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1.
J Sci Food Agric ; 99(12): 5516-5525, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31099894

RESUMO

BACKGROUND: Sensory perception is a dynamic process occurring sequentially. The dynamic analysis of the perception of sensory characteristics in meat is important to understand complex meat sensory characteristics. Temporal dominance of sensations (TDS) is a dynamic sensory method that captures the 'dominance of sensations' throughout food consumption, and it is possible to calculate the relative contribution of various sensory characteristics by 'dominance rate' over time. The objective of this study was to assess the major sensory characteristics of the dynamic sensory perception of pork loin. Using the TDS, we evaluated pork loins derived from pigs with different genetic and feeding backgrounds. Moreover, we checked the integrity of the TDS by comparing the TDS results with a descriptive sensory analysis and a physico-chemical analysis. RESULTS: Seven types of pork loin were evaluated by TDS, and 'tender and/or soft,' 'tough and/or hard,' 'juicy,' 'dry,' 'fat melting,' 'smoothness,' 'sourness,' 'umami,' and 'beast odors' became dominant in at least one type of pork loin. The dynamics of the perception of pork sensory characteristics was also depicted by TDS. In addition, TDS and descriptive analysis demonstrated similarity in principal component analysis. CONCLUSION: TDS demonstrated the major sensory characteristics on the dynamic sensory perception of pork loin. © 2019 Society of Chemical Industry.


Assuntos
Carne/análise , Paladar , Ração Animal/análise , Animais , Dureza , Carne/classificação , Suínos/metabolismo
2.
Genome Announc ; 6(25)2018 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-29930046

RESUMO

Lactobacillus plantarum LQ80 is a strain isolated from liquid feed for pigs. We determined the complete genome sequence of this strain using the PacBio RS II platform. LQ80 contained a single circular chromosome of 3,230,192 bp, with 44.66% G+C content and seven plasmids.

3.
Proc Inst Mech Eng H ; 231(9): 907-922, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28410565

RESUMO

Wedge-shaped defects are frequently observed on the cervical region of the human tooth. Previously, most studies explained that improper tooth-brushing causes such defects. However, recent clinical observation suggested that the repeated stress due to occlusal force may induce the formation of these wedge-shaped defects. In this study, therefore, two-dimensional human tooth models are considered with and without a wedge-shaped defect by applying the finite element method. To evaluate large stress concentrations accurately, a method of analysis is discussed in terms of the intensity of singular stress fields appearing at the tip of the sharp wedge-shaped defect. The effects of the position and direction of occlusion on the intensity of singular stress fields are discussed before and after restoration with composite resins.


Assuntos
Força de Mordida , Resinas Compostas , Restauração Dentária Permanente , Análise de Elementos Finitos , Dente Molar/fisiologia , Estresse Mecânico , Fenômenos Biomecânicos , Humanos
4.
Int J Syst Evol Microbiol ; 66(10): 3873-3877, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27380964

RESUMO

A Gram-stain-negative, rod-shaped, endospore-forming bacterium, strain LOOC204T, was isolated from corn silage that had been prepared and stored in Hokkaido, Japan. The isolate grew well at 4-37 °C and at pH 6.0-8.5. The major cellular fatty acids were anteiso-C15 : 0, C16 : 0, iso-C14 : 0 and iso-C16 : 0. The major menaquinone was MK-7. Diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, three unidentified aminophospholipids, one unidentified phospholipid, two unidentified aminolipids and three unidentified lipids were detected as the cellular polar lipids. The genomic DNA G+C content of LOOC204T was 52.2±0.7 mol%. A comparative 16S rRNA gene sequence analysis showed that LOOC204T represented a member of the genus Paenibacillus, and high levels of sequence similarity of LOOC204T with Paenibacillus borealis KK19T (97.5 %) and Paenibacillusjilunlii Be17T (97.4 %) were found. Based on sequence analysis of the RNA polymerase ß subunit (rpoB) gene, LOOC204T was clearly separated from its phylogenetic neighbors in the genus Paenibacillus. DNA-DNA hybridisation experiments showed that LOOC204T displayed less than 40 % reassociation values toward its nearest phylogenetic neighbours of the genus Paenibacillus, indicating the unique taxonomic status of LOOC204T. Based on these data, we conclude that strain LOOC204T represents a novel species of the genus Paenibacillus, named Paenibacillus silageisp. nov. The type strain is LOOC204T (=JCM 30974T=DSM 101953T).


