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1.
Waste Manag ; 135: 130-139, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34496309

RESUMO

Aerobic composting is a promising alternative for the recycling of rice straw (RS), and an applicable nitrogen source is necessary to improve the process. The aim of this study was to compare the performance and microbial community dynamics of RS composting using urea or protein hydrolysate from leather waste (PHL) as a nitrogen source. Results showed that PHL addition achieved a faster temperature increase rate at start-up (1.85 ℃·h-1 vs 1.07 ℃·h-1), higher volatile solid degradation efficiency (48.04% vs 46.98%), and greater germination indices (111.72% vs 89.87%) in the end products, as compared to urea. The major bacterial phyla included Proteobacteria, Firmicutes, Bacteroidetes, and Actinobacteria in both composting processes. Although the bacterial communities in both processes succeeded in a similar pattern according to different composting phases, PHL addition accelerated the succession rate of the microbial community. Co-occurrence network analysis revealed that bacterial community composition was strongly correlated with physicochemical properties such as dissolved organic carbon (DOC), NH4+, pH, temperature, and total nitrogen (TN) content. These results proved the potential of using PHL as a nitrogen source to improve the RS composting process.


Assuntos
Compostagem , Microbiota , Oryza , Esterco , Nitrogênio/análise , Hidrolisados de Proteína , Solo , Ureia
2.
Artigo em Inglês | MEDLINE | ID: mdl-34499596

RESUMO

A Gram-stain-negative, coccus-shaped, obligately anaerobic, non-motile and non-spore-forming bacterium, designated strain JN500902T, was isolated from the mud in a fermentation cellar used continuously over 30 years for Chinese strong-flavour baijiu production. Colonies were white, circular, convex and smooth-edged. Growth was observed at 20-40 °C (optimum, 37 °C), at pH 5.0-10 (optimum, pH 7.5), with 0-2 % (w/v) NaCl and with 0-4 % (v/v) ethanol. The Biolog assay demonstrated positive reactions of strain JN500902T in the metabolism of l-fucose and pyruvate. The predominant cellular fatty acids (>10 %) consisted of C16 : 0 and C14 : 0. The major end metabolites of strain JN500902T were acetic acid and ethanol when incubated anaerobically in liquid reinforced clostridial medium. Acetate was the major organic acid end product. The complete genome size of strain JN500902T was 3 420 321 bp with 3327 identified genes. The G+C content was 43.5 mol%. Phylogenetic analysis based on 16S rRNA gene sequences affiliated strain JN500902T with the family Lachnospiraceae, having low sequence similarity (92.8 %) to the nearest type strain, Syntrophococcus sucromutans DSM 3224T and forming a clearly distinct branch. Core genome phylogenetic analysis of the isolate and 134 strains belonging to the family Lachnospiraceae also revealed that strain JN500902T was well-separated from other genera of this family as a monophyletic clade. The average nucleotide identity and amino acid identity values between strain JN500902T and 134 Lachnospiraceae strains were less than 74 and 65 %, respectively. Considering its polyphasic characteristics, strain JN500902T represents a novel genus and species within the family Lachnospiraceae, for which the name Novisyntrophococcus fermenticellae gen. nov., sp. nov. is proposed. The type strain is JN500902T (=CICC 24502T=JCM 33939T).


Assuntos
Clostridiales/classificação , Fermentação , Filogenia , Microbiologia do Solo , Anaerobiose , Técnicas de Tipagem Bacteriana , Composição de Bases , China , Clostridiales/isolamento & purificação , DNA Bacteriano/genética , Ácidos Graxos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
3.
Food Res Int ; 147: 110449, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34399451

RESUMO

Mud cellars have long been used as anaerobic bioreactors for the fermentation of Chinese strong-flavor Baijiu, where starchy raw materials (mainly sorghum) are metabolized to ethanol and various flavor compounds by multi-species microorganisms. Jiupei (fermented grains) and pit mud are two spatially linked microbial habitats in the mud cellar, yet their metabolic division of labor remains unclear. Here, we investigated the changes in environmental variables (e.g., temperature, oxygen, pH), key metabolites (e.g., ethanol, organic acids) and microbial communities in jiupei and pit mud during fermentation. Jiupei (low pH, high ethanol) and pit mud (neutral pH) provided two habitats with distinctly different environmental conditions for microbial growth. Lactic acid accumulated in jiupei, while butyric and hexanoic acids were mainly produced by microbes inhabiting the pit mud. Biomass analysis using quantitative real-time PCR showed that bacteria dominated the microbial consortia during fermentation, moreover cluster and principal coordinate analysis (PCoA) analysis showed that the bacterial communities of jiupei and pit mud were significantly divergent. The bacterial community diversity of jiupei decreased significantly during the fermentation process, and was relatively stable in pit mud. Lactobacillus dominated the jiupei bacterial community, and its relative abundance reached 98.0% at the end of fermentation. Clostridia (relative abundance: 42.9-85.5%) was the most abundant bacteria in pit mud, mainly distributed in the genus Hydrogenispora (5.3-68.4%). Fungal communities of jiupei and pit mud showed a similar succession pattern, and Kazachstania, Aspergillus and Thermoascus were the predominant genera. PICRUSt analysis demonstrated that enzymes participating in the biosynthesis of acetic and lactic acid were mainly enriched in jiupei samples, while the bacterial community in the pit mud displayed greater potential for butyric and hexanoic acid synthesis. Assays from an in vitro simulated fermentation further validated the roles of jiupei microbiota in acetic and lactic acid production, and these acids were subsequently metabolized to butyric and hexanoic acid by the pit mud microbiota. This work has demonstrated the synergistic cooperation between the microbial communities of jiupei and pit mud for the representative flavor formation of strong-flavor Baijiu.


