共查询到20条相似文献,搜索用时 15 毫秒
1.
G. Misra S. G. Pavlostathis E. M. Perdue R. Araujo 《Applied microbiology and biotechnology》1996,45(6):831-838
Batch experiments were conducted to assess the biotransformation potential of four hydrocarbon monoterpenes (d-limonene, α-pinene, γ-terpinene, and terpinolene) and four alcohols (arbanol, linalool, plinol, and α-terpineol) under aerobic
conditions at 23°C. Both forest-soil extract and enriched cultures were used as inocula for the biodegradation experiments
conducted first without, then with prior microbial acclimation to the monoterpenes tested. All four hydrocarbons and two alcohols
were readily degraded. The increase in biomass and headspace CO2 concentrations paralleled the depletion of monoterpenes, thus confirming that terpene disappearance was the result of biodegradation
accompanied by microbial growth and mineralization. Plinol resisted degradation in assays using inocula from diverse sources,
while arbanol degraded very slowly. A significant fraction of d-limonene-derived carbon was accounted for as non-extractable, dissolved organic carbon, whereas terpineol exhibited a much
higher degree of utilization. The rate and extent of monoterpene biodegradation were not significantly affected by the presence
of dissolved natural organic matter.
Received: 27 November 1995/Received last revision: 15 March 1996/Accepted: 17 March 1996 相似文献
2.
F. Eismann F. Becker P. Kuschk U. Stottmeister 《Applied microbiology and biotechnology》1996,46(5-6):604-609
Biotreatment experiments with solutions of autoxidized phenolic compounds as well as coal-conversion wastewater stored for
30 years and rich in humic matter were performed under nitrate-reducing, sulphate-reducing and methanogenic conditions. The
removal of total organic carbon in fractions of different molecular mass and of monomeric phenolic compounds in the wastewater
was determined. A comparison of biotransformation potentials and rates indicated a relationship between these aspects and
the availability of electron acceptors in the system. The capacities of the microbial consortia increased significantly with
the energy microorganisms could gain from their respective respiration process and can be expressed by the order: aerobic
process – nitrate reduction – sulphate reduction – methanogenesis.
Received: 25 April 1996 / Received revision: 23 July 1996 / Accepted: 5 August 1996. 相似文献
3.
Batch experiments were conducted to evaluate the biodegradation rates of limonene, α-pinene, γ-terpinene, terpinolene and
α-terpineol at 23 °C under aerobic conditions. Biodegradation was demonstrated by the depletion of monoterpene mass, CO2 production and a corresponding increase in biomass. Monoterpene degradation in liquid cultures devoid of soil followed Monod
kinetics. The maximum specific growth rate (μmax) was 0.02 h−1 and 0.06 h−1 and the half-velocity constant (K
s ) varied from 32 mg/l to 3 mg/l for the limonene and α-terpineol respectively. The recovery of monoterpenes by solvent extraction
from autoclaved and azide-amended soil-slurry samples decreased over time and ranged from 69% to 73% for 120 h of incubation
period. Although a significant fraction of monoterpene hydrocarbon could not be extracted, mineralization of these compounds
in the soil-slurry systems took place, as shown by CO2 production. The soil-normalized degradation rates for the hydrocarbon monoterpenes ranged from 0.6 μg g−1 h−1 to 2.1 μg g−1 h−1. A kinetic model – which combined monoterpene biodegradation in the liquid phase and net desorption – was developed and applied
to data obtained from soil-slurry assays.
Received: 10 September 1996 / Received revision: 16 December 1996 / Accepted: 10 January 1997 相似文献
4.
Chernyavskaya OG Shishkanova NV Il'chenko AP Finogenova TV 《Applied microbiology and biotechnology》2000,53(2):152-158
The ability of yeast to synthesize α-ketoglutaric acid (KGA) from ethanol has been studied. Thiamine-auxotrophic yeasts of
different genera and species may be able to produce KGA; the main condition of synthesis is growth limitation by thiamine.