Assuntos
Paenibacillus/classificação , Filogenia , Silagem/microbiologia , Zea mays/microbiologia , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , RNA Polimerases Dirigidas por DNA/genética , Ácidos Graxos/química , Japão , Hibridização de Ácido Nucleico , Paenibacillus/genética , Paenibacillus/isolamento & purificação , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
5.
Immunogenetics ; 68(9): 693-701, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27236661

RESUMO

The nucleotide-binding domain, leucine-rich-containing family, pyrin-domain containing-3 (NLRP3) inflammasome comprises the major components caspase-1, apoptosis-associated speck-like protein containing a caspase recruitment domain (ASC), and NLRP3. NLRP3 plays important roles in maintaining immune homeostasis mediated by intestinal microorganisms and in the immunostimulatory properties of vaccine adjuvants used to induce an immune response. In the present study, we first cloned a complementary DNA (cDNA) encoding porcine ASC because its genomic sequence was not completely determined. The availability of the ASC cDNA enabled us to reconstitute porcine NLRP3 inflammasomes using an in vitro system that led to the identification of the immune functions of porcine NLRP3 and ASC based on the production of interleukin-1ß (IL-1ß). Further, we identified six synonymous and six nonsynonymous single-nucleotide polymorphisms (SNPs) in the coding sequence of NLRP3 of six breeds of pigs, including major commercial breeds. Among the nonsynonymous SNPs, the Q969R polymorphism is associated with an increased release of IL-1ß compared with other porcine NLRP3 variants, indicating that this polymorphism represents a gain-of-function mutation. This allele was detected in 100 % of the analyzed Chinese Jinhua and Japanese wild boars, suggesting that the allele is maintained in the major commercial native European breeds Landrace, Large White, and Berkshire. These findings represent an important contribution to our knowledge of the diversity of NLRP3 nucleotide sequences among various pig populations. Moreover, efforts to exploit the gain of function induced by the Q969R polymorphism promise to improve pig breeding and husbandry by conferring enhanced resistance to pathogens as well as contributing to vaccine efficacy.


Assuntos
Povo Asiático/genética , Inflamassomos/genética , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Polimorfismo de Nucleotídeo Único/genética , População Branca/genética , Animais , Apoptose , Clonagem Molecular , Células HEK293 , Humanos , Suínos
6.
Int J Syst Evol Microbiol ; 65(Pt 6): 1981-1985, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25807979

RESUMO

Using a polyphasic taxonomic approach, we investigated three bacterial strains - IWT30T, IWT8 and IWT75 - isolated from total mixed ration silage prepared in Hachimantai, Iwate, Japan. The isolates comprised Gram-stain positive, non-motile, non-spore-forming, catalase-negative, rod-shaped bacteria. Good growth occurred at 15-45 °C and at pH 4.0-7.5. Their major cellular fatty acids were C18:1ω9c and C19:1 cyclo 9,10.The G+C content of genomic DNA of strain IWT30T was 44.6 mol%. Comparative 16S rRNA gene sequence analysis showed that these novel strains belonged to the genus Lactobacillus. These strains shared 100 % 16S rRNA gene sequence similarity and were most closely related to the type strains of Lactobacillus silagei, Lactobacillus odoratitofui, Lactobacillus similis, Lactobacillus collinoides, Lactobacillus paracollinoides and Lactobacillus kimchicus, with sequence similarity values of 99.5, 98.8, 98.7, 97.8, 97.8 and 96.8 %, respectively. The level of DNA-DNA relatedness between these strains and their closest phylogenetic neighbours was less than 30 %. On the basis of additional phylogenetic analysis of pheS and rpoA gene sequences and phenotypic and chemotaxonomic characteristics, we conclude that these three strains represent a novel species of the genus Lactobacillus, for which we propose the name Lactobacillus mixtipabuli sp. nov. The type strain is IWT30T ( = JCM 19805T = DSM 28580T).


