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1.
Alberto Domínguez Jose Gómez Miriam Lorenzo Ángeles Sanromán 《World journal of microbiology & biotechnology》2007,23(3):367-373
In the present paper the effect of adding veratryl alcohol and copper sulphate on laccase activity production by Trametes versicolor immobilized into alginate beads has been investigated. Employing copper sulphate as laccase inducer or supplementing the
culture medium with veratryl alcohol, led to maximum values of laccase activity. However, the highest laccase activity (around
4,000 U l−1) was obtained in cultures simultaneously supplemented with copper sulphate (3 mM) and veratryl alcohol (20 mM). These values
implied a considerable enhancement in relation to␣control cultures without any inducer (around 200 U l−1).
The production of laccase by immobilized T. versicolor in a 2-l airlift bioreactor with the optimized inducer has been evaluated. Laccase activities around 1,500 U l−1 were attained. The bioreactor operated for 44 days without operational problems and the bioparticles (fungus grows in alginate
beads) maintained their shape throughout the fermentation. Moreover, the extracellular liquid obtained was studied in terms
of pH and temperature activity and stability. On the other hand, anthracene was added in two-repeated batches in order to
determine the efficiency of this process to degrade pollutants. Near complete degradation was reached in both batches. Moreover,
in vitro degradation of several polycyclic aromatic hydrocarbons by crude laccase was also performed. 相似文献
2.
Saparrat Mario Carlos Nazareno Martínez María Jesús Tournier Horacio Alfio Cabello Marta Noemí Arambarri Angélica Margarita 《World journal of microbiology & biotechnology》2000,16(8-9):799-803
A comparative study on the extracellular ligninolytic enzymatic activity of five strains of Fusarium solani in a carbon-limited medium under shaking, revealed a differential production of these enzymes. Aryl alcohol oxidase (AAO)
activity was observed only in the supernatant of strain CLPS no. 568 with levels higher than 57 mU ml−1. Free extracellular laccase activity was detected in strains CLPS nos. 493, 568 and 570, strain no. 568 being the one which
showed the highest activity (over 8.6 mU ml−1). Free extracellular lignin peroxidase (LiP) activity was not detected in any isolate tested, whereas low levels of manganese-dependent
peroxidase (MnP) and manganese-independent peroxidase (MIP) activities were detected in certain isolates used. The AAO activity
of F. solani on primary α-alcohols such as veratryl alcohol, is reported for the first time; this enzyme activity is hydrogen-peroxide
independent. This is also the first report for extracellular MnP and MIP activities of F. solani.
This revised version was published online in November 2006 with corrections to the Cover Date. 相似文献
3.
Optimization of culture medium for the continuous cultivation of the microalga Haematococcus pluvialis 总被引:4,自引:0,他引:4
Fábregas J Domínguez A Regueiro M Maseda A Otero A 《Applied microbiology and biotechnology》2000,53(5):530-535
The freshwater microalga Haematococcus pluvialis is one of the best microbial sources of the carotenoid astaxanthin, but this microalga shows low growth rates and low final
cell densities when cultured with traditional media. A single-variable optimization strategy was applied to 18 components
of the culture media in order to maximize the productivity of vegetative cells of H. pluvialis in semicontinuous culture. The steady-state cell density obtained with the optimized culture medium at a daily volume exchange
of 20% was 3.77 · 105 cells ml−1, three times higher than the cell density obtained with Bold basal medium and with the initial formulation. The formulation
of the optimal Haematococcus medium (OHM) is (in g l−1) KNO3 0.41, Na2HPO4 0.03, MgSO4 · 7H2O 0.246, CaCl2 · 2H2O 0.11, (in mg l−1) Fe(III)citrate · H2O 2.62, CoCl2 · 6H2O 0.011, CuSO4 · 5H2O 0.012, Cr2O3 0.075, MnCl2 · 4H2O 0.98, Na2MoO4 · 2H2O 0.12, SeO2 0.005 and (in μg l−1]) biotin 25, thiamine 17.5 and B12 15. Vanadium, iodine, boron and zinc were demonstrated to be non-essential for the growth of H. pluvialis. Higher steady-state cell densities were obtained by a three-fold increase of all nutrient concentrations but a high nitrate
concentration remained in the culture medium under such conditions. The high cell productivities obtained with the new optimized
medium can serve as a basis for the development of a two-stage technology for the production of astaxanthin from H. pluvialis.
