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1.
A. Pijanowska E. Kaczorek Ł. Chrzanowski A. Olszanowski 《World journal of microbiology & biotechnology》2007,23(5):677-682
Biodegradation and hydrophobicity of Pseudomonas spp. and Bacillus spp. strains were tested at different concentrations of the biosurfactant Quillaya saponin. A model mixture of hydrocarbon
(dodecane and hexadecane) was used for estimating the influence of surfactants on biodegradation. The bacterial adhesion to
hydrocarbon method for determination of bacterial cell surface hydrophobicity was exploited. Among the tested bacterial strains
the higher hydrophobicity was noticed for Pseudomonas aeruginosa TK. The hydrophobicity of this strain was 84%. The highest hydrocarbon biodegradation was observed for P. aeruginosa TK (49%) and Bacillus subtilis (35%) strains after 7 days of experiments. Generally the addition of Quillaya saponin increased hydrocarbon biodegradation
remarkably. The optimal concentration proved to be 80 mg l−1. The degree of hydrocarbon biodegradation was 75% for P. aeruginosa TK after the addition of saponin. However the most significant increase in biodegradation after addition of Quillaya saponin
was in the case of P. aeruginosa 25 and Pseudomonas putida (the increase of biodegradation from 21 to 52% and from 31 to 66%, respectively). It is worth mentioning that decrease of
hydrophobicity is correlated with the best biodegradation by P. aeruginosa strain. For the remaining strains, no significant hydrophobicity changes in relation to the system without surfactant were
noticed. 相似文献
2.
Guoying Wang Jianping Wen Hongmei Li Chunsheng Qiu 《Journal of industrial microbiology & biotechnology》2009,36(6):809-814
Strain Candida albicans PDY-07 was used to study the anaerobic biodegradation of phenol and m-cresol as single and dual substrates in batch cultures. The strain had a higher potential to degrade phenol than m-cresol. The cell growth kinetics of batch cultures with various initial m-cresol concentrations was investigated, and the Haldane kinetic model adequately described the dynamic behavior of cell growth
on m-cresol. When cells grew on the mixture of phenol and m-cresol, substrate interactions were observed. Phenol inhibited the utilization of m-cresol; on the other hand, m-cresol also inhibited the degradation of phenol. However, the presence of low-concentration phenol enhanced m-cresol biodegradation; 100 mg/l m-cresol could be completely degraded within a shorter period of time than m-cresol alone in the presence of 150–300 mg/l phenol. The maximum m-cresol biodegradation rate was obtained at the existence of 200 mg/l phenol. Phenol was preferably utilized by the strain
as a carbon and energy source. In addition, a sum kinetics model was used to describe the cell growth behavior in binary mixture
of phenol and m-cresol, and the interaction parameters were determined. The model adequately predicted the growth kinetics and the interaction
between the substrates. 相似文献
3.
Ł. Chrzanowski E. Kaczorek A. Olszanowski 《World journal of microbiology & biotechnology》2005,21(6-7):1273-1277
Summary The growth of Candida maltosa on hydrocarbons (dodecane and hexadecane) was influenced by adding various natural and synthetic surfactants. Microbial adhesion
to the hydrocarbon was used to measure the surface cell hydrophobicity of the yeast, which in the presence of a synthetic
surfactant correlated with the degree of hydrocarbon biodegradation. Non-ionic surfactants caused the highest degree of hydrocarbon
biodegradation corresponding the lowest hydrophobicity. A different correlation was observed with natural surfactants, of
which saponin was the most effective for hydrocarbon biodegradation, though the concentration of this surfactant had no influence
on surface cell hydrophobicity. 相似文献
4.
