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1.
Microbial fed-batch production of 1,3-propanediol by Klebsiella pneumoniae under micro-aerobic conditions 总被引:6,自引:0,他引:6
The microbial production of 1,3-propanediol (1,3-PD) by Klebsiella pneumoniae under micro-aerobic conditions was investigated in this study. The experimental results of batch fermentation showed that the final concentration and yield of 1,3-PD on glycerol under micro-aerobic conditions approached values achieved under anaerobic conditions. However, less ethanol was produced under microaerobic than anaerobic conditions at the end of fermentation. The batch micro-aerobic fermentation time was markedly shorter than that of anaerobic fermentation. This led to an increment of productivity of 1,3-PD. For instance, the concentration, molar yield, and productivity of 1,3-PD of batch micro-aerobic fermentation by K. pneumoniae DSM 2026 were 17.65 g/l, 56.13%, and 2.94 g l–1 h–1, respectively, with a fermentation time of 6 h and an initial glycerol concentration of 40 g/l. Compared with DSM 2026, the microbial growth of K. pneumoniae AS 1.1736 was slow and the concentration of 1,3-PD was low under the same conditions. Furthermore, the microbial growth in fed-batch fermentation by K. pneumoniae DSM 2026 was faster under micro-aerobic than anaerobic conditions. The concentration, molar yield, and productivity of 1,3-PD in fed-batch fermentation under micro-aerobic conditions were 59.50 g/l, 51.75%, and 1.57 g l–1 h–1, respectively. The volumetric productivity of 1,3-PD under microaerobic conditions was almost twice that of anaerobic fed-batch fermentation, at 1.57 and 0.80 g l–1 h–1, respectively. 相似文献
2.
1,3-Propanediol (1,3-PD) can be produced from glycerol by Klebsiella pneumoniae under micro-aerobic conditions. Recently, this fed-batch fermentation process has been successfully scaled up to 1 m3. The final 1,3-PD concentration, molar yield and volumetric productivity of 72 g l−1, 57% and 2.1 g l−1 h−1, respectively, are close to those of 75 g l−1, 61%, and 2.2 g l−1 h−1 under anaerobic conditions. This process would be suitable for the production of 1,3-PD on a large scale. 相似文献
3.
Zong-Ming Zheng Yun-Zhen Xu Ti-Peng Wang Chang-Qing Dong Yong-Ping Yang De-Hua Liu 《Biotechnology letters》2010,32(2):289-294
Excretion of 1,3-propanediol (1,3-PD) by K. pneumoniae was compared in ammonium- and phosphate-limited chemostat cultures running with an excess of glycerol. 59 and 43% catabolic
flux were directed to 1,3-PD in ammonia-limited cultures and phosphate-limited cultures at dilution rate of 0.1 h−1, respectively. Ammonia-limited fed-batch cultures produced 61 g 1,3-PD l−1 and a total of 15 g l−1 organic acid in 36 h. However, phosphate-limited fed-batch cultures excreted 61 g lactate l−1 and 44 g 1,3-PD l−1. 相似文献
4.
Ni-Ni Guo Zong-Ming Zheng Yu-Lin Mai Hong-Juan Liu De-Hua Liu 《Applied microbiology and biotechnology》2010,86(2):701-707
The filtration in 1,3-propanediol (1,3-PD) downstream process is influenced by the large amounts of capsular polysaccharides
(CPS) produced by Klebsiella pneumoniae CGMCC 1.6366. The morphological and fermentation properties were investigated with the CPS-deficient mutant K. pneumoniae CGMCC 1.6366 CPS. Similar biomass was obtained with CGMCC 1.6366, and the mutant strain in batch cultures indicating the
cell growth was slightly inhibited by CPS defection. The viscosity of fermentation broth by mutant strain decreased by 27.45%.