Assuntos
Lactobacillus/classificação , Filogenia , Silagem/microbiologia , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Fermentação , Genes Bacterianos , Japão , Lactobacillus/genética , Lactobacillus/isolamento & purificação , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
7.
Int J Syst Evol Microbiol ; 64(Pt 4): 1229-1236, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24421273

RESUMO

A gram-stain-positive, facultatively anaerobic, non-spore-forming, catalase-negative, coccoid-shaped bacterial strain, designated BV2(T), was isolated from the vaginal mucosa of a beef cow in Japan. Phylogenetic analysis showed that the isolate shared high 16S rRNA gene sequence similarity (92.9 %) with Aerococcus suis 1821/02(T) and low similarity (<92.7 %) with any other recognized species of the genus Aerococcus. The DNA G+C content was 44.7 mol%, which is within the range observed among species of the genus Aerococcus (37.5-48.4 mol%). The major cellular fatty acid was C18 : 1ω9c, similar to other type strains of species of the genus Aerococcus. The results of genotypic, phenotypic and chemotaxonomic analyses as well as the low degree of DNA-DNA relatedness with all recognized members of the genus Aerococcus indicate that strain BV2(T) represents a novel species of the genus Aerococcus, for which the name Aerococcus vaginalis sp. nov. is proposed. The type strain is BV2(T) ( = JCM 19163(T) = DSM 27293(T)). Emended descriptions of Aerococcus suis, Aerococcus viridans, Aerococcus urinaeequi, Aerococcus urinaehominis, Aerococcus urinae, Aerococcus christensenii and Aerococcus sanguinicola are also presented.


Assuntos
Aerococcus/classificação , Bovinos/microbiologia , Filogenia , Vagina/microbiologia , Aerococcus/genética , Aerococcus/isolamento & purificação , Animais , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Feminino , Japão , Dados de Sequência Molecular , Mucosa/microbiologia , Hibridização de Ácido Nucleico , RNA Ribossômico 16S/genética
8.
Anim Sci J ; 85(1): 25-31, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23638678

RESUMO

Effect of the methane inhibitor, bromochloromethane (BCM) and dietary substrate, fumarate, on microbial community structure of acetogen bacteria in the bovine rumen was investigated through analysis of the formyltetrahydrofolate synthetase gene (fhs). The fhs sequences obtained from BCM-untreated, BCM-treated, fumarate-untreated and fumarate-treated bovine rumen were categorized into homoacetogens and nonhomoacetogenic bacteria by homoacetogen similarity scores. Phylogenetic tree analysis indicated that most of the fhs sequences categorized into homoacetogens were divided into nine clusters, which were in close agreement with a result shown in a self-organizing map. The diversity of the fhs sequences from the BCM-treated rumen was significantly different from those from BCM-non-treated rumen. Principal component analysis also showed that addition of BCM to the rumen altered the population structure of acetogenic bacteria significantly but the effect of fumarate was comparatively minor. These results indicate that BCM affects diversity of actogens in the bovine rumen, and changes in acetogenic community structure in response to methane inhibitors may be caused by different mechanisms.


Assuntos
Acetobacterium/efeitos dos fármacos , Acetobacterium/enzimologia , Carga Bacteriana/efeitos dos fármacos , Bovinos/microbiologia , Formiato-Tetra-Hidrofolato Ligase/genética , Fumaratos/farmacologia , Variação Genética/efeitos dos fármacos , Variação Genética/genética , Hidrocarbonetos Halogenados/farmacologia , Filogenia , Rúmen/microbiologia , Animais
9.
Proc Inst Mech Eng H ; 227(12): 1312-8, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24077258

