共查询到20条相似文献,搜索用时 15 毫秒
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Jenni J. Seppälä Jaakko A. PuhakkaOlli Yli-Harja Matti T. KarpVille Santala 《International Journal of Hydrogen Energy》2011,36(17):10701-10708
The effect of coculture of Clostridium butyricum and Escherichia coli on hydrogen production was investigated. C. butyricum and E. coli were grown separately and together as batch cultures. Gas production, growth, volatile fatty acid production and glucose degradation were monitored. Whilst C. butyricum alone produced 2.09 mol-H2/mol-glucose the coculture produced 1.65 mol-H2/mol-glucose. However, the coculture utilized glucose more efficiently in the batch culture, i.e., it was able to produce more H2 (5.85 mmol H2) in the same cultivation setting than C. butyricum (4.62 mmol H2), before the growth limiting pH was reached. 相似文献
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Immobilized Clostridium butyricum TISTR 1032 on sugarcane bagasse improved hydrogen production rate (HPR) approximately 1.2 times in comparison to free cells. The optimum conditions for hydrogen production by immobilized C. butyricum were initial pH 6.5 and initial sucrose concentration of 25 g COD/L. The maximum HPR and hydrogen yield (HY) of 3.11 L H2/L substrate·d and 1.34 mol H2/mol hexose consumed, respectively, were obtained. Results from repeated batch fermentation indicated that the highest HPR of 3.5 L H2/L substrate·d and the highest HY of 1.52 mol H2/mol hexose consumed were obtained at the medium replacement ratio of 75% and 50% respectively. The major soluble metabolites in both batch and repeated batch fermentation were butyric and acetic acids. 相似文献
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Chien-Hung Liu Chin-Yen Chang Chieh-Lun Cheng Duu-Jong Lee Jo-Shu Chang 《International Journal of Hydrogen Energy》2012
In this work, a carbohydrate-rich microalga, Chlorella vulgaris ESP6, was grown photoautotrophically to fix the CO2. The resulting microalgal biomass was hydrolyzed by acid or alkaline/enzymatic treatment and was then used for biohydrogen production with Clostridium butyricum CGS5. The C. vulgaris biomass could be effectively hydrolyzed by acid pretreatment while similar hydrolysis efficiency was achieved by combination of alkaline pretreatment and enzymatic hydrolysis. The biomass of C. vulgaris ESP6 containing a carbohydrate content of 57% (dry weight basis) was efficiently hydrolyzed by acid treatment with 1.5% HCl, giving a reducing sugars (RS) yield of nearly 100%. C. butyricum CGS5 could utilize RS from C. vulgaris ESP6 biomass to produce hydrogen without any additional organic carbon sources. The optimal conditions for hydrogen production were 37 °C and a microalgal hydrolysate loading of 9 g RS/L with pH-controlled at 5.5. Under the optimal conditions, the cumulative H2 production, H2 production rate, and H2 yield were 1476 ml/L, 246 ml/L/h, and 1.15 mol/mol RS, respectively. The results demonstrate that the C. vulgaris biomass has the potential to serve as effective feedstock for dark fermentative H2 production. 相似文献
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Rathnasiri G. Puhulwella Laurent Beckers Frank Delvigne Alina S. Grigorescu Philippe Thonart Serge Hiligsmann 《International Journal of Hydrogen Energy》2014
This study investigates the mesophilic biohydrogen production from glucose using a strictly anaerobic strain, Clostridium butyricum CWBI1009, immobilized in a trickling bed sequenced batch reactor (TBSBR) packed with a Lantec HD Q-PAC® packing material (132 ft2/ft3 specific surface). The reactor was operated for 62 days. The main parameters measured here were hydrogen composition, hydrogen production rate and soluble metabolic products. pH, temperature, recirculation flow rate and inlet glucose concentration at 10 g/L were the controlled parameters. The maximum specific hydrogen production rate and the hydrogen yield found from this study were 146 mmol H2/L.d and 1.67 mol H2/mol glucose. The maximum hydrogen composition was 83%. Following a thermal treatment, the culture was active without adding fresh inoculum in the subsequent feeding and both the hydrogen yield and the hydrogen production rate were improved. For all sequences, the soluble metabolites were dominated by the presence of butyric and acetic acids compared to other volatile fatty acids. The results from the standard biohydrogen production (BHP) test which was conducted using samples from TBSBR as inoculum confirmed that the culture generated more biogas and hydrogen compared to the pure strain of C. butyricum CWBI1009. The effect of biofilm activity was studied by completely removing (100%) the mixed liquid and by adding fresh medium with glucose. For three subsequent sequences, similar results were recorded as in the previous sequences with 40% removal of spent medium. The TBSBR biofilm density varied from top to bottom in the packing bed and the highest biofilm density was found at the bottom plates. Moreover, no clogging was evidenced in this packing material, which is characterized by a relatively high specific surface area. Following a PCA test, contaminants of the Bacillus genus were isolated and a standard BHP test was conducted, resulting in no hydrogen production. 相似文献