Assuntos
Consórcios Microbianos , Microbiota , Bebidas Alcoólicas/análise , Bactérias/genética , Fermentação
4.
Bioresour Technol ; 337: 125492, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34320771

RESUMO

This study evaluated the impact of biochar addition on nitrogen (N) loss and the process period during distilled grain waste (DGW) composting. Results from the five treatments (0, 5, 10, 15, and 20% biochar addition) indicated that 10% biochar addition (DB10) was optimal, resulting in the lowest N loss, 25.69% vs. 40.01% in the control treatment. Moreover, the DGW composting period was shortened by approximately 14 days by biochar addition. The composition of the microbial community was not significantly altered with biochar addition in each phase, however, it did accelerate the microbial succession during DGW composting. N metabolism pathway prediction revealed that biochar addition enhanced nitrification and inhibited denitrification, and the latter phenomenon was the main reason for reducing N loss during DGW composting. Based on the above results, a potential mechanism model for biochar addition to reduce N loss during the DGW composting process was established.


Assuntos
Compostagem , Microbiota , Carvão Vegetal , Esterco , Nitrogênio , Solo
5.
Appl Environ Microbiol ; 87(17): e0088521, 2021 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-34160281

RESUMO

The mud cellar creates a unique microenvironment for the fermentation of strong-flavor baijiu (SFB). Recent research and long-term practice have highlighted the key roles of microbes inhabiting pit mud in the formation of SFB's characteristic flavor. A positive correlation between the quality of SFB and cellar age was extracted from practice; however, the evolutionary patterns of pit mud microbiome and driving factors remain unclear. Here, based on the variation regularity analysis of microbial community structure and metabolites of samples from cellars of different ages (∼30/100/300 years), we further investigated the effects of lactate and acetate (main microbial metabolites in fermented grains) on modulating the pit mud microbiome. Esters (50.3% to 64.5%) dominated the volatile compounds identified in pit mud, and contents of the four typical acids (lactate, hexanoate, acetate, and butyrate) increased with cellar age. Bacteria (9.5 to 10.4 log10 [lg] copies/g) and archaea (8.3 to 9.1 lg copies/g) mainly constituted pit mud microbiota, respectively dominated by Clostridia (39.7% to 81.2%) and Methanomicrobia (32.8% to 92.9%). An upward trend with cellar age characterized the relative and absolute abundance of the most predominant bacterial and archaeal genera, Caproiciproducens and Methanosarcina. Correlation analysis revealed significantly (P < 0.05) positive relationships between the two genera and major metabolites. Anaerobic fermentation with acetate and lactate as carbon sources enhanced the enrichment of Clostridia, and furthermore, the relative abundance of Caproiciproducens (40.9%) significantly increased after 15-day fed-batch fermentation with lactate compared with the initial pit mud (0.22%). This work presents a directional evolutionary pattern of pit mud microbial consortia and provides an alternative way to accelerate the enrichment of functional microbes. IMPORTANCE The solid-state anaerobic fermentation in a mud cellar is the most typical feature of strong-flavor baijiu (SFB). Metabolites produced by microbes inhabiting pit mud are crucial to create the unique flavor of SFB. Accordingly, craftspeople have always highlighted the importance of the pit mud microbiome and concluded by centuries of practice that the production rate of high-quality baijiu increases with cellar age. To deepen the understanding of the pit mud microbiome, we determined the microbial community and metabolites of different-aged pit mud, inferred the main functional groups, and explored the forces driving the microbial community evolution through metagenomic, metabolomic, and multivariate statistical analyses. The results showed that the microbial consortia of pit mud presented a regular and directional evolutionary pattern under the impact of continuous batch-to-batch brewing activities. This work provides insight into the key roles of the pit mud microbiome in SFB production and supports the production optimization of high-quality pit mud.


