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1.
Environ Res ; 251(Pt 2): 118747, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38527717

RESUMO

A composite material, cow dung-doped sludge biochar (Zn@SBC-CD), was synthesized by one-step pyrolysis using ZnCl2 as an activating agent and applied to a catalytic ozonation process (COP) for methylene blue (MB) removal. SEM, XRD, FTIR, XPS and BET analyses were performed to characterize the biochar (BC) catalysts. Zn@SBC-CD had high graphitization degree, abundant active sites and uniform distribution of Zn on its surface. Complete removal of MB was achieved within 10 min, with a removal rate much higher than that of ozone alone (32.4%), implying the excellent ozone activation performance of Zn@SBC-CD. The influence of experimental parameters on MB removal efficiency was examined. Under the optimum conditions in terms of ozone dose 0.04 mg/mL, catalyst dose 400 mg/L and pH 6.0, COD was completely removed after 20 min. Electron paramagnetic resonance (EPR) analysis revealed radical and non-radical pathways were involved in MB degradation. The Zn@SBC-CD/O3 system generated superoxide anion radicals (•O2-), which were the main active species for MB removal, through adsorption, transformation, and transfer, Furthermore, Zn@SBC-CD exhibited good reusability and stability in cycling experiments. This study provides a novel approach for the utilization of cow dung and sludge in synthesis of functional biocatalysts and application in organic wastewater treatment.


Assuntos
Carvão Vegetal , Grafite , Ozônio , Ozônio/química , Carvão Vegetal/química , Animais , Bovinos , Catálise , Grafite/química , Esgotos/química , Azul de Metileno/química , Radicais Livres/química , Poluentes Químicos da Água/química , Esterco/análise
2.
Environ Technol ; : 1-10, 2023 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-37534577

RESUMO

ABSTRACTThe distribution and removal pathways of heavy metals within different sludge treatment wetlands (STWs) during different running periods in Northeast China have not been well studied. In this study, we examined three STWs, i.e. an STW with aeration tubes only (unit 1; U1), an STW with reeds and aeration tubes (unit 2; U2), and an STW with reeds only (unit 3; U3). The results showed that the levels of Cu as well as Zn accumulated faster within STW residual sludge, whereas the levels of Cd, Cr, Ni, and Pb accumulated more slowly and decreased slightly over time. The removal rates of heavy metals from the influent sludge by STWs ranged from 64.5% (Cr) to 92.2% (Zn). Reeds removed heavy metals from the STWs by direct absorption, and Zn was highly enriched in the reeds. The presence of reeds also promoted the spreading of heavy metals to the substrate layer and improved the removal of heavy metals in STWs. The mass of each heavy metal accumulated within the residual sludge of U2 and U3 was lower than that of U1, indicating that reeds could facilitate the removal of heavy metals. The STWs removed heavy metal mainly by substrate adsorption, and the mass percentage of heavy metals accumulated in the substrate ranged from 35.8 to 63.6%.

3.
Biotechnol Biofuels Bioprod ; 15(1): 24, 2022 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-35246204

RESUMO

BACKGROUND: D-Lactic acid played an important role in the establishment of PLA as a substitute for petrochemical plastics. But, so far, the D-lactic acid production was limited in only pilot scale, which was definitely unable to meet the fast growing market demand. To achieve industrial scale D-lactic acid production, the cost-associated problems such as high-cost feedstock, expensive nutrient sources and fermentation technology need to be resolved to establish an economical fermentation process. RESULTS: In the present study, the combined effect of B vitamin supplementation and membrane integrated continuous fermentation on D-lactic acid production from agricultural lignocellulosic biomass by Lactobacillus delbrueckii was investigated. The results indicated the specific addition of vitamins B1, B2, B3 and B5 (VB1, VB2, VB3 and VB5) could reduce the yeast extract (YE) addition from 10 to 3 g/l without obvious influence on fermentation efficiency. By employing cell recycling system in 350 h continuous fermentation with B vitamin supplementation, YE addition was further reduced to 0.5 g/l, which resulted in nutrient source cost reduction of 86%. A maximum D-lactate productivity of 18.56 g/l/h and optical purity of 99.5% were achieved and higher than most recent reports. CONCLUSION: These findings suggested the novel fermentation strategy proposed could effectively reduce the production cost and improve fermentation efficiency, thus exhibiting great potential in promoting industrial scale D-lactic acid production from lignocellulosic biomass.

