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1.
Zhongguo Zhong Yao Za Zhi ; 44(23): 5191-5197, 2019 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-32237357

RESUMO

This study aims to investigate the PPARγ agonists isolated from the aqueous extract of Siegesbeckia pubescens( SPA) and their anti-inflammatory activities in vitro. The 293 T cells transfected transiently with PPARγ recombinant plasmid were used as a screening model to guide the isolation of PPARγ activitating components,and then PPARγ activities were measured by double luciferase reporter gene assay. The chemical structures were identified by chromatography or spectroscopic techniques. Furthermore,a UC inflammatory model in vitro was established on HT-29 cells by stimulating with TNF-α. The mRNA levels and secretion of proinflammatory cytokines on HT-29 cells,such as IL-1ß,TNF-α,IL-8,were detected by RT-PCR and ELISA. The results showed that five diterpenoids were obtained from the fraction D_(50) with the strongest PPARγ activity among others in SPA,and determined as kirenol( 1),darutigenol( 2),enantiomeric-2-ketone-15,16,19-three hydroxypinomane-8( 14)-ene-19-O-ß-D-glucoside( 3),darutoside( 4),enantiomeric-2-ß,15,16,19-four hydroxypinomane-8( 14)-ene-19-O-ß-D-glucoside( 5),respectively. All the compounds exhibited active effects on PPARγ in a concentration-dependent manner( P<0. 01). In addition,compound 1 significantly inhibited the expression of IL-1ß mRNA and secretion of IL-8 on HT-29 cells inflammation model( P<0. 001); both compounds 2 and 3 effectively inhibited the expression of IL-1ß,TNF-α,IL-8 mRNA and secretion of IL-8( P<0. 01 or P<0. 001),although at different extent; compound 4 significantly inhibited the expression of IL-1ß and TNF-α mRNA( P<0. 01 or P<0. 001),while compound 5 inhibited the expression of IL-1ß mRNA obviously( P<0. 001). In conclusion,the diterpenoids 1-5 isolated from S. pubescens have the PPARγ activation activities and potential effects of anti-UC in vitro.


Assuntos
Anti-Inflamatórios/farmacologia , Asteraceae/química , Diterpenos/farmacologia , PPAR gama/agonistas , Colite Ulcerativa , Citocinas/imunologia , Células HT29 , Humanos , Fator de Necrose Tumoral alfa
2.
Sheng Li Xue Bao ; 70(4): 361-368, 2018 Aug 25.
Artigo em Chinês | MEDLINE | ID: mdl-30112561

RESUMO

The aim of this study was to screen the genes related to the pathogenesis of major depression disorder (MDD) by bioinformatics. Taking GSE98793 chip data from GEO public database of National Biotechnology Information Center (NCBI) website as the research object, 116 differentially expressed genes (DEGs) were screened by R language limma package. Among the 116 DEGs, 66 genes were up-regulated and 50 down-regulated. The results of gene functional annotation analysis of Gene Ontology (GO) showed that the DEGs were mainly distributed in mitochondria intima and mitochondria. They were involved in copper ion binding, cysteine-type endopeptidase activity, the cell response of interleukin-1, protein processing and other biological processes. KEGG pathway enrichment analysis results showed that the DEGs were mainly concentrated in oxidative phosphorylation, Parkinson's disease, non-alcoholic fatty liver disease, Alzheimer's disease and Huntington's disease etc. The results of protein interaction network analysis showed that there were interactions among proteins encoded by 54 DEGs. Combined with the analysis results of the above methods, 11 key genes were screened out, including UQCRC1, GZMB, NDUFB9, NSF, SLC17A5, CTSH, NDUFB10, UQCR10, ATOX1, CST7 and CTSW, which could be used as candidate genes for the diagnosis and treatment of MDD. Taken together, the key genes were obtained by analyzing the microarray and the DEGs of MDD in the present study, which would provide important clues for revealing the molecular mechanism and clinical targeted therapy of depression.