Using a model culture, mutant Yarrowia lipolytica N 1, the principal conditions affecting KGA oversynthesis were identified. These were: thiamine concentration in medium and
in cells, nitrogen and oxygen concentration in medium, and pH level. A KGA concentration of 49 g/l and a yield from ethanol
consumed of 42% were achieved. Based on the results of the analysis of the activities of the key enzymes participating in
ethanol metabolism and KGA synthesis, a concept of the mechanism of KGA biosynthesis by Y. lipolytica yeast is suggested and discussed.
Received: 1 March 1999 / Received revision: 28 June 1999 / Accepted: 5 June 1999 相似文献
5.
M. Shepherd J. X. Chaparro R. Teasdale 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1999,99(7-8):1207-1215
Genetic control of foliar oil composition was investigated amongst half-sib progeny of an interspecific eucalypt hybrid. The
oil was found to be largely composed of the monoterpenes, limonene, α−pinene, γ−terpinene, 1,8 cineole and p-cymene. Due to difficulties in the interpretation of the compositional data based on raw proportions, further analysis was
conducted using log-ratio variables. A high degree of intercorrelation amongst log-ratios was thought to be a consequence
of commonality in the biosynthetic origins of the monoterpenes. Quantitative trait locus (QTL) analysis of log-ratio variables
indicated that a significant (68–81%) proportion of the variation in four out of the ten possible log-ratios were controlled
by a single genomic region of the maternal Eucalyptus
grandis parent. The impact of this genomic region upon oil composition was thought to be a consequence of a gene, or genes, controlling
the production of limonene, as limonene was the predominant oil constituent in many hybrid individuals and was common to all
log-ratios associated with the identified genomic region.
Received: 20 November 1998 / Accepted: 16 June 1999 相似文献
6.
Extracts from brown seaweeds could possibly be fermented to ethanol, particularly seaweeds harvested in the autumn, which
contain high levels of easily extractable laminaran and mannitol. Few microorganisms are able to utilise mannitol as a substrate
for ethanol production and Zymobacter palmae was tested for this purpose. Bacterial growth as well as ethanol yield depended on the amount of oxygen present. Strictly
anaerobic growth on mannitol was not observed. At excessive aeration, a change in the fermentation pattern was observed with
high production of acetate and propionate. Under oxygen-limiting conditions, the bacteria grew and produced ethanol in a synthetic
mannitol medium with a yield of 0.38 g ethanol (g mannitol)−1. Z. palmae was also successfully applied for fermentation of mannitol from Laminaria hyperborea extracts. Journal of Industrial Microbiology & Biotechnology (2000) 24, 51–57.
Received 27 June 1999/ Accepted in revised form 23 September 1999 相似文献
7.
Michael Pescheck Marco Antonio Mirata Bianca Brauer Ulrich Krings Ralf Günter Berger Jens Schrader 《Journal of industrial microbiology & biotechnology》2009,36(6):827-836
A closed gas loop bioprocess was developed to improve fungal biotransformation of monoterpenes. By circulating monoterpene-saturated
process gas, the evaporative loss of the volatile precursor from the medium during the biotransformation was avoided. Penicillium solitum, isolated from kiwi, turned out to be highly tolerant towards monoterpenes and to convert α-pinene to a range of products
including verbenone, a valuable aroma compound. The gas loop was mandatory to reproduce the production of 35 mg L−1 verbenone obtained in shake flasks and also in the bioreactor. Penicillium digitatum DSM 62840 regioselectively converted (+)-limonene to the aroma compound α-terpineol, but shake flask cultures revealed a
pronounced growth inhibition when initial concentrations exceeded 1.9 mM. In the bioreactor, toxic effects on P. digitatum during biotransformation were alleviated by starting a sequential feeding of non-toxic limonene portions after a preceding
growth phase. Closing the precursor-saturated gas loop during the biotransformation allowed for an additional replenishment
of limonene via the gas phase. The gas loop system led to a maximum α-terpineol concentration of 1,009 mg L−1 and an average productivity of 8–9 mg L−1 h−1 which represents a doubling of the respective values previously reported. Furthermore, a molar conversion yield of up to
63% was achieved.
M. Pescheck and M. A. Mirata have contributed equally to this work. 相似文献
8.
