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1.
Vargas-García MC López MJ Elorrieta MA Suárez F Moreno J 《Journal of industrial microbiology & biotechnology》2002,29(3):129-133
The relationship between exopolysaccharide (EPS) production by Azotobacter vinelandii ATCC 12837 from 4-hydroxybenzoic acid as sole carbon source and other physiological parameters was investigated. In relation
to growth, Azotobacter needed more time in 4-hydroxybenzoic acid to reach levels of biomass similar to those obtained when sugars were used, although
the phenolic compound led to a more extensive exponential phase. The encystment process was initiated after cells had grown
for 24 h, in which small amounts of EPS were synthesized and poly-β-hydroxybutyrate (PHB) accumulation began. Both polymers,
EPS and PHB, showed a similar evolution with time, as well as the formation of cysts, which points out the existence of a
relation between these parameters. This was corroborated by a statistical study, in which significant correlations (P<0.05) were observed when each parameter was compared to the two others. Journal of Industrial Microbiology & Biotechnology (2002) 29, 129–133 doi:10.1038/sj.jim.7000288
Received 01 February 2002/ Accepted in revised form 13 June 2002 相似文献
2.
Effects of acetic acid and lactic acid on the growth of Saccharomyces cerevisiae in a minimal medium 总被引:1,自引:0,他引:1
N V Narendranath K C Thomas W M Ingledew 《Journal of industrial microbiology & biotechnology》2001,26(3):171-177
Specific growth rates (μ) of two strains of Saccharomyces cerevisiae decreased exponentially (R
2>0.9) as the concentrations of acetic acid or lactic acid were increased in minimal media at 30°C. Moreover, the length of
the lag phase of each growth curve (h) increased exponentially as increasing concentrations of acetic or lactic acid were
added to the media. The minimum inhibitory concentration (MIC) of acetic acid for yeast growth was 0.6% w/v (100 mM) and that
of lactic acid was 2.5% w/v (278 mM) for both strains of yeast. However, acetic acid at concentrations as low as 0.05–0.1%
w/v and lactic acid at concentrations of 0.2–0.8% w/v begin to stress the yeasts as seen by reduced growth rates and decreased
rates of glucose consumption and ethanol production as the concentration of acetic or lactic acid in the media was raised.
In the presence of increasing acetic acid, all the glucose in the medium was eventually consumed even though the rates of
consumption differed. However, this was not observed in the presence of increasing lactic acid where glucose consumption was
extremely protracted even at a concentration of 0.6% w/v (66 mM). A response surface central composite design was used to
evaluate the interaction between acetic and lactic acids on the specific growth rate of both yeast strains at 30C. The data
were analysed using the General Linear Models (GLM) procedure. From the analysis, the interaction between acetic acid and
lactic acid was statistically significant (P≤0.001), i.e., the inhibitory effect of the two acids present together in a medium is highly synergistic. Journal of Industrial Microbiology & Biotechnology (2001) 26, 171–177.
Received 06 June 2000/ Accepted in revised form 21 September 2000 相似文献
3.
Exopolysaccharide (EPS) production was compared among three strains of lactobacilli. Lactobacillus rhamnosus strain 9595M can be classified among the highest EPS-producing strains of lactic acid bacteria reported to date with a maximum
EPS production of 1275 mg L−1. Under controlled pH, no significant differences in the quantity of EPS produced could be detected between carbon source
(glucose or lactose) or fermentation temperature (32 or 37°C). In milk, strains ATCC 9595M and R produced more than 280 mg L−1 EPS whereas strain Type V produced less than 80 mg L−1 EPS. Journal of Industrial Microbiology & Biotechnology (2000) 24, 251–255.
Received 10 September 1999/ Accepted in revised form 22 December 1999 相似文献
4.
V. I. Elisashvili E. T. Kachlishvili S. P. Wasser 《Applied Biochemistry and Microbiology》2009,45(5):531-535
The capability to synthesize the extracellular polysaccharide (EPS) is widespread among eight mushroom species which accumulated 0.6–2.2 g/1 of EPS in submerged cultivation. Glucose, maltose,
and mannitol were the most appropriate carbon sources for biomass and EPS production. Organic nitrogen sources appeared to
be the most suitable nitrogen sources for biomass and EPS accumulation. The cultivation process in shake flasks was successfully
reproduced in a laboratory fermentor with enhanced EPS production. The highest yield of EPS (3.8–4.0 g/1) was achieved in
cultivation of Agaricus nevoi and Inonotus levis. 相似文献
5.