Assuntos
Archaea/isolamento & purificação , Bactérias/isolamento & purificação , Argila/microbiologia , Aromatizantes/metabolismo , Microbiota , Vinho/análise , Archaea/classificação , Archaea/genética , Archaea/metabolismo , Bactérias/classificação , Bactérias/genética , Bactérias/metabolismo , China , Fermentação , Aromatizantes/análise , Armazenamento de Alimentos/instrumentação , Vinho/microbiologia
7.
Food Microbiol ; 98: 103766, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33875202

RESUMO

Daqu, a brick-shaped product spontaneously fermented under an open environment, has been regarded as the starter of fermentation, raw enzyme preparation and raw materials for baijiu production. However, its contribution in baijiu fermentation has not been fully elaborated yet. Here, the effects of daqu microbiota on baijiu fermentation were investigated under both field-scale and lab-scale conditions. In field-scale baijiu fermentation, the dominant daqu microbes (average relative abundance>10.0%), including unclassified_Leuconostocaceae, Thermoascus, and Thermomyces, tended to dominate the early stage (0-7 d). However, the rare daqu microbes (average relative abundance <0.1%, e.g., Kazachstania) tended to dominate the middle and late stages (11-40 d). In addition, some genera showed differences in species diversity between daqu and fermented grains. The average relative abundance of Lactobacillus was over 75% during baijiu fermentation, and most of them were affiliated with Lactobacillus acetotolerans, while Lactobacillus crustorum dominated the Lactobacillus OTUs in daqu. The similar patterns were also observed during lab-scale baijiu fermentation. The results of function prediction showed the enriched metabolic pathways were associated with glycolysis and long-chain fatty acid esters in baijiu fermentation. These results improved the understanding of daqu microbiota function during baijiu fermentation and provided a basic theory to support the regulation of baijiu production.


Assuntos
Bebidas Alcoólicas/microbiologia , Lactobacillus/isolamento & purificação , Lactobacillus/metabolismo , Microbiota , China , Fermentação , Microbiologia de Alimentos , Lactobacillus/classificação , Lactobacillus/genética
8.
Food Res Int ; 140: 110037, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33648263

RESUMO

As a widely used Asian starter culture, the quality of daqu can significantly affect the organoleptic characteristics of the final products, yet the microbial metabolic network involved in flavor development remains unclear. This study aims to investigate that network based on the dynamics of physicochemical properties, microbial community, and volatile compounds in medium-temperature daqu (MT-daqu) during spontaneous fermentation. Analyses using the metagenomic data set facilitated the gene repertoire overview of this ecosystem, indicating that Lactobacillales (mainly Weissella, Lactobacillus, and Pediococcus), Mucorales (mainly Lichtheimia), and Eurotiales (mainly Aspergillus, Rasamsonia and Byssochlamys) were the potential predominant populations successively responsible for the production of lytic enzymes and flavor precursors/compounds in MT-daqu. Flavor-relevant pathways were found to exist in multiple species, but only bacteria showed the potential to participate in butane-2,3-diol (e.g. Weissella, Lactobacillus, and Staphylococcus) and butanoate (Thermoactinomyces) metabolism, and only fungi were potentially involved in biosynthesis of guaiacol (Byssochlamys) and 4-vinylguaiacol (Aspergillus). Furthermore, a combined analysis revealed that the acidic thermal environment present in early phases was mainly due to the catabolic activities of Lactobacillales and Lichtheimia, which could contribute to the effective self-domestication of microbiota. The study helps elucidate the different metabolic roles of microorganisms and disclose the formation mechanism of daqu's partial functions, namely providing various aromatic substances/precursors and enzymes.


Assuntos
Metagenômica , Microbiota , Bebidas Alcoólicas/análise , Redes e Vias Metabólicas , Microbiota/genética , Temperatura
9.
J Sci Food Agric ; 100(8): 3544-3553, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32242927

RESUMO

BACKGROUND: Jiuqu are vital saccharifying and fermenting agents for Chinese fermented foods. Natural ventilation during Jiuqu fermentation causes changes in temperature, oxygen and moisture content, resulting in mass and heat gradients from the outer to inner areas of Jiuqu blocks. In the present study, microbiota stratification in Jiuqu was investigated by single molecule real-time sequencing and culture isolation. The contributors of Bacillus to amylase activity of Jiuqu and the dynamics of their biomass during Jiuqu fermentation were also analyzed. RESULTS: The dominant orders, genera and species between the inner and outer layers of Huangjiu qu (HJQ) were similar, although they displayed greater variance in two layers of Baijiu qu (BJQ). Bacillus possessed the highest diversity (including 27 species) in Jiuqu. Bacillus licheniformis, Bacillus altitudinis, Bacillus subtilis, Bacillus amyloliquefaciens and Bacillus megaterium were most prevalent in HJQ, whereas B. licheniformis, B. amyloliquefaciens and Bacillus cereus were dominant in BJQ. Isolates of B. amyloliquefaciens, B. subtilis and B. cereus exhibited high activities of amylase and glucoamylase. Quantification of Bacillus members possessing genes of α-amylase revealed that B. cereus and B. licheniformis were the most dominant microbes to secret α-amylase in Jiuqu and their biomass were increasing during Jiuqu fermentation. CONCLUSION: The present study demonstrates the microbial distribution in different layers of Jiuqu and clarifies the Bacillus species processing the activity of α-amylase. These results will help industries control the quality of Jiuqu by rationally selecting starters and optimizing their microbiota. © 2020 Society of Chemical Industry.