The flux with ceramic membrane filter was enhanced from 168.12 to 303.6 l h−1 m−2, exhibiting the great importance for downstream processing of 1,3-PD fermentation. The products spectrum of mutant isolate
changed remarkably regarding to the concentration of fermentation products. The synthesis of important 1,3-PD and 2,3-butanediol
was enhanced from 9.73 and 4.06 g l−1 to 10.37 and 4.77 g l−1 in batch cultures. The noncapsuled K. pneumoniae provided higher 1,3-PD yield of 0.54 mol mol−1 than that of encapsuled wild parent in batch cultures. The fed-batch fermentation of mutant strain resulted in 1,3-PD concentration,
yield, and productivity of 78.13 g l−1, 0.53 mol mol−1, and 1.95 g l−1 h−1, respectively. 相似文献
5.
Yuanhao Wang Hu Teng Zhilong Xiu 《Journal of industrial microbiology & biotechnology》2011,38(6):705-715
The microbial production of 1,3-propaneidol (1,3-PD) by Klebsiella pneumoniae in continuous fermentation was investigated under low, medium and high glycerol concentrations in the absence and presence
of oxygen. The production of 1,3-PD increased with increasing glycerol concentrations, reaching a maximum (266 mmol l−1) under high glycerol concentration (760 mmol l−1) with air sparging at 0.04 vvm. The yield of 1,3-PD, however, decreased gradually with increasing glycerol concentrations,
with the highest yield (0.52 mol mol−1) obtained for low glycerol concentration (270 mmol l−1) under anaerobic condition. Enzyme activity assays showed that the specific activity of glycerol dehydratase was highest
(0.04 U mg−1) for culture sparged with 0.04 vvm air under high glycerol concentration. The specific activities of glycerol dehydrogenase
and 1,3-propanediol oxidoreductase were also improved for all glycerol concentrations and in the presence of oxygen, implying
that the dha operon was not repressed under microaerobic conditions. Analysis of metabolic fluxes showed that more carbon flux was shifted
to the oxidative pathway with increasing glycerol concentrations, resulting in a reduced flux to 1,3-PD formation. However,
the increases in carbon fluxes were not evenly distributed among the oxidative branches of the pathway. Furthermore, ethanol
and acetic acid levels were slightly increased whereas 2,3-butanediol and lactic levels were greatly enhanced. 相似文献
6.
Industrial waste corn cob residue (from xylose manufacturing) without pretreatment was hydrolyzed by cellulase and cellobiase. The cellulosic hydrolysate contained 52.4 g l−1 of glucose and was used as carbon source for lactic acid fermentation by cells of Lactobacillus delbrueckii ZU-S2 immobilized in calcium alginate gel beads. The final concentration of lactic acid and the yield of lactic acid from glucose were 48.7 g l−1 and 95.2%, respectively, which were comparative to the results of pure glucose fermentation. The immobilized cells were quite stable and reusable, and the average yield of lactic acid from glucose in the hydrolysate was 95.0% in 12 repeated batches of fermentation. The suitable dilution rate of continuous fermentation process was 0.13 h−1, and the yield of lactic acid from glucose and the productivity were 92.4% and 5.746 g l−1 h−1, respectively. The production of lactic acid by simultaneous saccharification and fermentation (SSF) process was carried out in a coupling bioreactor, the final concentration of lactic acid was 55.6 g l−1, the conversion efficiency of lactic acid from cellulose was 91.3% and the productivity was 0.927 g l−1 h−1. By using fed-batch technique in the SSF process, the final concentration of lactic acid and the productivity increased to 107.6 g l−1 and 1.345 g l−1 h−1, respectively, while the dosage of cellulase per gram substrate decreased greatly. This research work should advance the bioconversion of renewable cellulosic resources and reduce environmental pollution. 相似文献
7.
Xuedong Xue Wei Li Zhimin Li Yuelan Xia Qin Ye 《Journal of industrial microbiology & biotechnology》2010,37(7):681-687
In fed-batch culture of Klebsiella pneumoniae, 1,3-propanediol production was growth associated, while the by-products, including lactic acid and ethanol, increased sharply
as the cells grew slowly. When the fed-batch culture was supplied with a mixture of organic acids including citrate, fumarate
and succinate, cell growth and 1,3-propanediol production increased significantly, whereas the by-products, especially lactic
acid and ethanol, decreased sharply. High concentrations of PDO and acetate inhibited cell growth and PDO production. To improve
the PDO production, repeated fed-batch culture with addition of the organic acid mixture was performed in a 5-l reactor. The
fed-batch culture was repeated five times, and the 1,3-propanediol yield and concentration reached above 0.61 mol mol−1 and 66 g l−1, respectively, in 20 h for each cycle. Furthermore, the PDO productivity reached above 3.30 g l−1 h−1 in each cycle, which was much higher than that of the original fed-batch culture. 相似文献
8.
