共查询到20条相似文献,搜索用时 312 毫秒
1.
Biotechnology of succinic acid production and markets for derived industrial products 总被引:29,自引:4,他引:25
Succinic acid, derived from fermentation of agricultural carbohydrates, has a specialty chemical market in industries producing
food and pharmaceutical products, surfactants and detergents, green solvents and biodegradable plastics, and ingredients to
stimulate animal and plant growth. As a carbon-intermediate chemical, fermentation-derived succinate has the potential to
supply over 2.7 × 108 kg industrial products/year including: 1,4-butanediol, tetrahydrofuran, γ-butyrolactone, adipic acid, n-methylpyrrolidone and linear aliphatic esters. Succinate yields as high as 110 g/l have been achieved from glucose by the
newly discovered rumen organism Actinobacillus succinogenes. Succinate fermentation is a novel process because the greenhouse gas CO2 is fixed into succinate during glucose fermentation. New developments in end-product recovery technology, including water-splitting
electrodialysis and liquid/liquid extraction have lowered the cost of succinic acid production to U.S. $ 0.55/kg at the 75 000
tonne/year level and to $ 2.20/kg at the 5000 tonne/year level. Research directions aimed at further improving the succinate
fermentation economics are discussed.
Received: 27 October 1998 / Received revision: 22 January 1999 / Accepted: 22 January 1999 相似文献
2.
Acetic acid fermentation is the biochemical process by which, under strict conditions of aerobiosis, Acetobacter aceti oxidises the ethanol contained in alcoholic substrates into acetic acid. This paper studies the effect of temperature on
the specific growth rate of the microorganisms (μ
C), in particular, the mathematical modelling of this process, with the aim of developing previous studies of the mathematical
relationships between μ
C of A. aceti and the concentrations of substrate (ethanol), product (acetic acid) and dissolved oxygen. Until now this relationship has
not been widely studied, and only a few studies have looked at the influence of temperature on growth kinetics of this bacteria.
We have developed an extensive experimental system, to determine precisely the influence of temperature on the maximum specific
growth rate.
Received: 15 July 1997 / Received revision: 7 October 1997 / Accepted: 19 October 1997 相似文献
3.
D. Naki C. Paech G. Ganshaw V. Schellenberger 《Applied microbiology and biotechnology》1998,49(3):290-294
Mutants that secrete increased amounts of enzyme into a selection medium can be efficiently enriched from large populations
of mutagenized microorganisms during growth in hollow fibers. Under these conditions, each colony grows in its own microenvironment
and cross-feeding between neighboring colonies is limited. We applied the technique to B. subtilis carrying a plasmid-encoded protease gene. The plasmid was subjected to random mutagenesis and clones secreting up to fivefold-increased
amounts of enzyme were selected using a medium containing bovine serum albumin as the sole nitrogen source.
Received: 22 May 1997 / Received revision: 21 October 1997 / Accepted: 7 November 1997 相似文献
4.
C. J. Israilides A. Smith J. E. Harthill C. Barnett G. Bambalov B. Scanlon 《Applied microbiology and biotechnology》1998,49(5):613-617
Ethanol-precipitated substances after fermentation of various agro-industrial wastes by Aureobasidium pullulans were examined for their pullulan content. Grape skin pulp extract, starch waste, olive oil waste effluents and molasses served
as substrates for the fermentation. A glucose-based defined medium was used for comparison purposes. Samples were analysed
by an enzyme-coupled assay method and by high-performance anion-exchange chromatography with pulsed amperometric detection
after enzymic hydrolysis with pullulanase. Fermentation of grape skin pulp extract gave 22.3 g l−1 ethanol precipitate, which was relatively pure pullulan (97.4% w/w) as assessed by the coupled-enzyme assay. Hydrolysed starch
gave only 12.9 g l−1 ethanol precipitate, which increased to 30.8 g l−1 when the medium was supplemented with NH4NO3 and K2HPO4; this again was relatively pure pullulan (88.6% w/w). Molasses and olive oil wastes produced heterogeneous ethanol-precipitated
substances containing small amounts of pullulan, even when supplemented with nitrogen and phosphate. Overall, grape skin pulp
should be considered as the best substrate for pullulan production. Starch waste requires several hydrolyis steps to provide
a usable carbon source, which reduces its economic attraction as an industrial process.