Microbial treatment of a styrene-contaminated air stream in a biofilter with high elimination capacities 总被引:3,自引:0,他引:3
A styrene-utilizing mixed microbial culture was isolated and utilized in a biofilter for the biological treatment of a contaminated
air stream. Biofilter media consisted of composted wood bark and yard waste. The biofilters were acclimated at 120 s residence
time and further evaluated at 60 and 30 s gas residence times. The biofilters received organic loading rates of up to 350
g/m3 h. The styrene volumetric removal rate was a function of the organic loading rate and increased with increasing loading rates.
Average volumetric removal rates of 69–118 g/m3 h observed in our studies were higher than reported values for styrene biofilters. Average styrene removal efficiencies ranged
from 65% to 75% (maximum 100%). Axial analysis of styrene concentration along the column indicated that the bulk of the styrene
removal occurred in the first section of the biofilter. Analyses of the media indicated that the moisture content of the first
section (50–55% w/w) was significantly lower than in the second and third sections (65–70% w/w). The pressure drops across
the biofilter were low due to the high concentration of large media particles. The total pressure drops were 1–3, 4–6, and
10–16 mm for the 120-, 60-, and 30-s residence time periods, respectively. Journal of Industrial Microbiology & Biotechnology (2001) 26, 196–202.
Received 04 March 2000/ Accepted in revised form 25 January 2001 相似文献
6.
V Calvente M E de Orellano G Sansone D Benuzzi M I Sanz de Tosetti 《Journal of industrial microbiology & biotechnology》2001,26(4):226-229
The production of rhodotorulic acid, a siderophore synthesized by Rhodotorula strains, was improved with the objective of achieving the biocontrol of phytopathogenic moulds. Rhodotorulic acid increased
up to 60% in the presence of urea as a nitrogen source, pH near to 8 and a C:N ratio of 8:1. The siderophore-containing spent
medium showed in vitro antifungal activity against important plant pathogens including Botrytis cinerea, which causes grey mould on a wide variety of host plants including numerous commercial crops. The antifungal activity was
related to siderophore concentration. Journal of Industrial Microbiology & Biotechnology (2001) 26, 226–229.
Received 06 June 2000/ Accepted in revised form 28 January 2001 相似文献
7.
The influencing factors of extracellular polysaccharide (EPS) produced from a strain of lactic acid bacteria (LAB L15) were
studied by using the phenol-H2SO4 method. It was demonstrated that the strain produced EPS at the most amount when it was incubated for 40–48 h and when the
pH value was 4 under 30°C. Glucose was the most suitable carbon source for LAB-producing EPS. The rough EPS was obtained from
L15 culture after centrifugation, dialysis, deprotein, decoloration, and ethanol-precipitation. The sample was at least composed
of two polysaccharides that were completely different in molecular weight and the amount. The purified EPS was passed through
the SephadexG-200 column and it showed that it was a sample purified by thin layer chromatography.
__________
Translated from Microbiology, 2005, 32(4): 85–90 [译自: 微生物学通报, 2005, 32(4): 85–90] 相似文献
8.
Increased erythritol production in fed-batch cultures of Torula sp. by controlling glucose concentration 总被引:2,自引:0,他引:2
D-K Oh C-H Cho J-K Lee S-Y Kim 《Journal of industrial microbiology & biotechnology》2001,26(4):248-252
The effect of glucose concentration on erythritol production by Torula sp. was investigated. The maximum volumetric productivity of erythritol was obtained at an initial glucose concentration
of 300 g l−1 in batch culture. The volumetric productivity was maximal at a controlled glucose concentration of 225 g l−1, reducing the lag time of the erythritol production. A fed-batch culture was established with an initial glucose concentration
of 300 g l−1 and with a controlled glucose concentration of 225 g l−1 in medium containing phytic acid as a phosphate source. In this fed-batch culture, a final erythritol production of 192 g
l−1 was obtained from 400 g l−1 glucose in 88 h. This corresponded to a volumetric productivity of 2.26 g l−1 h−1 and a 48% yield. Journal of Industrial Microbiology & Biotechnology (2001) 26, 248–252.
Received 26 September 2000/ Accepted in revised form 16 January 2001 相似文献
9.