Assuntos
Biologia Computacional , Transtorno Depressivo Maior/genética , Mapas de Interação de Proteínas , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Redes Reguladoras de Genes , Humanos , Análise de Sequência com Séries de Oligonucleotídeos
3.
Sci Rep ; 8(1): 3396, 2018 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-29467508

RESUMO

Light-flavour Baijiu is a type of Chinese liquor with a pure and mild flavour produced by traditional spontaneous solid-state fermentation. The flavour of this liquor has been found to vary in the different periods of annual production. To explore the factors affecting flavour, the microbiota of the surrounding environment, starter and fermentation process in different periods were investigated. Results showed that the ester content and acidity of light-flavour Baijiu were significantly lower when annual production was resumed after a summer break. HCA plot of volatile flavour profile and bacterial PCoA results indicated that the differences occurred at later stages, mainly due to different structures of Lactobacillus. Correlation analysis by O2PLS indicated that Lactobacillus positively correlated with esters. Species-level analysis showed that the lack of L. acetotolerans on the surface of the jar might cause a lag in fermentation and lower ester content. Thereafter, L. acetotolerans was revived during fermentation and enriched on the surface of the jar, which promoted ester formation. As important sources of L. acetotolerans, the air and fermentation jars played a critical role during fermentation. Therefore, this systematic study on environmental microbial ecology is valuable for quality control and to explore environmental microbiota functions during spontaneous fermentation.


Assuntos
Bebidas Alcoólicas/microbiologia , Fermentação/fisiologia , Aromatizantes/metabolismo , Microbiota/fisiologia , Microbiologia de Alimentos/métodos , Lactobacillus/fisiologia , Paladar/fisiologia , Compostos Orgânicos Voláteis/metabolismo
4.
Cancer Lett ; 420: 195-207, 2018 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-29425683

RESUMO

Uncontrolled excessive activation of Hedgehog (Hh) signaling pathway is linked to a number of human malignant tumorigenesis. To obtain valuable Hh pathway inhibitors from natural product, in present study, a pair of novel epimers, Cynanbungeigenin C (CBC) and D (CBD) from the plant Cynanchum bungei Decne were chemically characterized by multiple spectroscopic data and chemical derivatization, and evaluated for their inhibition on Hh pathway. Mechanistically, CBC and CBD block Hh pathway signaling not through targeting Smo and Sufu, but at the level of Gli. In addition, both eipmers significantly suppress Hh pathway-dependent Ptch+/-; p53-/- medulloblastoma in vitro and in vivo. Furthermore, both CBC and CBD inhibited two Smo mutants induced Hh pathway activation, which suggested that they are potential compounds for the treatment of medulloblastoma with primary or acquired resistance to current Smo inhibitors. These results highlight the potential of CBC and CBD as effective lead compounds in the treatment of medulloblastoma and other Hh-dependent malignancy.


Assuntos
Neoplasias Cerebelares/tratamento farmacológico , Cynanchum/química , Meduloblastoma/tratamento farmacológico , Fitosteróis/administração & dosagem , Fitosteróis/isolamento & purificação , Transdução de Sinais/efeitos dos fármacos , Animais , Neoplasias Cerebelares/metabolismo , Células HEK293 , Proteínas Hedgehog/metabolismo , Humanos , Meduloblastoma/metabolismo , Camundongos , Células NIH 3T3 , Fitosteróis/química , Fitosteróis/farmacologia , Extratos Vegetais/análise , Ensaios Antitumorais Modelo de Xenoenxerto , Proteína GLI1 em Dedos de Zinco/metabolismo
5.
Microbiol Res ; 206: 159-167, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29146252

RESUMO

Pseudomonas fluorescens 2P24 produces 2,4-diacetylphloroglucinol (2,4-DAPG) as the major antibiotic compound that protects plants from soil-borne diseases. Expression of the 2,4-DAPG biosynthesis enzymes, which are encoded by the phlACBD locus, is under the control of a delicate regulatory network. In this study, we identified a novel role for the outer membrane protein gene oprF, in negatively regulating the 2,4-DAPG production by using random mini-Tn5 mutagentsis. A sigma factor gene sigX was located immediately upstream of the oprF gene and shown to be a positive regulator for oprF transcription and 2,4-DAPG production. Genetic analysis of an oprF and sigX double-mutant indicated that the 2,4-DAPG regulation by oprF was dependent on SigX. The sigX gene did not affect PhlA and PhlD expression, but positively regulated the level of malonyl-CoA, the substrate of 2,4-DAPG synthesis, by influencing the expression of acetyl-CoA carboxylases. Further investigations revealed that sigX transcription was induced under conditions of salt starvation or glycine addition. All these findings indicate that SigX is a novel regulator of substrate supplements for 2,4-DAPG production.