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A hydrogen producing strain newly isolated from anaerobic sludge in an anaerobic bioreactor, was identified as Clostridium beijerinckii Fanp3 by 16S rDNA gene sequence analysis and detection by BioMerieux Vitek. The strain could utilize various carbon and nitrogen sources to produce hydrogen, which indicates that it has the potential of converting renewable wastes into hydrogen. In batch cultivations, the optimal initial pH of the culture medium was between 6.47 and 6.98. Using 0.15 M phosphate as buffer could alleviate the medium acidification and improve the overall performance of C. beijerinckii Fanp3 in hydrogen production. Culture temperature of 35 °C was established to be the most favorable for maximum rate of hydrogen production. The distribution of soluble metabolic products (SMP) was also greatly affected by temperature. Considering glucose as a substrate, the activation energy (Ea) for hydrogen production was calculated as 81.01 kcal/mol and 21.4% of substrate energy was recovered in the form of hydrogen. The maximal hydrogen yield and the hydrogen production rate were obtained as 2.52 mol/mol-glucose and 39.0 ml/g-glucose h−1, respectively. These results indicate that C. beijerinckii Fanp3 is an ideal candidate for the fermentative hydrogen production. 相似文献
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Mei-Ling Chong Raha Abdul Rahim Yoshihito Shirai Mohd Ali Hassan 《International Journal of Hydrogen Energy》2009
A hydrogen producer was successfully isolated from anaerobic digested palm oil mill effluent (POME) sludge. The strain, designated as Clostridium butyricum EB6, efficiently produced hydrogen concurrently with cell growth. A controlled study was done on a synthetic medium at an initial pH value of 6.0 with 10 g/L glucose with the maximum hydrogen production at 948 mL H2/L-medium and the volumetric hydrogen production rate at 172 mL H2/L-medium/h. The supplementation of yeast extract was shown to have a significant effect with a maximum hydrogen production of 992 mL H2/L-medium at 4 g/L of yeast extract added. The effect of pH on hydrogen production from POME was investigated. Experimental results showed that the optimum hydrogen production ability occurred at pH 5.5. The maximum hydrogen production and maximum volumetric hydrogen production rate were at 3195 mL H2/L-medium and 1034 mL H2/L-medium/h, respectively. The hydrogen content in the biogas produced was in the range of 60–70%. 相似文献
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Fermentative hydrogen production by strict anaerobes has been widely reported. There is a lack of information related to metabolic flux distribution and its variation with respect to fermentation conditions in the metabolic production system. This study aimed to get a better understanding of the metabolic network and to conduct metabolic flux analysis (MFA) of fermentative hydrogen production by a recently isolated Clostridium butyricum strain W5. We chose the specific growth rate as the objective function and used specific H2 production rate as the criterion to evaluate the experimental results with the in silico MFA. For the first time, we constructed an in silico metabolic flux model for the anaerobic glucose metabolism of C. butyricum W5 with assistance of a modeling program MetaFluxNet. The model was used to evaluate metabolic flux distribution in the fermentative hydrogen production network, and to study the fractional flux response to variations in initial glucose concentration and operational pH. The MFA results suggested that pH has a more significant effect on hydrogen production yield compared to the glucose concentration. The MFA is a useful tool to provide valuable information for optimization and design of the fermentative hydrogen production process. 相似文献
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Sakchai PattraChyi-How Lay Chiu-Yue LinSompong O-Thong Alissara Reungsang 《International Journal of Hydrogen Energy》2011,36(14):8697-8703