RESUMO

This study focused on the application of novel finite-element analysis software for constructing a finite-element model from the computed tomography data of a human dentulous mandible. The finite-element model is necessary for evaluating the mechanical response of the alveolar part of the mandible, resulting from occlusal force applied to the teeth during biting. Commercially available patient-specific general computed tomography-based finite-element analysis software was solely applied to the finite-element analysis for the extraction of computed tomography data. The mandibular bone with teeth was extracted from the original images. Both the enamel and the dentin were extracted after image processing, and the periodontal ligament was created from the segmented dentin. The constructed finite-element model was reasonably accurate using a total of 234,644 nodes and 1,268,784 tetrahedral and 40,665 shell elements. The elastic moduli of the heterogeneous mandibular bone were determined from the bone density data of the computed tomography images. The results suggested that the software applied in this study is both useful and powerful for creating a more accurate three-dimensional finite-element model of a dentulous mandible from the computed tomography data without the need for any other software.


Assuntos
Análise do Estresse Dentário/métodos , Dentição , Análise de Elementos Finitos , Mandíbula/fisiologia , Modelos Biológicos , Radiografia Dentária/métodos , Tomografia Computadorizada por Raios X/métodos , Adulto , Simulação por Computador , Módulo de Elasticidade/fisiologia , Humanos , Imageamento Tridimensional/métodos , Masculino , Mandíbula/anatomia & histologia , Interpretação de Imagem Radiográfica Assistida por Computador/métodos
10.
Int J Syst Evol Microbiol ; 63(Pt 12): 4613-4618, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23919960

RESUMO

A Gram-reaction-positive, facultatively anaerobic, non-spore-forming and catalase-negative rod-shaped bacterial strain, designated IWT126(T), was isolated from orchardgrass (Dactylis glomerata L.) silage preserved in Hachimantai, Iwate, Japan. The isolate showed growth at 15-45 °C, pH 3.5-7.5 and with 4.0 % (w/v) NaCl. The cell wall peptidoglycan did not contain meso-diaminopimelic acid, and the DNA G+C content was 45.6 mol%. The major cellular fatty acids were C16 : 0 and C19 : 1 cyclo 9,10. Based on 16S rRNA gene sequence similarity, strain IWT126(T) was classified as a member of the genus Lactobacillus and was most closely related to Lactobacillus odoratitofui YIT 11304(T) (98.7 %), Lactobacillus similis JCM 2765(T) (98.5 %), Lactobacillus collinoides JCM 1123(T) (97.6 %), Lactobacillus paracollinoides DSM 15502(T) (97.6 %) and Lactobacillus kimchicus DCY51(T) (96.9 %). Based on sequence analysis of the phenylalanyl-tRNA synthase α-subunit (pheS) gene, strain IWT126(T) was well separated from its phylogenetic neighbours in the genus Lactobacillus. Based on physiological, biochemical and genotypic results, as well as low DNA-DNA relatedness to recognized phylogenetic relatives in the genus Lactobacillus, classification of strain IWT126(T) as a representive of a novel species named Lactobacillus silagei sp. nov. is proposed. The type strain is IWT126(T) ( = JCM 19001(T) = DSM 27022(T)).


Assuntos
Dactylis/microbiologia , Lactobacillus/classificação , Filogenia , Silagem/microbiologia , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Japão , Lactobacillus/genética , Lactobacillus/isolamento & purificação , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , Peptidoglicano/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
11.
Anaerobe ; 23: 109-11, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23891962

RESUMO

Metabolically active microbiota of the porcine terminal ileum mucosa was analyzed by RT-PCR of 16S rRNAs. The majority of 1951 sequences retrieved (24.8%) displayed the closest similarity to segmented filamentous bacteria (SFB). Phylogenetic analysis inferred the host-specific clusters of SFB sequences suggesting the host-specific selection of this group of bacteria.