Assuntos
Antibacterianos/metabolismo , Proteínas de Bactérias/genética , Regulação Bacteriana da Expressão Gênica/genética , Proteínas de Membrana/genética , Pseudomonas fluorescens/genética , Pseudomonas fluorescens/metabolismo , Fator sigma/genética , Acetil-CoA Carboxilase/metabolismo , Proteínas de Bactérias/metabolismo , Sequência de Bases , Mapeamento Cromossômico , DNA Bacteriano , Escherichia coli/genética , Perfilação da Expressão Gênica , Genes Bacterianos/genética , Vetores Genéticos , Proteínas de Membrana/metabolismo , Mutação , Fenótipo , Floroglucinol/análogos & derivados , Floroglucinol/metabolismo , Biossíntese de Proteínas , Pseudomonas fluorescens/crescimento & desenvolvimento , Rhizoctonia , Fator sigma/metabolismo , Transcrição Genética , Ativação Transcricional
6.
Front Aging Neurosci ; 9: 145, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28567013

RESUMO

Background: Apolipoprotein E (APOE) ε4 is the only established risk gene for late-onset, sporadic Alzheimer's disease (AD). Previous studies have provided inconsistent evidence for the effect of APOE ε4 status on the visuospatial working memory (VSWM). Objective: The aim was to investigate the effect of APOE ε4 on VSWM with an event-related potential (ERP) study in healthy controls (HC) and amnestic mild cognitive impairment (aMCI) patients. Methods: The study recorded 39 aMCI patients (27 APOE ε4 non-carriers and 12 APOE ε4 carriers) and their 43 matched controls (25 APOE ε4 non-carriers and 18 APOE ε4 carriers) with an 64-channel electroencephalogram. Participants performed an N-back task, a VSWM paradigm that manipulated the number of items to be stored in memory. Results: The present study detected reduced accuracy and delayed mean correct response time (RT) in aMCI patients compared to HC. P300, a positive component that peaks between 300 and 500 ms, was elicited by the VSWM task. In addition, aMCI patients showed decreased P300 amplitude at the central-parietal (CP1, CPz, and CP2) and parietal (P1, Pz, and P2) electrodes in 0- and 1-back task compared to HC. In both HC and aMCI patients, APOE ε4 carriers showed reduced P300 amplitude with respect to non-carriers, whereas no significant differences in accuracy or RT were detected between APOE ε4 carriers and non-carriers. Additionally, standardized low-resolution brain electromagnetic tomography analysis (s-LORETA) showed enhanced brain activation in the right parahippocampal gyrus (PHG) during P300 time range in APOE ε4 carriers with respect to non-carriers in aMCI patients. Conclusion: It demonstrated that P300 amplitude could predict VSWM deficits in aMCI patients and contribute to early detection of VSWM deficits in APOE ε4 carriers.

7.
J Food Prot ; 80(3): 431-442, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28207306

RESUMO

Standards and regulations related to spirit drinks have been established by different countries and international organizations to ensure the safety and quality of spirits. Here, we introduce the principles of food safety and quality standards for alcoholic beverages and then compare the key indicators used in the distinct standards of the Codex Alimentarius Commission, the European Union, the People's Republic of China, the United States, Canada, and Australia. We also discuss in detail the "maximum level" of the following main contaminants of spirit drinks: methanol, higher alcohols, ethyl carbamate, hydrocyanic acid, heavy metals, mycotoxins, phthalates, and aldehydes. Furthermore, the control measures used for potential hazards are introduced. Harmonization of the current requirements based on comprehensive scope analysis and the risk assessment approach will enhance both the trade and quality of distilled spirits. This review article provides valuable information that will enable producers, traders, governments, and researchers to increase their knowledge of spirit drink safety requirements, control measures, and research trends.