Okano K Kimura S Narita J Fukuda H Kondo A 《Applied microbiology and biotechnology》2007,75(5):1007-1013
To achieve direct and efficient lactic acid production from starch, a genetically modified Lactococcus lactis IL 1403 secreting α-amylase, which was obtained from Streptococcus bovis 148, was constructed. Using this strain, the fermentation of soluble starch was achieved, although its rate was far from
efficient (0.09 g l−1 h−1 lactate). High-performance liquid chromatography revealed that maltose accumulated during fermentation, and this was thought
to lead to inefficient fermentation. To accelerate maltose consumption, starch fermentation was examined using L. lactis cells adapted to maltose instead of glucose. This led to a decrease in the amount of maltose accumulation in the culture,
and, as a result, a more rapid fermentation was accomplished (1.31 g l−1 h−1 lactate). Maximum volumetric lactate productivity was further increased (1.57 g l−1 h−1 lactate) using cells adapted to starch, and a high yield of lactate (0.89 g of lactate per gram of consumed sugar) of high
optical purity (99.2% of l-lactate) was achieved. In this study, we propose a new approach to lactate production by α-amylase-secreting L. lactis that allows efficient fermentation from starch using cells adapted to maltose or starch before fermentation. 相似文献
9.
Kim JH Han KC Koh YH Ryu YW Seo JH 《Journal of industrial microbiology & biotechnology》2002,29(1):16-19
Xylitol, a functional sweetener, was produced from xylose by biological conversion using Candida tropicalis ATCC 13803. Based on a two-substrate fermentation using glucose for cell growth and xylose for xylitol production, fed-batch
fermentations were undertaken to increase the final xylitol concentration. The effects of xylose and xylitol on xylitol production
rate were studied to determine the optimum concentrations for fed-batch fermentation. Xylose concentration in the medium (100
g l−1) and less than 200 g l−1 total xylose plus xylitol concentration were determined as optimum for maximum xylitol production rate and xylitol yield.
Increasing the concentrations of xylose and xylitol decreased the rate and yield of xylitol production and the specific cell
growth rate, probably because of an increase in osmotic stress that would interfere with xylose transport, xylitol flux to
secretion to cell metabolism. The feeding rate of xylose solution during the fed-batch mode of operation was determined by
using the mass balance equations and kinetic parameters involved in the equations in order to increase final xylitol concentration
without affecting xylitol and productivity. The optimized fed-batch fermentation resulted in 187 g l−1 xylitol concentration, 0.75 g xylitol g xylose−1 xylitol yield and 3.9 g xylitol l−1 h−1 volumetric productivity. Journal of Industrial Microbiology & Biotechnology (2002) 29, 16–19 doi:10.1038/sj.jim.7000257
Received 15 October 2001/ Accepted in revised form 30 March 2002 相似文献
10.
Microbial production of 1,3-propanediol by Klebsiella pneumoniae using crude glycerol from biodiesel preparations 总被引:3,自引:0,他引:3
1,3-Propanediol (1,3-PD) was produced by Klebsiella pneumoniae using crude glycerol obtained from biodiesel production. The 1,3-PD concentration of 51.3 g/l−1 on crude glycerol from alkali-catalyzed methanolysis of soybean oil was comparable to that of 53 g/l−1 on crude glycerol derived from a lipase-catalyzed process. The productivities of 1.7 g l−1 h−1 on crude glycerol were comparable to that of 2 g l−1 h−1 on pure glycerol. It could be concluded that the crude glycerol could be directly converted to 1,3-PD without any prior purification. 相似文献
11.