Furmanowa Mirosława Hartwich Małgorzata Alfermann August W. Koźmiński Wiktor Olejnik Marian 《Plant Cell, Tissue and Organ Culture》1999,56(2):105-110
The paper discusses glycosylation of trans-cinnamyl alcohol to obtain the biologically active compound rosavin and possibly
other cinnamoylglycosides. Cell suspension cultures of Rhodiola rosea were established from callus of leaf origin cultured
under light in a modified Murashige and Skoog medium. Under these conditions, no rosavin was formed. However, when trans-cinnamyl
alcohol (2.5 mM; in MeOH) was added to the medium, after 72 h incubation cells transformed over 90% of the cinnamyl alcohol
into a number of unidentified products. The structure of potential rosavin accumulated in intracellular spaces was elucidated
as [3-phenyl-2-propenyl-O-(6'-O-α-L-arabinopyranosyl) -β-D-glucopyranoside] by means of chemical and spectral analysis using
TLC, HPLC, UV, LSIMS and NMR methods. Rosavin yields of 0.03–1.01% dry weight were obtained. The actual amount depended on
the cell strain cultured and the biotransformation period.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
9.
The effect of chronic ethanol consumption on cerebral cortical activity of Na,K-ATPase was determined in Long-Evans (LE) rats
fed an ethanol-containing diet beginning at different stages of development. Na,K-ATPase activity was operationally resolved
into α1 and α2/3 isozyme activities. There was no significant difference in Na,K-ATPase activities before and after alcohol
consumption in the preparations from adult rats. However, for rats beginning alcohol consumption as adolescents, the α2/3
activity was significantly elevated following chronic alcohol consumption. Both LE and Sprague–Dawley rats showed this same
selective increase in cortical α2/3 activity when rats began alcohol consumption as juveniles. The shift in cortical α2/3
activity was not observed in cerebellum or subcortical forebrain and was reversible when rats were fed ethanol throughout
the normal adolescent period and then withdrawn and tested 2 weeks later (during the adult period). Levels of isoform-specific
mRNA were determined in preparations of cerebral cortices of rats showing elevated α2/3 isozyme activities. In these preparations,
isoform specific α2 and α3 mRNA was significantly elevated. There was no effect of ethanol feeding on cortical α1 mRNA. These
findings indicate that the longer term effects of ethanol on the developing brain include elevated Na,K-ATPase activity and
a mechanism that is pre-translational and isoform specific. 相似文献
10.
K C A Bromley-Challenor N Caggiano J S Knapp 《Journal of industrial microbiology & biotechnology》2000,25(1):8-16
The degradation of N,N-dimethylformamide (DMF) by bacterial consortia was investigated under aerobic, fermentative and nitrate-reducing conditions
and a variety of salt concentrations (0.2%, 4% and 7% NaCl w/v) and pH values (5 and 7). Optimization of degradation conditions
was studied to provide information and recommendations for large-scale biological treatment processes. Under aerobic conditions,
mineralization of DMF (200 mg l−1, 2.7 mM) was achieved under all combinations of salinity and pH. The rate of bacterial growth decreased with increasing salinity.
Changes in the salt concentration and pH still resulted in mineralization and unchanged yield of bacterial cells. At 0.2%
NaCl and either pH 5 or 7, growth occurred on DMF in the range 0.2–1 g l−1. However, cell yield decreased with increasing concentrations of DMF. Under conditions of 0.2% NaCl, pH 7 and 4% NaCl, pH
5, growth on DMF at 5 g l−1 resulted in the production of an intermediate that was detected using gas chromatography (GC). It is proposed that the intermediate
was dimethylamine, and its persistence in growth media was attributed to suppressed growth as a result of an increase in pH.
A culture capable of degrading DMF under nitrate-reducing conditions was obtained at 0.2% NaCl and pH 7, but not at more saline
and acidic conditions. Growth and degradation of DMF were considerably slower under these conditions compared with aerobic
conditions. Fermentative degradation of DMF was not observed. Journal of Industrial Microbiology & Biotechnology (2000) 25, 8–16.