Biodegradation of phenol and 4-chlorophenol by the yeast <Emphasis Type="Italic">Candida tropicalis</Emphasis> 总被引:2,自引:0,他引:2
Biodegradation of phenol and 4-chlorophenol (4-cp) using a pure culture of Candida tropicalis was studied. The results showed that C. tropicalis could degrade 2,000 mg l−1 phenol alone and 350 mg l−1 4-cp alone within 66 and 55 h, respectively. The capacity of the strain to degrade phenol was obviously higher than that
to degrade 4-cp. In the dual-substrate system, 4-cp intensely inhibited phenol biodegradation. Phenol beyond 800 mg l−1 could not be degraded in the presence of 350 mg l−1 4-cp. Comparatively, low-concentration phenol from 100 to 600 mg l−1 supplied a sole carbon and energy source for C. tropicalis in the initial phase of biodegradation and accelerated the assimilation of 4-cp, which resulted in the fact that 4-cp biodegradation
velocity was higher than that without phenol. And the capacity of C. tropicalis to degrade 4-cp was increased up to 420 mg l−1 with the presence of 100–160 mg l−1 phenol. In addition, the intrinsic kinetics of cell growth and substrate degradation were investigated with phenol and 4-cp
as single and mixed substrates in batch cultures. The results illustrated that the models proposed adequately described the
dynamic behaviors of biodegradation by C. tropicalis. 相似文献
5.
Anaerobic biodegradation of phenol by <Emphasis Type="Italic">Candida albicans</Emphasis> PDY-07 in the presence of 4-chlorophenol 总被引:1,自引:0,他引:1
Guoying Wang Jianping Wen Guanghai Yu Hongmei Li 《World journal of microbiology & biotechnology》2008,24(11):2685-2691
Biodegradation of phenol and 4-chlorophenol (4-cp) using pure culture of Candida albicans PDY-07 under anaerobic condition was studied. The results showed that the strain could completely degrade up to 1,800 mg/l
phenol within 68 h. The capacity of the strain to degrade phenol was higher than that to degrade 4-cp. In the dual-substrate
system, 4-cp intensely inhibited phenol biodegradation. Comparatively, low-concentration phenol from 25 to 150 mg/l supplied
a carbon and energy source for Candida albicans PDY-07 in the early phase of biodegradation and accelerated the assimilation of 4-cp, which resulted in that 50 mg/l 4-cp
was degraded within less time than that without phenol. While the biodegradation of 50 mg/l 4-cp was inhibited in the presence
of 200 mg/l phenol. In addition, the intrinsic kinetics of cell growth and substrate degradation were investigated with phenol
and 4-cp as single and dual substrates in batch cultures. The results demonstrated that the models adequately described the
dynamic behaviors of biodegradation by Candida albicans PDY-07. 相似文献
6.
Basic Violet 3 (BV) belongs to the most important group of synthetic colorants and is used extensively in textile industries.
It is considered as xenobiotic compound which is recalcitrant to biodegradation. As Candida krusei could not use BV as sole carbon source, experiments were conducted to study the effect of cosubstrates on decolorization
of BV in semi synthetic medium using glucose, sucrose, lactose, maltose, yeast extract, peptone, urea and ammonium sulphate.
Maximum decolorization (74%) was observed in media supplemented with sucrose. Use of sugarcane bagasse extract as sole nutrient
source showed 100% decolorization of BV within 24 h under optimized condition. UV–visible, FTIR spectral analysis and HPLC
analysis confirmed the biodegradation of BV. Six degradation products were isolated and identified. We propose the biodegradation
pathway for BV which occurs via stepwise reduction and demethylation process to yield mono-, di-, tri-, tetra-, penta- and
hexa-demethylated BV species which was degraded completely. The study of the enzymes responsible for decolorization showed
the activities of lignin peroxidase, lacasse, tyrosinase, NADH-DCIP reductase, MG reductase and azoreductase in cells before
and after decolorization. A significant increase in activities of NADH-DCIP reductase and laccase was observed in the cells
after decolorization. The yeast C. krusei could show the ability to decolorize the textile dye BV using inexpensive source like sugarcane bagasse extract for decolorization. 相似文献
7.
Biodegradation of textile azo dye by <Emphasis Type="Italic">Shewanella decolorationis</Emphasis> S12 under microaerophilic conditions 总被引:3,自引:0,他引:3
The complete biodegradation of azo dye, Fast Acid Red GR, was observed under microaerophilic conditions by Shewanella decolorationis S12. Although the highest decolorizing rate was measured under anaerobic condition and the highest biomass was obtained under
aerobic condition, a further biodegradation of decolorizing products can only be achieved under microaerophilic conditions.