Assuntos
Bebidas/normas , Inocuidade dos Alimentos , Austrália , Canadá , China , Humanos , Internacionalidade , Estados Unidos
8.
Zhonghua Nan Ke Xue ; 23(7): 615-619, 2017 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-29723454

RESUMO

Objective: To investigate the clinical effects of aripiprazole on sexual dysfunction induced by amisulpride or risperidone in male patients with schizophrenia. METHODS: This study included 75 male patients with drug-induced secondary sexual dysfunction after treated with amisulpride or risperidone for first-episode schizophrenia between October 2014 and October 2016. We substituted aripiprazole for amisulpride or risperidone, gradually increased the dose from 10 to 30 mg/d within 2 weeks, and maintained 30 mg/d from the 3rd week. At 4 and 8 weeks after medication, we evaluated the sexual function of the patients, measured the levels of serum prolactin (PRL) and testosterone (T), obtained the scores of the Positive and Negative Symptoms Scale (PANSS), recorded adverse reactions, and compared the parameters with those before aripiprazole administration. RESULTS: Compared with pre-aripiprazole administration, the patients showed significant increases after 4 weeks of medication in the sexual function score (24.3 ± 2.1 vs 32.6 ± 3.6, P <0.05) and T level (ï¼»13.3 ± 2.7ï¼½ vs ï¼»17.4±3.0ï¼½ mmol/L, P <0.05) but a decreased level of PRL (ï¼»38.5 ± 10.5ï¼½ vs ï¼»27.9 ± 8.2ï¼½ ng/ml, P <0.05). At 8 weeks, the sexual function score and serum PRL were both restored to the baseline levels at admission, and the erectile function score, ejaculation score, total score, and serum T level even exceeded the baseline, though with no statistically significant differences (P >0.05). In comparison with pre-aripiprazole administration, the PANSS score was significantly decreased at 4 weeks after medication (62.1 ± 4.9 vs 57.2 ± 5.5, P <0.05) and even lower at 8 weeks (51.2 ± 5.2) (P <0.05). The incidence rates of medication-related excitation, dizziness, insomnia, and loss of appetite were 6.7%, 5.3%, 4.0% and 1.3% respectively, and no other serious adverse reactions were observed. CONCLUSIONS: Aripiprazole is effective for the treatment of drug-induced sexual dysfunction in schizophrenic men by continuously alleviating their positive and negative symptoms and meanwhile improving their sexual function and restoring their sexual hormone levels.


Assuntos
Antipsicóticos/administração & dosagem , Antipsicóticos/efeitos adversos , Aripiprazol/administração & dosagem , Risperidona/efeitos adversos , Esquizofrenia/tratamento farmacológico , Disfunções Sexuais Fisiológicas/induzido quimicamente , Disfunções Sexuais Fisiológicas/tratamento farmacológico , Sulpirida/análogos & derivados , Amissulprida , Esquema de Medicação , Humanos , Masculino , Prolactina/sangue , Esquizofrenia/sangue , Comportamento Sexual , Disfunções Sexuais Fisiológicas/sangue , Sulpirida/efeitos adversos , Testosterona/sangue , Resultado do Tratamento
9.
Nat Prod Commun ; 11(6): 747-8, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27534107

RESUMO

Two new 13, 14/14, 15-disecopregnane-type skeleton C21 steroidal aglycones, neocynapanogenin G (1) and neocynapanogenin H (2), were isolated from the hydrolyzed extract of the CHCl3 soluble extract of the roots of Cynanchun paniculatum. Their structures were determined on the basis of chemical evidence and extensive spectroscopic methods, including 1D and 2D NMR spectroscopy. Compound 1 displayed signifidant inhibition of the Hedgehog signaling pathway in vitro.


Assuntos
Cynanchum/química , Medicamentos de Ervas Chinesas/química , Iridoides/química , Raízes de Plantas/química , Esteroides/química , Animais , Linhagem Celular , Ouriços-Cacheiros/genética , Ouriços-Cacheiros/metabolismo , Humanos , Estrutura Molecular , Transdução de Sinais/efeitos dos fármacos
10.
Eur J Pharmacol ; 789: 370-384, 2016 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-27448502