Lian Hua Luo Jeong-Woo Seo Baek-Rock Oh Pil-Soo Seo Sun-Yeon Heo Won-Kyung Hong Dae-Hyuk Kim Chul Ho Kim 《Journal of industrial microbiology & biotechnology》2011,38(8):991-999
Previously, we constructed a glycerol oxidative pathway-deficient mutant strain of Klebsiella pneumoniae by inactivation of glycerol dehydrogenase (dhaD) to eliminate by-product synthesis during production of 1,3-propanediol (1,3-PD) from glycerol. Although by-product formation
was successfully blocked in the resultant strain, the yield of 1,3-PD was not enhanced, probably because dhaD disruption resulted in insufficient regeneration of the cofactor NADH essential for the activity of 1,3-PD oxidoreductase
(DhaT). To improve cofactor regeneration, in the present study we overexpressed an NAD+-dependent aldehyde dehydrogenase in the recombinant strain. To this end, an aldehyde dehydrogenase AldHk homologous to E. coli AldH but with NAD+-dependent propionaldehyde dehydrogenase activity was identified in K. pneumoniae. Functional analysis revealed that the substrate specificity of AldHk embraced various aldehydes including propionaldehyde,
and that NAD+ was preferred over NADP+ as a cofactor. Overexpression of AldHk in the glycerol oxidative pathway-deficient mutant AK/pVOTHk resulted in a 3.6-fold
increase (0.57 g l−1 to 2.07 g l−1) in the production of 3-hydroxypropionic acid (3-HP), and a 1.1-fold enhancement (8.43 g l−1 to 9.65 g l−1) of 1,3-PD synthesis, when glycerol was provided as the carbon source, compared to the levels synthesized by the control
strain (AK/pVOT). Batch fermentation using AK/pVOTHk showed a significant increase (to 70%, w/w) in conversion of glycerol
to the reductive metabolites, 1,3-PD and 3-HP, with no production of by-products except acetate. 相似文献
12.
Lactic acid production was investigated for batch and repeated batch cultures of Enterococcus faecalis RKY1, using wood hydrolyzate and corn steep liquor. When wood hydrolyzate (equivalent to 50 g l−1 glucose) supplemented with 15–60 g l−1 corn steep liquor was used as a raw material for fermentation, up to 48.6 g l−1 of lactic acid was produced with, volumetric productivities ranging between 0.8 and 1.4 g l−1 h−1. When a medium containing wood hydrolyzate and 15 g l−1 corn steep liquor was supplemented with 1.5 g l−1 yeast extract, we observed 1.9-fold and 1.6-fold increases in lactic acid productivity and cell growth, respectively. In this case, the nitrogen source cost for producing 1 kg lactic acid can be reduced to 23% of that for fermentation from wood hydrolyzate using 15 g l−1 yeast extract as a single nitrogen source. In addition, lactic acid productivity could be maximized by conducting a cell-recycle repeated batch culture of E. faecalis RKY1. The maximum productivity for this process was determined to be 4.0 g l−1 h−1. 相似文献
13.
《Applied microbiology and biotechnology》2008,78(6):1089-1343
Poly(3-hydroxybutyrate) (PHB) synthesis was analyzed under microaerobic conditions in a recombinant Escherichia coli arcA mutant using glycerol as the main carbon source. The effect of several additives was assessed in a semi-synthetic medium
by the ‘one-factor-at-a-time’ technique. Casein amino acids (CAS) concentration was an important factor influencing both growth
and PHB accumulation. Three factors exerting a statistically significant influence on PHB synthesis were selected by using
a Plackett–Burman screening design [glycerol, CAS, and initial cell dry weight (CDW) concentrations] and then optimized through
a Box–Wilson design. Under such optimized conditions (22.02 g l−1 glycerol, 1.78 g l−1 CAS, and 1.83 g l−1 inoculum) microaerobic batch cultures gave rise to 8.37 g l−1 CDW and 3.52 g l−1 PHB in 48 h (PHB content of 42%) in a benchtop bioreactor. Further improvements in microaerobic PHB accumulation were obtained
in fed-batch cultures, in which glycerol was added to maintain its concentration above 5 g l−1. After 60 h, CDW and PHB concentration reached 21.17 and 10.81 g l−1, respectively, which results in a PHB content of 51%. Microaerobic fed-batch cultures allowed a 2.57-fold increase in volumetric
productivity when compared with batch cultures.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
An erratum to this article can be found at 相似文献
14.
