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1.
J Microbiol Biotechnol ; 32(12): 1573-1582, 2022 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-36398443

RESUMO

In this study, we investigated the optimal conditions for 3D structure printing of alternative fats that have the textural properties of lard using beeswax (BW)-based oleogel by a statistical analysis. Products printed with over 15% BW oleogel at 50% and 75% infill level (IL) showed high printing accuracy with the lowest dimensional printing deviation for the designed model. The hardness, cohesion, and adhesion of printed samples were influenced by BW concentration and infill level. For multi-response optimization, fixed target values (hardness, adhesiveness, and cohesiveness) were applied with lard printed at 75% IL. The preparation parameters obtained as a result of multiple reaction prediction were 58.9% IL and 16.0% BW, and printing with this oleogel achieved fixed target values similar to those of lard. In conclusion, our study shows that 3D printing based on the BW oleogel system produces complex internal structures that allow adjustment of the textural properties of the printed samples, and BW oleogels could potentially serve as an excellent replacement for fat.


Assuntos
Impressão Tridimensional , Ceras , Ceras/química
2.
J Microbiol Biotechnol ; 30(11): 1706-1719, 2020 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-32830188

RESUMO

The objective of this study was to optimize the conditions for enhancing the antioxidant properties of sword bean (Canavalia gladiata) as a coffee substitute in two processing methods, roasting and grinding. The optimum conditions for removing off-flavor of the bean and maximizing functionality and efficiency were light roasting and cryogenic grinding (< 53 µm). In these conditions, extraction yield was 16.75%, total phenolic content (TPC) was 69.82 ± 0.35 mg gallic acid equivalents/g, and total flavonoid content (TFC) was 168.81 ± 1.64 mg quercetin equivalents/100 g. The antioxidant properties were 77.58 ± 0.27% for DPPH radical scavenging activity and 58.02 ± 0.76 mg Trolox equivalents/g for ABTS radical scavenging activity. The values for TFC and ABTS radical scavenging activity were significantly higher (p < 0.05) than in other conditions, and TPC and DPPH radical scavenging activity were second highest in lightly roasted beans, following raw beans. HS-SPME/GCMS analysis confirmed that the amino acids and carbohydrates, which are the main components of sword bean, were condensed into other volatile flavor compounds, such as derivatives of furan, pyrazine, and pyrrole during roasting. Roasted and cryogenically ground (cryo-ground) sword beans showed higher functionality in terms of TFC, DPPH, and ABTS radical scavenging activities compared to those of coffee. Overall results showed that light roasting and cryogenic grinding are the most suitable processing conditions for enhancing the bioactivity of sword beans.


Assuntos
Antioxidantes/análise , Canavalia/química , Extratos Vegetais/química , Café/química , Flavonoides/análise , Manipulação de Alimentos/métodos , Ácido Gálico , Temperatura Alta , Tamanho da Partícula , Fenóis/análise , Sementes/química
3.
Syst Appl Microbiol ; 43(3): 126085, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32381322

RESUMO

Two extremely halophilic archaea strains, CBA1112T and CBA1113, were isolated from solar salt in Korea. The genome sizes and G+C content of CBA1112T and CBA1113 were 3.77 and 3.53Mb, and 66.0 and 66.5mol%, respectively. Phylogenetic analysis based on closely related taxa and environmental Haloplanus sequences indicated that both CBA1112T and CBA1113 strains are grouped within the genus Haloplanus. OrthoANI and in silico DNA-DNA hybridization values were below the species delineation threshold. Pan-genomic analysis showed that the two novel strains and four reference strains had 6203 pan-orthologous groups in total. Six Haloplanus strains shared 1728 core pan-genome orthologous groups, which were mainly associated with amino acid transport and metabolism and translation, ribosomal structure and biogenesis categories, and amino acid metabolism and carbohydrate metabolism related categories. The novel strain-specific pan-genome orthologous groups were mainly involved with replication, recombination and repair category and replication and repair pathway or amino acid metabolism pathway. Cells of both strains were Gram-negative and pleomorphic, and colonies were red-pigmented. The major polar lipids of both strains were phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester, phosphatidylglycerol sulfate, and one glycolipid, sulfated mannosyl glucosyl diether. Based on genomic, phylogenetic, phenotypic, and chemotaxonomic features, strains CBA1112T and CBA1113 are described as novel species of the genus Haloplanus. Thus, we propose the name Haloplanus rubicundus sp. nov. The type strain is CBA1112T (=KCCM 43224T=JCM 30475T).