RESUMO

Stephanthraniline A (STA), a C21 steroid isolated from Stephanotis mucronata (Blanco) Merr., was previously shown to inhibit T cells activation and proliferation in vitro and in vivo. The purpose of this study was to further evaluate the in vivo immunosuppressive activity of STA and to elucidate its potential mechanisms. The results showed that pretreatment with STA significantly attenuated concanavalin A (Con A)-induced hepatitis and reduced CD4(+) T cells activation and aggregation in hepatic tissue in mice. STA directly suppressed the activation and proliferation of Con A-induced CD4(+) T cells, and inhibited NFAT, NFκB and MAPK signaling cascades in activated CD4(+) T cells in vitro. Moreover, it was proved that STA inhibited T cells activation and proliferation through proximal T cell-receptor (TCR) signaling- and Ca(2+) signaling-independent way. The molecular docking studies predicted that STA could tight bind to PKCθ via five hydrogen. The further findings indicated STA directly inhibited PKCθ kinase activity, and its phosphorylation in activated CD4(+) T cells in vitro. Collectively, the present study indicated that STA could protect against CD4(+) T cell-mediated immunological hepatitis in mice through PKCθ and its downstream NFAT, NFκB and MAPK signaling cascades. These results highlight the potential of STA as an effective leading compound for use in the treatment of CD4(+) T cell-mediated inflammatory and autoimmune diseases.


Assuntos
Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/imunologia , Diterpenos/farmacologia , Hepatite/tratamento farmacológico , Hepatite/imunologia , Isoenzimas/antagonistas & inibidores , Ativação Linfocitária/efeitos dos fármacos , Proteína Quinase C/antagonistas & inibidores , Animais , Sinalização do Cálcio/efeitos dos fármacos , Domínio Catalítico , Agregação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Diterpenos/metabolismo , Diterpenos/uso terapêutico , Feminino , Hepatite/metabolismo , Hepatite/patologia , Isoenzimas/química , Isoenzimas/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Camundongos , Simulação de Acoplamento Molecular , NF-kappa B/metabolismo , Fatores de Transcrição NFATC/metabolismo , Fosforilação/efeitos dos fármacos , Proteína Quinase C/química , Proteína Quinase C/metabolismo , Proteína Quinase C-theta , Proteínas Quinases/metabolismo
11.
Nutrients ; 8(5)2016 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-27136583

RESUMO

Long-term use of fish oil (FO) is known to induce oxidative stress and increase the risk of Alzheimer's disease in humans. In the present study, peanut skin extract (PSE), which has strong antioxidant capacity, was mixed with FO to reduce its side effects while maintaining its beneficial properties. Twelve-week Institute of Cancer Research (ICR) mice were used to conduct animal behavior tests in order to evaluate the memory-enhancing ability of the mixture of peanut skin extract and fish oil (MPF). MPF significantly increased alternations in the Y-maze and cognitive index in the novel object recognition test. MPF also improved performance in the water maze test. We further sought to understand the mechanisms underlying these effects. A significant decrease in superoxide dismutase (SOD) activity and an increase in malonyldialdehyde (MDA) in plasma were observed in the FO group. The MPF group showed reduced MDA level and increased SOD activity in the plasma, cortex and hippocampus. Furthermore, the gene expression levels of brain-derived neurotrophic factor (BDNF) and cAMP responsive element-binding protein (CREB) in the hippocampus were increased in the MPF group, while phosphorylation of protein kinase B (AKT), extracellular signal-regulated kinase (ERK) and CREB in the hippocampus were enhanced. MPF improves memory in mice via modulation of anti-oxidative stress and activation of BDNF/ERK/CREB signaling pathways.


Assuntos
Arachis/química , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Óleos de Peixe/farmacologia , Extratos Vegetais/farmacologia , Animais , Antioxidantes , Fator Neurotrófico Derivado do Encéfalo/genética , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , MAP Quinases Reguladas por Sinal Extracelular/genética , Óleos de Peixe/administração & dosagem , Óleos de Peixe/química , Regulação da Expressão Gênica/efeitos dos fármacos , Camundongos , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/administração & dosagem , Extratos Vegetais/química
12.
Nat Prod Commun ; 11(12): 1797-1800, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30508336

RESUMO

Two new 8, 14-seco skeleton C(21) steroidal aglycones, cynanbungeigenin A (1) and cynanbungeigenin B (2), were isolated from the hydrolyzed extract of the EtOAc soluble extract of the roots of Cynanchum bungei. Their structures were determined on the basis of chemical evidence and extensive spectroscopic methods, including 1D and 2D NMR spectroscopy.