Received: 10 September 1999 / Received revision: 2 December 1999 / Accepted: 3 December 1999 相似文献
4.
Supplementation with CaCl2·2H2O (50 mg l−1) or CuSO4·5H2O (10 mg l−1) improved mannitol production by Candida magnoliae by 14.5 and 18.6% (25 and 32 g/L), respectively. When used in combination, they acted synergistically: Ca2+ decreased the intracellular concentration of mannitol 30%, whereas Cu2+ increased the intracellular activity of mannitol dehydrogenase 1.6-times more than control. Ca2+ probably works by altering the permeability of cells to mannitol, whereas, Cu2+ increases the activity of an enzyme responsible for mannitol biosynthesis. 相似文献
5.
Wei Tang Zhongchen Guo Fan Ouyang 《In vitro cellular & developmental biology. Plant》2001,37(5):558-563
Summary Mature zygotic embryos of eight (open-pollinated) families of loblolly pine (Pinus taeda L.) were cultured on eight different basal salt formulations, each supplemented with 36.2 μM 2,4-dichlorophenoxyacetic acid, 17.8 μM 6-benzyladenine, 18.6 μM kinetin, 500 mg l−1 casein hydrolysate, and 500 mg l−1
l-glutamine for 9 wk; embryogenic tissue was formed on cotyledons, hypocotyls, and radieles of mature zygotic embryos. Callus
was subcultured on the callus proliferation medium, the same as the induction medium but with one-fifth concentration of auxin
and cytokinin for 9 wk. On this medium a white to translucent, glossy, mucilaginous embryogenic callus containing embryogenic
suspensor masses (ESMs) was obtained. The highest frequency of explants forming embryogenic tissue, 17%, occurred on a modified
Murashige and Skoog salts basal medium containing the concentration of KNO3, Ca(NO3)2·4H2O, NH4NO3, KCl, ZnSO4·7H2O, and MnSO4·H2O, 720, 1900, 400, 250, 25.8, and 25.35 mg l−1, respectively. Embryogenic suspension cultures were established by culturing embryogenic callus in liquid callus proliferation
medium. Liquid cultures containing ESMs were transferred to medium containing abscisic acid, polyethylene glycols, and activated
charcoal for stimulating the production of cotyledonary somatic embryos. Mature somatic embryos germinated for 4–12 wk on
medium containing indole-butyric acid, gibberellic acid, 6-benzyladenine, activated charcoal, and reduced sucrose concentration
(15 g l−1). Two hundred and ninety-one regenerated plantlets were transferred to a perlite:peatmoss:vermiculite (1∶1∶1) mixture, then
the plants were transplanted to soil in the earth, and 73 plantlets survived in the field. 相似文献
6.
Bettin F Montanari Q Calloni R Gaio TA Silveira MM Dillon AJ 《Journal of industrial microbiology & biotechnology》2009,36(1):1-9
Some conditions in media composition for laccases production, such as different sources of carbon and organic nitrogen, antifoams
and a surfactant, were studied in liquid cultures of Pleurotus sajor-caju strain PS-2001. Cultivation with fructose or glucose as carbon sources produced maximum enzyme activities of 37 and 36 U mL−1, respectively. When sucrose was present in the medium, the best results were obtained using 5 g L−1 of this carbohydrate, on the 11th day of the process, attaining laccase titres of 13 U mL−1. In a medium without casein, practically no enzyme was produced during the experiments; among the sources of nitrogen studied,
pure casein led to the highest titres of laccase activity. Different concentrations of pure casein and sucrose were also tested.
As to the different concentrations of casein, the addition of 1.5 g L−1 resulted in the highest titres of laccase activity. Negligible levels of manganese peroxidase activity were also detected
in the culture medium. In low concentrations, polypropylene glycol or silicon-based antifoams and the surfactant Tween 80
have no significant influence on the formation of laccases by P. sajor-caju. However, enhanced concentration of polypropylene glycol negatively affected the production of laccases but favored the titres
in total peroxidases, lignin peroxidase and veratryl alcohol oxidase. 相似文献
7.