Under microaerophilic conditions, S. decolorationis S12 could use a range of carbon sources for azo dye decolorization, including lactate, formate, glucose and sucrose, with
lactate being the optimal carbon source. Sulfonated aromatic amines were not detected during the biotransformation of Fast
Acid Red GR, while H2S formed. The decolorizing products, aniline, 1,4-diaminobenzene and 1-amino-2-naphthol, were followed by complete biodegradation
through catechol and 4-aminobenzoic acid based on the analysis results of GC-MS and HPLC. 相似文献
8.
This study investigated the enhanced crude oil biodegradability of Pseudomonas aeruginosa ZJU, a strain isolated from the Shengli oil field (Shandong Province, China), after preservation in a crude oil-containing
medium. This strain previously could not emulsify crude oil during preservation, but after switching to a subculture in a
glycerol medium for passages, it expressed increased biodegradation of crude oil within the first six passages and this biodegradation
sharply decreased after the seventh passage. It is noticed that about 70% of crude oil was degraded by Pseudomonas aeruginosa ZJU in the third passage while this biodegradability was less than 19% in the seventh passage. Similar to the trend on biodegradation
of crude oil, rhamnolipid production increased during the first six passages and later sharply decreased. Thus, it seems that
biodegradability was proportionally related to the rhamnolipid productivity in each passage in glycerol medium. Interestingly,
both rhamnolipid production and crude oil biodegradation were maintained if this strain was continuously preserved in crude
oil and could be retrieved if this strain was then re-preserved in crude oil-containing medium for seven days after the significant
decline in these two characteristics previously observed in the seventh passage. 相似文献
9.
Eric E. Igbinigie Simon Aktins Yvonne van Breugel Susan van Dyke Michael T. Davies-Coleman Peter D. Rose Professor 《Biotechnology journal》2008,3(11):1407-1416
Cynodon dactylon (Bermuda grass) has been observed to grow sporadically on the surface of coal dumps in the Witbank coal mining area of South Africa. Root zone investigation indicated that a number of fungal species may be actively involved in the biodegradation of hard coal, thus enabling the survival of the plant, through mutualistic interaction, in this extreme environment. In an extensive screening program of over two thousand samples, the Deuteromycete, Neosartorya fischeri, was isolated and identified. The biodegradation of coal by N. fischeri was tested in flask studies and in a perfusion fixed-bed bioreactor used to simulate the coal dump environment. The performance of N. fischeri was compared to Phanaerochaete chrysosporium and Trametes (Polyporus) versicolor, previously described in coal biodegradation studies. Fourier transform infrared spectrometry and pyrolysis gas chromatography mass spectrometry of the biodegradation product indicated oxidation of the coal surface and nitration of the condensed aromatic structures of the coal macromolecule as possible reaction mechanisms in N. fischeri coal biodegradation. This is a first report of N. fischeri-mediated coal biodegradation and, in addition to possible applications in coal biotechnology, the findings may enable development of sustainable technologies in coal mine rehabilitation. 相似文献
10.
Zeng G Liu Z Zhong H Li J Yuan X Fu H Ding Y Wang J Zhou M 《Applied microbiology and biotechnology》2011,90(3):1155-1161
The effect of monorhamnolipid (monoRL) on the degradation of n-hexadecane by Candida tropicalis was investigated in this study. The concentration of hexadecane, cell growth, cell surface hydrophobicity (CSH), cell surface
zeta potential (CSZP), and FT-IR spectra of cellular envelope were tested to determine the mechanisms. MonoRL at the initial
concentrations of 11.4, 19, and 38 mg/l improved the degradation of hexadecane, and 19 mg/l was the best concentration. However,
114 mg/l monoRL suppressed the biodegradation probably because of the reduced bioavailability of hexadecane caused by the
micelles. The presence of monoRL changed the cell surface properties, which was demonstrated by the increased CSH, the increased
CSZP, and the changed FT-IR spectra of cellular envelope at 680 and 620 cm−1. The changes of cell surface properties may be a reason for the enhanced biodegradation of hexadecane by the yeast. The results
indicate the potential application of monoRL in the bioremediation of hydrocarbons. 相似文献
11.