Assuntos
Cynanchum/química , Pregnanos/isolamento & purificação , Animais , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Proteínas Hedgehog/antagonistas & inibidores , Camundongos , Células NIH 3T3 , Extratos Vegetais/química , Raízes de Plantas/química , Pregnanos/química , Pregnanos/farmacologia , Espectroscopia de Prótons por Ressonância Magnética
13.
Eur J Med Chem ; 75: 301-7, 2014 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-24556145

RESUMO

Our previous study reported that a mixture of cerebrosides from traditional Chinese medicine Baifuzi could activate BKCa channel. It is curious to know the effect of each single cerebroside on the channel. Here we isolated 5 pure cerebrosides from the mixture and determined their chemical structures. The most potent one increased the single channel open probability 6 folds with EC50 value of 1.0 µM. The structure-activity relationship revealed that acyl chain length of cerebrosides has potent effect, while configuration of double bond at C8-C9 on their long chain base has weak effect on the channel activity. Thus, this research provides a guide for design and synthesis of a lead cerebroside with more potent effect on the BKCa channel.


Assuntos
Cerebrosídeos/química , Cerebrosídeos/farmacologia , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/farmacologia , Canais de Potássio Ativados por Cálcio de Condutância Alta/agonistas , Canais de Potássio Ativados por Cálcio de Condutância Alta/metabolismo , Animais , Células CHO , Cerebrosídeos/isolamento & purificação , Cricetulus , Canais de Potássio Ativados por Cálcio de Condutância Alta/química , Técnicas de Patch-Clamp , Estrutura Terciária de Proteína/efeitos dos fármacos , Relação Estrutura-Atividade
14.
Guang Pu Xue Yu Guang Pu Fen Xi ; 29(8): 2152-6, 2009 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-19839328

RESUMO

High temperature coal tar was used as raw materials, and was distilled to 280 degrees C for getting coal tar soft pitch. Then refined soft pitch was obtained by solvent extracting and subsequent settlement method. Its soft point was 32 degrees C; the group compositions consisted of 53.67% heptane soluble, 39.47% heptane insoluble but toluene soluble, 6.86% toluene insoluble and 0.06% quinoline insoluble. The relative average molecular weight was about 292. Its average molecular formula was C22.22 H16.32 N0.12 S0.06 O0.33; the total content of heteroatom was less than 1. IR analytic results showed that its heteroatom O existed in the R-O-R and Ar-O-R structure; its heteroatom N existed in the R-NH-R and -N=, with the latter being primary. Its average structure was obtained by improved Brown-Lander model: five-membered condensed rings. UV analysis indicated that the majority was linear arrangement, and the minority was surface arrangement; namely, the chemical structure of the samples was mainly the cata-condensed structure, while the minority was peri-condensation.

15.
Guang Pu Xue Yu Guang Pu Fen Xi ; 29(4): 1032-5, 2009 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-19626897

RESUMO

We developed a method to screen paralytic shellfish poisoning (PSP) toxins based on their functional activity. The assay was a fluorimetric assay by detecting changes in the membrane potential of transitional cell carcinoma of the bladder cells T24 and involved several steps: stain of T24 cells with fluorescent dye bis-oxonol, cell depolarization with veratridine, and inhibition of depolarization with PSP toxins GTX2, 3 or shellfish samples containing PSP toxins. Toxic potency of the samples was evaluated by measuring toxin-induced changes in membrane potential. Within 2-100 nmol x L(-1) of GTX2, 3, veratridine-induced depolarization was shown to be inhibited by GTX2, 3 in a dose-dependent manner. There was a linear correlation between the percentage of inhibition and toxin concentration. The PSP toxin value in shellfish obtained by this fluorescence assay was in concordance with that by the mouse bioassay, and with higher sensitivity. In conclusion, the fluorescent dye method based on changes in membrane potential was a rapid, specific, and reliable method for detecting paralytic shellfish poisoning toxins in shellfish.


