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1.
The autolysis of chlamydospore-like cells in Phanerochaete chrysosporium immobilized in polyurethane foam correlated with the production of manganese peroxidase (MnP). The maximum specific activity of MnP was 1055 U g dry mycelium–1 in the immobilized culture, compared with 260 U g dry mycelium–1 in the submerged culture. Scattered mycelial pellets were formed in the immobilized culture in which almost all of the chlamydospore-like cells were subject to autolysis. However, highly crowded pellets were formed in the free culture, in which only the chlamydospore-like cells in the exterior were subject to autolysis. We propose that the enhanced production of MnP in immobilized cultures of P. chrysosporium is due to increased autolysis of the chlamydospore-like cells. 相似文献
2.
The effect of manganese and selected synthetic dyes on the production of manganese-dependent peroxidase (MnP) by Irpex lacteus immobilized on polyurethane foam was studied. In the cultures grown in a medium containing 65 μM Mn (II), up to three various
isoenzymes of MnP were resolved by isolectrofocusing, with pI values within the range of 3.50–6.04. In the cultures grown
in a medium containing 2.9 mM Mn (II), two new MnP isoforms (pI 3.28, 3.75) were produced. The addition of structurally different
synthetic dyes, an azo dye Reactive Orange 16 (RO16), an anthraquinonic dye Remazol Brilliant Blue R (RBBR), and a triphenylmethane
dye Bromophenol Blue (BPB), to the fungal cultures grown in the presence of high manganese inhibited the production of low
pI MnP isoforms. However, in the presence of BPB a new MnP isoform with pI 5.67 was detected. BPB was found to induce MnP
isoforms which are more effective in RBBR decolorization in vitro than the low pI isoforms present in the control cultures. 相似文献
3.
Juan-Pedro Elissetche André Ferraz Juanita Freer Jaime Rodríguez 《World journal of microbiology & biotechnology》2007,23(3):429-434
Enzymes produced by Ganoderma australe in solid-state fermentation and submerged cultures were evaluated. Strain A464 produced laccase activity in liquid medium
and in solid-state cultures containing Drimys winteri or Eucalyptus globulus wood chips, while MnP and LiP activities were not detected. On the other hand, strain A272 cultured for 75 days on E. globulus presented MnP activity of 719 IU/kg of wood. The suitability of D. winteri wood as a substrate enabling MnP production was checked with a well-documented MnP-producing basidiomycete, Ceriporiopsis subvermispora, which produced MnP activity of 327 IU/kg of wood in 9-day-old cultures. Data from two different G. australe strains (A272 and A464) indicated that MnP secretion depended on strain origin as well as on culture conditions. 相似文献
4.
Summary The production of the ligninolytic enzymes by Phanerochaete chrysosporium immobilized on polyurethane foam cubes in air was investigated by adopting different sizes and amounts of the carriers, different medium C/N ratios and different glucose-feeding strategies. No lignin peroxidase (LiP) activity was observed under nitrogen limitation (C/N ratio, expressed as glucose/NH4+, 56/2.2 mM) with two sizes and three amounts of the carriers, while comparable levels of manganese peroxidase (MnP) activities were detected only in non-immersed cultures with two sizes of the carriers. A non-immersed state also stimulated LiP formation under carbon limitation (C/N ratio 28/44 mM). High peak activities of LiP, 197 and 164 U/l, were obtained in non-immersed cultures under carbon limitation at the C/N ratios of 28/44 and 56/44 mM, respectively, the occurrence of the activities coinciding with the complete consumption of glucose. A very low level of MnP was measured at the C/N ratio of 28/44 mM compared with the similar activities at 56/2.2 and 56/44 mM. An addition of 2 g glucose/l after its complete depletion improved both the production of LiP and MnP markedly in non-immersed culture at the initial C/N ratio of 28/44 mM, whereas a replenishment of 5 g/l, still enhancing the formation of MnP, inhibited the production of LiP first before the later reactivation. It is suggested that non-immersed liquid culture under carbon limitation reinforced by a suitable glucose feeding strategy is one potential way to realize high production of the ligninolytic enzymes by P. chrysosporium in air. 相似文献
5.