Received 14 July 1999/ Accepted in revised form 30 March 2000 相似文献
11.
Kajiwara S Aritomi T Suga K Ohtaguchi K Kobayashi O 《Applied microbiology and biotechnology》2000,53(5):568-574
The fermentation characteristics of Saccharomyces cerevisiae strains which overexpress a constitutive OLE1 gene were studied to clarify the relationship between the fatty acid composition of this yeast and its ethanol productivity.
The growth yield and ethanol productivity of these strains in the medium containing 15% dextrose at 10 °C were greater than
those of the control strains under both aerobic and anaerobic conditions but this difference was not observed under other
culture conditions. During repeated-batch fermentation, moreover, the growth yield and ethanol productivity of the wild-type
S. cerevisiae increased gradually and then were similar to those of the OLE1-overexpressing transformant in the last batch fermentation. However, the unsaturated fatty acid content (77.6%) of the wild-type
cells was lower than that (86.2%) of the OLE1-recombinant cells. These results suggested that other phenomena caused by the overexpression of the OLE1 gene, rather than high unsaturated fatty acid content, are essential to ethanol fermentation by this yeast.
Received: 11 June 1999 / Received last revision: 12 November 1999 / Accepted: 28 November 1999 相似文献
12.
Anaerobic oxidation of the aromatic plant hydrocarbon p-cymene by newly isolated denitrifying bacteria 总被引:2,自引:0,他引:2
The capability of nitrate-reducing bacteria to degrade alkyltoluenes in the absence of molecular oxygen was investigated
with the three isomers of xylene, ethyltoluene, and isopropyltoluene (cymene) in enrichment cultures inoculated with freshwater
mud. Denitrifying enrichment cultures developed most readily (within 4 weeks) with p-cymene, a natural aromatic hydrocarbon occurring in plants, and with m-xylene (within 6 weeks). Enrichment of denitrifiers that utilized m-ethyltoluene and p-ethyltoluene was slow (within 8 and 12 weeks, respectively); no enrichment cultures were obtained with the other alkylbenzenes
within 6 months. Anaerobic degradation of p-cymene, which has not been reported before, was studied in more detail. Two new types of denitrifying bacteria with oval
cells, strains pCyN1 and pCyN2, were isolated; they grew on p-cymene (diluted in an inert carrier phase) and nitrate with doubling times of 12 and 16 h, respectively. Strain pCyN1, but
not strain pCyN2, also utilized p-ethyltoluene and toluene. Both strains grew with some alkenoic monoterpenes structurally related to p-cymene, e.g., α-terpinene. In addition, the isolates utilized p-isopropylbenzoate, and mono- and dicarboxylic aliphatic acids. Determination of the degradation balance of p-cymene and growth with acetate and nitrate indicated the capacity for complete oxidation of organic substrates under anoxic
conditions. Adaptation studies with cells of strain pCyN1 suggest the existence of at least two enzyme systems for anaerobic
alkylbenzene utilization, one metabolizing p-cymene and p-ethyltoluene, and the other metabolizing toluene. Excretion of p-isopropylbenzoate during growth on p-cymene indicated that the methyl group is the site of initial enzymatic attack. Although both strains were facultatively
aerobic, as revealed by growth on acetate under air, growth on p-cymene under oxic conditions was observed only with strain pCyN1. Strains pCyN1 and pCyN2 are closely related to members
of the Azoarcus-Thauera cluster within the β-subclass of the Proteobacteria, as revealed by 16S rRNA gene sequence analysis. This cluster encompasses
several described denitrifiers that oxidize toluene and other alkylbenzenes.
Received: 15 July 1998 / Revision received: 29 July 1999 / Accepted: 2 August 1999 相似文献
13.
Fernández MJ Adrio JL Piret JM Wolfe S Ro S Demain AL 《Applied microbiology and biotechnology》1999,52(4):484-488
Growth of Streptomyces clavuligerus NP1 in the presence of methanol or ethanol resulted in a marked increase in production of cephalosporin(s) from penicillin
G by resting cells. The mycelium produced in alcohol-supplemented medium was fragmented and dispersed as compared with growth
in control medium. HPLC analysis showed that at least two products were present in the biotransformation supernatant fluid
after 1 h incubation. One of them has been identified as deacetoxycephalosporin G (DAOG).