Assuntos
Halobacteriaceae/classificação , Halobacteriaceae/genética , Técnicas de Tipagem Bacteriana , Composição de Bases , Biblioteca Gênica , Genoma Arqueal , Genômica/métodos , Halobacteriaceae/isolamento & purificação , Fenótipo , Filogenia , RNA Ribossômico 16S/genética
4.
Molecules ; 22(10)2017 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-28981451

RESUMO

Glycol chitosan (GC) and its derivatives have been extensively investigated as safe and effective drug delivery carriers because of their unique physiochemical and biological properties. The reactive functional groups such as the amine and hydroxyl groups on the GC backbone allow for easy chemical modification with various chemical compounds (e.g., hydrophobic molecules, crosslinkers, and acid-sensitive and labile molecules), and the versatility in chemical modifications enables production of a wide range of GC-based drug carriers. This review summarizes the versatile chemical modification methods that can be used to design GC-based drug carriers and describes their recent applications in disease therapy.


Assuntos
Quitosana/química , Portadores de Fármacos/química , Nanopartículas/química , Animais , Antineoplásicos/administração & dosagem , Reagentes de Ligações Cruzadas/química , Terapia Genética/métodos , Humanos , Interações Hidrofóbicas e Hidrofílicas , Estrutura Molecular , Fotoquimioterapia/métodos
5.
Int J Syst Evol Microbiol ; 66(7): 2740-2746, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27118259

RESUMO

A novel halophilic archaeon designated strain CBA1114T was isolated from solar salt in the Republic of Korea. Strain CBA1114T, cells of which were coccoid and Gram-stain-negative, grew in the presence of 15-30 % (w/v) NaCl (optimum, 20 %) and at 20-50 °C (optimum, 40 °C) and pH 7.0-9.0 (optimum, pH 8.0). Strain CBA1114T required Mg2+ for growth. Strain CBA1114T had three 16S rRNA genes, rrnA, rrnB and rrnC; levels of similarity between the sequences were 99.7-99.9 %. The 16S rRNA gene sequence of strain CBA1114T showed 91.7 % similarity to that of Haloterrigena thermotolerans PR5T. In multilocus sequence analysis (MLSA), five housekeeping genes, atpB, EF-2, radA, rpoB' and secY, were found to be closely related to those of the members of the genera Halorientalis(89.7 % similarity of the atpB gene sequence), Halomicroarcula(91.9 %, EF-2), Haloterrigena(85.4 %, radA), Natronoarchaeum(89.2 %, rpoB') and Natrinema(75.7 %, secY). A phylogenetic tree generated from the results of MLSA of the five housekeeping genes showed that strain CBA1114T was closely related to species of the genus Halorientalis in the family Halobacteriaceae. The major polar lipids were identified as phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester and unidentified lipids. The G+C content of the genomic DNA of strain CBA1114T was 68.1 mol%. According to the results of phylogenetic, phenotypic and chemotaxonomic analyses, we designate strain CBA1114T (=JCM 30111T=KCTC 4206T) as the type strain of Halostella salina gen. nov., sp. nov., a novel species of a new genus within the family Halobacteriaceae.


Assuntos
Halobacteriaceae/classificação , Filogenia , Cloreto de Sódio , Composição de Bases , DNA Arqueal/genética , Genes Arqueais , Halobacteriaceae/genética , Halobacteriaceae/isolamento & purificação , Tipagem de Sequências Multilocus , Fosfolipídeos/química , RNA Ribossômico 16S/genética , República da Coreia , Análise de Sequência de DNA
6.
Food Chem ; 201: 315-9, 2016 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-26868582

RESUMO

Although fruit juices are very popular, enzymatic browning occurs easily. Browning of fruit juice deteriorates nutrition value and product quality due to oxidation of polyphenol compounds. Therefore, development of natural food additives that reduce browning will be beneficial for improving quality of fruit juices. Onion has been reported to be a potent natural anti-browning agent. Here, we compared unheated and heated apple juices pre-supplemented with onion with respect to browning and nutritional quality. The unheated apple juice supplemented with onion showed reduced browning as well as increased total soluble solid, total phenol concentration, radical scavenging activities, and ferric reducing and copper chelating activities without any change in flavonoid concentration. On the other hand, heated juice supplemented with onion not only showed improved values for these parameters but also markedly increased flavonoid concentration. Thus, we conclude that application of heating and onion addition together may greatly improve quality of apple juice.