Chu WH 《Journal of industrial microbiology & biotechnology》2007,34(3):241-245
Thirty-five strains capable of secreting extracellular alkaline proteases were isolated from the soil and waste water near
the milk processing plant, slaughterhouse. Strain APP1 with the highest-yield alkaline proteases was identified as Bacillus sp. The cultural conditions were optimized for maximum enzyme production. When the initial pH of the medium was 9.0, the
culture maintained maximum proteolytic activity for 2,560 U ml−1 at 50°C for 48 h under the optimized conditions containing (g−1): soyabean meal, 15; wheat flour, 30; K2HPO4, 4; Na2HPO4, 1; MgSO4·7H2O, 0.1; Na2CO3, 6. The alkaline protease showed extreme stability toward SDS and oxidizing agents, which retained its activity above 73
and 110% on treatment for 72 h with 5% SDS and 5% H2O2, respectively. 相似文献
8.
Churapa Teerapatsakul Roberto Parra Christopher Bucke Lerluck Chitradon 《World journal of microbiology & biotechnology》2007,23(11):1519-1527
To engineer the production of laccase by Ganoderma sp. KU-Alk4, a newly isolated white-rot fungus, a seven-level Box−Behnken factorial design was employed to optimize the culture
medium composition. A mathematical model was developed to show the effect of each medium component and their interactions
on the production of laccase activity in submerged fermentation. The model estimated the optimal concentrations of glycerol,
yeast extract and veratryl alcohol as 40, 0.22 g/l and 0.85 mM, respectively, with the medium pH of 6.0. These predicted conditions
were verified by validation experiments. The optimized medium gave laccase activity of 240 U/ml, which is 12 times higher
than that produced in non-optimized medium. Thus, this statistical approach enabled rapid identification and integration of
key medium parameters for Ganoderma sp. KU-Alk4, resulted the high laccase production. 相似文献
9.
Fomes sclerodermeus produces manganese peroxidase (MnP) and laccase as part of its ligninolytic system. A Doehlert experimental design was applied in order to find the optimum conditions for MnP and laccase production. The factors studied were Cu2+, Mn2+ and asparagine. The present model and data analysis allowed us not only to define optimal media for production of both laccase and MnP, but also to show the combined effects between the factors. MnP was strongly influenced by Mn2+, which acts as an inducer. Under these conditions Cu2+ negatively affected MnP activity. At 13 days of growth 0.75 U ml–1 were produced in the optimized culture medium supplemented with 1 mM MnSO4 and 4 g l–1 asparagine. The laccase titer under optimized conditions reached maximum values at 16 days of growth: 13.5 U ml–1 in the presence of 0.2 mM CuSO4, 0.4 mM MnSO4 and 6 g l–1 asparagine. Mn2+ promoted production of both enzymes. There were important interactions among the nutrients evaluated, the most significant being those between Cu2+ and asparagine. 相似文献
10.
Teresa Alcántara Jose Gómez Marta Pazos M. Ángeles Sanromán 《World journal of microbiology & biotechnology》2007,23(8):1189-1194
In this work, the effect on laccase activity of adding xylidine, veratryl alcohol and copper sulphate to cultures of Coriolopsis rigida under submerged cultivation conditions have been investigated. The highest activities (approximately 6 × 105 nkat/l) were obtained when the inducers copper sulphate (2 mM) and xylidine (10 mM) were added simultaneously. In addition,
operating in the optimal conditions, it was possible to maintain the sustained production of laccase (around 3 × 105 nkat/l) for successive repeated batch cultures in an expanded-bed laboratory scale bioreactor. On the other hand, in vitro
phenol degradation by laccase obtained in the bioreactor was studied with/without an effective mediator 1-hydroxybenzotriazol
(HBT). The presence of a radical mediator plays an important role inducing the degradation of phenol, and without mediator
the polymerization of phenol was detected. 相似文献
11.