4.
Sci Total Environ ; 790: 148199, 2021 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-34111785

RESUMO

Dairy manure (DM) is a kind of cheap cellulosic biomass resource which includes lignocellulose and mineral nutrients. Random stacks not only leads damage to the environment, but also results in waste of natural resources. The traditional ways to use DM include returning it to the soil or acting as a fertilizer, which could reduce environmental pollution to some extent. However, the resource utilization rate is not high and socio-economic performance is not utilized. To expand the application of DM, more and more attention has been paid to explore its potential as bioenergy or bio-chemicals production. This article presented a comprehensive review of different types of bioenergy production from DM and provided a general overview for bioenergy production. Importantly, this paper discussed potentials of DM as candidate feedstocks not only for biogas, bioethanol, biohydrogen, microbial fuel cell, lactic acid, and fumaric acid production by microbial technology, but also for bio-oil and biochar production through apyrolysis process. Additionally, the use of manure for replacing freshwater or nutrients for algae cultivation and cellulase production were also discussed. Overall, DM could be a novel suitable material for future biorefinery. Importantly, considerable efforts and further extensive research on overcoming technical bottlenecks like pretreatment, the effective release of fermentable sugars, the absence of robust organisms for fermentation, energy balance, and life cycle assessment should be needed to develop a comprehensive biorefinery model.


Assuntos
Biocombustíveis , Esterco , Biomassa , Fermentação , Tecnologia
5.
Enzyme Microb Technol ; 126: 62-68, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31000165

RESUMO

The effects of divalent copper (Cu(II)) on microbial community, enzymatic activity and functional genes in a sequencing batch reactor (SBR) at tetracycline (TC) stress were investigated. The enzymatic activity and functional genes abundance associated with nitrification and denitrification at a 20 mg L-1 TC stress were higher than those at a mixtures stress of 20 mg L-1 TC and 10 mg L-1 Cu(II), while they were lower than those at a mixtures stress of 20 mg L-1 TC and 40 mg L-1 Cu(II). Compared to lactate dehydrogenase (LDH) release and reactive oxygen species (ROS) production at a 20 mg L-1 TC stress, they were lower at the TC stress with 10 mg L-1 Cu(II), while they were higher at the TC stress with 40 mg L-1 Cu(II). The incremental Cu(II) concentration at a 20 mg L-1 TC stress could not change the result that the sensitivity of denitrifying enzymatic activity to TC was higher than nitrifying enzymatic activity. Compared to the relative abundance of nitrifers and denitrifers at a 20 mg L-1 TC stress, the 10 mg L-1 Cu(II) addition resulted in their increase, while they decreased as the 40 mg L-1 Cu(II) addition. The relative abundance of genera Pseudomonas, Rivibacter and Nitrobacter at the stress of Cu(II) and TC were higher than those at TC stress, suggested they had an ability to resist the stress of Cu(II) and TC.


Assuntos
Cobre/farmacologia , Desnitrificação , Genes Bacterianos , L-Lactato Desidrogenase/metabolismo , Microbiota , Nitrificação , Tetraciclinas/toxicidade , Espécies Reativas de Oxigênio/metabolismo , Eliminação de Resíduos Líquidos
6.
Bioresour Technol ; 249: 916-923, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29145118

RESUMO

The long-term effects of combined divalent copper (Cu(II)) and tetracycline (TC) on the performance, microbial activity and community in a sequencing batch reactor (SBR) were investigated. The addition of Cu(II), TC or mixed Cu(II)/TC caused the decrease of the organics and nitrogen removal efficiencies, and their decreased degrees were the lowest at the addition of mixed Cu(II)/TC. The increase of mixed Cu(II)/TC concentrations in the influent did not change the antagonistic effects between Cu(II) and TC on nitrifying and denitrifying activities. Nitrifiers had higher tolerances to Cu(II), TC and mixed Cu(II)/TC than denitrifiers. Compared to the addition of Cu(II) or TC alone, the microbial community richness was higher at the addition of mixed Cu(II)/TC, while the microbial community diversity was lower. The increased protein (PN) in extracellular polymeric substances (EPS) was a protective response of bacteria to Cu(II), TC and mixed Cu(II)/TC.