Received: 24 October 1997 / Received revision: 10 February 1998 / Accepted: 15 February 1998 相似文献
5.
Xanthomonas campestris pv. translucens IFO13599 could produce xanthan gum (18.5 mg/100 mg, lactose) with lactose as the growth substrate in spite of a low level
of β-galactosidase. This productivity corresponded to one-fifth that with glucose. This strain could also produce ice-nucleating
material having an ice-nucleating temperature, T
50, of −2.8 °C with xanthan gum in the culture broth. We found that this strain produced both materials in whey medium from
which the insoluble components had been removed. The production of xanthan with ice-nucleating material reached a maximum
after cultivation for 168 h under optimum conditions. Furthermore, the xanthan obtained had a low viscosity because of its
variant structure revealed, by TLC and HPLC analyses, to be lacking pyruvic acid. Furthermore, we concluded that this mixture
had considerable potential as a regeneratic agent, when compared to other regeneratic agents such as carboxymethylcellulose.
Received: 29 August 1997 / Received revision: 17 November 1997 / Accepted: 18 November 1997 相似文献
6.
U. Mukundan V. Bhide G. Singh W. R. Curtis 《Applied microbiology and biotechnology》1998,50(2):241-245
Brief exposure of Beta vulgaris root cultures to acidic medium resulted in release of betalain pigments while the capability for regrowth and continued pigment
accumulation was retained. A 10-min exposure to pH 2 followed by return to standard growth medium (pH 5.5, 1.1 mM PO4) resulted in release of 0.59 mg pigment/g dry weight over the subsequent 24-h period. The released pigment corresponds to
36.8% of the total pigments. Further improvement in culture productivity was achieved through phosphate limitation. Specific
pigment productivity increased fivefold for cultures grown in phosphate-free medium as compared to cultures grown in control
medium (1.1 mM PO4). A maximum total pigment production of 25.2 mg/l was observed at an initial medium phosphate level 0.3 mM. When combined
with phosphate limitation, low pH facilitated the release of 3.03 mg pigment/g dry weight, which corresponds to 50% of the
total pigment. The permeabilized roots were capable of regrowth and continued pigment accumulation. A cytochemical assay for
respiratory activity revealed that the basis of regrowth was lateral root initials that were unaffected during the acidic
pH treatment.
Received: 16 December 1997 / Received revision: 7 May 1998 / Accepted: 16 May 1998 相似文献
7.
The time courses of growth and rosmarinic acid production by Lavandula vera MM cell suspension were investigated. The uptake of the main nutrients (sucrose, nitrogen, phosphorus, K, Ca, Mg) was followed
during cultivation and the data on the physiology of the L. vera MM cell culture are presented. It was established that the cell culture synthesizes rosmarinic acid during the linear phase
of growth for a relatively short period (between the 4th and 8th days of cultivation). The influence of sucrose concentration
in the nutrient medium on cell growth and accumulation of rosmarinic acid by L. vera MM cell culture was investigated. The results showed that 7% sucrose in the nutrient medium ensured a steady growth of the
cell suspension and increased the yield of rosmarinic acid (29.2 g/l dry biomass and 507.5 mg/l rosmarinic acid compared to
13.0 g/l dry biomass and 68.6 mg/l rosmarinic acid for the control cultivation with 3% sucrose).
Received: 17 September 1996 / Received revision: 31 January 1997 / Accepted: 1 February 1997 相似文献
8.
5-Hydroxypyrazine-2-carboxylic acid, a versatile building block for the synthesis of new antituberculous agents, was prepared
by whole-cell biotransformation from 2-cyanopyrazine via pyrazinecarboxylic acid using Agrobacterium sp. DSM 6336. By developing a fermentation process for this two-enzyme-step bioconversion, a product concentration of 286 mM
(40 g/l) was obtained. After the isolation method had been optimized the total yield was 80%.