Guo Li-Qiong Lin Shuo-Xin Zheng Xiao-Bing Huang Zi-Rou Lin Jun-Fang 《World journal of microbiology & biotechnology》2011,27(3):731-735
A thermostable laccase was isolated from a tropical white-rot fungus Polyporus sp. which produced as high as 69,738 units of laccase l−1 in an optimized medium containing 20 g of malt extract l−1, 2 g of yeast extract l−1, 1.5 mM CuSO4. The laccase was purified to electrophoretic purity with a final purification of 44.70-fold and a recovery yield of 21.04%.
The purified laccase was shown to be a monomeric enzyme with a molecular mass of 60 kDa. The optimum temperature and pH value
of the laccase were 75°C and pH 4.0, respectively, for 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonate) (ABTS). The Michaelis–Menten
constant (K
m
) of the laccase was 18 μM for ABTS substrate. The laccase was stable at pH values between 5.5 and 7.5. About 80% of the initial
enzyme activity was retained after incubation of the laccase at 70°C for 2 h, indicating that the laccase was intrinsically
highly thermostable and with valuable potential applications. The laccase activity was promoted by 4.0 mM of Mg2+, Mn2+, Zn2+ and Ca2+, while inhibited by 4.0 mM of Co2+, Al3+, Cu2+, and Fe2+, showing different profiles of metal ion effects. 相似文献
12.
Hwang HS Lee SH Baek YM Kim SW Jeong YK Yun JW 《Applied microbiology and biotechnology》2008,78(3):419-429
In the present study, optimum culture conditions for the production of extracellular polysaccharides (EPS) in submerged culture
of an edible mushroom, Laetiporus sulphureus var. miniatus and their stimulatory effects on insulinoma cell (RINm5F) proliferation and insulin secretion were investigated. The maximum
mycelial growth (4.1 g l−1) and EPS production (0.6 g l−1) in submerged flask culture were achieved in a medium containing 30 g l−1 maltose, 2 g l−1 soy peptone, and 2 mM MnSO4·5H2O at an initial pH 2.0 and temperature 25°C. In the stirred-tank fermenter under optimized medium, the concentrations of mycelial
biomass and EPS reached a maximum level of 8.1 and 3.9 g l−1, respectively. Interestingly, supplementation of deep sea water (DSW) into the culture medium significantly increased both
mycelial biomass and EPS production by 4- and 6.7-fold at 70% (v/v) DSW medium, respectively. The EPS were proved to be glucose-rich polysaccharides and were able to increase proliferation
and insulin secretary function of rat insulinoma RINm5F cells, in a dose-dependent manner. In addition, EPS also strikingly
reduced the streptozotocin-induced apoptosis in RINm5F cells indicating the mode of the cytoprotective role of EPS on RINm5F
cells. 相似文献
13.
High production of laccase by a new basidiomycete, <Emphasis Type="Italic">Trametes</Emphasis> sp 总被引:1,自引:0,他引:1
A new basidiomycete, Trametes sp. 420, produced laccase at 6,810 U l−1 (268 mg, 25.4 U mg−1 protein for guaiacol) in glucose medium and 7,870 U l−1 (310 mg) in cellobiose medium with induction by 0.5 mM Cu2+ and 6 mM o-toluidine. Laccase isozyme E (LacE) was the sole laccase in the fermentation products. It was stable at pH 5–9 and below
70°C over 30 min. The K
m values of LacE for four substrates (guaiacol ABTS, 2,6-dimethoxyphenol and syringaldazine) varied from 5 to 245 μM. The activity
of LacE was strongly inhibited by NaN3 but not by EDTA or dimethylsulfoxide. LacE at 0.5 U l−1 could decolorize industrial dyes. The open reading frame of the lacE gene was 2,130 bp and was interrupted by 10 introns. It displayed a high homology to laccases from other fungi.
Pingui Tong and Yuzhi Hong contributed equally to the study 相似文献
14.