OVAT (one variable at a time) approach was applied in this study to screen the most important physicochemical key determinants
involved in the process of sheep wool biodegradation. The process was directed by a keratinase-producing Bacillus subtilis DB 100 (p5.2) recombinant strain. Data indicate that, sheep wool could be degraded efficiently in cultures incubated at 30°C,
with initial pH of 7 with agitation at 150 rpm. Two times autoclaved alkali treated and undefatted chopped sheep wool is more
accessible to biodegradation. B. subtilis recombinant cells could utilize sheep wool as a sole source of carbon and nitrogen. Sheep wool-based modified basal medium
II, lacking NH4Cl and yeast extract, could greatly support the growth of these bacterial cells. Sheep wool biodegradation was conducted efficiently
in the absence of kanamycin consequently; high stability of the recombinant plasmid (p5.2) represents a great challenge upon
scaling up this process. Three key determinants (sheep wool concentration, incubation time and inoculum size) imposing considerable
constraints on the process are highlighted. Sheep wool-based tap water medium and sheep wool-based distilled water medium
were formulated in this study. High levels of released end products, produced from sheep wool biodegradation are achieved
upon using these two sheep wool-based water media. Data indicate that, sheep wool hydrolysate is rich in some amino acids,
such as tyrosine, phenylalanine, lysine, proline, isoleucine, leucine, valine, aspartic acid and glutamic acid. Moreover,
the resulting sheep wool hydrolysate contains soluble proteins of high and intermediate molecular weights. The present study
demonstrates a feasible, cheap, reproducible, efficient and rapid biotechnological approach towards utilization of raw sheep
wool waste through a recombinant bacterium. 相似文献
12.
Microbial adhesion is an important factor that can influence biodegradation of poorly water soluble hydrocarbons such as phenanthrene.
This study examined how adhesion to an oil–water interface, as mediated by 1-dodecanol, enhanced phenanthrene biodegradation
by Pseudomonas fluorescens LP6a. Phenanthrene was dissolved in heptamethylnonane and added to the aerobic aqueous growth medium to form a two phase
mixture. 1-Dodecanol was non-toxic and furthermore could be biodegraded slowly by this strain. The alcohol promoted adhesion
of the bacterial cells to the oil–water interface without significantly changing the interfacial or surface tension. Introducing
1-dodecanol at concentrations from 217 to 4,100 mg l−1 increased phenanthrene biodegradation by about 30% after 120 h incubation. After 100 h incubation, cultures initially containing
120 or 160 mg l−1 1-dodecanol had mineralized >10% of the phenanthrene whereas those incubated without 1-dodecanol had mineralized only 4.5%.
The production and accumulation of putative phenanthrene metabolites in the aqueous phase of cultures likewise increased in
response to the addition of 1-dodecanol. The results suggest that enhanced adhesion of bacterial cells to the oil–water interface
was the main factor responsible for enhanced biodegradation of phenanthrene to presumed polar metabolites and to CO2. 相似文献
13.
Ikegaya H Nakase T Iwata K Tsuchida H Sonobe S Shimmen T 《Journal of plant research》2012,125(3):457-464
We succeeded in inducing conjugation of Spirogyra
castanacea by incubating algal filaments on agar plate. Conjugation could be induced using clone culture. The scalariform conjugation
was generally observed, while lateral conjugation was rarely. When two filaments formed scalariform conjugation, all cells
of one filament behaved as male and those of other filament did as female. Very rarely, however, zygospores were formed in
both of pair filaments. The surface of conjugation tube was stained with fluorescently labeled-lectins, such as Bandeiraea (Griffonia) simplicifolia lectin (BSL-I) and jacalin. BSL-I strongly stained the conjugation tubes, while weakly did the cell surface of female gamete
first and then that of male gamete. Jacalin stained mainly the conjugation tubes. Addition of jacalin inhibited the formation
of papilla, suggesting some important role of jacalin-binding material at the initial step of formation of the conjugation
tubes. 相似文献
14.