Non-sterile operation of continuous stirred tank reactor (CSTR) augmented with Clostridium butyricum and fed with sugarcane juice was studied at various hydraulic retention time (HRT). The maximum hydrogen production rate and yield of 3.38 mmol H2/L/h and 1.0 mol H2/mol hexose consumed, respectively, were achieved at HRT 4 h. The relationship of the augmented microorganism and normal flora in the fermentation system under non-sterile condition were analyzed by polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE). Initially, at HRT 36 h, other species related to Lactobacillus harbinensis and Klebseilla pneumoniae were present as a major group in the reactor. When HRT was decreased to 12, 6 and 4 h, C. butyricum was present with a competition between L. harbinensis and K. pneumoniae. Results indicated that augmented C. butyricum could compete with contaminated microorganisms during non-sterile operation at low HRT (12-4 h) with the support of normal flora (K. pneumoniae). 相似文献
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H.S. Jayasinghearachchi Sneha Singh Priyangshu M. Sarma Anil Aginihotri Banwari Lal 《International Journal of Hydrogen Energy》2010
The present study investigated hydrogen production potential of novel marine Clostridium amygdalinum strain C9 isolated from oil water mixtures. Batch fermentations were carried out to determine the optimal conditions for the maximum hydrogen production on xylan, xylose, arabinose and starch. Maximum hydrogen production was pH and substrate dependant. The strain C9 favored optimum pH 7.5 (40 mmol H2/g xylan) from xylan, pH 7.5–8.5 from xylose (2.2–2.5 mol H2/mol xylose), pH 8.5 from arabinose (1.78 mol H2/mol arabinose) and pH 7.5 from starch (390 ml H2/g starch). But the strain C9 exhibited mixed type fermentation was exhibited during xylose fermentation. NaCl is required for the growth and hydrogen production. Distribution of volatile fatty acids was initial pH dependant and substrate dependant. Optimum NaCl requirement for maximum hydrogen production is substrate dependant (10 g NaCl/L for xylose and arabinose, and 7.5 g NaCl/L for xylan and starch). 相似文献
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Three different Rhodobacter sphaeroides (RS) strains (RS–NRRL, RS–DSMZ and RS–RV) and their combinations were used for light fermentation of dark fermentation effluent of ground wheat containing volatile fatty acids (VFA). In terms of cumulative hydrogen formation, RS–NRRL performed better than the other two strains producing 48 ml H2 in 180 h. However, RS–RV resulted in the highest hydrogen yield of 250 ml H2 g−1 TVFA. Specific hydrogen production rate (SHPR) with the RS–NRRL was also better in comparison to the others (13.8 ml H2 g−1 biomass h−1). When combinations of those three strains were used, RS–RV + RS–DSMZ resulted in the highest cumulative hydrogen formation (90 ml H2 in 330 h). However, hydrogen yield (693 ml H2 g−1 TVFA) and SHPR (12.1 ml H2 g−1 biomass h−1) were higher with the combination of the three different strains. On the basis of Gompertz equation coefficients mixed culture of the three different strains gave the highest cumulative hydrogen and formation rate probably due to synergistic interaction among the strains. The effects of initial TVFA and NH4–N concentrations on hydrogen formation were investigated for the mixed culture of the three strains. The optimum TVFA and NH4–N concentrations maximizing the hydrogen formation were determined as 2350 and 47 mg L−1, respectively. 相似文献
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Sanjay K.S. Patel Prasun Kumar Sanjeet Mehariya Hemant J. Purohit Jung-Kul Lee Vipin C. Kalia 《International Journal of Hydrogen Energy》2014
Defined co-cultures of hydrogen (H2) producers belonging to Citrobacter, Enterobacter, Klebsiella and Bacillus were used for enhancing the efficiency of biological H2 production. Out of 11 co-cultures consisting of 2–4 strains, two co-cultures composed of Bacillus cereus EGU43, Enterobacter cloacae HPC123, and Klebsiella sp. HPC793 resulted in H2 yield up to 3.0 mol mol−1 of glucose. Up-scaling of the reactor by 16-fold resulted in a corresponding increase in H2 production with an actual evolution of 7.44 L of H2. It constituted 58.2% of the total biogas. Continuous culture evolution of H2 by co-cultures (B. cereus EGU43 and E. cloacae HPC123) immobilized on ligno-cellulosic materials resulted in 6.4-fold improvement in H2 yield compared to free floating bacteria. This synergistic influence of B. cereus and E. cloacae can offer a better strategy for H2 production than undefined or mixed cultures. 相似文献
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Sanjukta Subudhi Tanmaya Nayak N. Ram KumarP. Vijayananth Banwari Lal 《International Journal of Hydrogen Energy》2013