Assuntos
Bactérias/classificação , Bactérias/isolamento & purificação , Biodiversidade , Íleo/microbiologia , Animais , Análise por Conglomerados , Feminino , Masculino , Filogenia , RNA Ribossômico 16S/genética , Suínos
12.
Int J Syst Evol Microbiol ; 63(Pt 10): 3854-3860, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23687059

RESUMO

Two bacterial strains, designated IWT246(T) and IWT248, were isolated from orchardgrass (Dactylis glomerata L.) silage from Iwate prefecture, Japan, and examined for a taxonomic study. Both organisms were rod-shaped, Gram-stain-positive, catalase-negative, facultatively anaerobic and homofermentative. The cell wall did not contain meso-diaminopimelic acid and the major fatty acids were C18 : 1ω9c and C19 cyclo 9,10/:1. Comparative analyses of 16S rRNA, pheS and rpoA gene sequences revealed that these strains were novel and belonged to the genus Lactobacillus. Based on 16S rRNA gene sequence similarity, the isolates were most closely related to the type strains of the following members of the genus Lactobacillus: Lactobacillus coryniformis subsp. coryniformis (96.7 % similarity), L. coryniformis subsp. torquens (96.6 %), L. bifermentans (95.5 %) and L. rennini (94.1 %). However, the 16S rRNA gene sequences of both IWT246(T) and IWT248 were 99.7 % similar to that of 'Lactobacillus backi' JCM 18665; this name has not been validly published. Genotypic, phenotypic and chemotaxonomic analyses confirmed that these novel strains occupy a unique taxonomic position. DNA-DNA hybridization experiments demonstrated genotypic separation of the novel isolates from related Lactobacillus species. The name Lactobacillus iwatensis sp. nov. is proposed for the novel isolates, with strain IWT246(T) ( = JCM 18838(T) = DSM 26942(T)) as the type strain. Our results also suggest that 'L. backi' does represent a novel Lactobacillus species. The cells did not contain meso-diaminopimelic acid in their cell-wall peptidoglycan and the major fatty acids were C16 : 0, C19 cyclo 9,10/:1 and summed feature 10 (one or more of C18 : 1ω11c, C18 : 1ω9t, C18 : 1ω6t and unknown ECL 17.834). We therefore propose the corrected name Lactobacillus backii sp. nov., with the type strain JCM 18665(T) ( = LMG 23555(T) = DSM 18080(T) = L1062(T)).


Assuntos
Dactylis/microbiologia , Lactobacillus/classificação , Filogenia , Silagem/microbiologia , Técnicas de Tipagem Bacteriana , Parede Celular/química , DNA Bacteriano/genética , Ácidos Graxos/análise , Japão , Lactobacillus/genética , Lactobacillus/isolamento & purificação , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , Peptidoglicano/análise , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
13.
Anim Sci J ; 84(11): 726-31, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23607630

RESUMO

We improved the dry ash procedure for detecting titanium dioxide (TiO2 ) in cattle feces containing chromium oxide [corrected] (Cr(2)O(3) ). First, the effect of amount of sodium sulfate (Na2 SO4 ) on the recovery of TiO2 from cattle feces that contained Cr2 O3 was evaluated. Average recovery of TiO2 at the 2.5 g Na2 SO4 level was significantly higher (P < 0.0001) than that at 0.75 g Na2 SO4 . Second, the effect of Cr2 O3 concentration on the recovery of TiO2 of cattle feces by using two levels of Na2 SO4 addition was examined. The recovery of TiO2 decreased with the increase in the amount of Cr2 O3 at the 0.75 g Na2 SO4 level but was consistently high at 2.5 g Na2 SO4 . Third, the recovery of Cr2 O3 from cattle feces was checked. The recoveries of TiO2 and Cr2 O3 were high enough at the 2.5 g Na2 SO4 level. Fourth, the improved dry ash procedure (5 mL of concentrated H2 SO4 and 2.5 g of Na2 SO4 were used for sample digestion) was compared to the wet ash procedure. Average recovery of TiO2 by the improved dry ash procedure was significantly higher (P = 0.0077) than that by the wet ash procedure. Thus, the improved dry ash procedure can be used for TiO2 analysis in cattle feces containing Cr2 O3 .