Assuntos
Bebidas/análise , Frutas/química , Malus/química , Valor Nutritivo , Cebolas/química , Antioxidantes , Flavonoides , Temperatura Alta
7.
PLoS One ; 10(8): e0136728, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26322642

RESUMO

The emergence of compensatory mutations in the polymerase gene of drug resistant hepatitis B virus (HBV) is associated with treatment failure. We previously identified a multi-drug resistant HBV mutant, which displayed resistance towards lamivudine (LMV), clevudine (CLV), and entecavir (ETV), along with a strong replication capacity. The aim of this study was to identify the previously unknown compensatory mutations, and to determine the clinical relevance of this mutation during antiviral therapy. In vitro mutagenesis, drug susceptibility assay, and molecular modeling studies were performed. The rtL269I substitution conferred 2- to 7-fold higher replication capacity in the wild-type (WT) or YMDD mutation backbone, regardless of drug treatment. The rtL269I substitution alone did not confer resistance to LMV, ETV, adefovir (ADV), or tenofovir (TDF). However, upon combination with YMDD mutation, the replication capacity under LMV or ETV treatment was enhanced by several folds. Molecular modeling studies suggested that the rtL269I substitution affects template binding, which may eventually lead to the enhanced activity of rtI269-HBV polymerase in both WT virus and YMDD mutant. The clinical relevance of the rtL269I substitution was validated by its emergence in association with YMDD mutation in chronic hepatitis B (CHB) patients with sub-optimal response or treatment failure to LMV or CLV. Our study suggests that substitution at rt269 in HBV polymerase is associated with multi-drug resistance, which may serve as a novel compensatory mutation for replication-defective multi-drug resistant HBV.


Assuntos
Antivirais/uso terapêutico , Farmacorresistência Viral Múltipla/genética , Produtos do Gene pol/genética , Vírus da Hepatite B/efeitos dos fármacos , Vírus da Hepatite B/genética , Adenina/análogos & derivados , Adenina/uso terapêutico , Substituição de Aminoácidos/genética , Arabinofuranosiluracila/análogos & derivados , Arabinofuranosiluracila/uso terapêutico , Linhagem Celular Tumoral , Guanina/análogos & derivados , Guanina/farmacologia , Antígenos de Superfície da Hepatite B/metabolismo , Antígenos E da Hepatite B/metabolismo , Hepatite B Crônica/tratamento farmacológico , Hepatite B Crônica/virologia , Humanos , Lamivudina/uso terapêutico , Testes de Sensibilidade Microbiana , Modelos Moleculares , Organofosfonatos/uso terapêutico , Tenofovir/uso terapêutico , Replicação Viral/efeitos dos fármacos
8.
J Microbiol Biotechnol ; 25(5): 637-47, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25563422

RESUMO

In this study, we attempted to understand signaling pathways behind lipid biosynthesis by employing a chemical genetics approach based on small molecule inhibitors. Specific signaling inhibitors of MAP kinase or modulators of cAMP signaling were selected to evaluate the functional roles of each of the key signaling pathways in three different microalgal species: Chlamydomonas reinhardtii, Chlorella vulgaris, and Haematococcus pluvialis. Our results clearly indicate that cAMP signaling pathways are indeed positively associated with microalgal lipid biosynthesis. In contrast, MAP kinase pathways in three microalgal species are all negatively implicated in both lipid and carotenoid biosynthesis.


Assuntos
Carotenoides/biossíntese , Chlamydomonas reinhardtii/química , Chlamydomonas reinhardtii/metabolismo , AMP Cíclico/metabolismo , Lipídeos/biossíntese , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Carotenoides/análise , Glucose/metabolismo , Lipídeos/análise , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/fisiologia
9.
Int J Syst Evol Microbiol ; 65(Pt 1): 201-205, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25323594

RESUMO

An anaerobic, rod-shaped, hyperthermophilic and acidophilic crenarchaeon, designated strain CBA1501(T), was isolated from solfataric soil of the Mayon volcano in the Republic of the Philippines. Phylogenetic analysis showed that strain CBA1501(T) is affiliated with the genus Vulcanisaeta in the phylum Crenarchaeota. DNA sequence similarities between the 16S rRNA gene of strain CBA1501(T) and those of Vulcanisaeta distributa IC-017(T) and Vulcanisaeta souniana IC-059(T) were 98.5 and 97.4 %, respectively. Strain CBA1501(T) grew between 75-90 °C, over a pH range of 4.0-6.0 and in the presence of 0-1.0 % (w/v) NaCl, with optimal growth occurring at 85 °C, pH 5.0, and with 0 % (w/v) NaCl. Fumarate, malate, oxidized glutathione, sulfur and thiosulfate were used as final electron acceptors, but FeCl3, nitrate and sulfate were not. The DNA G+C content of strain CBA1501(T) was 43.1 mol%. On the basis of polyphasic taxonomic analysis, strain CBA1501(T) represents a novel species of the genus Vulcanisaeta in the phylum Crenarchaeota, for which we propose the name Vulcanisaeta thermophila sp. nov. The type strain is CBA1501(T) ( = ATCC BAA-2415(T) = JCM 17228(T)).


