共查询到20条相似文献,搜索用时 31 毫秒
1.
Peng Wang Xiaoke Hu Sean Cook Maria Begonia Ken S. Lee Huey-Min Hwang 《World journal of microbiology & biotechnology》2008,24(10):2205-2212
The present work was carried out to determine the optimum culture conditions of Phanerochaete chrysosporium (ATCC 20696) for maximizing ligninolytic enzyme production. Additionally, separation of its lignin peroxidase was conducted.
After experiments, an optimized culture medium/condition was constructed (per liter of Kirk’s medium): dextrose 10 g, ammonium
tartrate 0.11 g, Tween-80 0.5 g, MnSO4 7 mg, and veratryl alcohol 0.3 g in 10 mM acetic acid buffer pH 4.5. Under the optimized experimental condition, both lignin
peroxidase (LiP) and manganese peroxidase (MnP) were detected and reach the highest yield at 30°C on the 8th day culture.
Salt precipitation methods was used in the extraction and purification processes. Results show that salt precipitation with
60% (NH4)2SO4 yielded the best result, especially toward LiP. Enzyme separation was conducted and two fractions with LiP activity. LiP1
and LiP2 were produced using three columns sequentially: desalting column, Q FF ion exchange column and Sepharyl S-300 HR
gel filtration. LiP1 and LiP2 had been purified by 9.6- and 7.6-fold with a yield of 22.9% and 18.6%, respectively. According
to the data of sodium dodecyl sulfate polyacrilamide gel electrophoresis (SDS-PAGE), the molecular weights of the enzymes
are 38 kDa and 40 kDa, respectively. 相似文献
2.
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
3.
Simultaneous isomerisation and fermentation (SIF) of xylose and simultaneous isomerisation and cofermentation (SICF) of glucose-xylose
mixture was carried out by the yeastSaccharomyces cerevisiae in the presence of a compatible xylose isomerase. The enzyme converted xylose to xylulose andS. cerevisiae fermented xylulose, along with glucose, to ethanol at pH 5.0 and 30°C. This compatible xylose isomerase fromCandida boidinii, having an optimum pH and temperature range of 4.5–5.0 and 30–50°C respectively, was partially purified and immobilized on
an inexpensive, inert and easily available support, hen egg shell. An immobilized xylose isomerase loading of 4.5 IU/(g initial
xylose) was optimum for SIF of xylose as well as SICF of glucose-xylose mixture to ethanol byS. cerevisiae. The SICF of 30 g/L glucose and 70 g xylose/L gave an ethanol concentration of 22.3 g/L with yield of 0.36 g/(g sugar consumed)
and xylose conversion efficiency of 42.8%. 相似文献
4.
Cultural conditions on mycelial growth and fruit-body formation ofMycena chlorophos were studied. The optimum temperature of the mycelial growth was 27°C and the optimum initial pH of medium was 4.0. Peptone
agar medium was suitable for the spawn culture. Compost medium containing rice bran at 10% (fw/fw) was appropriate for fruitbody
formation in the Petri dish. Light was essential for initiation of primordia, and low-temperature treatment induced fruit-body
formation effectively. The optimum conditions for fruit-body formation were found to be the cultivation at 27°C for 4 wk and
continued cultivation for 3 wk under illumination at an intensity above 0.2 lx and at 21°C after casing with moist compost
powder. In the fruit-bodies obtained, the maximum photosensitive wavelength of luminescence was 522 nm and the optimum temperature
for emission was 27°C. The luminescence of a fruit-body was observed for about 3 d consecutively at 21°C. 相似文献
5.
Moredo N. Lorenzo M. Domínguez A. Moldes D. Cameselle C. Sanroman A. 《World journal of microbiology & biotechnology》2003,19(7):665-669
Ligninolytic enzyme production by the white-rot fungi Phanerochaete chrysosporium and Trametes versicolor precultivated with different insoluble lignocellulosic materials (grape seeds, barley bran and wood shavings) was investigated. Cultures of Phanerochaete chrysosporium precultivated with grape seeds and barley bran showed maximum lignin peroxidase (LiP) and manganese-dependent peroxidase (MnP) activities (1000 and 1232 U/l, respectively). Trametes versicolor precultivated with the same lignocellulosic residues showed the maximum laccase activity (around 250 U/l). For both fungi, the ligninolytic activities were about two-fold higher than those attained in the control cultures. In vitro decolorization of the polymeric dye Poly R-478 by the extracellular liquid obtained in the above-mentioned cultures was monitored in order to determine the respective capabilities of laccase, LiP and MnP. It is noteworthy that the degrading capability of LiP when P. chrysosporium was precultivated with barley bran gave a percentage of Poly R-478 decolorization of about 80% in 100 s, whereas control cultures showed a lower percentage, around 20%, after 2 min of the decolorization reaction. 相似文献
6.