Received: 28 February 1997 / Received revision: 28 April 1997 / Accepted: 4 May 1997 相似文献
9.
Physiological aspects of continuous lactic acid fermentations at high dilution rates 总被引:1,自引:0,他引:1
U. Kulozik 《Applied microbiology and biotechnology》1998,49(5):506-510
The effects of the substrate conditions on the volumetric productivity of Lactobacillus helveticus at different cell densities up to 60 g l−1 in a continuous stirred-tank reactor with microfiltration to retain the biomass were investigated. At low dilution rates,
D, the steady-state volumetric productivity, r
p, gradually increased to a maximum at D = 1.2–1.5 h−1, because of reduced product inhibition. At higher D values, r
p unexpectedly decreased, although the substrate conditions further improved. The maxima of r
p at different cell densities coincided with a critical specific substrate utilization rate beyond which the cell metabolism
seems to be controlled through a catabolic modulator factor, and r
p decreases.
Received: 8 September 1997 / Received last revision: 31 December 1997 / Accepted: 2 January 1998 相似文献
10.
I. Faus C. del Moral N. Adroer J. L. del Río C. Patiño H. Sisniega C. Casas J. Bladé V. Rubio 《Applied microbiology and biotechnology》1998,49(4):393-398
A recombinant form of the sweet-tasting protein thaumatin has been produced in the filamentous fungus Aspergillus niger var. awamori. Expression cassettes containing a synthetic gene encoding thaumatin II were prepared and used to transform Aspergillus niger var. awamori strain NRRL312. Several fungal strains capable of synthesizing and secreting thaumatin into the culture medium were generated,
and their production capabilities were determined, first in shake flasks and later in a laboratory fermentor. We report the
expression and secretion of thaumatin in concentrations of 5–7 mg/l. This recombinant thaumatin is sweet.
Received: 7 October 1997 / Received revision: 21 November 1997 / Accepted: 21 November 1997 相似文献
11.
M. Kunioka 《Applied microbiology and biotechnology》1997,47(5):469-475
The biosynthesis and chemical reactions of poly(amino acid)s produced by microorganisms are reviewed. A large amount of γ-poly(glutamic
acid) (PGA) has been produced by Bacillus strains. ε-Polylysine (PL) has been produced by Streptomyces albulus. As a modification of PGA and PL, pH-sensitive hydrogels have been prepared by means of γ irradiation or the addition of
a crosslinking agent to an aqueous solution of PGA and PL.
Received: 4 September 1996 / Received revision: 27 January 1997 / Accepted: 28 January 1997 相似文献
12.
P. Schmitt C. Vasseur V. Phalip D. Q. Huang C. Diviès H. Prévost 《Applied microbiology and biotechnology》1997,47(6):715-718
The co-metabolism of citrate plus xylose by Leuconostoc mesenteroides subsp. mesenteroides results in a growth stimulation, an increase in d-lactate and acetate production and repression of ethanol production. This correlated well with the levels of key enzymes
involved. A partial repression of alcohol dehydrogenase and a marked stimulation of acetate kinase were observed. High citrate
bioconversion yields in diacetyl plus acetoin were obtained at pH 5.2 in batch (11.5%) or in chemostat (up to 17.4%) culture.
In contrast, no diacetyl or acetoin was detected in citrate plus glucose fermentation.
Received: 6 December 1996 / Received revision: 14 February 1997 / Accepted: 14 February 1997 相似文献
13.