Assuntos
Bovinos/metabolismo , Fezes/química , Titânio/análise , Animais , Compostos de Cromo/análise
14.
Int J Syst Evol Microbiol ; 63(Pt 8): 2957-2962, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23378109

RESUMO

The taxonomic position of three Lactobacillus-like micro-organisms (strains SG293(T), SG296 and SG310) isolated from fermented rice grain (Oryza sativa L. subsp. japonica) in Japan was investigated. These heterofermentative lactic acid bacteria were Gram-stain-positive, rod-shaped, facultatively anaerobic, non-motile, non-spore-forming and did not show catalase activity. 16S rRNA gene sequence analysis of strain SG293(T) revealed that the type strains of Lactobacillus malefermentans (98.3 %), Lactobacillus odoratitofui (96.2 %), Lactobacillus similis (96.1 %), Lactobacillus kimchicus (96.1 %), Lactobacillus paracollinoides (95.9 %) and Lactobacillus collinoides (95.7 %) were the closest neighbours. Additional phylogenetic analysis on the basis of pheS and rpoA gene sequences, as well as biochemical and physiological characteristics, indicated that these three strains were members of the genus Lactobacillus and that the novel isolates had a unique taxonomic position. The predominant cellular fatty acids were C18 : 1ω9c and C19 : 1 cyclo 9,10. Because low DNA-DNA hybridization values among the isolates and Lactobacillus malefermentans JCM 12497(T) were observed, it is proposed that these unidentified isolates be classified as a novel species of the genus Lactobacillus, Lactobacillus oryzae sp. nov. The type strain is SG293(T) (= JCM 18671(T) = DSM 26518(T)).


Assuntos
Fermentação , Lactobacillus/classificação , Oryza/microbiologia , Filogenia , Técnicas de Tipagem Bacteriana , DNA Bacteriano/genética , Ácidos Graxos/análise , Microbiologia de Alimentos , Japão , Lactobacillus/genética , Lactobacillus/isolamento & purificação , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
15.
J Biosci Bioeng ; 115(1): 64-70, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22921519

RESUMO

Caldicellulosiruptor bescii is a cellulolytic/hemicellulolytic anaerobe, which extracellularly secretes various proteins, including multidomain cellulases with two-catalytic domains, for plant biomass degradation. Degradation by C. bescii cells has been well characterized, but degradation by the cell-free extracellular cellulase/hemicellulase system (CEC) of C. bescii has not been as well studied. In the present study, C. bescii CEC was prepared from cell-free culture supernatant, and the degradation properties for defined substrates and non-pretreated plant biomass were characterized. Four multidomain cellulases (Cbes_1857, Cbes_1859, Cbes_1865, and Cbes_1867), composed of the glycoside hydrolase families 5, 9, 10, 44, and 48, were the major enzymes identified in the CEC by mass spectrometry. The CEC degraded xylan, mannose-based substrates, ß-1,4-linked glucans, including microcrystalline cellulose (Avicel), and non-pretreated timothy grass and rice straw. However, degradation of chitin, pectin, dextran, and wheat starch was not observed. The optimum temperatures for degradation activities were 75°C for timothy grass and Avicel, 85°C for carboxylmethyl cellulose, and >85°C for xylan. The optimum pH for these substrates was 5-6. The degradation activities were compared with a CEC derived from the fungus Trichoderma reesei, the most common enzyme used for plant biomass saccharification. The amounts of degraded Avicel, timothy grass, and rice straw by C. bescii CEC were 2.2-2.4-fold larger than those of T. reesei CEC. The high hydrolytic activity of C. bescii CEC might be attributed to the two-catalytic domain architecture of the cellulases.