Received: 9 December 1998 / Received revision: 29 March 1999 / Accepted: 16 April 1999 相似文献
14.
Babu KR Swaminathan S Marten S Khanna N Rinas U 《Applied microbiology and biotechnology》2000,53(6):655-660
Escherichia coli TG1 transformed with a temperature-regulated interferon-α expression vector was grown to high cell density in defined medium
containing glucose as the sole carbon and energy source, utilizing a simple fed-batch process. Feeding was carried out to
achieve an exponential increase in biomass at growth rates which minimized acetate production. Thermal induction of such high
cell density cultures resulted in the production of ∼4 g interferon-α/l culture broth. Interferon-α was produced exclusively
in the form of insoluble inclusion bodies and was solubilized under denaturing conditions, refolded in the presence of arginine
and purified to near homogeneity, utilizing single-step ion-exchange chromatography on Q-Sepharose. The yield of purified
interferon-α was ∼300 mg/l with respect to the original high cell density culture broth (overall yield of ∼7.5% active interferon-α).
The purified recombinant interferon-α was found by different criteria to be predominantly monomeric and possessed a specific
bioactivity of ∼2.5 × 108 IU/mg based on viral cytopathic assay.
Received: 8 October 1999 / Received revision: 8 December 1999 / Accepted: 12 December 1999 相似文献
15.
Two Saccharomyces cerevisiae strains with different degrees of ethanol tolerance adapted differently to produced ethanol. Adaptation in the less ethanol-tolerant
strain was high and resulted in a reduced formation of ethanol-induced respiratory deficient mutants and an increased ergosterol
content of the cells. Adaptation in the more ethanol-tolerant strain was less pronounced. Journal of Industrial Microbiology & Biotechnology (2000) 24, 75–78.
Received 22 June 1999/ Accepted in revised form 06 October 1999 相似文献
16.
Extremophiles as a source of novel enzymes for industrial application 总被引:33,自引:0,他引:33
F. Niehaus C. Bertoldo M. Kähler G. Antranikian 《Applied microbiology and biotechnology》1999,51(6):711-729
Extremophilic microorganisms are adapted to survive in ecological niches such as at high temperatures, extremes of pH, high
salt concentrations and high pressure. These microorganisms produce unique biocatalysts that function under extreme conditions
comparable to those prevailing in various industrial processes. Some of the enzymes from extremophiles have already been purified
and their genes successfully cloned in mesophilic hosts. In this review we will briefly discuss the biotechnological significance
of extreme thermophilic (optimal growth 70–80 °C) and hyperthermophilic (optimal growth 85–100 °C) archaea and bacteria. In
particular, we will focus on selected extracellular-polymer-degrading enzymes, such as amylases, pullulanases, cyclodextrin
glycosyltransferases, cellulases, xylanases, chitinases, proteinases and other enzymes such as esterases, glucose isomerases,
alcohol dehydrogenases and DNA-modifying enzymes with potential use in food, chemical and pharmaceutical industries and in
environmental biotechnology.
Received: 14 August 1998 / Received revision: 17 February 1999 / Accepted: 19 February 1999 相似文献
17.
The review is focused on several aspects of butyric acid production: butyric acid-producing bacterial strains, the characteristics
of the genus Clostridium (the bacterium most used for butyrate production), and alternative methods of obtaining butyric acid by alcohol biotransformation.
Further, the main metabolic pathways of butyrate production, and possibilities for their control are outlined. Batch, fed-batch
or continuous fermentation combined with cell recycle or immobilization are applicable for anaerobic fermentations using Clostridium as the production strain. The best process comprises a combination of high cell concentration and slowly growing biomass,
in addition to high production selectivity and low inhibitory effects of the end-product. Inhibitory effects may be avoided
by on-line removal of the end-product. Extraction alone or extraction combined with simultaneous stripping of the organic
phase (liquid membrane) into the second aqueous phase (pertraction) seem to be the most suitable methods for on-line butyrate
removal. The biocompatibility and the distribution coefficient of the organic phase under fermentation conditions should be
considered before designing a fermentation apparatus. Journal of Industrial Microbiology & Biotechnology (2000) 24, 153–160.