Fermentative production of lactic acid from biomass: an overview on process developments and future perspectives 总被引:6,自引:0,他引:6
The concept of utilizing excess biomass or wastes from agricultural and agro-industrial residues to produce energy, feeds
or foods, and other useful products is not necessarily new. Recently, fermentation of biomass has gained considerable attention
due to the forthcoming scarcity of fossil fuels and also due to the necessity of increasing world food and feed supplies.
A cost-effective viable process for lactic acid production has to be developed for which several attempts have been initiated.
Fermentation techniques result in the production of either d (−) or l (+) lactic acid, or a racemic mixture of both, depending on the type of organism used. The interest in the fermentative production
of lactic acid has increased due to the prospects of environmental friendliness and of using renewable resources instead of
petrochemicals. Amylolytic bacteria Lactobacillus amylovorus ATCC 33622 is reported to have the efficiency of full conversion of liquefied cornstarch to lactic acid with a productivity
of 20 g l−1 h−1. A maximum of 35 g l−1 h−1 was reported using a high cell density of L. helveticus (27 g l−1) with a complete conversion of 55- to 60-g l−1 lactose present in whey. Simultaneous saccharification and fermentation is proved to be best in the sense of high substrate
concentration in lower reactor volume and low fermentation cost. In this review, a survey has been made to see how effectively
the fermentation technology explored and exploited the cheaply available source materials for value addition with special
emphasis on lactic acid production. 相似文献
15.
Broth containing 152 g glycerol l−1 from Candida krusei culture was converted to 1,3-propanediol by Klebsiella pneumoniae. Residual glucose in the broth promoted growth of K. pneumoniae while acetate was inhibitory. After desalination treatment of glycerol broth by electrodialysis, the acetate in the broth was removed. A fed-batch culture with electrodialytically pretreated broth as␣substrate was developed giving 53 g 1,3- propanediol l−1 with a yield of 0.41 g g−1 glycerol and a productivity of 0.94 g l−1 h−1. 相似文献
16.
Y-W Ryu C Y Park J B Park S-Y Kim J-H Seo 《Journal of industrial microbiology & biotechnology》2000,25(2):100-103
A two-stage fed-batch process was designed to enhance erythritol productivity by the mutant strain of Candida magnoliae. The first stage (or growth stage) was performed in the fed-batch mode where the growth medium was fed when the pH of the
culture broth dropped below 4.5. The second stage (or production stage) was started with addition of glucose powder into the
culture broth when the cell mass reached about 75 g dry cell weight l−1. When the initial glucose concentration was adjusted to 400 g l−1 in the production stage, 2.8 g l−1 h−1 of overall erythritol productivity and 41% of erythritol conversion yield were achieved, which represented a fivefold increase
in erythritol productivity compared with the simple batch fermentation process. A high glucose concentration in the production
phase resulted in formation of organic acids including citrate and butyrate. An increase in dissolved oxygen level caused
formation of gluconic acid instead of citric acid. Journal of Industrial Microbiology & Biotechnology (2000) 25, 100–103.
Received 25 February 2000/ Accepted in revised form 08 June 2000 相似文献
17.
Instead of the conventional carbon sources used for propionic acid biosynthesis, the utilization of glycerol is considered
here, since the metabolic pathway involved in the conversion of glycerol to propionic acid is redox-neutral and energetic.
Three strains, Propionibacterium acidipropionici, Propionibacterium acnes and Clostridium propionicum were tested for their ability to convert glycerol to propionic acid during batch fermentation with initially 20 g/l glycerol.