Assuntos
Toxinas Marinhas/análise , Potenciais da Membrana/efeitos dos fármacos , Intoxicação por Frutos do Mar/fisiopatologia , Frutos do Mar/análise , Espectrometria de Fluorescência/métodos , Animais , Linhagem Celular Tumoral , Membrana Celular/química , Humanos , Masculino , Toxinas Marinhas/toxicidade , Camundongos , Camundongos Endogâmicos BALB C , Moluscos/química , Frutos do Mar/toxicidade , Intoxicação por Frutos do Mar/diagnóstico
16.
J Microbiol Biotechnol ; 18(4): 711-7, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18467865

RESUMO

To speed up the conversion of rice straw into feeds in a low-temperature region, a start culture used for ensiling rice straw at low temperature was selected by continuous enrichment cultivation. During the selection, the microbial source for enrichment was rice straw and soil from two places in Northeast China. Lab-scale rice straw fermentation at 10 degrees C verified, compared with the commercial inocculant, that the selected start culture lowered the pH of the fermented rice straw more rapidly and produced more lactic acid. The results from denatured gradient gel eletrophoresis showed that the selected start culture could colonize into the rice straw fermentation system. To analyze the composition of the culture, a 16S clone library was constructed. Sequencing results showed that the culture mainly consisted of two bacterial species. One (A) belonged to Lactobacillus and another (B) belonged to Leuconostoc. To make clear the roles of composition microbes in the fermented system, quantitative PCR was used. For species A, the DNA mass increased continuously until sixteen days of the fermentation, which occupied 65%. For species B, the DNA mass amounted to 5.5% at six days of the fermentation, which was the maximum relative value during the fermentation. To the authors' best knowledge, this is the first report on ensiling rice straw with a selected starter at low temperature and investigation of the fermented characteristics.


Assuntos
Lactobacillus/metabolismo , Leuconostoc/metabolismo , Oryza/metabolismo , Caules de Planta/metabolismo , Microbiologia do Solo , China , Temperatura Baixa , DNA Bacteriano/genética , DNA Bacteriano/metabolismo , DNA Ribossômico/genética , Fermentação , Concentração de Íons de Hidrogênio , Lactobacillus/classificação , Lactobacillus/genética , Lactobacillus/isolamento & purificação , Leuconostoc/classificação , Leuconostoc/genética , Leuconostoc/isolamento & purificação , Dados de Sequência Molecular , Filogenia , RNA Ribossômico 16S/genética
17.
J Environ Sci (China) ; 19(1): 67-73, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17913156

RESUMO

To confirm the optimum cultivation conditions for analyzing lactic acid bacterial communities and to provide the cultivation foundation for lactic acid bacterial communities that were used to convert straw into fodder, fermented rice straw was inoculated into 13 different broths. After 48 h of cultivation, pH values, volatile products, and microbial diversity were analyzed. Except for LAB broth, the pH values of the other broths could decrease to approximately 4.5. GC/MS analysis showed that lactic acid in Tomato MRS broth, MRS broth, LAB broth, and Tomato juice broth was higher than that in the other broths. DNA concentration analysis showed that the counts of microbes in Tomato MRS broth were 2.5 times of those in other broths and that tomato juice favored the reproduction of the microbes. Denaturing gradient gel electrophoresis (DGGE) analysis showed that the number of lactic acid bacterial species in HYA broth, Tomato juice broth, and Tomato MRS broth were higher than those in the other broths.


Assuntos
Oryza/microbiologia , Sequência de Bases , Meios de Cultura , Primers do DNA , DNA Bacteriano/análise , Eletroforese em Gel de Poliacrilamida , Cromatografia Gasosa-Espectrometria de Massas , Concentração de Íons de Hidrogênio , Especificidade da Espécie , Volatilização
18.
Huan Jing Ke Xue ; 28(6): 1392-6, 2007 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-17674756

RESUMO

Aimed to utilize rice straw and lessen the pressure of environment, the rice straw was used as the fermentation material, and a lactic acid bacteria community SFC-2 from my laboratory was inoculated into the rice straw to investigate the inoculation effects. After 30 days fermentation, the inoculated fermented straw smelt acid-fragrant, and the pH value was 3.8, which was lower than the control of 4.1. Furthermore, lactic acid concentration was more than that in the control. Especially L-lactic acid concentration was two times more than in the control, and the crude protein content was 10.16% higher than that in the control, and the crude fiber content was 3.2% lower than that in the control. From the patterns of denaturing gradient gel electrophoresis (DGGE), Lactobacillus plantarum, Lactobacillus fermentum and Lactobacillus paracasei rapidly became the advantageous species in the inoculated straws. However, Enterobacter sakazakii, Pantoea agglomerans, Enterobacter endosymbiont, Pantoea ananatis, whichwere predominate in the controls, were not detected in the inoculated straws, and the fermented quality was improved significantly.