Assuntos
Bacillus/metabolismo , Proteínas de Bactérias/metabolismo , Microbiota , Oryza/microbiologia , Amilases/genética , Amilases/metabolismo , Bacillus/classificação , Bacillus/enzimologia , Bacillus/genética , Proteínas de Bactérias/genética , Fermentação , Alimentos e Bebidas Fermentados/microbiologia , Microbiologia de Alimentos
10.
Huan Jing Ke Xue ; 41(1): 438-448, 2020 Jan 08.
Artigo em Chinês | MEDLINE | ID: mdl-31854947

RESUMO

We use 3487 surface soil samples, 35 soil profile samples, and 93 agricultural products and root soil samples obtained from the southeastern Tarim basin, Xinjiang, northwestern China (Ruoqiang County and Qiemo County, Bayingguo Mongolia Autonomous Prefecture, and Minfeng County and Yutian County, Hetian Prefecture) to assess As contamination. Multivariate statistical analysis, geostatistics, and global information system (GIS) techniques are used to study:the spatial distribution characteristics of soil As, the effects of various agricultural products on As enrichment, and to compare the characteristics of the As content of agricultural products and root soils in spatially significantly and non-significantly autocorrelated regions. The As content of soil samples were relatively low, and the average As contents determined for agricultural land and non-agricultural land were 9.81 mg·kg-1 and 7.94 mg·kg-1, respectively. We found that 568 surface soil samples (16.3% of all samples) had an As content that exceeded Xinjiang soil background values (11.2 mg·kg-1) and that five samples exceeded the risk screening values (25 mg·kg-1). The Moran's indexes of spatial autocorrelation were>0, and the main aggregation types of spatial autocorrelation of soil As were high-high and low-low types, with the zone of the high-high type being mainly located in the agricultural land of each county. A GIS spatial distribution map showed that the high value area of soil As content presented a flaky or island-like scattered distribution. The standard deviation ellipses showed that the trend direction of soil As content in:Ruoqiang County was from north to south, Qiemo County and Minfeng County were both from southwest to northeast, and Yutian County was from northwest to southeast. The As content of the vertical profiles of the agricultural land in Ruoqiang County fluctuated from the surface to depth, whereas those of other counties were relatively stable. The As enrichment ability of crops was ranked as:root vegetables > walnuts > wheat > corn > red dates. The As contents of corn and red dates showed a significant positive correlation with that of the root soil. There was no significant difference in the As content of agricultural products between significant autocorrelation zones and non-significant autocorrelation zones, whereas there was a significant difference in the As content of root soils.

11.
Artigo em Inglês | MEDLINE | ID: mdl-31652978

RESUMO

This study aimed to explore the relationship between physical exercise (PE) and mobile phone dependence (MPD) in Chinese university students and verify the potential role of self-control (SC) in mediating the decrease of MPD by PE. Through the quota sampling, 608 students that complied with the requirements were surveyed from 10 universities in China. PE, MPD, and SC were assessed using standard scales. For data analysis, t-tests, correlation analysis, hierarchical regression, and regression analysis were carried out in turn. The results showed significant gender differences in PE, MPD, and SC. For male students, the level of PE and score of SC were higher than those in females, yet the MPD score was lower. PE and SC were negatively related to MPD (r = -0.124, p < 0.01; r = -0.563, p < 0.001), so both could remarkably predict MPD (ß = -1.00, p < 0.05; ß = -0.552, p < 0.001). Gender was also a significant predictor for MPD (ß = 0.089, p < 0.05). PE could, to some extent, decrease MPD, in which SC played a significant mediating role-its mediating effect accounted for nearly 71% of the total effect. The present study shows that PE is negatively correlated with MPD, and SC mediates the decrease of MPD by PE for university students in China. This indicates that the improvement of SC by PE could be a highly trustworthy and practicable way to effectively address the issue of MPD in university students or other young people across the world.