Summary The growth of Frankia isolates was monitored by dry weight, total protein and total ATP measurements under different temperature
and pH regimes. Significant correlations (P<0.01) were found among all growth measures which meant that similar general conclusions were reached irrespective of the
study method involved. The assessment of protein was the method of choice for regular assessments of Frankia growth due to
its facility and relatively high sensitivity. The optimum temperature for growth of isolate LDAgp1 and AvcI1 was about 30°C
while for CpI1 it lay between 30° and 35°C. No growth was observed at 40°C but some growth was observed at 10°C with isolate
CpI1 and LDAgp1 over an extended growth period of 39 days. The range of pH favouring growth lay between 6 and 8. The optimum
for LDAgp1 lay between 6.5 and 7, that for AvcI1 and CpI1 is close to 6.5. The pH response was medium dependent. Increases
in biomass were observed for some isolates at 4.6 and above 8.0 on some media. 相似文献
7.
Isothermal titration calorimetry (ITC) was developed for measuring lignin peroxidase (LiP) and manganese peroxidase (MnP) activities of versatile peroxidase (VP) from Bjerkandera adusta. Developing an ITC approach provided an alternative to colorimetric methods that enabled reaction kinetics to be accurately determined. Although VP from Bjerkandera adjusta is a hybrid enzyme, specific conditions of [Mn+2] and pH were defined that limited activity to either LiP or MnP activities, or enabled both to be active simultaneously. MnP activity was found to be more efficient than LiP activity, with activity increasing with increasing concentrations of Mn+2. These properties of MnP were explained by a second metal binding site involved in homotropic substrate (Mn+2) activation. The activation of MnP was also accompanied by a decrease in both activation energy and substrate (Mn) affinity, reflecting a flexible enzyme structure. In contrast to MnP activity, LiP activity was inhibited by high dye (substrate) concentrations arising from uncompetitive substrate inhibition caused by substrate binding to a site distinct from the catalytic site. Our study provides a new level of understanding about the mechanism of substrate regulation of catalysis in VP from B. adjusta, providing insight into a class of enzyme, hybrid class II peroxidases, for which little experimental data is available. 相似文献
8.
Om Prakash Srilakshmi Puliga Lata Sheo Bachan Upadhyay 《Biotechnology and Bioprocess Engineering》2007,12(2):131-135
Urease from dehusked seeds of watermelon was immobilized in 1.5% agarose gel with 53.9% entrapment. There was negligible leaching
(<10% at 4°C) and the same gel membrane could repeatedly be used for seven days. The immobilization exhibited no apparent
change in the optimum pH but there was a significant decrease in the optimum temperature (50°C as compared to 65°C for soluble
urease). The immobilized urease revealed an apparentK
m of 9.3±0.3 mM; 1.2 times lower than the soluble enzyme (11.4±0.2 mM). Unlike soluble enzyme which was inhibited at 200 mM
urea, the immobilized urease was inhibited at 600 mM of urea and above, and about 47% activity was retained at 2 M urea. The
time-dependent thermal inactivation kinetics at 48 and 52°C was found to be biphasic, in which half of the initial activity
was destroyed more rapidly than the remaining half. These gel membranes were also used for estimating the urea content of
the blood samples from the University hospital. The results obtained matched well with those obtained by the usual method
employed in the clinical pathology laboratory. The significance of these observations is discussed. 相似文献
9.
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
10.
Production of hydrogen from marine macro-algae biomass using anaerobic sewage sludge microflora 总被引:1,自引:0,他引:1
Jae-Il Park Jinwon Lee Sang Jun Sim Jae-Hwa Lee 《Biotechnology and Bioprocess Engineering》2009,14(3):307-315
Hydrogen was produced from various marine macro-algae (seaweeds) through anaerobic fermentation using an undefined bacterial
consortium. In this study, anaerobic fermentation from various marine macro-algae for Ulva lactuca, Porphyra tenera, Undaria pinnatifida, and Laminaria japonica was studied. From this analysis Laminaria japorica was determined to be the optimum substrate for hydrogen production. When L. japornica was used as the carbon source for enhanced hydrogen production, the optimum fermentation temperature, substrate concentration,
initial pH, and pretreatment condition were determined to be 35°C, 5%, 7.5, and BT120 (Ball mill and thermal treatments at
120°C for 30 min), respectively. In addition, hydrogen production was improved when the sludge was heat-treated at 65°C for
20 min. Under these conditions, about 4,164 mL of hydrogen was produced from 50 g/L of dry algae (L. japonica) for 50 h, with a hydrogen concentration around 34.4%. And the maximum hydrogen production rate and yield were found to be
70 mL/L·h and 28 mL/g dry algae, respectively. 相似文献
11.