Assuntos
Reatores Biológicos , Cobre , Tetraciclina , Nitrogênio , Tempo
7.
Biotechnol Biofuels ; 10: 236, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29046722

RESUMO

BACKGROUND: Environmental issues, such as the fossil energy crisis, have resulted in increased public attention to use bioethanol as an alternative renewable energy. For ethanol production, water and nutrient consumption has become increasingly important factors being considered by the bioethanol industry as reducing the consumption of these resources would decrease the overall cost of ethanol production. Biogas slurry contains not only large amounts of wastewater, but also the nutrients required for microbial growth, e.g., nitrogen, ammonia, phosphate, and potassium. Therefore, biogas slurry is an attractive potential resource for bioethanol production that could serve as an alternative to process water and nitrogen sources. RESULTS: In this study, we propose a method that replaces the process water and nitrogen sources needed for cellulosic ethanol production by Zymomonas mobilis with biogas slurry. To test the efficacy of these methods, corn straw degradation following pretreatment with diluted NaOH and enzymatic hydrolysis in the absence of fresh water was evaluated. Then, ethanol fermentation using the ethanologenic bacterial strain Z. mobilis ZMT2 was conducted without supplementing with additional nitrogen sources. After pretreatment with 1.34% NaOH (w/v) diluted in 100% biogas slurry and continuous enzymatic hydrolysis for 144 h, 29.19 g/L glucose and 12.76 g/L xylose were generated from 30 g dry corn straw. The maximum ethanol concentration acquired was 13.75 g/L, which was a yield of 72.63% ethanol from the hydrolysate medium. Nearly 94.87% of the ammonia nitrogen was depleted and no nitrate nitrogen remained after ethanol fermentation. The use of biogas slurry as an alternative to process water and nitrogen sources may decrease the cost of cellulosic ethanol production by 10.0-20.0%. By combining pretreatment with NaOH diluted in biogas slurry, enzymatic hydrolysis, and ethanol fermentation, 56.3 kg of ethanol was produced by Z. mobilis ZMT-2 through fermentation of 1000 kg of dried corn straw. CONCLUSIONS: In this study, biogas slurry replaced process water and nitrogen sources during cellulosic ethanol production. The results suggest that biogas slurry is a potential alternative to water when pretreating corn straw and, thus, has important potential applications in cellulosic ethanol production from corn straw. This study not only provides a novel method for utilizing biogas slurry, but also demonstrates a means of reducing the overall cost of cellulosic ethanol.

8.
Int J Syst Evol Microbiol ; 67(4): 772-777, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27902214

RESUMO

Two novel aerobic bacteria, designated strains LAM0312T and LAM0313, were isolated from saline soil samples collected from a paddy field in Dezhou city, Shandong Province, China. Cells of these strains were Gram-stain-positive, sporogenous, rod-shaped and motile with peritrichous flagella. The optimal growth temperature and pH were 30 °C and pH 7.0-8.0. Strain LAM0312T was able to grow in the presence of 12 % (w/v) NaCl. The major fatty acids were anteiso-C15 : 0 and iso-C15 : 0. The dominant polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, glycolipids, five unidentitied lipids and phosphatidylmonomethylethanolamine. The cell-wall peptidoglycan was found to contain meso-diaminopimelic acid. The predominant menaquinone was identified as menaquinone-7. The G+C content of the genomic DNA of strains LAM0312T and LAM0313 was 45.0 and 46.0 mol%, respectively, as determined by the Tm method. 16S rRNA gene sequence similarity analysis indicated that the strains were closely related to Brevibacillus laterosporus DSM 25T and Brevibacillus fluminis JCM 15716T with 98.5 and 96.4 % sequence similarity, respectively. The DNA-DNA hybridization value between strain LAM0312T and LAM0313 was 92±0.6 % (reciprocal 90±0.2 %) and the value between strain LAM0312T and Brevibacillus laterosporus DSM 25T was 48±0.5 % (reciprocal 40±0.4 %). On the basis of the phenotypic, phylogenetic and chemotaxonomic characteristics, the two strains are proposed to represent a novel species of the genus Brevibacillus, for which the name Brevibacillus halotolerans sp. nov. is proposed. The type strain is LAM0312T (=ACCC 06527T=JCM 30849T).


Assuntos
Brevibacillus/classificação , Filogenia , Microbiologia do Solo , Técnicas de Tipagem Bacteriana , Composição de Bases , Brevibacillus/genética , Brevibacillus/isolamento & purificação , China , DNA Bacteriano/genética , Ácido Diaminopimélico/química , Ácidos Graxos/química , Glicolipídeos/química , Hibridização de Ácido Nucleico , Oryza , Peptidoglicano/química , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Salinidade , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
9.
Int J Syst Evol Microbiol ; 67(4): 806-811, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27902257