Received 12 August 1999/ Accepted in revised form 03 December 1999 相似文献
18.
J. Ogawa A. Ryono S. -X. Xie R. M. Vohra R. Indrati H. Miyakawa T. Ueno Y. Ikenaka H. Nanba S. Takahashi S. Shimizu 《Applied microbiology and biotechnology》1999,52(6):797-801
N-Carbamoyl-d-α-amino acid amidohydrolase (d-carbamoylase) was found to distinguish stereochemistry not only at the α-carbon but also at the β-carbon of N-carbamoyl-d-α-amino acids. The enzyme selectively acted on one of the four stereoisomers of N-carbamoyl-α,β-diastereomeric amino acids. This simultaneous recognition of two chiral centers by d-carbamoylase was useful for the fine stereoselective synthesis of α,β-diastereomeric amino acids such as threonine, isoleucine,
3,4-methylenedioxyphenylserine and β-methylphenylalanine. The stereoselectivity for the β-carbon was influenced by the pH
of the reaction mixture and by the bulk of the substituent at the β-carbon.
Received: 18 June 1999 / Received revision: 30 July 1999 / Accepted: 6 August 1999 相似文献
19.
Acetobacter aceti have been grown on ethanol under inhibitory conditions created by high concentrations of phenol. A defined medium with no
vitamin or amino acid supplements has been used such that ethanol was the sole carbon substrate. The culture temperature was
maintained at 30 °C while the pH was manually controlled to fall within the range 4.5–6.0 during ethanol consumption. Growth
on ethanol at a few thousand milligrams per litre (below the known inhibitory level) resulted in a maximum specific growth
rate of 0.16 h−1 with a 95% yield of acetic acid, followed immediately by acetic acid consumption at a growth rate of 0.037 h−1. Phenol was found to inhibit growth by decreasing both the specific growth rate and the biomass yield during ethanol consumption.
On the other hand, the yield of acetic acid during ethanol consumption and the yield of biomass during acetic acid consumption
remained constant, independent of phenol inhibition. A model is presented and is shown to represent the phenol-inhibited growth
behaviour of A. aceti during both ethanol and acetic acid consumption.
Received: 6 November 1998 / Received revision: 8 February 1999 / Accepted: 12 February 1999 相似文献
20.
Puig-Grajales L Tan NG van der Zee F Razo-Flores E Field JA 《Applied microbiology and biotechnology》2000,54(5):692-697
Alkylphenols and fuel oxygenates are important environmental pollutants produced by the petrochemical industry. A batch biodegradability
test was conducted with selected ortho-substituted alkylphenols (2-cresol, 2,6-dimethylphenol and 2-ethylphenol), fuel oxygenates (methyl tert-butyl ether, ethyl tert-butyl ether and tert-amylmethyl ether) and tert-butyl alcohol (TBA) as model compounds. The ortho-substituted alkylphenols were not biodegraded after 100 days of incubation under methanogenic, sulfate-, or nitrate-reducing
conditions. However, biodegradation of 2-cresol and 2-ethylphenol (150 mg l−1) was observed in the presence of Mn (IV) as electron acceptor. The biodegradation of these two compounds took place in less
than 15 days and more than 90% removal was observed for both compounds. Mineralization was indicated since no UV-absorbing
metabolites accumulated after 23 days of incubation. These alkylphenols were also slowly chemically oxidized by Mn (IV). No
biodegradation of fuel oxygenates or TBA (1 g l−1) was observed after 80 or more days of incubation under methanogenic, Fe (III)-, or Mn (IV)-reducing conditions, suggesting
that these compounds are recalcitrant under anaerobic conditions. The fuel oxygenates caused no toxicity towards acetoclastic
methanogens activity in anaerobic granular sludge.
Received: 8 February 2000 / Received revision: 15 May 2000 / Accepted: 19 May 2000 相似文献