Masafumi Oyadomari Hiroaki Shinohara Toru Johjima Hiroyuki Wariishi Hiroo Tanaka 《Journal of Molecular Catalysis .B, Enzymatic》2003,21(4-6):291-297
Electrochemical analysis of lignin peroxidase (LiP) was performed using a pyrolytic graphite electrode coated with peroxidase-embedded tributylmethyl phosphonium chloride membrane. The formal redox potential of ferric/ferrous couples of LiP was −126 mV (versus SHE), which was comparable with that of manganese peroxidase (MnP) and horseradish peroxidase (HRP). Yet, only LiP is capable of oxidizing non-phenolic substrates with a high redox potential. Since with decreasing pH, the redox potential increased, an incredibly low pH optimum of LiP as peroxidase at 3.0 or lower was proposed as the clue to explain LiP mechanisms. A low pH might be the key for LiP to possess a high redox potential. The pKa values for the distal His in peroxidases were calculated using redox data and the Nernst equation, to be 5.8 for LiP, 4.7 for MnP, and 3.8 for HRP. A high pKa value of the distal His might be crucial for LiP compound II to uptake a proton from the solvent. As a result, LiP is able to complete its catalytic cycle during the oxidation of non-proton-donating substrates. In compensation, LiP has diminished its reactivity toward hydrogen peroxide. 相似文献
12.
Jung Kon Kim Le Nhat Young Nam Chun Si Wouk Kim 《Biotechnology and Bioprocess Engineering》2008,13(4):499-504
The optimum conditions for biological hydrogen production from food waste by Clostridium beijerinckii KCTC 1875 were investigated. The optimum initial pH and fermentation temperature were 7.0 and 40°C, respectively. When the
pH of fermentation was controlled to 5.5, a maximum amount of hydrogen could be obtained. Under these conditions, about 2,737
mL of hydrogen was produced from 50 g COD/L of food waste for 24 h, and the hydrogen content in the biogas was 38%. Hydrogen
production rate and yield were about 108 mL/L·h and 128 mL/g CODdegraded, respectively. High concentrations of acetic (< 5,000 mg/L) or butyric acid (< 3,000 mg/L) significantly inhibited hydrogen
production. 相似文献
13.
Muhammad Asgher Qamar Yasmeen Hafiz Muhammad Nasir Iqbal 《Saudi Journal of Biological Sciences》2013,20(4):347-352
An indigenously isolated white rot fungus, Schizophyllum commune IBL-06 was used to decolorize Solar brilliant red 80 direct dye in Kirk’s basal salts medium. In initial screening study, the maximum decolorization (84.8%) of Solar brilliant red 80 was achieved in 7 days shaking incubation period at pH 4.5 and 30 °C. Different physical and nutritional factors including pH, temperature and fungal inoculum density were statistically optimized through Completely Randomized Design (CRD), to enhance the efficiency of S. commune IBL-06 for maximum decolorization of Solar brilliant red 80 dye. The effects of inexpensive carbon and nitrogen sources were also investigated. Percent dye decolorization was determined by a reduction in optical density at the wavelength of maximum absorbance (λmax, 590 nm). Under optimum conditions, the S. commune IBL-06 completely decolorized (100%) the Solar brilliant red 80 dye using maltose and ammonium sulfate as inexpensive carbon and nitrogen sources, respectively in 3 days. S. commune IBL-06 produced the three major ligninolytic enzymes lignin peroxidase (LiP), manganase peroxidase (MnP) and lacaase (Lac) during the decolorization of Solar brilliant red 80. LiP was the major enzyme (944 U/mL) secreted by S. commune IBL-06 along with comparatively lower activities of MnP and Laccase. 相似文献
14.