RESUMO

A Gram-stain-negative, non-spore-forming, non-motile and aerobic coccobacilli-shaped strain, designated BRTC-1T, was isolated from the gut of Omphisa fuscidentalis Hampson, which is a larva of a moth and was collected from Xishuangbanna Dai Autonomous Prefecture in China. The isolate was found to grow at NaCl concentrations of 0-5 % (w/v) (optimum: 0 %), 10-45 °C (optimum: 30-35 °C) and pH 5.0-9.0 (optimum: pH 6.0) on tryptic soy agar. Analysis of the 16S rRNA gene sequence indicated that the isolate belonged to the genus Acinetobacter and was most closely related to Acinetobacter rudis LMG 26107T, Acinetobacter guillouiae LMG 988T and Acinetobacter bereziniae LMG 1003T with 96.4, 96.3 and 96.3 % sequence similarity, respectively. The comparative sequence analyses of the rpoB and gyrB genes showed that BRTC-1T is distant from the species of the genus Acinetobacter with validly published names (≤84.0 and ≤82.0 % similarity, respectively). The average nucleotide identity and digital DNA-DNA hybridization values (≤77.0 and ≤22.8 %, respectively) between the whole-genome sequence of BRTC-1T and those of the known taxa were far below the thresholds used to discriminate bacterial species. The major fatty acids were determined to be C16 : 0, C18 : 1ω9c and C16 : 1ω7c/iso-C15 : 0 2-OH. The respiratory quinone was Q-9. The polar lipids were found to be diphosphatidyglycerol, phosphatidylglycerol, phosphatidylethanolamine, five phospholipids and one phosphatidylcholine. Based on its phenotypic and chemotaxonomic characteristics from this study, the isolate is concluded to represent a novel species of the genus Acinetobacter, for which the name Acinetobacter larvae sp. nov. is proposed. The type strain is BRTC-1T (=ACCC 19936T=JCM 31367T).


Assuntos
Acinetobacter/classificação , Mariposas/microbiologia , Filogenia , Acinetobacter/genética , Acinetobacter/isolamento & purificação , Animais , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Genes Bacterianos , Larva/microbiologia , Hibridização de Ácido Nucleico , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
10.
Bioresour Technol ; 219: 114-122, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27479802

RESUMO

A thermophilic strain Bacillus coagulans (NBRC 12714) was employed to produce l-lactic acid from corn stover hydrolysate in membrane integrated continuous fermentation. The strain NBRC 12714 metabolized glucose and xylose by the Embden-Meyerhof-Parnas pathway (EMP) and the pentose phosphate pathway (PPP), producing l-lactic acid with optical purity >99.5%. The overall l-lactic acid titer of 92g/l with a yield of 0.91g/g and a productivity of 13.8g/l/h were achieved at a dilution rate of 0.15h(-1). The productivity obtained was 1.6-fold than that of conventional continuous fermentation without cell recycling, and also was the highest among the relevant studies ever reported. These results indicated that the process developed had great potential for economical industrial production of l-lactic acid from lignocellulosic biomass.


Assuntos
Bacillus coagulans/metabolismo , Glucose/metabolismo , Glicólise , Ácido Láctico/biossíntese , Via de Pentose Fosfato , Xilose/metabolismo , Biomassa , Zea mays
11.
Microb Cell Fact ; 15(1): 101, 2016 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-27287016

RESUMO

BACKGROUND: The cell growth and ethanol yield of Zymomonas mobilis may be detrimentally affected by salt stress frequently present in some biomass-based fermentation systems, leading to a decrease in the rate of sugar conversion to ethanol or other bioproducts. To address this problem, improving the salt tolerance of Z. mobilis is a desirable way. However, limited progress has been made in development of Z. mobilis with higher salt tolerance for some technical challenges in the past decades. Recently, transposon insertion mutant system has been widely used as a novel genetic tool in many organisms to develop mutant strains. In this study, Tn5-based transposon insertion mutagenesis system firstly used for construction of higher salt tolerance strain in Z. mobilis. RESULTS: Approximately 200 Z. mobilis ZM4 mutants were generated by using Tn5-based transposon mutagenesis system. The mutant strain ZMT2 with improved salt tolerance phenotype was obtained by screening on RM agar plates with additional 1 % NaCl. Strain ZMT2 was confirmed to exhibit better fermentation performance under NaCl stress than wild type of strain ZM4. The transposon insertion was located in ZMO1122 (himA) by genome walking. Discruption of himA gene showed that himA may play an important role in response to salt tolerance in Z. mobils. CONCLUSIONS: The mutant strain ZMT2 with a transposon insertion in himA gene of the genome showed obviously higher sugar conversion rate to ethonal under up to 2 % NaCl stress than did the wild ZM4 strain. Besides, ZMT2 exhibited shared fermentative capabilities with wild ZM4 strain under no or low NaCl stress. This report firstly showed that himA played a role in responding to NaCl stress. Furthermore, the result indicated that Tn5-based transposon mutagenesis system was a feasible tool not only for genetic engineering in Z. mobilis strain improvement, but also in tapping resistent genes.