The effect of inorganic phosphate on the biosynthesis of nebramycin factors2, 4 and5′ was studied inStreptomyces tenebrarius strain A (forming2, 4 and5′ in natural ratios) and its mutants B (forming predominantly2), C (forming2 as the only major product) and D (forming predominantly5′). In phosphate-supplemented complex media, the production of2 in A, B and C was reduced by 20–70%, while the yields of5′ remained unchanged in A and decreased by 30–60% in B. The production of4 increased by 50–90% in A and was fully suppressed in B. In D the biosynthesis of the three factors was inhibited completely. 相似文献
10.
Modulation of epothilone analog production through media design 总被引:1,自引:0,他引:1
Frykman S Tsuruta H Lau J Regentin R Ou S Reeves C Carney J Santi D Licari P 《Journal of industrial microbiology & biotechnology》2002,28(1):17-20
Recently, the epothilone polyketide synthase (PKS) was successfully introduced into a heterologous production host for the
large-scale production of epothilone D. We have found that at least three other epothilones can also be produced as the major
fermentation product of this recombinant strain by supplementation of specific substrates to the production media. Addition
of acetate or propionate to the media results in modulation of the epothilone D:C ratio, whereas addition of l-serine with either acetate or propionate yields epothilone H1 or H2 as the major product. This strategy permits production of at least four novel epothilones by culturing a single host with
a genetically modified epothilone PKS in various media. Journal of Industrial Microbiology & Biotechnology (2002) 28, 17–20 DOI: 10.1038/sj/jim/7000209
Received 20 June 2001/ Accepted in revised form 03 September 2001 相似文献
11.
von Weymarn N Kiviharju K Leisola M 《Journal of industrial microbiology & biotechnology》2002,29(1):44-49
Ten heterofermentative lactic acid bacteria were compared in their ability to produce D-mannitol from D-fructose in a resting state. The best strain, Leuconostoc mesenteroides ATCC-9135, was examined in high cell density membrane cell-recycle cultures. High volumetric mannitol productivity (26.2
g l−1 h−1) and mannitol yield (97 mol%) were achieved. Using the same initial biomass, a stable high-level production of mannitol was
maintained for 14 successive bioconversion batches. Applying response surface methodology, the temperature and pH were studied
with respect to specific mannitol productivity and yield. Moreover, increasing the initial fructose concentration from 100
to 120 and 140 g l−1 resulted in decreased productivities due to both substrate and end-product inhibition of the key enzyme, mannitol dehydrogenase
(MDH). Nitrogen gas flushing of the bioconversion media was unnecessary, since it did not change the essential process parameters.
Journal of Industrial Microbiology & Biotechnology (2002) 29, 44–49 doi:10.1038/sj.jim.7000262
Received 12 November 2001/ Accepted in revised form 30 March 2002 相似文献
12.
T. Yokochi D. Honda T. Higashihara T. Nakahara 《Applied microbiology and biotechnology》1998,49(1):72-76
Culture conditions of Schizochytrium limacinum SR21 for the purpose of microbial docosahexaenoic acid (DHA) production were investigated. The strain SR21 showed a wide
tolerance to salinity; that is, the optimum salinity was between 50% and 200% that of sea water. Monosaccharides (glucose
and fructose) and glycerol supported good cell growth and DHA yield. Di- and polysaccharides, oleic acid, and linseed oil
gave low DHA yields. A high content of DHA (more than 30% of total fatty acids) was obtained from culture on glucose, fructose,
and glycerol, and also the strain had simple polyunsaturated fatty acid profiles. The major polyunsaturated fatty acids other
than DHA were n-6 docosapentaenoic acid only, and the contents of icosapentaenoic acid and arachidonic acid were less than 1%. Using corn
steep liquor as a nitrogen source, a high total fatty acid content was obtained. The total fatty acid content in the dry cell
weight increased as the concentration of the nitrogen source decreased, reached more than 50%. An increase in carbon source
concentration led to a high DHA yield. A maximum DHA yield of more than 4 g/l was obtained in both glucose and glycerol media
at 9% and 12% respectively. S. limacinum SR21 was thought to be a promising resource for microbial DHA production yielding a good level of productivity as well as
a simple polyunsaturated fatty acid profile.
Received: 26 June 1997 / Received revision: 29 August 1997 / Accepted: 19 September 1997 相似文献
13.