Tremacoldi C.R. Watanabe N.K. Carmona E.C. 《World journal of microbiology & biotechnology》2004,20(6):639-642
The production of extracellular acid proteases from Aspergillus clavatus was evaluated in a culture filtrate medium, with different carbon and nitrogen sources. The fungus was cultivated at three
different temperatures during 10 days. The proteolytic activity was determined on haemoglobin pH 5.0 at 37 °C. The highest
acid proteolytic activity (80 U/ml) was observed in culture medium containing glucose and gelatin at 1%(w/v) at 30 °C at the
third day of incubation. Cultures developed in Vogel medium with glucose at 2%(w/v) showed at about 45% of proteolytic activity
when compared to the cultures with 1% of the same sugar. The optimum pH of enzymatic activity was 2.0 and the enzyme was stable
at pH values ranging from 2.0 to 4.0. The optimum temperature was 40 °C and the half-lives at 40, 45 and 50 °C were 30, 10
and 5 min, respectively.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
15.
Masahiro Mori Ehsan Ali Dongning Du Enoch Y. Park 《Biotechnology and Bioprocess Engineering》2009,14(2):193-201
The aim of this study was to improve the production of an extracellular alkaline lipase from Alcaligenes sp. (ATCC 31371) by optimization of the culture medium, for economic production of biodiesel from waste vegetable oil. A
number of carbon sources including different types of starch, sugar, sugar alcohol, organic acids, and surfactants were investigated.
Polyoxyethylene (20) sorbitan tristearate, whose side chain is stearic acid, was the most effective carbon source for lipase
production. Box-Behnken experimental design was used for three factors (soy protein, sodium nitrate, and stearic acid) and
the optimal composition for maximum lipase production (1.7-fold enhancement) was established as soy protein 4.07%, sodium
nitrate 0.17%, and stearic acid 0.28% at 28°C with an agitation rate of 220 rpm for 24 h. The enzyme was purified to homogeneity
and the recovery of the lipase activity was 7.8% with a 30-fold purification. The estimated molecular size of the protein
determined by SDS-PAGE was 33 kDa. The optimum pH and temperature of the purified lipase was 8.5 and 40°C, respectively. The
purified enzyme was stable in the pH range of 6.0 and 9.5 and in the temperature range of 20 and 50°C. 相似文献
16.
Properties of the extracellular amylase produced by the psychrotrophic bacterium, Arthrobacter psychrolactophilus, were determined for crude preparations and purified enzyme. The hydrolysis of soluble starch by concentrated crude preparations
was found to be a nonlinear function of time at 30 and 40 °C. Concentrates of supernatant fractions incubated without substrate
exhibited poor stability at 30, 40, or 50 °C, with 87% inactivation after 21 h at 30 °C, 45% inactivation after 40 min at
40 °C and 90% inactivation after 10 min at 50 °C. Proteases known to be present in crude preparations had a temperature optimum
of 50 °C, but accounted for a small fraction of thermal instability. Inactivation at 30, 40, or 50 °C was not slowed by adding
20 mg/ml bovine serum albumin or protease inhibitor cocktail to the preparations or the assays to protect against proteases.
Purified amylase preparations were almost as thermally sensitive in the absence of substrate as crude preparations. The temperature
optimum of the amylase in short incubations with Sigma Infinity Amylase Reagent was about 50 °C, and the amylase required
Ca+2 for activity. The optimal pH for activity was 5.0–9.0 on soluble starch (30 °C), and the amylase exhibited a K
m with 4-nitrophenyl-α-D-maltoheptaoside-4,6-O-ethylidene of 120 μM at 22 °C. The amylase in crude concentrates initially hydrolyzed raw starch at 30 °C at about the same
rate as an equal number of units of barley α-amylase, but lost most of its activity after only a few hours. 相似文献
17.
Zhiqiang Wu Guoliang Jiang Peng Xiang Honglei Xu 《International journal of peptide research and therapeutics》2008,14(2):113-120
An anionic trypsin (TRY-EP) was purified from North Pacific krill (Euphausia pacifica) by ammonium sulfate precipitation, ion-exchange and gel-filtration chromatography. The purified enzyme was identified as
a trypsin by LC-ESI-MS/MS analysis. The relative molecular mass of TRY-EP was 33 kDa, with isoelectric point of 4.5. The histidine,
tryptophan, arginine, lysine, aspartic acid and glutamic acid residues were functional groups to TRY-EP. TRY-EP was activated
by Ca2+ and Mg2+ and inhibited by some heavy metal ions (Zn2+, Cu2+, Pb2+ and Hg2+), organic solvents (ethanol, glycerin, DMSO and acetone) and specific trypsin inhibitors (benzamidine, CEOM, SBTI and TLCK).