Assuntos
Tolerância ao Sal/genética , Transposases/genética , Zymomonas/genética , Zymomonas/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Etanol/metabolismo , Engenharia Genética , Glucose/metabolismo , Mutagênese Insercional , NAD/metabolismo , Fenótipo , Reação em Cadeia da Polimerase em Tempo Real , Transposases/metabolismo , Zymomonas/crescimento & desenvolvimento
12.
Arch Microbiol ; 198(6): 559-64, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27055557

RESUMO

A novel aerobic, Gram-stain-positive, sporogenous, rod-shaped bacterium, designated LAM0415(T), was isolated from an alcohol fermentation pit mud sample collected from Sichuan Luzhou-flavour liquor enterprise in China. The isolate was found to be able to grow at NaCl concentrations of 0-10 % (w/v) (optimum: 1.0 %), 10-50 °C (optimum: 30-35 °C) and pH 3.0-10.0 (optimum: 7.0-8.0). Phylogenetic analysis of 16S rRNA gene sequences indicated that the new isolate belonged to the genus Bacillus and was closely related to Bacillus sporothermodurans DSM 10599(T) and Bacillus oleronius DSM 9356(T), with 98.4 and 97.2 % sequence similarity, respectively. The DNA-DNA hybridization values between strain LAM0415(T) and the two reference strains were 33.3 ± 1.2 and 42.8 ± 0.8 %, respectively. The genomic DNA G+C content was 35.2 mol% as determined by the T m method. The major fatty acids were determined to be iso-C15:0, anteiso-C15:0 and anteiso-C17:0. The predominant menaquinones were identified as MK7 and MK8. The major polar lipids were found to be diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, one unidentified phospholipid and four unidentified glycolipids. The diagnostic amino acid of the cell wall peptidoglycan was determined to be meso-diaminopimelic acid. On the basis of its phenotypic, phylogenetic and chemotaxonomic characteristics, strain LAM0415(T) (=ACCC 06413(T) = JCM 19841(T)) represents the type strain of a novel species of the genus Bacillus, for which the name Bacillus vini sp. nov. is proposed.


Assuntos
Álcoois/metabolismo , Bacillus , Microbiologia do Solo , Bacillus/classificação , Bacillus/genética , Bacillus/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , Parede Celular/metabolismo , China , DNA Bacteriano/genética , Ácido Diaminopimélico/análise , Ácidos Graxos/análise , Fermentação , Glicolipídeos/análise , Hibridização de Ácido Nucleico , Peptidoglicano/química , Fosfatidiletanolaminas/análise , Fosfolipídeos/análise , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Cloreto de Sódio/metabolismo
13.
Bioresour Technol ; 205: 213-21, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26829529

RESUMO

The differences between biofilm and suspended sludge (S-sludge) in extracellular polymeric substances (EPS), microbial activity, and microbial community in an anoxic-aerobic sequencing batch biofilm reactor (SBBR) at different concentrations of divalent cadmium (Cd(II)) were investigated. As the increase of Cd(II) concentration from 0 to 50mgL(-1), the specific ammonium oxidation rate (SAOR), specific nitrite oxidation rate (SNOR), and specific nitrate reduction rate (SNRR) of biofilm decreased from 4.85, 5.22 and 45mgNg(-1) VSSh(-1) to 1.54, 2.38 and 26mgNg(-1)VSSh(-1), respectively, and the SAOR, SNOR and SNRR of S-sludge decreased from 4.80, 5.02 and 34mgNg(-1)VSSh(-1) to 1.46, 2.20 and 17mgNg(-1)VSSh(-1), respectively. Biofilm had higher protein (PN) content in EPS than S-sludge. Contrast to S-sludge, biofilm could provide Nitrobacter vulgaris, beta proteobacterium INBAF015, and Pseudoxanthomonas mexicana with the favorable conditions of growth and reproduction.