Assuntos
Crenarchaeota/classificação , Filogenia , Microbiologia do Solo , Composição de Bases , Crenarchaeota/genética , Crenarchaeota/isolamento & purificação , DNA Arqueal/genética , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , Filipinas , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
10.
Mar Drugs ; 12(12): 6038-57, 2014 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-25522316

RESUMO

Theranostics is an integrated nanosystem that combines therapeutics with diagnostics in attempt to develop new personalized treatments with enhanced therapeutic efficacy and safety. As a promising therapeutic paradigm with cutting-edge technologies, theranostic agents are able to simultaneously deliver therapeutic drugs and diagnostic imaging agents and also monitor the response to therapy. Polymeric nanosystems have been intensively explored for biomedical applications to diagnose and treat various cancers. In recent years, glycol chitosan-based nanoagents have been developed as dual-purpose materials for simultaneous diagnosis and therapy. They have shown great potential in cancer therapies, such as chemotherapeutics and nucleic acid and photodynamic therapies. In this review, we summarize the recent progress and potential applications of glycol chitosan-based fluorescent theranostic nanoagents for cancer treatments and discuss their possible underlying mechanisms.


Assuntos
Quitosana/farmacologia , Quitosana/uso terapêutico , Corantes Fluorescentes/farmacologia , Corantes Fluorescentes/uso terapêutico , Nanopartículas/uso terapêutico , Neoplasias/tratamento farmacológico , Animais , Diagnóstico por Imagem/métodos , Humanos
11.
Proc Natl Acad Sci U S A ; 111(34): 12556-61, 2014 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-25114221

RESUMO

In a fluorescence polarization screen for the MYC-MAX interaction, we have identified a novel small-molecule inhibitor of MYC, KJ-Pyr-9, from a Kröhnke pyridine library. The Kd of KJ-Pyr-9 for MYC in vitro is 6.5 ± 1.0 nM, as determined by backscattering interferometry; KJ-Pyr-9 also interferes with MYC-MAX complex formation in the cell, as shown in a protein fragment complementation assay. KJ-Pyr-9 specifically inhibits MYC-induced oncogenic transformation in cell culture; it has no or only weak effects on the oncogenic activity of several unrelated oncoproteins. KJ-Pyr-9 preferentially interferes with the proliferation of MYC-overexpressing human and avian cells and specifically reduces the MYC-driven transcriptional signature. In vivo, KJ-Pyr-9 effectively blocks the growth of a xenotransplant of MYC-amplified human cancer cells.


Assuntos
Antineoplásicos/farmacologia , Proteínas Proto-Oncogênicas c-myc/antagonistas & inibidores , Piridinas/farmacologia , Pirimidinas/farmacologia , Animais , Antineoplásicos/química , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/antagonistas & inibidores , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/química , Proliferação de Células/efeitos dos fármacos , Transformação Celular Neoplásica/efeitos dos fármacos , Transformação Celular Neoplásica/genética , Células Cultivadas , Embrião de Galinha , Avaliação Pré-Clínica de Medicamentos , Feminino , Polarização de Fluorescência , Genes myc , Humanos , Interferometria , Camundongos , Camundongos Nus , Complexos Multiproteicos/antagonistas & inibidores , Complexos Multiproteicos/química , Domínios e Motivos de Interação entre Proteínas/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-myc/química , Piridinas/química , Pirimidinas/química , Ensaios Antitumorais Modelo de Xenoenxerto
12.
J Virol ; 88(19): 11240-52, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25031343