TRY-EP was active over a wide pH (6.0–11.0) and temperature (10–70°C) range, with optimum of pH 9.0 and 40–50°C. TRY-EP was
stable between pH 6.0 and 11.0 and below 30°C. Compared with some trypsins from the Temperate and Tropical Zone organisms,
TRY-EP and other trypsins from the Frigid Zone organisms have higher affinity to substrate and 2–42-fold physiological efficiency. 相似文献
18.
Potential of ligninolytic enzymatic complex produced by white‐rot fungi from genus Trametes isolated from Bulgarian forest soil
下载免费PDF全文
![点击此处可从《Engineering in Life Science》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Ekaterina Krumova Nedelina Kostadinova Jeni Miteva‐Staleva Galina Stoyancheva Boryana Spassova Radoslav Abrashev Maria Angelova 《Engineering in Life Science》2018,18(9):692-701
Because of the crucial role of ligninolytic enzymes in a variety of industrial processes, the demand for a new effective producer has been constantly increasing. Furthermore, information on enzyme synthesis by autochthonous fungal strains is very seldom found. Two fungal strains producing ligninolytic enzymes were isolated from Bulgarian forest soil. They were identified as being Trametes trogii and T. hirsuta. These two strains were assessed for their enzyme activities, laccase (Lac), lignin peroxidase (LiP) and Mn‐dependent peroxidase (MnP) in culture filtrate depending on the temperature and the type of nutrient medium. T. trogii was selected as the better producer of ligninolytic enzymes. The production process was further improved by optimizing a number of parameters such as incubation time, type of cultivation, volume ratio of medium/air, inoculum size and the addition of inducers. The maximum activities of enzymes synthesized by T. trogii was detected as 11100 U/L for Lac, 2.5 U/L for LiP and 4.5 U/L for MnP after 14 days of incubation at 25°C under static conditions, volume ratio of medium/air 1:6, and 3 plugs as inoculum. Among the supplements tested, 5% glycerol increased Lac activity to a significant extent. The addition of 1% veratryl alcohol had a positive effect on MnP. 相似文献
19.
M. Vidyasagar S. Prakash S. K. Jayalakshmi K. Sreeramulu 《World journal of microbiology & biotechnology》2007,23(5):655-662
An extremely halophilic Chromohalobacter sp. TVSP101 was isolated from solar salterns and screened for the production of extracellular halothermophilic protease.
Identification of the bacterium was done based upon biochemical tests and the 16S rRNA sequence. The partially purified enzyme
displayed maximum activity at pH 8 and required 4.5 M of NaCl for optimum proteolytic activity. In addition, this enzyme was
thermophilic and active in broad range of temperature 60–80°C with 80°C as optimum. The Chromohalobacter sp. required 4 M NaCl for its optimum growth and protease secretion and no growth was observed below 1 M of NaCl. The initial
pH of the medium for growth and enzyme production was in the range 7.0–8.0 with optimum at pH 7.2. Various cations at 1 mM
concentration in the growth medium had no significant effect in enhancing the growth and enzyme production but 0.5 M MgCl2 concentration enhanced enzyme production. Casein or skim milk powder 1% (w/v) along with 1% peptone proved to be the best
nitrogen sources for maximum biomass and enzyme production. The carbon sources glucose and glycerol repressed the protease
secretion. Immobilization of whole cells in absence of NaCl proved to be useful for continuous production of halophilic protease. 相似文献
20.
Kim Jong Deog Seo Hyo Jin Hayashi Kiyoshi 《Biotechnology and Bioprocess Engineering》2009,14(3):266-273
In order to create novel β-glucosidase constructs, 8 kinds of chimeric β-glucosidases were constructed using overlapping polymerase
chain reaction (PCR) based on Cellvibrio gilvus (CG) and Thermotoga maritima (TM) genes. Two kinds of novel chimeric β-glucosidases (No. 6 and No. 8 type) were selected and their properties characterized.
SDS-PAGE analysis showed that both constructs had a molecular mass of 80 kDa. The optimum pH of No. 6 chimeric β-glucosidase
was found to be 3.0 and 5.0, showing varying maximum activity according to the buffer used. No. 8 chimeric enzyme was found
to be optimally active at a pH of 4.5 and the optimum temperature of No.6 and No.8 chimeric β-glucosidases was reported to
be 60°C, respectively. The Km values of both novel chimeric enzymes were calculated to be 0.012 mM and 0.0082 mM, respectively
and the characteristics of the novel chimeric enzymes were to lie between those of the parental enzymes. 相似文献