Production of manganese peroxidase by pellet culture of the lignin-degrading basidiomycete, Pleurotus ostreatus 总被引:3,自引:0,他引:3
Pleurotus ostreatus No. 42 produced the ligninolytic enzymes, manganese peroxidase (MnP) and laccase, in agitation culture in glucose/peptone/wheat-bran medium. Formation of mycelial pellets 1-2 mm in diameter was essential for the production of MnP; and the concentration of dissolved oxygen in the culture medium greatly influenced the production of MnP, a concentration over 5 ppm being necessary for MnP production. The maximal activity of MnP was obtained on days 7-9 of culture, after the consumption of nutrient glucose. Introduction of oxygen from the start of the cultivation caused large pellet formation, which resulted in a low MnP activity level. P. ostreatus No. 42 produced two MnP isozymes in agitation culture. The major isozyme, F-2, was 36.4 kDa and had a pI of 3.95. The MnP characteristics, Km values, dependence on Mn2+ and optimum pH showed the similarity between this isozyme and MnP 3, which was produced under different culture conditions. Analysis of the N-terminal amino acid sequence indicated the close similarity of F-2 to MnP 3. 相似文献
6.
A. Karimi F. Vahabzadeh B. Bonakdarpour 《World journal of microbiology & biotechnology》2006,22(12):1251-1257
The mineral Kissiris, which is formed from the thickened foam of volcanic lava, was tested to approximate its mineral composition using energy-dispersive X-ray (EDX) analysis. The solid mineral contains silicon dioxide at about 16 (w/w). The considerable surface roughness of Kissiris along with its extensive porosity made this natural solid cell support an attractive candidate for manganese peroxidase (MnP) production for synthetic dye decolourization, at low cost. The white rot fungus Phanerochaete chrysosporium immobilized on the mineral Kissiris was grown in both stationary and agitated cultures (rotary shaker, 100 rev/min) using either carbon- or nitrogen-limited growth medium to study the ability of the fungus to degrade the synthetic dye methylene blue (MB). The value of residual dye for MB used at 60 ppm was 6% within 8 days of the incubation of the nitrogen-limited culture under the shaken conditions. Production of (MnP) occurred simultaneously in nitrogen-limited culture medium with the added MnSO4 at 100 ppm. The MnP activity was at relatively high level (170 U/l). 相似文献
7.
A novel dye-decolourizing strain of the bacterium Serratia marcescens efficiently decolourized two chemically different dyes Ranocid Fast Blue (RFB) and Procion Brilliant Blue-H-GR (PBB-HGR) belonging respectively to the azo and anthraquinone groups. Extracellular laccase and manganese peroxidase (MnP) activity were detected during dye decolourization. The involvement of MnP activity was found in the decolourization of both dyes. More than 90% decolourization of PBB-HGR and RFB was obtained on days 8 and 5, respectively at 26 °C under static conditions at pH 7.0. MnP activity was increased by the addition of Mn2+ · At 50 M Mn2+, high MnP (55.3 U/ml) but low laccase activity (8.3 U/ml) was observed. Influence of oxalic acid on MnP activity was also observed. 相似文献
8.
Bermek Hakan Gülseren İbrahim Li Kaichang Jung Hyunchae Tamerler Candan 《World journal of microbiology & biotechnology》2004,20(4):345-349
The morphology and ligninolytic enzyme production of a recently isolated wood-degrading fungus Trichophyton rubrum LSK-27 was investigated. In submerged cultures, the organism appeared to be an efficient manganese peroxidase (MnP) producer.
When grown in baffled and unbaffled shake flasks with three different working volume/total volume ratios (WV/TV 10, 25 and
50%), the organism displayed notable morphological differences, with variations in pellet shape and size. Cultivation in baffled
flasks with 25% WV/TV resulted in higher MnP and also laccase production as well as an earlier appearance of these enzymes
in culture broth. However, oxygen limitation conditions inhibited MnP and laccase production and resulted in considerable
changes in the morphology of this fungus. 相似文献
9.