Assuntos
Biofilmes/efeitos dos fármacos , Reatores Biológicos/microbiologia , Cádmio/toxicidade , Consórcios Microbianos/fisiologia , Eliminação de Resíduos Líquidos/métodos , Biofilmes/crescimento & desenvolvimento , Consórcios Microbianos/efeitos dos fármacos , Nitratos/química , Nitratos/metabolismo , Nitritos/metabolismo , Nitrogênio/metabolismo , Oxirredução , Polissacarídeos/metabolismo , Esgotos/microbiologia , Eliminação de Resíduos Líquidos/instrumentação , Poluentes Químicos da Água/toxicidade
14.
Bioresour Technol ; 203: 295-302, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26744803

RESUMO

The aim of present study was to develop a process for open ethanol fermentation from food waste using an acid-tolerant mutant of Zymomonas mobilis (ZMA7-2). The mutant showed strong tolerance to acid condition of food waste hydrolysate and high ethanol production performance. By optimizing fermentation parameters, ethanol fermentation with initial glucose concentration of 200 g/L, pH value around 4.0, inoculum size of 10% and without nutrient addition was considered as best conditions. Moreover, the potential of bench scales fermentation and cell reusability was also examined. The fermentation in bench scales (44 h) was faster than flask scale (48 h), and the maximum ethanol concentration and ethanol yield (99.78 g/L, 0.50 g/g) higher than that of flask scale (98.31 g/L, 0.49 g/g). In addition, the stable cell growth and ethanol production profile in five cycles successive fermentation was observed, indicating the mutant was suitable for industrial ethanol production.


Assuntos
Etanol/metabolismo , Alimentos , Eliminação de Resíduos/métodos , Zymomonas/metabolismo , Conservação de Recursos Energéticos/métodos , Fermentação , Glucose/metabolismo , Zymomonas/genética
15.
J Biotechnol ; 220: 88-9, 2016 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-26806488

RESUMO

The type strain Lentibacillus amyloliquefaciens LAM0015(T) with considerably highly NaCl tolerance is a member of halophiles. Here we report its genome sequence, the first to publish complete genome sequence of the Lentibacillus genus. It contains 3,858,520bp with an average GC content of 42.12%, encoding multiple valuable proteins academically and industrially. The genome sequence of strain LAM0015(T) provides basic information for further elucidation of halophilic mechanism and wider exploitation of functional genes.


Assuntos
Bacillaceae/genética , Genoma Bacteriano , Bacillaceae/isolamento & purificação , Bacillaceae/fisiologia , Composição de Bases , Sequência de Bases , China , Mapeamento Cromossômico , DNA Bacteriano/genética , Tamanho do Genoma , Microbiologia Industrial , Dados de Sequência Molecular , RNA Bacteriano/genética , Cloreto de Sódio , Microbiologia do Solo
16.
Antonie Van Leeuwenhoek ; 109(2): 171-8, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26545789

RESUMO

A Gram-stain positive, non-motile, non-sporogenous, aerobic, rod-shaped and halophilic bacterium, designated LAM0015(T), was isolated from a saline sediment sample collected from Yantai City in China. The isolate was found to be able to grow at NaCl concentrations of 5-25 % (w/v) (optimum: 7-12 %), 15-45 °C (optimum: 35 °C) and pH 5.0-9.0 (optimum: 7.0). The major fatty acids were determined to be anteiso-C15:0 and anteiso-C17:0. The predominant respiratory quinone was identified as MK-7. The cell wall peptidoglycan was determined to contain meso-diaminopimelic acid. The polar lipids were found to be diphosphatidyglycerol, phosphatidylglycerol, five phospholipids and one glycolipid. The DNA G+C content was 43.1 mol% as determined by the T m method. Analysis of the 16S rRNA gene sequence indicated that the isolate belongs within the genus Lentibacillus and is closely related to Lentibacillus persicus DSM 22530(T), Lentibacillus salicampi JCM 11462(T) and Lentibacillus jeotgali JCM 15795(T) with 97.3, 96.7 and 96.4 % sequence similarity, respectively. The DNA-DNA hybridization value between LAM0015(T) and L. persicus DSM 22530(T) was 51.2 ± 1.4 %. Based on its phenotypic, phylogenetic and chemotaxonomic characteristics, strain LAM0015(T) is concluded to represent a novel species of the genus Lentibacillus, for which the name Lentibacillus amyloliquefaciens sp. nov. is proposed. The type strain is LAM0015(T) (=ACCC 06401(T) = JCM 19838(T)).