De Baets S Du Laing S François C Vandamme EJ 《Journal of industrial microbiology & biotechnology》2002,29(4):181-184
In liquid culture conditions, the yeast-like fungus Tremella mesenterica occurs in the yeast state and synthesizes an exopolysaccharide (EPS) capsule, which is eventually released into the culture
fluid. It is composed of an α-1,3-D-mannan backbone, to which β-1,2 side chains are attached, consisting of D-xylose and D-glucuronic acid. Potato dextrose broth (PDB) seemed to be an excellent medium for both growth of the yeast cells and synthesis
of the EPS. This medium is composed solely of an extract of potatoes to which glucose was added. Yet an important disadvantage
of this production medium is the presence of starch in the potato extract, since Tremella cells are not capable of metabolizing this component; furthermore, it coprecipitates upon isolation of the polymer [3]. In
this respect, it was essential to remove the starch in order to achieve high polysaccharide production and recovery. A good
method was the removal of starch through ultrafiltration of the PDB medium before inoculation of the strain. This resulted
in an excellent starch-free medium in which other components essential for polysaccharide production were still present [3].
Through implementation of single and cyclic fed-batch fermentations with glucose feed, 1.6- and 2.2-fold increases in EPS
yield were obtained, respectively. Lowering the carbon source level by using a cyclic fed-batch technique might decrease the
osmotic effect of glucose or any catabolite regulation possibly exerted by this sugar on enzymes involved in EPS synthesis.
Journal of Industrial Microbiology & Biotechnology (2002) 29, 181–184 doi:10.1038/sj.jim.7000276
Received 18 March 2002/ Accepted in revised form 20 May 2002 相似文献
14.
Several wild strains and mutants of Rhodotorula spp. were screened for growth, carotenoid production and the proportion of -carotene produced in sugarcane molasses. A better
producer, Rhodotorula glutinis mutant 32, was optimized for carotenoid production with respect to total reducing sugar (TRS) concentration and pH. In shake
flasks, when molasses was used as the sole nutrient medium with 40 g l−1 TRS, at pH 6, the carotenoid yield was 14 mg l−1 and -carotene accounted for 70% of the total carotenoids. In a 14-l stirred tank fermenter, a 20% increase in torulene content
was observed in plain molasses medium. However, by addition of yeast extract, this effect was reversed and a 31% increase
in -carotene content was observed. Dissolved oxygen (DO) stat fed-batch cultivation of mutant 32 in plain molasses medium
yielded 71 and 185 mg l−1 total carotenoids in double- and triple-strength medium, respectively. When supplemented with yeast extract, the yields were
97 and 183 mg l−1 total carotenoid with a 30% increase in -carotene and a simultaneous 40% decrease in torulene proportion. Higher cell mass
was also achieved by double- and triple-strength fed-batch fermentation. Journal of Industrial Microbiology & Biotechnology (2001) 26, 327–332.
Received 18 September 2000/ Accepted in revised form 02 March 2001 相似文献
15.
Filipa M. Lupi Helena M. L Fernandes Isabel Sá-Correia Júlio M. Novais 《Journal of applied phycology》1991,3(1):35-42
Temperature profiles (range 20–33 °C) were obtained for growth and exopolysaccharide (EPS) biosynthesis of the microalga Botryococcus braunii strain UC 58 under photoautotrophic conditions. The maximum temperature for growth was 32 °C and the temperature dependence
of the specific growth rate was described by the Hinshelwood equation based on the Arrhenius relationship. The optimal range
of temperatures for growth and extracellular EPS synthesis (25–30 °C) concurred and production of 4.5–5 g l−1 of EPS was obtained routinely, leading to high broth viscosities. Below 23 °C EPS biosynthesis was negligible, although the
specific growth rate maintained high values. At supraoptimal temperatures EPS biosynthesis decreased, accompanying the increase
in doubling time.
The polymers formed at temperatures within the optimal range for production, when dissolved in water, produced solutions (2
gl−1) with the highest viscosity, suggesting that their molecular weight showed the highest values. The degree of polymerization
of the EPS synthesized at suboptimal and supraoptimal temperatures was significantly below the values within the optimal range. 相似文献
16.