Assuntos
Grupo com Ancestrais do Continente Asiático/psicologia , Comportamento Aditivo/terapia , Telefone Celular , Terapia por Exercício/métodos , Exercício Físico/psicologia , Autocontrole/psicologia , Estudantes/psicologia , Adolescente , Adulto , China , Feminino , Humanos , Masculino , Fatores Sexuais , Inquéritos e Questionários , Universidades , Adulto Jovem
12.
Front Microbiol ; 10: 1397, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31316481

RESUMO

Butyrate, one of the key aroma compounds in Luzhou-flavor baijiu, is synthesized through two alternative pathways: butyrate kinase (buk) and butyryl-CoA: acetate CoA-transferase (but). A lack of knowledge of butyrate-producing microorganisms hinders our ability to understand the flavor formation mechanism of baijiu. Here, temporal dynamics of microbial metabolic profiling in fermented grains (FG) was explored via PICRUSt based on 16S rRNA gene sequences. We found Bacilli and Bacteroidia were the major potential butyrate producers in buk pathway at the beginning of fermentation, while later Clostridia dominated the two pathways. Clone library analysis also revealed that Clostridia (~73% OTUs) was predominant in buk pathway throughout fermentation, followed by Bacilli and Bacteroidia, and but pathway was merely possessed by Clostridia. Afterward, Clostridia-specific 16S rRNA gene sequencing demonstrated Clostridium might be the major butyrate-producing genus in two pathways, which was subsequently evaluated using culture approach. Seventeen Clostridium species were isolated from FG based on 16S rRNA gene sequence-guided medium prediction method. Profiles of short-chain fatty acids and but and buk genes in these species demonstrated phylogenetic and functional diversities of butyrate-producing Clostridium in FG. These findings add to illustrate the diversity of potential butyrate producers during brewing and provide a workflow for targeting functional microbes in complex microbial community.

13.
Int J Food Microbiol ; 297: 41-50, 2019 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-30878841

RESUMO

Butyrate and its derivates pertain to the key aroma contributors of strong-flavour baijiu, a kind of Chinese liquors, that is produced from grains by solid-state multispecies anaerobic fermentation in a mud cellar. Microbes inhabiting in the fermentation pit mud largely determines baijiu's flavour and quality. In order to shed light on the microbial functional groups driving butyrate production in pit mud, clone library analysis was firstly performed and the results demonstrated that Clostridia (relative abundance: 50%) and Bacilli (37%) were major groups possessing butyrate kinase (buk) pathway and Clostridia (98%) dominated butyryl-CoA:acetate CoA-transferase (but) pathway. According to Clostridial specific-16S rRNA gene sequencing analysis, we found the resilience character of Clostridial community in pit mud. Amongst Clostridial groups, 32.0% of the sequences were grouped into Clostridiales incertae sedis, followed by Heliobacteriaceae (18.3%) and Clostridiaceae 1 (8.4%). Moreover, Hydrogenispora, Sedimentibacter and Clostridium were the top three abundant genera. Relative abundance of Hydrogenispora was higher in the late days of fermentation, while Sedimentibacter exhibited higher proportion in the early days. Different from the previous studies using universal bacterial primer sets, Hydrogenispora was first reported as one dominant genus in pit mud. As for the reported potential butyrate producer Clostridium, nineteen species were obtained and ten of them were first isolated from the pit mud. Amongst them, buk was identified in eleven species by PCR analysis, while but was identified in the other seven, indicating the species-specific butyrate synthesis pathways of Clostridium. This study provides a perspective on targeting and isolating specific functional microbes in baijiu microbiota with the gene sequence-based medium prediction method.


Assuntos
Bebidas Alcoólicas , Clostridium/enzimologia , Clostridium/genética , Fermentação , Microbiologia do Solo , Bebidas Alcoólicas/microbiologia , Bacillus/enzimologia , Bacillus/genética , Butiratos/metabolismo , Microbiota/genética , RNA Ribossômico 16S/genética
14.
Int J Syst Evol Microbiol ; 69(3): 859-865, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30735112