A hydrogen producing facultative anaerobic alkaline tolerant novel bacterial strain was isolated from crude oil contaminated soil and identified as Enterobacter cloacae DT-1 based on 16S rRNA gene sequence analysis. DT-1 strain could utilize various carbon sources; glycerol, CMCellulose, glucose and xylose, which demonstrates that DT-1 has potential for hydrogen generation from renewable wastes. Batch fermentative studies were carried out for optimization of pH and Fe2+ concentration. DT-1 could generate hydrogen at wide range of pH (5–10) at 37 °C. Optimum pH was; 8, at which maximum hydrogen was obtained from glucose (32 mmol/L), when used as substrate in BSH medium containing 5 mg/L Fe2+ ion. Decrease in hydrogen partial pressure by lowering the total pressure in the fermenter head space, enhanced the hydrogen production performance of DT-1 from 32 mmol H2/L to 42 mmol H2/L from glucose and from 19 mmol H2/L to 33 mmol H2/L from xylose. Hydrogen yield efficiency (HY) of DT-1 from glucose and xylose was 1.4 mol H2/mol glucose and 2.2 mol H2/mol xylose, respectively. Scale up of batch fermentative hydrogen production in proto scale (20 L working volume) at regulated pH, enhanced the HY efficiency of DT-1 from 2.2 to 2.8 mol H2/mol xylose (1.27 fold increase in HY from laboratory scale). 84% of maximum theoretical possible HY efficiency from xylose was achieved by DT-1. Acetate and ethanol were the major metabolites generated during hydrogen production. 相似文献
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Serge Hiligsmann Laurent BeckersJulien Masset Christopher HamiltonPhilippe Thonart 《International Journal of Hydrogen Energy》2014
A horizontal tubular fixed bed bioreactor (HFBR) and an anaerobic biodisc-like reactor (AnBDR) were designed to both fix Clostridium biomass and enable rapid transfer of the hydrogen produced to gas phase in order to decrease the strong effect of H2 partial pressure and H2 supersaturation on the performances of Clostridium strains. The highest H2 production rate (703 mL H2/L h) and yield (302 mL/g glucose consumed i.e. 2.4 mol/mol) with the pure culture were recorded in the AnBDR with 300 mL culture medium (total volume 2.3 L) at pH 5.2 and a glucose loading rate of 2.87 g/L h. These results are about 2.3 and 1.3-fold higher than those achieved in the same bioreactor with 500 mL liquid medium and with the same glucose consumption rate. Therefore, our experimentations and a short review of the literature reported in this paper emphasize the relevance of performing bioreactors with high L/G transfer. 相似文献
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Three bacteria, named L2, L3 and L4, were isolated from contaminated cultures of Chlamydomonas reinhardtii strain cc849 in laboratory. The phylogenetic analysis based on 16S rDNA sequences showed that L2, L3 and L4 belonged to genus Stenotrophomonas, Microbacterium and Pseudomonas, respectively. The co-cultivation of isolated L2, L3 and L4 with purified algae, respectively, demonstrated that moderate bacterial concentration did not affect algal growth significantly but improved algal H2 production obviously. The maximal H2 yields were gained by the co-culture of algae with L2 or L4, about 4.0 times higher than that of the single algal culture. Increased respiration rate or O2 consumption was the main reason for the enhancement of H2 yield of the co-cultures. 相似文献
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Ling Jiang Liying Zhu Xian Xu Ming Lin Yanping Li Xiaotong Li Huaiyan Cui He Huang 《International Journal of Hydrogen Energy》2013
Laboratory mutagenesis of microorganisms offers the possibility of relating acquired mutations to improve the quality of microbial cultures. In the present study, a mutant strain, Clostridium tyrobutyricum ATCC 25755 DG-8, with significantly elevated α-amylase activity as well as resistant to the non-metabolizable and toxic glucose analog 2-deoxyglucose (2-DG) was obtained by implanting the low-energy nitrogen ion beam. DG-8 was further developed to produce hydrogen by simultaneous saccharification and fermentation (SSF) directly form cassava starch in batch fermentation mode, which to our knowledge is at the first attempt in genus Clostridium. Our results demonstrated that the increased activity of α-amylase would be attributed to the hydrogen over-producing. Higher hydrogen yield (3.2 mol/mol glucose) was achieved with the volumetric productivity of 0.41 L/h/L when the initial total sugar concentration of cassava starch rise up to 100 g/L. The present work will help to decrease the cost of hydrogen fermentation process and stimulate its industrial application in the near future. 相似文献