Assuntos
Bacillaceae/isolamento & purificação , Sedimentos Geológicos/microbiologia , Cloreto de Sódio/metabolismo , Bacillaceae/classificação , Bacillaceae/genética , Bacillaceae/metabolismo , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Ácidos Graxos/metabolismo , Sedimentos Geológicos/análise , Dados de Sequência Molecular , Filogenia , RNA Ribossômico 16S/genética , Cloreto de Sódio/análise
17.
Int J Syst Evol Microbiol ; 65(10): 3522-3526, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26297478

RESUMO

A Gram-staining-positive, spore-forming, strictly anaerobic bacterium, designated strain LAM0A37T, was isolated from enrichment samples collected from a petroleum reservoir in Shengli oilfield. Cells of strain LAM0A37T were rod-shaped and motile by peritrichous flagella. The optimal temperature and pH for growth were 40 °C and 7.0­7.5, respectively. The strain did not require NaCl for growth but tolerated up to 3 % (w/v) NaCl. Strain LAM0A37T was able to utilize glucose, fructose, maltose, xylose, sorbitol, cellobiose, melibiose and melezitose as sole carbon sources. Sulfite was used as an electron acceptor. The main products of glucose fermentation were acetate and CO2. The predominant fatty acid was C16 : 0 (23.6 %). The main polar lipid profile comprised of five glycolipids, six phospholipids and two lipids. No menaquinone was detected. The genomic DNA G+C content was 27.1 ± 0.2 mol% as determined by the T m method. Analysis of the 16S rRNA gene sequence indicated that the isolate was a member of the genus Terrisporobacter, and was most closely related to Terrisporobacter glycolicus JCM 1401T and Terrisporobacter mayombei DSM 6539T with 98.3 % 16S rRNA gene sequence similarity to both. DNA­DNA hybridization values between strain LAM0A37T and type strains of Terrisporobacter glycolicus and Terrisporobacter mayombei were 45.6 ± 0.3 % and 38.3 ± 0.4 %, respectively. Based on phenotypic, phylogenetic and chemotaxonomic characteristics, strain LAM0A37T is suggested to represent a novel species of the genus Terrisporobacter, for which the name Terrisporobacter petrolearius sp. nov. is proposed. The type strain is LAM0A37T ( = ACCC 00740T = JCM 19845T).


Assuntos
Clostridiales/classificação , Campos de Petróleo e Gás/microbiologia , Petróleo/microbiologia , Filogenia , Técnicas de Tipagem Bacteriana , Composição de Bases , China , Clostridiales/genética , Clostridiales/isolamento & purificação , DNA Bacteriano/genética , Ácidos Graxos/química , Glicolipídeos/química , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/química
18.
Int J Syst Evol Microbiol ; 65(9): 2797-2802, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25991663

RESUMO

A novel aerobic, Gram-staining-negative bacterium, designated strain LAM-WHM-ZC(T), was isolated from coastal sediment samples from the Bohai Sea, near Yantai, China. Cells of LAM-WHM-ZC(T) were non-motile, short-rod- or coccoid-shaped. The temperature and pH ranges for growth were 4-40 °C (optimum: 20-33 °C) and pH 5-9 (optimum: pH 7.5). The strain did not require NaCl for growth but tolerated up to 10% NaCl (w/v). The major fatty acids of strain LAM-WHM-ZC(T) were summed feature 3, C12 : 0, C16 : 0, summed feature 2 and summed feature 8. The predominant respiratory quinone was ubiquinone Q-8. The main polar lipids were diphosphatidyglycerol, phosphatigylethanolamine, phosphatidyglycerol, one phospholipid and four unidentified glycolipids. The DNA G+C content was 59.3 mol% as determined by the melting temperature (Tm) method. Analysis of the 16S rRNA gene sequence indicated that the isolate represented a member of the genus Oceanisphaera and was closely related to Oceanisphaera arctica KCTC 23013(T), Oceanisphaera litoralis DSM 15406(T), Oceanisphaera sediminis KACC 15117(T) and Oceanisphaera donghaensis KCTC 12522(T) with 97.7%, 97.1%, 96.6% and 96.6% sequence similarity, respectively. The DNA-DNA hybridization values between strain LAM-WHM-ZC(T) and the four reference strains were 47.4 ± 2.8%, 33.5 ± 2.2%, 28.4 ± 1.8% and 13.7 ± 0.8%, respectively. Based on its phenotypic and genotypic properties, strain LAM-WHM-ZC(T) is suggested to represent a novel species of the genus Oceanisphaera, for which the name Oceanisphaera psychrotolerans sp. nov. is proposed. The type strain is LAM-WHM-ZC(T) ( = ACCC 06516(T) = JCM 30466(T)).