10.
A white rot fungus Phlebia tremellosa produced lignin degrading enzymes, which showed degrading activity against various recalcitrant compounds. However, manganese
peroxidase (MnP) activity, one of lignin degrading enzymes, was very low in this fungus under various culture conditions.
An expression vector that carried both the laccase and MnP genes was constructed using laccase genomic DNA of P. tremellosa and MnP cDNA from Polyporus brumalis. P. tremellosa was genetically transformed using the expression vector to obtain fungal transformants showing increased laccase and MnP
activity. Many transformants showed highly increased laccase and MnP activity at the same time in liquid medium, and three
of them were used to degrade endocrine disrupting chemicals. The transformant not only degraded bisphenol A and nonylphenol
more rapidly but also removed the estrogenic activities of the chemicals faster than the wild type strain. 相似文献
11.
Among carbon sources studied, cellobiose and mannitol provided the highest laccase (Lac) activity (648 and 742 U1-1, respectively) of Trametes versicolor 775 while glucose gave maximum manganese peroxidase (MnP) and peroxidase activities (44 and 114U1-1, respectively). Citrus fruit peel as growth substrate enhanced Lac activity 7-fold when compared to the medium with cellobiose, whereas grape vine sawdust increased MnP and peroxidase activity up to 148 and 677U1-1, respectively. 相似文献
12.
Estrella MJ Pieckenstain FL Marina M Díaz LE Ruiz OA 《Journal of industrial microbiology & biotechnology》2004,31(3):122-126
Cheese whey (CW)-based growth medium efficiently protects Rhizobium loti cells during freezing and desiccation and can maintain their growth in a manner similar to that of traditional mannitol-based medium (YEM). The cheese-whey-based medium (CW) improved viability when used to re-suspend cell pellets kept at –20 °C and –80 °C and resulted in the survival of over 90% of the cells. Moreover, bacterial pellets obtained from cells grown in CW withstand desiccation better than cells grown in YEM. Survival was over 60% after 30 days at 4 °C. No differences were observed in nodulation efficiency between YEM-grown and CW-grown cells. Fast protein liquid chromatography (FPLC) protocols are presented for total protein profile analyses of sweet and acid cheese whey.In memoriam of Sylvio Cortina Vicepresident of Fundación COREPRO 相似文献
13.
Ola M. Gomaa John E. Linz C. A. Reddy 《World journal of microbiology & biotechnology》2008,24(10):2349-2356
Synthetic textile dyes are among the most dangerous chemical pollutants released in industrial wastewater streams. Recognizing
the importance of reducing the environmental impact of these dyes, the ability of the white rot fungus Phanerochaete chrysosporium to decolorize various textile dyes was investigated. This fungus decolorized 6 of the 14 structurally diverse dyes with varying
efficiency (between 14% and 52%). There was no discernable pattern of decolorization even among dyes of the same chemical
class, suggesting that attack on the dyes is relatively non-specific. Among the three dyes which showed >40% decolorization,
Victoria Blue B (VB) was chosen for further analysis because the ability of the fungus to decolorize VB was nearly independent
over a relatively broad concentration range. Blocking lignin peroxidase (LiP) and manganese peroxidase (MnP) production by
the fungus did not substantially affect VB decolorization. Inhibition of laccase production by adding various inhibitors to
shaken cultures reduced VB decolorization significantly suggesting a role for laccase in VB decolorization. When sodium azide
and aminotriazole were used to inhibit endogenous catalase and cytochrome P-450 oxygenase activities, there was 100% and 70%
reduction in VB decolorization, respectively. Adding benzoate to trap hydrogen peroxide-derived hydroxyl radicals resulted
in 50% decolorization of VB. Boiling the extracellular fluid (ECF) for 30 min resulted in approximately 50% reduction in VB
decolorization. Collectively, these data suggest that laccase, and/or oxygenase/oxidase and a heat-stable non-enzymatic factor,
but not Lip and MnP, play a role in VB decolorization by P. chrysosporium. 相似文献
14.