D. Segura C. Santana R. Gosh L. Escalante S. Sanchez 《Applied microbiology and biotechnology》1997,48(5):615-620
In Streptomyces peucetius var. caesius, the production of anthracyclines was suppressed either by 330 mM d-glucose or 25 mM phosphate. In addition, the anthracycline doxorubicin and the glucose analogue 2-deoxyglucose inhibited
the growth of this microorganism at concentrations of 0.025 mM and 10 mM respectively. Spontaneous and induced mutants, resistant
to the action of these compounds, were isolated, tested and chosen by their ability to overproduce anthracyclines. Genetic
recombination between representative mutants was carried out by the protoplast fusion technique. Some recombinants carrying
resistance to doxorubicin, phosphate and 2-deoxyglucose produced more than 40-fold greater levels of anthracyclines than those
obtained with the parental strain. This improvement resulted in total antibiotic titres of more than 2 g/l culture medium
at 6 days of fermentation.
Received: 14 April 1997 / Received revision: 19 June 1997 / Accepted: 4 July 1997 相似文献
14.
D. Stassi D. Post M. Satter M. Jackson G. Maine 《Applied microbiology and biotechnology》1998,49(6):725-731
The erythromycin producer, Saccharopolyspora erythraea ER720, was genetically engineered to produce 6,12-dideoxyerythromycin A, a novel erythromycin derivative, as the major macrolide
in the fermentation broth. Inspection of the biosynthetic pathway for erythromycin would suggest that production of this compound
could be achieved simply through the disruption of two genes, that encoding the erythromycin C-6 hydroxylase (eryF ) and that encoding the erythromycin C-12 hydroxylase (eryK ). The double mutant, however, was found to produce a mixture of 6,12-dideoxyerythromycin A and the precursor, 6-deoxyerythromycin
D. Complete conversion to the desired product (to the limit of detection by TLC) was achieved by inserting an additional copy
of the eryG gene, encoding the erythromycin 3′′-O-methyltransferase and driven by the ermE* promoter, into the S. erythraea chromosome.
Received: 6 October 1997 / Received revision: 27 January 1998 / Accepted: 24 February 1998 相似文献
15.
Thiobacillus ferrooxidans was able to grow under anaerobic conditions on copper sulphide with ferric ion as the electron acceptor. The dissolution of
covellite under these conditions (68% after 35 days) was higher than values observed aerobically in cultures with similar
media composition and almost as high as under aerobic conditions without iron. From these results we propose a mechanism for
anaerobic bioleaching of covellite in the presence of ferric iron and speculate that it may occur in leach dumps where the
oxygen concentration is, as reported elsewhere, very low.
Received: 3 September 1996 / Received revision: 13 January 1997 / Accepted: 24 January 1997 相似文献
16.
T. Ohshiro M. Shinji Y. Morita Y. Takayama Y. Izumi 《Applied microbiology and biotechnology》1997,48(4):546-548
Microorganisms capable of cleaving the urethane bond of t-butoxycarbonyl (Boc) amino acids in a whole-cell reaction were screened among stock cultures, and Corynebacterium aquaticum IFO12154 was the most promising. The conversion of Boc-Ala to Ala was stimulated by CoSO4 in the medium and reaction mixture. The optimum whole-cell concentration was 25 mg lyophilized cells/ml. Boc-l-Met was the best substrate for this reaction, and other Boc-L-amino acids, as well as benzyloxycarbonyl-l-amino acids with hydrophobic residues, were also good substrates. Boc-d- and Z-d-amino acids were inert. When the reactions had proceeded for 24 h with each substrate at 10 mM, the molar conversion rates
from Boc-l-, dl- and d-Met were 100%, 50%, and 0% respectively. From 150 mM Boc-l-Met, 143 mM l-Met was formed at a molar yield of 95.3%.
Received: 3 September 1996 / Received last revision: 7 April 1997 / Accepted: 19 April 1997 相似文献
17.
P. Arvidsson K. Nilsson H. Håkanson B. Mattiasson 《Applied microbiology and biotechnology》1998,49(6):677-681
A chemiluminescence detector was used to measure the production of nitric oxide, NO, from the denitrifying bacteria Pseudomonas stutzeri. NO is an intermediate when P. stutzeri converts nitrate into nitrogen gas. The reaction between NO and ozone is selective and sensitive in generating chemiluminescence.