Assuntos
Biomassa , Celulase/metabolismo , Celulose/metabolismo , Glicosídeo Hidrolases/metabolismo , Bactérias Gram-Positivas/enzimologia , Plantas/metabolismo , Glucanos/metabolismo , Concentração de Íons de Hidrogênio , Hidrólise , Oryza/química , Oryza/metabolismo , Phleum/química , Phleum/metabolismo , Plantas/química , Temperatura , Trichoderma/enzimologia
16.
Int J Syst Evol Microbiol ; 63(Pt 4): 1417-1420, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22843715

RESUMO

A taxonomic study was conducted on two Gram-reaction-positive, catalase-negative, irregular short-rod-shaped or coccoid lactic acid bacteria, designated strains SG25(T) and SG23, that were isolated from grains of fermented Japanese rice (Oryza sativa L. subsp. japonica). A phylogenetic analysis based on 16S rRNA gene sequence data clearly showed that the strains belonged to the genus Weissella and were most closely related to Weissella soli LMG 20113(T) (with a sequence similarity of 96.9 % for each novel strain). The peptidoglycan of each strain contained the amino acids glutamic acid, lysine, serine and alanine in a molar ratio of 1.0 : 1.2 : 0.5 : 3.0, respectively. On the basis of the unusual phenotypic characteristics of the novel strains and the low levels of DNA-DNA relatedness recorded between each novel strain and Weissella soli JCM 12536(T), strains SG25(T) and SG23 represent a single novel species in the genus Weissella, for which the name Weissella oryzae sp. nov. is proposed. The type strain is SG25(T) ( = JCM 18191(T)  = DSM 25784(T)).


Assuntos
Oryza/microbiologia , Filogenia , Weissella/classificação , Técnicas de Tipagem Bacteriana , DNA Bacteriano/genética , Ácidos Graxos/análise , Fermentação , Dados de Sequência Molecular , Peptidoglicano/análise , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Weissella/genética , Weissella/isolamento & purificação
17.
Int J Syst Evol Microbiol ; 63(Pt 7): 2526-2531, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23223820

RESUMO

Four strains of Gram-positive, non-spore-forming, rod-shaped, catalase-negative and non-motile lactic acid bacteria, LOOC260(T), LOOC253, LOOC273 and LOOC279, were isolated from timothy grass (Phleum pratense L.) silage produced in Hokkaido, a subarctic region of Japan. These isolates grew at 4-37 °C, indicating the psychrotolerant nature of these strains. Phylogenetic analysis on the basis of 16S rRNA and pheS gene sequences, as well as biochemical and physiological characteristics, indicated that these four strains were members of the genus Lactobacillus. 16S rRNA gene sequence analysis of strain LOOC260(T) demonstrated that the closest neighbours were the type strains of Lactobacillus suebicus (97.7 %), Lactobacillus oligofermentans (96.7 %) and Lactobacillus vaccinostercus (96.7 %). Strain LOOC260(T) showed low levels of DNA-DNA association with Lactobacillus suebicus JCM 9504(T) (14.7 ± 3.5 %), Lactobacillus oligofermentans JCM 16175(T) (15.1 ± 4.8 %) and Lactobacillus vaccinostercus JCM 1716(T) (10.7 ± 3.0 %). The cell wall contained meso-diaminopimelic acid and the major fatty acids were C18 : 1ω9c and C19 : 1 cyclo 9,10. On the basis of phenotypic, physiological and phylogenetic evidence, these isolates represent a novel species of the genus Lactobacillus, for which the name Lactobacillus hokkaidonensis sp. nov. is proposed. The type strain is LOOC260(T) ( = JCM 18461(T) = DSM 26202(T)).


Assuntos
Lactobacillus/classificação , Phleum/microbiologia , Filogenia , Silagem/microbiologia , Técnicas de Tipagem Bacteriana , DNA Bacteriano/genética , Ácidos Graxos/análise , Genes Bacterianos , Japão , Lactobacillus/genética , Lactobacillus/isolamento & purificação , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
18.
Anim Sci J ; 83(11): 727-34, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23126325