P. acidipropionici showed higher efficiency in terms of fermentation time and conversion yield than did the other strains. The fermentation
profile of this bacterium consisted in propionic acid as the major product (0.844 mol/mol), and in minimal by-products: succinic
(0.055 mol/mol), acetic (0.023 mol/mol) and formic (0.020 mol/mol) acids and n-propanol (0.036 mol/mol). The overall propionic acid productivity was 0.18 g l−1h−1. A comparative study with glucose and lactic acid as carbon sources showed both less diversity in end-product composition
and a 17% and 13% lower propionic acid conversion yield respectively than with glycerol. Increasing the initial glycerol concentration
resulted in an enhanced productivity up to 0.36 g l−1h−1 and in a maximal propionic acid concentration of 42 g/l, while a slight decrease of the conversion yield was noticed. Such
a propionic acid production rate was similar or higher than the values obtained with lactic acid (0.35 g l−1h−1) or glucose (0.28 g l−1h−1). These results demonstrated that glycerol is a carbon source of interest for propionic acid production.
Received: 15 July 1996 / Received revision: 11 November 1996 / Accepted: 11 November 1996 相似文献
18.
Production of 1,3-Propanediol by Clostridium butyricum VPI 3266 in continuous cultures with high yield and productivity 总被引:2,自引:0,他引:2
González-Pajuelo M Andrade JC Vasconcelos I 《Journal of industrial microbiology & biotechnology》2005,32(9):391-396
The effects of dilution rate and substrate feed concentration on continuous glycerol fermentation by Clostridium butyricum VPI 3266, a natural 1,3-propanediol producer, were evaluated in this work. A high and constant 1,3-propanediol yield (around
0.65 mol/mol), close to the theoretical value, was obtained irrespective of substrate feed concentration or dilution rate.
Improvement of 1,3-propanediol volumetric productivity was achieved by increasing the dilution rate, at a fixed feed substrate
concentration of 30, 60 or 70 g l−1. Higher 1,3-propanediol final concentrations and volumetric productivities were also obtained when glycerol feed concentration
was increased from 30 to 60 g l−1, at D=0.05–0.3 h−1, and from 60–70 g l−1, at D=0.05 and 0.1 h−1·30 g l−1 of 1,3-propanediol and the highest reported value of productivity, 10.3 g l−1 h−1, was achieved at D=0.30 h−1 and 60 g l−1 of feed glycerol. A switch to an acetate/butyrate ratio higher than one was observed for 60 g l−1 of feed glycerol and a dilution rate higher than 0.10 h−1; moreover, at D=0.30 h−1 3-hydroxypropionaldehyde accumulation was observed for the first time in the fermentation broth of C. butyricum. 相似文献
19.
Constant medium feeding rate and intermittent fed-batch fermentation strategies were investigated aiming to increase the yields
of γ-decalactone production by Yarrowia lipolytica, using methyl ricinoleate as substrate and ricinoleic acid source. The accumulation of another compound, 3-hydroxy-γ-decalactone,
was also analyzed since it derives from the direct precursor of γ-decalactone thereby providing information about the enzymatic
activities of the pathway. Both strategies were compared with the traditional batch mode in terms of overall productivity
and yield in respect to the substrate. Although the productivity of γ-decalactone was considerably higher in the batch mode
(168 mg l−1 h−1), substrate conversion to lactone (73 mg γ-decalactone g−1) was greater in the intermittent fed-batch giving 6.8 g γ-decalactone l−1. This last strategy therefore has potential for γ-decalactone production at an industrial level. 相似文献
20.
A newly isolated sucrose-tolerant, lactic acid bacterium, Lactobacillus sp. strain FCP2, was grown on sugar-cane juice (125 g sucrose l−1, 8 g glucose l−1 and 6 g fructose l−1) for 5 days and produced 104 g lactic acid l−1 with 90% yield. A higher yield (96%) and productivity (2.8 g l−1 h−1) were obtained when strain FCP2 was cultured on 3% w/v (25 g sucrose l−1, 2 g glucose l−1 and 1 g fructose l−1) sugar-cane juice for 10 h. Various cheap nitrogen sources such as silk worm larvae, beer yeast autolysate and shrimp wastes
were also used as a substitute to yeast extract. 相似文献