RESUMO

A novel Gram-stain-positive, rod-shaped, obligately anaerobic, non-motile, spore-forming and binary fission encapsulated bacterium, designated strain JN500901T, was isolated from a mud cellar which has been continuously used for the fermentation of Chinese strong-flavour baijiu for over 100 years. Growth of JN500901Toccurred at pH 4.5-8.0 (optimum, pH 5.0), 20-40 °C (37 °C), 0-2 % (w/v) NaCl and 0-10 % (v/v) ethanol. The Biolog assay revealed that strain JN500901T metabolized d-fructose, l-fucose, isomaltulose and l-rhamnose among the 95 studied carbon sources. p-Cresol was the predominant volatile metabolite in the fermentation broth of strain JN500901T incubated in liquid reinforced clostridial medium under anaerobic conditions. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain JN500901T belongs to Clostridiumsensu stricto, and shared the highest sequence similarity to Clostridiumcarboxidivorans DSM 15243T (94.2 %), followed by Clostridiumscatologenes DSM 757T (94.1 %). The dominant cellular fatty acids (>10 %) were C16 : 0 FAME (36.6 %), C19 : 0 cyc 9,10 DMA (19.8 %) and C16 : 1 cis 9 DMA (11.8 %). The complete genome of strain JN500901T contained a circular chromosome of 2.812 Mb with 2611 genes and 31.0 mol% G+C content. Comparative genome analysis of the strain JN500901T, Clostridiumcarboxidivorans DSM 15243T and Clostridiumscatologenes DSM 757T revealed 74.5 and 74.8 % average nucleotide identity, respectively. Based on the phenotypic, biochemical and phylogenetic analyses presented here, strain JN500901T is considered to be a novel species of the genus Clostridiumsensustricto, for which the name Clostridium fermenticellae sp. nov. is proposed. The type strain is JN500901T (=CICC 24501T=JCM 32827T).


Assuntos
Bebidas Alcoólicas , Clostridium/classificação , Filogenia , Microbiologia do Solo , Técnicas de Tipagem Bacteriana , Composição de Bases , China , Clostridium/isolamento & purificação , DNA Bacteriano/genética , Etanol , Ácidos Graxos/química , Fermentação , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
15.
Life Sci ; 218: 153-164, 2019 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-30582950

RESUMO

This review aims to systematically review and synthesize scientific evidence for the influence of air pollution exposure and outdoor exercise on health. We conducted a literature search in the PubMed, Cochrane, EMBASE, and Web of Science for articles that evaluated the combination effect of air pollution exposure and exercise on health. Questionnaires regarding exposure history, or studies examining indoor air pollution were excluded. Each included study needs to have clear exercise intervention plan. The pooled estimates of the combination effect of air pollution exposure and outdoor exercise on health were calculated in the meta-analysis. The quality of each included study was assessed and the quality of evidence for each outcome assessed in the meta-analysis was also measured. Twenty-five studies were identified. Six studies addressed ozone exposure, four diesel exhaust exposure, six traffic-related air pollution, ten particulate matter (PM) exposure. Only peak expiratory flow (effect size [ES] = -0.238, 95% confidence interval [CI] = -0.389, -0.088) was found to be significantly decreased after exercise intervention in a polluted environment in the meta-analysis. Seven studies reported exposure to air pollutant during exercise was associated with an increased risk of airway inflammation and decrements in pulmonary function. Six studies discovered that exposure of traffic pollution or high PM during exercise may contribute to changes in blood pressure, systemic conduit artery function and micro-vascular function. The combination effect of air pollution and exercise was found to be associated with the increased risk of potential health problems of cardiopulmonary function, immune function, and exercise performance.


Assuntos
Poluentes Atmosféricos/efeitos adversos , Exposição Ambiental/efeitos adversos , Exercício Físico , Pneumonia/etiologia , Humanos
16.
Stem Cells Dev ; 28(4): 258-267, 2019 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-30526386

RESUMO

Human embryonic stem cells (hESCs) have the potential to differentiate along the retinal lineage. We have efficiently differentiated human pluripotent stem cells into optic cup-like structures by using a novel retinal differentiation medium (RDM). The purpose of this study was to determine whether the retinal progenitor cells (RPCs) derived from hESCs can integrate into the host retina and differentiate into retinal ganglion cells (RGCs) in vivo. In this study, hESCs (H9-GFP) were induced to differentiate into optic cup-like structures by using our novel differentiation system. The RPCs extracted from the optic cup-like structures were transplanted into the vitreous cavity of N-methyl-d-aspartic acid-treated mice. Sham-treated eyes received the same amount of RDM. The host retinas were analyzed by triple immunofluorescence on the fourth and fifth weeks after transplantation. The optic cup-like structures were efficiently differentiated from hESCs by using our novel differentiation system in vitro for 6-8 weeks. The RPCs extracted from the optic cup-like structures migrated and integrated into the ganglion cell layer (GCL) of the host retina. Furthermore, the remaining transplanted cells were spread over the GCL and had a complementary distribution with host residual RGCs in the GCL of the mouse retina. Surprisingly, some of the transplanted cells expressed the RGC-specific marker Brn3a. These findings demonstrated that the RPCs derived from hESCs could integrate into the host GCL and differentiate into retinal ganglion-like cells in vivo, suggesting that RPCs can be used as an ideal source in supplying countless RGC and embryonic stem cell-based replacement therapies may be a promising treatment to restore vision in patients with degenerative retinal diseases.