Z.T. Xing J.H. Cheng Q. Tan Y.J. Pan 《World journal of microbiology & biotechnology》2006,22(8):799-806
Summary Extracellular laccase in cultures of Grifola frondosa grown in liquid culture on a defined medium was first detectable in the early/middle stages of primary growth, and enzyme activity continued to increase even after fungal biomass production had peaked. Laccase production was significantly increased by supplementing cultures with 100–500 (M Cu over the basal level (1.6 mM Cu) and peak levels observed at 300 mM Cu were ∼
∼7-fold higher than in unsupplemented controls. Decreased laccase activity similar to levels detected in unsupplemented controls, as well as an adverse effect on fungal growth, occurred with further supplementation up to and including 0.9 mM Cu, but higher enzyme titres (2- to 16-fold compared with controls) were induced in cultures supplemented with 1–2 mM Cu2+. SDS-PAGE combined with activity staining revealed the presence of a single protein band (M
r ∼
∼70 kDa) exhibiting laccase activity in control culture fluids, whereas an additional distinct second laccase protein band (M
r␣∼
∼45 kDa) was observed in cultures supplemented with 1–2 mM Cu. Increased levels of extracellular laccase activity, and both laccase isozymes, were also detected in cultures of G. frondosa supplemented with ferulic, vanillic, veratric and 4-hydroxybenzoic acids, and 4-hydroxybenzaldehyde. The optimal temperature and pH values for laccase activity were 65 °C and pH 2.2 (using 2,2′-azinobis(3-ethylbenzthiazoline-6-sulfonate) {ABTS} as substrate), respectively, and the enzyme was relatively heat stable. In solid-state cultures of G. frondosa grown under conditions adopted for industrial-scale mushroom production, extracellular laccase levels increased during the substrate colonization phase, peaked when the substrate was fully colonized, and then decreased sharply during fruit body development. 相似文献
15.
Purification of recombinant laccase from Trametes versicolor in Pichia methanolica and its use for the decolorization of anthraquinone dye 总被引:1,自引:0,他引:1
A recombinant laccase from Trametes versicolor in Pichia methanolica was produced constitutively in a defined medium. The recombinant laccase was purified using ultrafiltration, anion-exchange
chromatography, and gel filtration. The molecular weight of the purified laccase was estimated as 64 kDa by SDS-PAGE. The
purified recombinant laccase decolorized more than 90% of Remazol Brilliant Blue R (RBBR) initially at 80 mg l−1 after 16 h at 45°C and pH 5 when 25 U laccase ml−1 was used. The purified recombinant laccase could efficiently decolorize RBBR without additional redox mediators. 相似文献
16.
Liangzhi Li Pei Kang Xin Ju Jiajia Chen Huibin Zou Cuiying Hu 《Preparative biochemistry & biotechnology》2018,48(3):257-263
Erythritol, a well-known natural sweetener, is mainly produced by microbial fermentation. Various metal ions (Al3+, Cu2+, Mn2+, and Ni2+) were added to the culture medium of Trichosporonoides oedocephalis ATCC 16958 at 30?mg/L in shake flask cultures. Compared with controls, Cu2+ increased the erythritol content by 86% and decreased the glycerol by-product by 31%. After 48 hr of shake flask culture, sodium dodecyl sulfate polyacrylamide gel electrophoresis showed that expression levels of erythrose reductase (ER) in the presence of 30?mg/L CuSO4?·?5H2O were higher than those obtained after treatment with other examined metal ions. Furthermore, after 108 hr of batch culture in a 5-L bioreactor, supplementation with 30?mg/L of CuSO4?·?5H2O increased the specific erythritol content by 27%. Further studies demonstrated that ER activity under 30?mg/L CuSO4?·?5H2O supplementation in a fermentor was overtly increased compared with the control after 60 hr, while glycerol-3-phosphate dehydrogenase activity was clearly reduced in most of the fermentation process. Furthermore, the NADPH/NADP ratio was slightly lower in T. oedocephalis cells treated with Cu2+ compared with control cells. These results provide further insights into Cu2+ effects on erythritol biosynthesis in T. oedocephalis and should improve the industrial production of erythritol by biological processes. 相似文献
17.
Mario C.N. Saparrat Marta N. Cabello Angélica M. Arambarri 《Biotechnology letters》2002,24(16):1375-1377
Tetraploa aristata CLPS 419 produced maximum extracellular laccase activity at over 9 mU ml–1 in shaking cultures supplemented with glucose and 3.5 mU ml–1 in sucrose-grown ones. Laccase activity did not exceed 0.7 mU ml–1 in stationary cultures with glucose and was not detected in similar cultures with sucrose or in ones grown on lignin. 相似文献
18.