Calibrations were made down to 1 nM, with a signal-to-noise ratio of 3. Bacteria were immobilised in alginate beads. Denitrification
experiments were made in an anaerobic non-growth medium by adding nitrate to a certain concentration in the reactor. The bacteria
were exposed to nitrate in the concentration range 1 pM–5 mM. The lowest concentration to give a measurable NO response was
100 nM.
Received: 16 October 1997 / Received revision: 20 January 1998 / Accepted: 24 January 1998 相似文献
18.
Hydrogen production with high yield and high evolution rate by self-flocculated cells of Enterobacter aerogenes in a packed-bed reactor 总被引:6,自引:1,他引:5
M. A. Rachman Y. Nakashimada T. Kakizono N. Nishio 《Applied microbiology and biotechnology》1998,49(4):450-454
Continuous hydrogen gas evolution by self-flocculated cells of Enterobacter aerogenes, a natural isolate HU-101 and its mutant AY-2, was performed in a packed-bed reactor under glucose-limiting conditions in
a minimal medium. The flocs that formed during the continuous culture were retained even when the dilution rate was increased
to 0.9 h−1. The H2 production rate increased linearly with increases in the dilution rate up to 0.67 h−1, giving maximum H2 production rates of 31 and 58 mmol l−1 h−1 in HU-101 and AY-2 respectively, at a dilution rate of more than 0.67 h−1. The molar H2 yield from glucose in AY-2 was maintained at about 1.1 at dilution rates between 0.08 h−1 and 0.67 h−1, but it decreased rapidly at dilution rates more than 0.8 h−1.
Received: 27 August 1997 / Received revision: 11 November 1997 / Accepted: 14 December 1997 相似文献
19.
Yang-Ming Lo Shang-Tian Yang David B. Min 《Applied microbiology and biotechnology》1997,47(6):689-694
Although available kinetic data provide a useful insight into the effects of medium composition on xanthan production by
Xanthomonas campestris, they cannot account for the synergetic effects of carbon (glucose) and nitrogen (yeast extract) substrates on cell growth
and xanthan production. In this work, we studied the effects of the glucose/yeast-extract ratio (G/YE) in the medium on cell
growth and xanthan production in various operating modes, including batch, two-stage batch, and fed-batch fermentations. In
general, both the xanthan yield and specific production rate increased with increasing G/YE in the medium, but the cell yield
and specific growth rate decreased as G/YE increased. A two-stage batch fermentation with a G/YE shift from an initial low
level (2.5% glucose/0.3% yeast extract) to a high level (5.0% glucose/0.3% yeast extract) at the end of the exponential growth
phase was found to be preferable for xanthan production. This two-stage fermentation design both provided fast cell growth
and gave a high xanthan yield and xanthan production rate. In contrast, fed-batch fermentation with intermittent additions
of glucose to the fermentor during the stationary phase was not favorable for xanthan production because of the relatively
low G/YE resulting in low xanthan production rate and yield. It is also important to use a moderately high yeast extract concentration
in the medium in order to reach a high cell density before the culture enters the stationary phase. A high cell density is
also important to the overall xanthan production rate.
Received: 30 September 1996 / Received revision: 21 January 1997 / Accepted: 10 February 1997 相似文献
20.
Production of high yields of arachidonic acid in a fed-batch system by Mortierella alpina ATCC 32222
Of six strains of Mortierella tested, Mortierella alpina ATCC 32222 produced the highest yields of arachidonic acid. Supplementation of soy flour (1% w/v) and vegetable oils (1%
v/v) significantly increased the biomass, lipid content and arachidonic acid level. Replacement of NaNO3 with corn steep liquor (1% w/v) also improved arachidonic acid production. A fed-batch culture system at 25 °C, producing
a high biomass (52.4 g/l) and arachidonic acid content (9.1 g/l) in 8␣days, was developed. A fed-batch system at low temperature
(15 °C) gave even higher arachidonic acid levels (11.1 g/l) in 11 days.
Received: 28 October 1996 / Received revision: 3 March 1997 / Accepted: 7 March 1997 相似文献