The cellsof Rhodococcus rhodochrous M33, which produce a nitrile hydratase enzyme, were immobilized in acrylamide-based polymer gels. The optimum pH and temperature
for the activity of nitrile hydratase in both the free and immobilized cells were 7.4 and 45°C, respectively, yet the optinum
temperature for acrylamide production by the immobilized cells was 20°C. The nitrile hydratase of the immobilized cells was
more stable with acrylamide than that of the free cells. Under optimal conditions, the final acrylamide concentration reached
about 400 g/L with a conversion yield of almost 100% after 8 h of reaction when using 150 g/L of immobilized cells corresponding
to a 1.91 g-dry cell weight/L. The enzyme activity of the immobilized cells rapidly decreased with repeated use. However,
the quality of the acrylamide produced by the immobilized cells was much better than that produced by the free cells in terms
of color, salt content, turbidity, and foam formation. The quality of the aqueous acrylamide solution obtained was found to
be of commercial use without further purification. 相似文献
15.
F. Vahabzadeh M. Mehranian A.R. Saatari 《World journal of microbiology & biotechnology》2004,20(8):859-864
Decolorization of molasses wastewater (MWW) from an ethanolic fermentation plant by Phanerochaete chrysosporium was studied. By diluting MWW properly (10%v/v) and incubating it with an appropriate concentration of the spores (2.5 × 106/ml), extensive decolorization occurred (75%) on day 5 of the incubation. The colour removal ability was found to be correlated to the activity of ligninolytic enzyme system: lignin peroxidase (LiP) activity was 185 U/l while manganese peroxidase (MnP) activity equaled 25 U/l. Effects of some selected operating variables were studied: manganese(II), veratryl alcohol (VA), glucose as a carbon source and urea and ammonium nitrate, each as a source of nitrogen. Results showed that the colour reduction and LiP activity were highest (76% and 186 U/l, respectively) either when no Mn(II) was added or added at the lowest level tested (0.16 mg/l to provide 0.3 mg/l). Activity of MnP was highest (25 U/l) when Mn(II) added to the diluted MWW at the highest level (100 ppm) while activity of LiP was lowest (7.1 U/l) at this level of added Mn(II). The colour reduction in the presence of the added VA was shown to be little less than in its absence (70 vs. 75%). When urea as an organic source of nitrogen for the fungus, was added to the MWW, the decolorizing activity of P. chrysosporium decreased significantly (15 vs. 75%) and no activities were detected for LiP and MnP. Use of ammonium nitrate as an inorganic source of nitrogen did not show such a decelerating effects, although no improvements in the metabolic behavior of the fungus (i.e., LiP and MnP activities) deaccelerating was observed. Effects of addition of glucose was also discussed. 相似文献
16.
Shinichi Yoshida Saori Yonehara Shigemi Minami Hyo-cheol Ha Kenji Iwahara Takashi Watanabe Yoichi Honda Masaaki Kuwahara 《Mycoscience》1996,37(4):417-425
Manganese peroxidase (MnP) and lignin peroxidase (LiP) were produced by growing a white-rot fungusBjerkandera adusta statically, on a wood meal/wheat bran culture in flasks. MnP and LiP reached their maximum activity after 6 and 19 days of
inoculation, respectively. Both MnP and LiP are thought to be important enzymes in lignin biodegradation byB. adusta. Ion exchange chromatography showed thatB. adusta produced a single LiP and a single MnP enzyme in wood meal/wheat bran culture. These enzymes were separated and characterized.
The molecular weight of MnP was 46,500 with a pl of 3.9. The molecular weight of LiP was estimated to be 47,000 with a pl of 3.5. Spectral analysis demonstrated that both enzymes are heme proteins. Production of these enzymes was also achieved
using a rotarysolid culture fermenter. MnP, LiP and veratryl alcohol oxidase were produced byB. adusta in the fermenter. 相似文献
17.