Assuntos
Fermentação , Lactobacillus/metabolismo , Caules de Planta/microbiologia , Eliminação de Resíduos/métodos , Eletroforese em Gel de Poliacrilamida , Ácido Láctico/análise , Oryza/microbiologia
19.
Huan Jing Ke Xue ; 28(5): 1088-94, 2007 May.
Artigo em Chinês | MEDLINE | ID: mdl-17633184

RESUMO

To obtain the community that could accelerate the fermentation of the air-dried crop straws, a lactic acid bacteria community SFC-2 was constructed from the natural fermented products of the corn straw and rice straw by continuous restricted subcultivation in the MRS-S broth. The SFC-2 could lower the pH of the broth quickly, and produce high amount of lactic acid. The microbial composition of the SFC-2 became stable from the 25th generation according to the results of denaturing gradient gel electrophoresis (DGGE). The pH value of the SFC-2 dropped to 3.8 and the amount of lactic acid reached 10.64 mg x mL(-1) after 12 h cultivation in the broth, which contained 64% L-(+) lactic acid. Using morphological methods, four strains were isolated from the SFC-2 and they all belonged to Lactobacillus. The closest species were L. fermentum, L. plantarum, L. paracasei and L. paracasei sub sp., respectively. At the same time, the composition of the SFC-2 was also analyzed by constructing 16S rDNA clone library. The results of 16S rDNA sequencing showed that the closest species of seven clones were mainly L. fermentum, L. plantarum and L. paracasei. In clone libraries, 76.3% belonged to L. fermentum, 20.3% belonged to L. plantarum and 3.4% belonged to L. paracasei.


Assuntos
Biodiversidade , Ácido Láctico/metabolismo , Lactobacillus/crescimento & desenvolvimento , Caules de Planta/microbiologia , Fermentação , Lactobacillus/classificação , Lactobacillus/genética , Oryza/crescimento & desenvolvimento , Caules de Planta/química , RNA Ribossômico 16S/genética , Zea mays/crescimento & desenvolvimento
20.
Wei Sheng Wu Xue Bao ; 46(5): 767-72, 2006 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-17172026

RESUMO

Alfalfa is the most important forage grass that is difficult to ensile for good quality. Using silage inoculants are the important way for preservation of alfalfa silage. Through continuous restricted subcultivation, a lactic acid bacteria (LAB) community Al2 was selected from well-fermented alfalfa silage. Plate isolation and Denaturing Gradient Gel Electrophoresis (DGGE), construction of 16S rDNA clone library were used to identify the composition diversity of Al2 community, with 7 strains detected, and they were all belonged to Lactobacillus. The composition ratios of the 7 strains were 55.21%, 19.79%, 14.58%, 3.13%, 3.13%, 3.13%, 1.03% according to 16S rDNA clone library. Al2-1i, Al2-2i, Al2-3i, corresponding to L. plantarum (99.9%), L. kimchii (99.4%), L. farciminis (100%) were detected by plate isolation. Among 3 isolates, Al2-1i had the highest ability of dropping pH and producing lactic acid, and the amount of lactic acid was reach to 18g/L at 24h cultivated in MRS media. The ability of dropping pH and producing lactic acid of Al2-3i was the lowest. From DGGE profiles, the dominant strains in Al2 community were L. plantarum and L. kimchii. L. plantarum was detected during the whole process, and L. kimchii was detected in the later phase.


Assuntos
Lactobacillus/isolamento & purificação , Medicago sativa/microbiologia , Silagem/microbiologia , Eletroforese em Gel de Poliacrilamida , Fermentação , Lactobacillus/genética , Lactobacillus/metabolismo , RNA Ribossômico 16S/genética
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