RESUMO

UNLABELLED: Hepatitis C virus (HCV) nonstructural protein 5B (NS5B), an RNA-dependent RNA polymerase (RdRp), is the key enzyme for HCV RNA replication. We previously showed that HCV RdRp is phosphorylated by protein kinase C-related kinase 2 (PRK2). In the present study, we used biochemical and reverse-genetics approaches to demonstrate that HCV NS5B phosphorylation is crucial for viral RNA replication in cell culture. Two-dimensional phosphoamino acid analysis revealed that PRK2 phosphorylates NS5B exclusively at its serine residues in vitro and in vivo. Using in vitro kinase assays and mass spectrometry, we identified two phosphorylation sites, Ser29 and Ser42, in the Δ1 finger loop region that interacts with the thumb subdomain of NS5B. Colony-forming assays using drug-selectable HCV subgenomic RNA replicons revealed that preventing phosphorylation by Ala substitution at either Ser29 or Ser42 impairs HCV RNA replication. Furthermore, reverse-genetics studies using HCV infectious clones encoding phosphorylation-defective NS5B confirmed the crucial role of these PRK2 phosphorylation sites in viral RNA replication. Molecular-modeling studies predicted that the phosphorylation of NS5B stabilizes the interactions between its Δ1 loop and thumb subdomain, which are required for the formation of the closed conformation of NS5B known to be important for de novo RNA synthesis. Collectively, our results provide evidence that HCV NS5B phosphorylation has a positive regulatory role in HCV RNA replication. IMPORTANCE: While the role of RNA-dependent RNA polymerases (RdRps) in viral RNA replication is clear, little is known about their functional regulation by phosphorylation. In this study, we addressed several important questions about the function and structure of phosphorylated hepatitis C virus (HCV) nonstructural protein 5B (NS5B). Reverse-genetics studies with HCV replicons encoding phosphorylation-defective NS5B mutants and analysis of their RdRp activities revealed previously unidentified NS5B protein features related to HCV replication and NS5B phosphorylation. These attributes most likely reflect potential structural changes induced by phosphorylation in the Δ1 finger loop region of NS5B with two identified phosphate acceptor sites, Ser29 and Ser42, which may transiently affect the closed conformation of NS5B. Elucidating the effects of dynamic changes in NS5B phosphorylation status during viral replication and their impacts on RNA synthesis will improve our understanding of the molecular mechanisms of NS5B phosphorylation-mediated regulation of HCV replication.


Assuntos
Regulação Viral da Expressão Gênica , Hepacivirus/genética , Proteína Quinase C/genética , RNA Polimerase Dependente de RNA/genética , Serina/metabolismo , Proteínas não Estruturais Virais/genética , Replicação Viral , Sequência de Aminoácidos , Linhagem Celular Tumoral , Hepacivirus/metabolismo , Hepatócitos/metabolismo , Hepatócitos/virologia , Humanos , Modelos Moleculares , Dados de Sequência Molecular , Fosforilação , Proteína Quinase C/metabolismo , Estrutura Secundária de Proteína , Estrutura Terciária de Proteína , RNA Polimerase Dependente de RNA/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Serina/genética , Proteínas não Estruturais Virais/química , Proteínas não Estruturais Virais/metabolismo
13.
FEMS Microbiol Lett ; 226(2): 347-53, 2003 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-14553932

RESUMO

Cell surface expression of protein has been widely used to display enzymes and antigens. Here we show that Pseudomonas syringae ice nucleation protein with a deletion of internal repeating domain (INC) can be used in Escherichia coli to display peptide in a conformationally active form on the outside of the folded protein by fusing to the C-terminus of INC. Diagnostic potential of this technology was demonstrated by effective mapping of antigenic epitopes derived from hepatitis C virus (HCV) core protein. Amino acids 1-38 and 26-53 of HCV core protein were found to react more sensitively in a native conformation with the HCV patient sera than commercial diagnostic antigen, c22p (amino acids 10-53) by display-ELISA. These results demonstrate that the bacterial cell surface display using INC is useful for peptide presentation and thus epitope mapping of antigen.


Assuntos
Mapeamento de Epitopos/métodos , Hepacivirus/imunologia , Antígenos da Hepatite C/imunologia , Proteínas do Core Viral/imunologia , Antígenos de Superfície/biossíntese , Antígenos de Superfície/genética , Antígenos de Superfície/imunologia , Proteínas da Membrana Bacteriana Externa/biossíntese , Proteínas da Membrana Bacteriana Externa/genética , Proteínas de Bactérias/genética , Clonagem Molecular , Ensaio de Imunoadsorção Enzimática/métodos , Escherichia coli/genética , Escherichia coli/metabolismo , Citometria de Fluxo , Genes Bacterianos , Genes Virais , Hepatite C/diagnóstico , Hepatite C/imunologia , Anticorpos Anti-Hepatite C/sangue , Anticorpos Anti-Hepatite C/imunologia , Antígenos da Hepatite C/química , Antígenos da Hepatite C/genética , Humanos , Microscopia de Fluorescência , Pseudomonas syringae/genética , Proteínas Recombinantes de Fusão/biossíntese , Proteínas Recombinantes de Fusão/imunologia , Transformação Bacteriana/genética , Proteínas do Core Viral/química , Proteínas do Core Viral/genética
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