unprecedented PMF demethylation activity of Blautia sp. MRG-PMF1 will expand our understanding of flavonoid metabolism in the human intestine and lead to novel bioactive compounds.


Assuntos
Bactérias/metabolismo , Flavonas/metabolismo , Intestinos/microbiologia , Zingiberaceae/metabolismo , Bactérias/genética , Bactérias/isolamento & purificação , Flavonas/química , Humanos , Mucosa Intestinal/metabolismo , Cinética , Estrutura Molecular , Extratos Vegetais/química , Extratos Vegetais/metabolismo
17.
Prev Nutr Food Sci ; 19(3): 187-93, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25320716

RESUMO

For decades, Spergularia marina, a local food that is popular in South Korea, has been regarded as a nutritious source of amino acids, vitamins, and minerals. While several halophytes are reported to possess distinct bioactivities, S. marina has yet to be promoted as a natural source of bioactives. In this study, the effects of S. marina on the adipogenic differentiation of 3T3-L1 fibroblasts and the osteoblastic differentiation of MC3T3-E1 pre-osteoblasts and C2C12 myoblast cells were evaluated. The anti-adipogenic effect of S. marina was assessed by measuring lipid accumulation and adipogenic differentiation marker expression. S. marina treatment significantly reduced lipid accumulation and notably decreased the gene levels of peroxisome proliferator-activated receptor γ, CCAAT/enhancer-binding protein α, and sterol regulatory element binding protein 1c. In addition, S. marina enhanced osteoblast differentiation, as indicated by increased alkaline phosphatase activity and increased levels of osteoblastogenesis indicators, namely bone morphogenetic protein-2, osteocalcin, and type I collagen. In conclusion, S. marina could be a source of functional food ingredients that improve osteoporosis and obesity. Further studies, including activity-based fractionation, will elucidate the mechanism of action and active ingredients of S. marina, which would provide researchers with a better understanding of the nutraceutical and therapeutic applications of S. marina.

18.
Chirality ; 26(9): 434-7, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24519947

RESUMO

To elucidate the hitherto unknown absolute configuration of (-)-O-desmethylangolensin ((-)-O-DMA), an intestinal bacterial metabolite produced from daidzein, chiroptical study, including specific optical rotation and electronic circular dichroism (ECD), of (R)-O-DMA was carried out by Time-Dependent Density Functional Theory (TD-DFT) calculations. Intramolecular hydrogen bonding between 2'-OH and carbonyl oxygen at 1-C of O-DMA was a governing factor for O-DMA to form the stable conformations. Total energy values of four possible conformers were calculated in the framework of DFT using the B3LYP exchange correlation functional at the 6-31++G basis set level. The theoretical specific rotation and ECD spectra of all conformers in ethanol were obtained by TD-DFT calculation using B3LYP functional at the 6-311++G basis set level, and compared to the experimental data. Chiroptical properties of (R)-O-DMA showed a good agreement with the biological (-)-O-DMA. Therefore, the stereospecific biosynthetic pathway of (-)-O-DMA was proposed as daidzein → (R)-dihydrodaidzein ↔ (S)-dihydrodaizein → (R)-O-DMA.

19.
Planta ; 238(4): 683-93, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23801300

RESUMO

Flavonoids are predominantly found as glycosides in plants. The glycosylation of flavonoids is mediated by uridine diphosphate-dependent glycosyltransferases (UGT). UGTs attach various sugars, including arabinose, glucose, galactose, xylose, and glucuronic acid, to flavonoid aglycones. Two UGTs isolated from Arabidopsis thaliana, AtUGT78D2 and AtUGT78D3, showed 89 % amino acid sequence similarity (75 % amino acid sequence identity) and both attached a sugar to the 3-hydroxyl group of flavonols using a UDP-sugar. The two enzymes used UDP-glucose and UDP-arabinose, respectively, and AtUGT78D2 was approximately 90-fold more efficient than AtUGT78D3 when judged by the k(cat)/K(m) value. Domain exchanges between AtUGT78D2 and AtUGT78D3 were carried out to find UGTs with better catalytic efficiency for UDP-arabinose and exhibiting dual sugar selectivity. Among 19 fusion proteins examined, three showed dual sugar selectivity, and one fusion protein had better catalytic efficiency for UDP-arabinose compared with AtUGT78D3. Using molecular modeling, the changes in enzymatic properties in the chimeric proteins were elucidated. To the best of our knowledge, this is the first report on the construction of fusion proteins with expanded sugar-donor range and enhanced catalytic efficiencies for sugar donors.


Assuntos
Proteínas de Arabidopsis/genética , Arabidopsis/genética , Glicosiltransferases/genética , Uridina Difosfato Glucose/metabolismo , Açúcares de Uridina Difosfato/metabolismo , Sequência de Aminoácidos , Domínio Catalítico/genética , Modelos Moleculares , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Proteínas Recombinantes de Fusão/genética , Especificidade por Substrato/genética , Uridina Difosfato Glucose/genética , Açúcares de Uridina Difosfato/genética
20.
Phytochemistry ; 76: 25-31, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22285622

RESUMO

Hydroxycinnamoyltransferases (HCTs) catalyze the transfer of the cinnamoyl moiety from hydroxycinnamoyl-CoA to various acceptors such as shikimic acid, quinic acid, hydroxylated acid, and glycerol. Four rice HCT homologues (OsHCT1-4) to tobacco HST were cloned, and OsHCT4 was expressed in Escherichia coli as a glutathione S-transferase fusion protein. Using the purified recombinant protein and biotransformation techniques, whether OsHCT4 shows hydroxycinnamoyltransferase activity with a variety of acyl group acceptors was investigated. The results of high performance liquid chromatography (HPLC) and mass spectrometry (MS) established that OsHCT4 mediated the trans-esterification of glycerol as well as shikimic acid in the presence of hydroxycinnamoyl-CoA. The structure of the reaction product was determined using nuclear magnetic resonance spectroscopy (NMR). E. coli cells co-expressing 4CL (4-coumarate:coenzyme A ligase) and OsHCT4 converted p-coumaric acid, ferulic acid, and caffeic acid into the corresponding glycerides. While this conversion is very efficient in vitro, the physiological significant in rice is currently unknown.


Assuntos
Aciltransferases/química , Ácidos Cumáricos/química , Glicerol/química , Oryza/enzimologia , Acil Coenzima A/química , Aciltransferases/classificação , Aciltransferases/genética , Ácidos Cafeicos/química , Cromatografia Líquida de Alta Pressão , Clonagem Molecular , Coenzima A-Transferases/química , Coenzima A-Transferases/classificação , Coenzima A-Transferases/genética , Ensaios Enzimáticos , Escherichia coli/química , Escherichia coli/genética , Esterificação , Genes de Plantas , Glutationa Transferase/química , Glicerídeos/química , Glicerol/análogos & derivados , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Oryza/química , Oryza/genética , Filogenia , Proteínas de Plantas/química , Proteínas de Plantas/genética , RNA de Plantas/genética , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/isolamento & purificação , Ácido Chiquímico/química , Especificidade por Substrato , Transformação Genética
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