Assuntos
Células-Tronco Embrionárias Humanas/citologia , Células-Tronco Neurais/transplante , Neurogênese , Células Ganglionares da Retina/citologia , Transplante de Células-Tronco/métodos , Animais , Linhagem Celular , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Células-Tronco Neurais/citologia , Células-Tronco Neurais/metabolismo , Células Ganglionares da Retina/metabolismo , Fator de Transcrição Brn-3A/genética , Fator de Transcrição Brn-3A/metabolismo
17.
Appl Environ Microbiol ; 83(23)2017 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-28970223

RESUMO

"Daqu" is a saccharifying and fermenting agent commonly used in the traditional solid-state fermentation industry (e.g., baijiu and vinegar). The patterns of microbial community succession and flavor formation are highly similar among batches, yet the mechanisms promoting temporal succession in the Daqu microbial ecology remain unclear. Here, we first correlated temporal profiles of microbial community succession with environmental variables (temperature, moisture, and titratable acidity) in medium temperature Daqu (MT-Daqu) throughout fermentation. Temperature dynamics significantly correlated (P < 0.05) with the quick succession of MT-Daqu microbiota in the first 12 d of fermentation, while the community structure was relatively stable after 12 d. Then, we explored the effect of temperature on the MT-Daqu community assembly. In the first 4 d of fermentation, the rapid propagation of most bacterial taxa and several fungal taxa, including Candida, Wickerhamomyces, and unclassified Dipodascaceae and Saccharomycetales species, significantly increased MT-Daqu temperature to 55°C. Subsequently, sustained bio-heat generated by microbial metabolism (53 to 56°C) within MT-Daqu inhibited the growth of most microbes from day 4 to day 12, while thermotolerant taxa, including Bacillus, unclassified Streptophyta, Weissella, Thermoactinomyces, Thermoascus, and Thermomyces survived or kept on growing. Furthermore, temperature as a major driving force on the shaping of MT-Daqu microbiota was validated. Lowering the fermentation temperature by placing the MT-Daqu in a 37°C incubator resulted in decreased relative abundances of thermotolerant taxa, including Bacillus, Thermoactinomyces, and Thermoascus, in the MT-Daqu microbiota. This study revealed that bio-heat functioned as a primary endogenous driver promoting the formation of functional MT-Daqu microbiota.IMPORTANCE Humans have mastered the Daqu preparation technique of cultivating functional microbiota on starchy grains over thousands of years, and it is well known that the metabolic activity of these microbes is key to the flavor production of Chinese baijiu. The pattern of microbial community succession and flavor formation remains highly similar between batches, yet mechanistic insight into these patterns and into microbial population fidelity to specific environmental conditions remains unclear. Our study revealed that bio-heat was generated within Daqu bricks in the first 4 d of fermentation, concomitant with rapid microbial propagation and metabolism. The sustained bio-heat may then function as a major endogenous driving force promoting the formation of the MT-Daqu microbiota from day 4 to day 12. The bio-heat-driven growth of thermotolerant microorganisms might contribute to the formation of flavor metabolites. This study provides useful information for the temperature-based modulation of microbiota function during the fermentation of Daqu.


Assuntos
Bactérias/metabolismo , Microbiota , Vinho/microbiologia , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Biodiversidade , China , Grão Comestível/microbiologia , Temperatura , Vinho/análise
18.
Chin Med J (Engl) ; 129(6): 672-8, 2016 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-26960370

RESUMO

BACKGROUND: Wolf-Hirschhorn syndrome (WHS) is a contiguous gene syndrome that is typically caused by a deletion of the distal portion of the short arm of chromosome 4. However, there are few reports about the features of Chinese WHS patients. This study aimed to characterize the clinical and molecular cytogenetic features of Chinese WHS patients using the combination of multiplex ligation-dependent probe amplification (MLPA) and array comparative genomic hybridization (array CGH). METHODS: Clinical information was collected from ten patients with WHS. Genomic DNA was extracted from the peripheral blood of the patients. The deletions were analyzed by MLPA and array CGH. RESULTS: All patients exhibited the core clinical symptoms of WHS, including severe growth delay, a Greek warrior helmet facial appearance, differing degrees of intellectual disability, and epilepsy or electroencephalogram anomalies. The 4p deletions ranged from 2.62 Mb to 17.25 Mb in size and included LETM1, WHSC1, and FGFR3. CONCLUSIONS: The combined use of MLPA and array CGH is an effective and specific means to diagnose WHS and allows for the precise identification of the breakpoints and sizes of deletions. The deletion of genes in the WHS candidate region is closely correlated with the core WHS phenotype.