Assuntos
Aeromonadaceae/classificação , Sedimentos Geológicos/microbiologia , Filogenia , Aeromonadaceae/genética , Aeromonadaceae/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Glicolipídeos/química , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Água do Mar/microbiologia , Análise de Sequência de DNA , Temperatura , Ubiquinona/química
19.
Antonie Van Leeuwenhoek ; 107(6): 1429-36, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25896305

RESUMO

A novel facultatively anaerobic bacterial strain, designated LAM0504(T), was isolated from a pit mud of Luzhou flavour liquor alcohol fermentation in Sichuan Province, China. Cells of strain LAM0504(T) were observed to be Gram-stain negative, spore-forming, rod shaped and motile by means of peritrichous flagella. Strain LAM0504(T) was found to be able to grow at 20-48 °C (optimum: 30 °C), pH 5.0-9.0 (optimum: 7.0) and 0-3 % NaCl (w/v) (optimum: 1.0 %). The 16S rRNA gene sequence similarity analysis showed that strain LAM0504(T) was most closely related to Paenibacillus konsisdensis JCM 14798(T), Fontibacillus phaseoli LMG 27589(T) and Paenibacillus motobuensis JCM 12774(T), with 97.0, 96.8 and 96.7 % sequence similarity, respectively. The DNA-DNA hybridization value between strain LAM0504(T) and P. konsisdensis JCM 14798(T) was 53.3 ± 1.2 %. The genomic DNA G+C content of strain LAM0504(T) was 43.0 mol% as determined by the Tm method. The major fatty acids of strain LAM0504(T) were identified as anteiso-C15:0, C16:0 and iso-C15:0. The cell-wall peptidoglycan was found to contain meso-diaminopimelic acid. The predominant menaquinone was identified as MK-7. The major polar lipids were found to be diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, two unidentified phospholipids, two unidentified glycolipids and three unidentified lipids. On the basis of its physiological and phylogenetic characteristics, strain LAM0504(T) is concluded to represent a novel species of the genus Paenibacillus, for which the name Paenibacillus vini sp. nov. is proposed. The type strain is LAM0504(T) (=ACCC 06420(T) = JCM 19842(T)).


Assuntos
Microbiologia de Alimentos , Paenibacillus/classificação , Paenibacillus/isolamento & purificação , Aerobiose , Álcoois/metabolismo , Anaerobiose , Técnicas de Tipagem Bacteriana , Composição de Bases , Parede Celular/química , China , Análise por Conglomerados , Citosol/química , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Ácido Diaminopimélico/análise , Ácidos Graxos/análise , Fermentação , Glicolipídeos/análise , Concentração de Íons de Hidrogênio , Locomoção , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , Paenibacillus/genética , Paenibacillus/fisiologia , Peptidoglicano/análise , Fosfolipídeos/análise , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Cloreto de Sódio/metabolismo , Temperatura , Vitamina K 2/análise
20.
Bioresour Technol ; 175: 586-93, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25459871

RESUMO

Aiming at improving the efficiency of transferring corn stover into sugars, an efficient lignocellulolytic enzyme system was developed and investigated by co-cultivation of the Coprinus comatus with Trichoderma reesei in a single bioreactor. The results showed that the lignocellulolytic enzyme activities of the co-culture exceeded that of the monoculture, suggesting synergistic interaction between two fungi. The highest laccase activity from the co-culture was 2.6-fold increase over that of the C. comatus monoculture and reached a peak 3days earlier. The maximum delignification obtained was 66.5% and about 82% of the original polysaccharides were converted into fermentable sugars by simultaneous bio-delignification and saccharification process. Correlation analysis showed that sugar yields were directly proportional to the lignin degradation. Our results suggested that co-fungi cultivation was a valuable technique for corn stover bioconversion, which could produce high efficiency of lignocellulolytic enzyme system as a cheaper alternative to commercial enzymes for industrial utilization.


Assuntos
Biotecnologia/métodos , Coprinus/enzimologia , Enzimas/metabolismo , Lignina/metabolismo , Trichoderma/enzimologia , Zea mays/metabolismo , Reatores Biológicos/microbiologia , Biotecnologia/instrumentação , Carboidratos/biossíntese , Técnicas de Cocultura , Coprinus/citologia , Enzimas/química , Lacase/metabolismo , Brotos de Planta/química , Brotos de Planta/metabolismo , Polissacarídeos/metabolismo , Trichoderma/citologia , Zea mays/química
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