R. Jayakumar V.V. Divya Rani K.T. Shalumon P.T. Sudheesh Kumar S.V. Nair T. Furuike H. Tamura 《International journal of biological macromolecules》2009,45(3):260-264
Chitin is a novel biopolymer and has excellent biological properties such as biodegradation in the human body and biocompatible, bioabsorable, antibacterial and wound healing activities. In this work, α- and β-chitin membranes were prepared using α- and β-chitin hydrogel. The bioactivity studies were carried out using these chitin membranes with the simulated body fluid solution (SBF) for 7, 14 and 21 days. After 7, 14 and 21 days the membranes were characterized using SEM, EDS and FT-IR. The SEM, EDS and FT-IR studies confirmed the formation of calcium phosphate layer on the surface of the both chitin membranes. These results indicate that the prepared chitin membranes were bioactive. Cell adhesion studies were also carried out using MG-63 osteoblast-like cells. The cells were adhered and spread over the membrane after 24 h of incubation. These results indicated that the chitin membranes could be used for tissue-engineering applications. 相似文献
15.
Grażyna A. Płaza Jacek Wypych Christopher Berry Robin L. Brigmon 《World journal of microbiology & biotechnology》2007,23(4):533-542
The fate of benzene, ethylbenzene, toluene, xylenes (BTEX) compounds through biodegradation was investigated using two different
bacteria, Ralstonia picketti (BP-20) and Alcaligenes piechaudii (CZOR L-1B). These bacteria were isolated from extremely polluted soils contaminated with petroleum hydrocarbons. PCR and
Fatty Acid Methyl Ester (FAME) were used to identify the isolates. In this study, BTEX biodegradation, applied as a mixture
or as individual compounds by the bacteria was evaluated. Both bacteria were shown to degrade each of the BTEX compounds individually
and in mixture. However, Alcaligenes piechaudii was a better degrader of BTEXs both in the mixture and individually. Differences between BTEX biodegradation in the mixture
and individually were observed, especially in the case of benzene. The degradation of all BTEXs in the mixture was lower than
the degradation of individual compounds for both bacteria tested. In the all experiments, toluene and m + p- xylenes were better removed than the other BTEXs. No intermediates of biodegradation were detected. Biosurfactant production
was observed by culture techniques. In addition, 3-hydroxy fatty acids, important in biosurfactant production, were observed
by FAME analysis. The test results indicate that the bacteria could contribute to bioremediation of aromatic hydrocarbon pollution. 相似文献
16.
Pseudomonas putida and Pseudomonas fluorescens present as a coculture were studied for their abilities to degrade benzene, toluene, ethylbenzene, and xylenes (collectively known as BTEX) under various growth conditions. The coculture effectively degraded various concentrations of BTEX as sole carbon sources. However, all BTEX compounds showed substrate inhibition to the bacteria, in terms of specific growth, degradation rate, and cell net yield. Cell growth was completely inhibited at 500mgl–1 of benzene, 600mgl–1 of o-xylene, and 1000mgl–1 of toluene. Without aeration, aerobic biodegradation of BTEX required additional oxygen provided as hydrogen peroxide in the medium. Under hypoxic conditions, however, nitrate could be used as an alternative electron acceptor for BTEX biodegradation when oxygen was limited and denitrification took place in the culture. The carbon mass balance study confirmed that benzene and toluene were completely mineralized to CO2 and H2O without producing any identifiable intermediate metabolites. 相似文献
17.