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Xiaofeng Ye Xinyu Zhang Eberhard Morgenroth Kevin T. Finneran 《International Journal of Hydrogen Energy》2012
Fermentative hydrogen production is considered a reasonable alternative for generating H2 as an energy carrier for electricity production using hydrogen fuel cells. The kinetics of hydrogen production from glucose, xylose and cellobiose were investigated using pure culture Clostridium beijerinckii NCIMB 8052. Adding anthrahydroquinone-2,6-disulfonate (AH2QDS) at concentrations ranging from 100 μM to 500 μM increased the hydrogen production rates from 0.80 to 1.35 mmol/L-hr to 1.20–2.70 mmol/L-hr with glucose, xylose, or cellobiose as the primary substrates. AH2QDS amendment also increased the substrate utilization rate and biomass growth rate by at least two times. These findings suggest that adding hydroquinone reducing equivalents influence cellular metabolism with hydrogen production rate, substrate utilization rate, and growth rate being simultaneously affected. Resting cell suspensions were conducted to investigate the influence of AH2QDS on the hydrogen production rate from glyceraldehyde 3-phosphate, which is a shared intermediate in both glycolysis and pentose phosphate pathway. Data demonstrated that hydrogen production rate increased by 1.5 times when glyceraldehyde 3-phosphate was the sole carbon source, suggesting that the hydroquinone may alter reactions starting with or after glyceraldehyde 3-phosphate in central metabolism. These data demonstrate that adding hydroquinones increased overall metabolic activity of C. beijerinckii. This will eventually increase the efficiency of industrial scale production once appropriate hydroquinone equivalents are identified that work well in large-scale operations, since fermentation rate is one of the two critical factors (production rate and yield) influencing efficiency and cost. 相似文献
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Lijing Jiang Chuannan Long Xiaobing Wu Hongxiu Xu Zongze Shao Minnan Long 《International Journal of Hydrogen Energy》2014
A unique thermophilic fermentative hydrogen-producing strain H53214 was isolated from a deep-sea hydrothermal vent environment, and identified as Caloranaerobacter azorensis based on bacterial 16S rRNA gene analysis. The optimum culture condition for hydrogen production by the bacterium, designated C. azorensis H53214, was investigated by the response surface methodology (RSM). Eight variables including the concentration of NaCl, glucose, yeast, tryptone, FeSO4 and MgSO4, initial pH and incubation temperature were screened based on the Plackett–Burman design. The results showed that initial pH, tryptone and yeast were significant variables, which were further optimized using the steepest ascent method and Box–Behnken design. The optimal culture conditions for hydrogen production were an initial pH of 7.7, 8.3 g L−1 tryptone and 7.9 g L−1 yeast. Under these conditions, the maximum cumulative hydrogen volume, hydrogen yield and maximum H2 production rate were 1.58 L H2 L−1 medium, 1.46 mol H2 mol−1 glucose and 25.7 mmol H2 g−1 cell dry weight (CDW) h−1, respectively. By comparison analysis, strain H53214 was superior to the most thermophilic hydrogen producers because of the high hydrogen production rate. In addition, the isolation of C. azorensis H53214 indicated the deep-sea hydrothermal environment might be a potential source for fermentative hydrogen-producing thermophiles. 相似文献
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A thermotolerant fermentative hydrogen-producing strain was isolated from crude glycerol contaminated soil and identified as Klebsiella pneumoniae on the basis of the 16S rRNA gene analysis as well as physiological and biochemical characteristics. The selected strain, designated as K. pneumoniae TR17, gave good hydrogen production from crude glycerol. Culture conditions influencing the hydrogen production were investigated. The strain produced hydrogen within a wide range of temperature (30–50 °C), initial pH (4.0–9.0) and crude glycerol concentration (20–100 g/L) with yeast extract as a favorable nitrogen source. In batch cultivation, the optimal conditions for hydrogen production were: cultivation temperature at 40 °C, initial pH at 8.0, 20 g/L crude glycerol and 2 g/L yeast extract. This resulted in the maximum cumulative hydrogen production of 27.7 mmol H2/L and hydrogen yield of 0.25 mol H2/mol glycerol. In addition, the main soluble metabolites were 1,3-propanediol, 2,3-butanediol and ethanol corresponding to the production of 3.52, 2.06 and 3.95 g/L, respectively. 相似文献