A. P. A. Tavares M. S. M. Agapito M. A. M. Coelho J. A. Lopes da Silva A. Barros-Timmons J. A. J. Coutinho A. M. R. B. Xavier 《World journal of microbiology & biotechnology》2005,21(8-9):1499-1507
Summary Coriolus versicolor is a medicinal fungus producing exopolysaccharides (EPS). Five well-defined culture media were studied to select the medium
that maximizes production of EPS by C. versicolor. Biomass, reducing sugars and EPS concentrations along with the rheological behaviour of the broth were followed during fermentations
lasting 9 days. The yeast malt extract medium (YM) was shown to yield the highest production of EPS. Fermentation conditions
with YM medium were further investigated to optimize EPS production by C. versicolor. An experimental design to do this was adopted, in which the effects of pH and initial substrate concentration were considered.
The effects of initial glucose concentration (5, 15 and 25 g l−1) and pH (4.0, 5.5 and 7.0) were evaluated. The initial glucose concentration was found to be the most important factor in
EPS production and also cell growth. 相似文献
17.
The biochemical kinetic of direct fermentation for lactic acid production by fungal species of Rhizopus arrhizus 3,6017 and Rhizopus oryzae 2,062 was studied with respect to growth pH, temperature and substrate. The direct fermentation was characterized by starch
hydrolysis, accumulation of reducing sugar, and production of lactic acid and fungal biomass. Starch hydrolysis, reducing
sugar accumulation, biomass formation and lactic acid production were affected with the variations in pH, temperature, and
starch source and concentration. A growth condition with starch concentration approximately 20 g/l at pH 6.0 and 30°C was
favourable for both starch saccharification and lactic acid fermentation, resulting in lactic acid yield of 0.87–0.97 g/g
starch associated with 1.5–2.0 g/l fungal biomass produced in 36 h fermentation. R. arrhizus 3,6017 had a higher capacity to produce lactic acid, while R. oryzae 2,062 produced more fungal biomass under similar conditions. 相似文献
18.
Summary The effects of components of the medium on the production of extracellular polysaccharide (EPS) by cultured cells of Polianthes tuberosa (tuberose) were studied. Optimization of media components culturing in flask resulted in increasing EPS production from 1.4 to 4.1 g/l. In particular, relatively high concentration (10\s-5M) of 2,4-dichlorophenoxyacetic acid (2,4-D) markedly stimulated the production of EPS. Based on these results, EPS production by a 30-1 jar fermenter was attempted and the final rate of Production was 4.6 g/l at 30th day of culture. The EPS consisted mainly of acidic polysaccharides with glucuronic acid, mannose, arabinose, galactose, glucose and xylose. 相似文献
19.
No increases in exopolysaccharide (EPS) yields in Aureobasidium pullulans were observed when grown with reduced-shear impellers instead of standard Rushton turbines in the same vessel. However, yields
were dramatically reduced when the organism was grown in an airlift reactor. This fall in production could be counteracted
by improving fluid circulation through the placement of impellers within the draught tube, a strategy that resulted in the
highest EPS concentration (approx. 13 g l−1) of all the fermenter configurations tested.
Received: 24 June 1997 / Revised revision: 25 September 1997 / Accepted: 29 September 1997 相似文献
20.
Kinetic analysis on formation of poly(3-hydroxybutyrate) from acetic acid by Ralstonia eutropha under chemically defined conditions 总被引:1,自引:0,他引:1
Batch cultures of Ralstonia eutropha in chemically defined media with acetic acid (HAc) as the sole carbon source were conducted to investigate acetate utilization,
formation of poly(3-hydroxybutyrate) (PHB) and growth of active biomass (ABM) under different carbon to nitrogen (C/N) weight
ratios. The specific acetate utilization rate based on ABM approached 0.16 g/g ABM h−1, which was not affected very much by the extracellular HAc concentration from 1 to 5 g/l, but was affected by the C/N weight
ratio. A low C/N ratio or high nitrogen supply sped up the specific acetate utilization rate to produce more ABM and less
PHB. A high HAc concentration (>6 g/l), however, depressed acetate utilization as well as the ABM growth and PHB formation.
A high cell mass concentration enhanced the tolerance of R. eutropha to the toxicity of HAc at pH 7 to 8.5. The viscosity-average molecular size of PHB generally increased first and then declined
in batch cultures. Larger PHB molecules and less PHB per ABM were produced at a low C/N ratio with enough nutrient nitrogen
than those under a high C/N ratio with less nutrient nitrogen available. Journal of Industrial Microbiology & Biotechnology (2001) 26, 121–126.
Received 06 June 2000/ Accepted in revised form 21 October 2000 相似文献