RESUMO

The influence of rumen protozoa on the composition of rumen methanogens was studied by using seven growing Holstein cattle divided into two groups: four faunated and three unfaunated. 16S ribosomal RNA gene (rDNA) and methyl coenzyme-M reductase (MCR) α subunit (mcrA) gene clonal libraries were constructed. The results of each analysis showed that Methanobacteriales was dominant in the rumen of both groups. By mcrA gene analysis, 22.1% of unfaunated clones were classified into unfaunated group 1, which was not detected from faunated cattle. The 16S rRNA gene analysis showed that the number of operational taxonomic units was higher in unfaunated than faunated cattle, suggesting the diversity of methanogens tended to be higher by the removal of protozoa. The results of the LIBSHUFF program indicated that the 16S rRNA gene and mcrA gene clone libraries for the faunated group differed from those for the unfaunated group (P = 0.001). It was suggested that the presence of protozoa strongly affected the composition of rumen methanogens.


Assuntos
Bovinos/microbiologia , Bovinos/parasitologia , Cilióforos/fisiologia , Methanobacteriales/genética , Interações Microbianas , Oxirredutases/genética , Filogenia , RNA Ribossômico 16S/genética , Rúmen/microbiologia , Rúmen/parasitologia , Animais , Biblioteca Gênica , Methanobacteriales/classificação , Dados de Sequência Molecular
19.
FEMS Microbiol Lett ; 337(2): 112-9, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23003205

RESUMO

Paddy rice has been of particular interest as a forage crop in Japan. In this study, the isolated strains TO1000, TO1001, TO1002, and TO1003 were characterized by phenotypic and genotypic approaches. These strains were identified as Lactobacillus plantarum subsp. plantarum by species-specific PCR. Phenotypic characteristics varied among different strains of the same subspecies, and the strains represented unique and diverse phenotypes related to fermentation factors, such as carbohydrate assimilation and range of pH and temperature allowing growth. PCR analysis revealed that the patterns of presence/absence of known plantaricin genes differed in a strain-specific manner. Using these strains as inoculants for preparation of whole crop paddy rice silage, fermentation quality was significantly improved, as shown by lower pH, higher lactic acid content, and inhibition of the growth of undesirable microorganisms such as molds, coliform bacteria, and clostridia, after 30 and 60 days of storage, with effectiveness differing from strain to strain. These observations suggest that suitable candidates for bacterial inoculants in silage preparation should be screened at the strain level. Strain TO1002 may be useful for producing silage inoculants for the production of well-preserved whole crop paddy rice silage.


Assuntos
Lactobacillus plantarum/metabolismo , Oryza/metabolismo , Oryza/microbiologia , Silagem/microbiologia , Técnicas de Tipagem Bacteriana , DNA Bacteriano/genética , Fermentação , Japão , Lactobacillus plantarum/classificação , Lactobacillus plantarum/crescimento & desenvolvimento , Lactobacillus plantarum/isolamento & purificação , Reação em Cadeia da Polimerase
20.
Dent Mater J ; 29(4): 381-91, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20668358

RESUMO

The effects of sandblasting media and steam cleaning treatment after sandblast were examined on tensile bond strength of porcelain to titanium. The use of the commercially available silica-coated alumina particles for sandblast was significantly effective for increasing bond strength than the conventional alumina. It might be due to the increased surface roughness and existence of remaining silica on titanium surface. Additional application of the steam cleaning on titanium surface after sandblasting could make the surface configuration clear in SEM by removing some sandblasted particles loosely embedded in titanium as well as the debris and oily contaminants. The resultant bond strength was significantly improved to reach almost the maximum strength of this porcelain-titanium system regardless of the kind of sandblasting media used, which was confirmed by the observation of the failure mode showing that most of the fracture surface was occupied by cohesive failure in porcelain.


Assuntos
Colagem Dentária , Corrosão Dentária/métodos , Materiais Dentários/química , Porcelana Dentária/química , Vapor , Titânio/química , Óxido de Alumínio/química , Cimentos Dentários/química , Polimento Dentário , Análise do Estresse Dentário , Microanálise por Sonda Eletrônica , Humanos , Teste de Materiais , Microscopia Eletrônica de Varredura , Pressão , Dióxido de Silício/química , Estresse Mecânico , Propriedades de Superfície , Resistência à Tração , Fatores de Tempo
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