Sarfraz Hussain Muhammad Arshad Baby Shaharoona Muhammad Saleem Azeem Khalid 《World journal of microbiology & biotechnology》2009,25(5):853-858
The rates of biodegradation of endosulfan by P. aeruginosa were determined with different initial endosulfan concentrations (10, 50, 100, 150, 200 and 250 mg l−1) and different growth linked kinetic models were fitted at these concentrations. At 10 mg endosulfan l−1, Monod no growth model was well fitted. Monod with growth model described the biodegradation pattern at an initial concentration
of 50, 100 and 150 mg endosulfan l−1. Significant increases of P. aeruginosa MN2B14 density in broth culture during incubation further support this result. Conversely, zero order kinetic model was well
fitted into the biodegradation data if initial endosulfan concentration was ≥200 mg endosulfan l−1. The kinetics of endosulfan biodegradation by P. aeruginosa MN2B14 in liquid broth was highly dependent upon its initial concentration. The results of this study could be employed for
predicting the persistence of endosulfan in water environment containing P. aeruginosa as an endosulfan degrading bacterium. 相似文献
18.
D. A. Kadimaliev V. V. Revin N. A. Atykyan O. S. Nadezhina A. A. Parshin 《Applied Biochemistry and Microbiology》2011,47(1):66-71
The possibility of the usage of Lentinus tigrinus fungus strain VKM F-3616D for biodegradation of high (up to 5%) phenol concentrations in liquid medium and the involvement
of laccase and peroxidase in this process have been studied. L. tigrinus fungus was demonstrated to effectively degrade phenol with easy biomass deletion from the liquid. Decrease in phenol concentration
was accompanied by increased secretion level and laccase activity at the preliminary stages of biodegradation, while that
of peroxidase was at the latest stages of biodegradation. These enzyme secretions in distinct ratios and consequences are
necessary for effective phenol biodegradation. An effective approach for phenol concentration decrease in the waste water
of smoking shops in meat-processing factories using L. tigrinus fungus was described. 相似文献
19.
An alkane-biodegrading bacterium identified as Rhodococcus erythropolis (NTU-1 strain) was isolated from petroleum contaminated soil. The major purpose of the current research was to study the issues regarding biofloccules formation and cell surface hydrophobicity of NTU-1. When long-chain alkanes are supplied as the carbon source, NTU-1 tends to form biofloccules and remove significant amount of alkanes by biodegradation and physical trapping. Approximately, more than 95% of each alkane could be efficiently removed within 40–68 h. The bioremediation process was accompanied by formation of biofloccules with size ranging from 0.1 to 2 cm in diameter. The MATH test and the hydrophobic slide experiment suggested that NTU-1 might possess a hydrophobic cell surface which is one of the important factors in the formation of biofloccules. It provides the interaction of cells with hydrocarbon droplets effectively and further aggregate into larger clumps. Besides, when grown on n-hexadecane, experimental results revealed that there were at least 11 different growth-associated fatty acids produced, with carbon chain length ranging from 12 to 24, and cell surface hydrophobicity was enhanced via accumulation at the cell surface. 相似文献
20.
2-Mercaptobenzothiazolyl-(Z)-(2-aminothiazol-4-yl)-2-(tert-butoxycarbonyl) isopropoxyiminoacetate is used as supplementary additives in commercial-grade insecticides to compensate
for the time factor needed for the actual pesticide chemical to start its action. This investigation describes the biodegradation
of 2-mercaptobenzothiazolyl-(Z)-(2-aminothiazol-4-yl)-2-(tert-butoxycarbonyl) isopropoxyiminoacetate by Pseudomonas desmolyticum NCIM 2112. The biodegradation is influenced by other carbon and nitrogen sources and indicates that glucose and lactose are
effective at 0.5% concentration whereas NaNO3 and NaNO2 at 0.05%. The percent degradation of 2-mercaptobenzothiazolyl-(Z)-(2-aminothiazol-4-yl)-2-(tert-butoxycarbonyl) isopropoxyiminoacetate was found to be 40%.The pH and temperature optima were found to be 7.0°C and 30°C,
respectively. The effect on soil parameters was observed in treated soil and indicates remarkable decrease in soil fertility;
the phytotoxicity indicates retarded growth and germination inhibition of treated seeds of Sorghum bicolor and Triticum aestivum. In paddy field the inhibition of germination of Oryza sativa was observed. 相似文献