Assuntos
Hibridização Genômica Comparativa/métodos , Reação em Cadeia da Polimerase Multiplex/métodos , Síndrome de Wolf-Hirschhorn/genética , Criança , Pré-Escolar , Feminino , Genótipo , Humanos , Lactente , Recém-Nascido , Masculino , Fenótipo
19.
Taiwan J Obstet Gynecol ; 55(1): 104-8, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26927259

RESUMO

OBJECTIVE: We present prenatal diagnosis, genetic counseling, and molecular cytogenetic features of familial recurrence of Wolf-Hirschhorn syndrome (WHS). MATERIALS AND METHODS: A 31-year-old woman was referred to a hospital at 24 weeks of gestation because of abnormal ultrasound findings in the fetus. Her first child was a boy who had growth retardation, mental defect, and a distinctive facial appearance. Based on the conventional cytogenetic analysis, the combined use of multiplex ligation-dependent probe amplification (MLPA) and array comparative genomic hybridization (aCGH) facilitated the prenatal diagnosis and genetic counseling in the fetus. Results of the standard G-banging karyotype analysis of the fetus, the parents, and the boy were normal. RESULTS: The MLPA analysis revealed the same 4p microdeletion accompanied by 2p microduplication in the fetus and the boy. The aCGH analysis revealed a 3.57-Mb 4p16.3 microdeletion or arr [hg19] 4p16.3 (71,552-3,636,893) x1 in the fetus and a 3.29-Mb 4p16.3 microdeletion or arr [hg19] 4p16.3 (71,148-3,360,737) x1 in the boy. The 3.57-Mb 4p16.3 microdeletion encompassed 39 OMIM genes. The 3.29-Mb 4p16.3 microdeletion encompassed 36 OMIM genes. They both included LETM1 and WHSC1. The 2p25.3 microduplication was smaller than 666 kb and encompassed only one OMIM gene, ACP1. CONCLUSION: The combined use of MLPA and aCGH is an effective way to diagnose recurrent WHS. Although WHS is typically caused by a de novo deletion, prenatal diagnosis and genetic counseling are necessary in the next pregnancy in families that have suffered such cases.


Assuntos
Deleção Cromossômica , Duplicação Cromossômica , Cromossomos Humanos Par 2 , Cromossomos Humanos Par 4 , Doenças Fetais/genética , Síndrome de Wolf-Hirschhorn/genética , Aborto Eugênico , Adulto , Criança , Hibridização Genômica Comparativa , Feminino , Doenças Fetais/diagnóstico por imagem , Aconselhamento Genético , Humanos , Masculino , Reação em Cadeia da Polimerase Multiplex , Gravidez , Ultrassonografia Pré-Natal , Síndrome de Wolf-Hirschhorn/diagnóstico por imagem
20.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 34(10): 1220-4, 2014 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-25509266

RESUMO

OBJECTIVE: To study the effect of dihydroartemisinin (DHA) combined irradiation on the apoptosis of human lung cancer GLC-82 cells and to study its mechanism. METHODS: The growth inhibition rate of GLC-82 cells acted by different concentrations DHA was detected using MTT assay at 24, 48, and 72 h, respectively. Clone forming test was used. With multi-target single-hit model, the radiosensitization effect was assessed by calculating sensitizing enhancement ratio (SER).The effect of DHA combined irradiation on the apoptosis of GLC-82 cell cycle distribution and apoptosis were measured by flow cytometry. The protein expression of p53, p21, Bcl-2, and Bax were detected by Western blot. RESULTS: Different concentrations DHA (4, 8, 16, 32, 64, and 128 µg/mL) had cytotoxicity on GLC-82 cells. The IC50 for 24, 48, and 72 h was 38.25,20.58, and 10.36 µg/mL, respectively, in obvious dose- and time-dependent manner. The growth inhibition rate was more significantly increased than that of the blank control group (P < 0.01, P<0.05). DHA had sensitization enhancement effect on GLC-82 cells, with SER of 1.4. DHA combined irradiation could obviously change the structure of GLC-82 cells cell cycle and induce apoptosis (with the apoptosis rate of 21.5%), which was significantly different from that of the blank control group (P < 0.05). Western blot showed the expression of p53 and p21 protein could be increased by DHA combined irradiation, and the expression of Bcl-2 protein down-regulated (P <0.01, P <0. 05). CONCLUSIONS: DHA had stronger cytotoxicity and radiosensitization on GLC-82 cells. Its mechanisms might lie in making the arrest of GLC-82 cells' growth at G0/G1 phase, decreasing the ratio of cells at S phase, restoring the function of p53, decreasing the expression of Bcl-2 protein, and inducing apoptosis in GLC-82 cells.


Assuntos
Apoptose/efeitos dos fármacos , Artemisininas/farmacologia , Neoplasias Pulmonares/metabolismo , Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Citometria de Fluxo , Humanos , Proteínas de Neoplasias/metabolismo , Radiossensibilizantes/farmacologia , Células Tumorais Cultivadas , Proteína X Associada a bcl-2/metabolismo
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