Martin C Pecyna M Kellner H Jehmlich N Junghanns C Benndorf D von Bergen M Schlosser D 《Applied microbiology and biotechnology》2007,77(3):613-624
Myrioconium sp. strain UHH 1-13-18-4 is an ascomycete anamorph isolated from the river Saale, Central Germany. An extracellular, monomeric,
and glycosylated laccase with a molecular mass of 72.7 kDa as determined by matrix-assisted laser desorption/ionization-time
of flight-mass spectrometry and an isoelectric point below 2.8 was purified from CuSO4 and vanillic acid amended liquid fungal cultures grown in malt extract medium. The catalytic efficiencies (k
cat/K
m) for the oxidation of syringaldazine, 2,6-dimethoxyphenol, and 2,2′-azino-bis(3-ethylbenzthiazoline-6-sulfonate) were 67.3,
46.9, and 28.2 s−1 mM−1, respectively, with K
m values of 4.2, 67.8, and 104.9 μM. After pre-incubation at different pH values and temperatures for 1 h, more than 80% of
the initial laccase activity was retained between pH 4 to 6 and 15°C. The laccase-encoding gene was identified and sequenced
at both the genomic and complementary DNA (cDNA) level, and corresponding structural characteristics and putative regulatory
elements of the promoter region are reported. The identification of two tryptic peptides of the purified enzyme by mass spectrometry
confirmed the identity of the functional laccase protein with the translated genomic sequence of the Myrioconium sp. laccase. Myrioconium sp. laccase shows the highest degree of identity with laccases from ascomycetes belonging to the family Sclerotiniaceae, order Helotiales. 相似文献
19.
Extracellular laccase in cultures of Grifola frondosa grown in liquid culture on a defined medium was first detectable in the early/middle stages of primary growth, and enzyme activity continued to increase even after fungal biomass production had peaked. Laccase production was significantly increased by supplementing cultures with 100–500 μM Cu over the basal level (1.6 μM Cu) and peak levels observed at 300 μM Cu were 7-fold higher than in unsupplemented controls. Decreased laccase activity similar to levels detected in unsupplemented controls, as well as an adverse effect on fungal growth, occurred with further supplementation up to and including 0.9 mM Cu, but higher enzyme titres (2- to 16-fold compared with controls) were induced in cultures supplemented with 1–2 mM Cu2+. SDS-PAGE combined with activity staining revealed the presence of a single protein band (M
r 70 kDa) exhibiting laccase activity in control culture fluids, whereas an additional distinct laccase protein band (M
r 45 kDa) was observed in cultures supplemented with 1–2 mM Cu. Increased levels of extracellular laccase activity, and both laccase isozymes, were also detected in cultures of G. frondosa supplemented with ferulic, vanillic, veratric and 4-hydroxybenzoic acids, and 4-hydroxybenzaldehyde. Using 2,2′-azino-bis(ethylbenzothiazoline-6-sulfonate) (ABTS) as substrate, the optimal temperature and pH values for laccase activity were 65°C and pH 2.2, respectively, and the enzyme was relatively heat stable. In solid-state cultures of G. frondosa grown under conditions adopted for industrial-scale mushroom production, extracellular laccase levels increased during the substrate colonization phase, peaked when the substrate was fully colonized, and then decreased sharply during fruit body development. 相似文献
20.
The white-rot basidomycete Lentinula edodes often produces the lignin-degrading enzymes manganese peroxidase (MnP; EC 1.11.1.13) and laccase (Lcc; EC 1.10.3.2) in sawdust-based
media. In the present study, MnP from L. edodes was induced under liquid culture supplemented with sawdust extracts of Castanopsis
cuspidata. Lcc activity was induced by the addition of 2 mM CuSO4·5H2O into the same media 7 days after initial inoculation. Phenoloxidase enzymes were distinguished by polyacrylamide gel electrophoresis
(native-PAGE), followed by sequential enzymatic staining with an improved staining solution. The isozyme bands detected under
MnP-induced conditions were identified as manganese peroxidase (lemnp2) and bands detected under Lcc-induced conditions were
identified as laccase (lcc1) by Q-TOF mass spectrometry. 相似文献