Javor Kac Janja Plazar Ale Mlinari
Bojana
egura Tamara T. Lah Metka Filipi
《Phytomedicine》2008,15(3):216-220
Bioassay-directed fractionation with a Salmonella/microsomal assay against the food borne mutagen 2-amino-3-methylimidazo[4,5-f]quinoline (IQ) was used to identify antimutagenic components of hops. Hops pellets extracted with diethylether showed antimutagenic activity against mutations induced by IQ. Fractionation of the diethylether extract (DE) by column chromatography, followed by semi-preparative HPLC yielded two fractions (E4b and E4d) with strong antimutagenic activity against IQ induced mutations. Separation of fraction E4b resulted in inactive fractions, while fraction E4d has been identified to be xanthohumol. In mammalian test system with human hepatoma HepG2 cells fraction E4d at 10 μg/ml completely prevented formation of IQ induced DNA damage. These results indicate that xanthohumol is a very promising potential protective agent against genotoxicity of food borne carcinogens, which warrants further investigation. 相似文献
18.
Effects of a fungal endophyte, Fusarium mairei, on growth and paclitaxel formation of Taxus cuspidata cells were investigated by adding fungal endophyte culture supernatant (FECS) to suspension cultures of T. cuspidata cells. The main effective chemical responsible for paclitaxel formation in FECS was an exopolysaccharide (EPS) of molecular
weight ~2 kDa. FECS fractions except EPS stimulated growth of Taxus cells but had no effects on paclitaxel accumulation. Additionally, elicitation efficiency of FECS based on different culture
conditions was studied. EPS content in FECS was related to FECS culture conditions. FECS with long cultivation and high-aeration
cultivation contained higher EPS content and resulted in higher paclitaxel yield than that with short cultivation and low-aeration
cultivation. The maximum yield of paclitaxel from Taxus cultures, elicited by FECS with 9-day cultivation, was 4.7-fold that of the control cultures. 相似文献
19.
Benoît Van Aken Philippe Ledent Henry Naveau Spiros N. Agathos 《Biotechnology letters》2000,22(8):641-646
Manganese peroxidase (MnP) from Phlebia radiata and glucose oxidase from Aspergillus niger were co-immobilized on porous silica beads. Immobilization of both enzymes on the same carrier provided an integrated system in which H2O2 required by MnP was produced by glucose oxidase. The immobilization process resulted in a decrease of both enzymatic activities and substrate affinities. However, immobilization improved the stability of MnP against H2O2 or high pH, as well as the storage stability of this enzyme. 相似文献
20.
White-rot fungi are extensively used in various submerged biotechnology processes to produce ligninolytic enzymes. Transfer
of the process from the laboratory to the industrial level requires optimization of the cultivation conditions on the laboratory
scale. An interesting area of optimization is pellet growth since this morphological form solves problems such as the decreased
oxygen concentration, limited heat, and nutrient transport, which usually occur in dispersed mycelium cultures. Many submerged
fermentations with basidiomycetes in pellet form were done with Phanerochaete, Trametes, and Bjerkandera species, among others. In our study, another promising basidiomycete, D. squalens, was used for ligninolytic enzyme production. With the addition of wood particles (sawdust) as a natural inducer and optimization
of mixing and aeration conditions in laboratory stirred tank (STR) and bubble column (BCR) reactors on pellet growth and morphology,
the secretion of laccase and the manganese-dependent peroxidase into the medium was substantially enhanced. The maximum mean
pellet radius was achieved after 10 days in the BCR (5.1 mm) where pellets were fluffy and 5 days in the STR (3.5 mm) where
they were round and smooth. The maximum Lac activity (1,882 U l−1) was obtained after 12 days in the STR, while maximum MnP activity (449.8 U l−1) occurred after 18 days in the BCR. The pellet size and morphology depended on the agitation and aeration conditions and
consequently influenced a particular enzyme synthesis. The enzyme activities were high and comparable with the activities
found for other investigations in reactors with basidiomycetes in the form of pellets. 相似文献