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1.
A fungal strain, marked as ECU0913, producing high activities of both cellulase and xylanase was newly isolated from soil
sample collected near decaying straw and identified as Penicillium sp. based on internal transcribed spacer sequence homology. The cultivation of this fungus produced both cellulase (2.40 FPU/ml)
and xylanase (241 IU/ml) on a stepwisely optimized medium at 30 °C for 144 h. The cellulase and xylanase from Penicillium sp. ECU0913 was stable at an ambient temperature with half-lives of 28 and 12 days, respectively. Addition of 3 M sorbitol
greatly improved the thermostability of the two enzymes, with half-lives increased by 2.3 and 188-folds, respectively. Catalytic
performance of the Penicillium cellulase and xylanase was evaluated by the hydrolysis of corn stover pretreated by steam explosion. With an enzyme dosage
of 50 FPU/g dry substrate, the conversions of cellulose and hemicellulose reached 77.2% and 47.5%, respectively, without adding
any accessory enzyme. 相似文献
2.
Daniel Luciano Falkoski Valéria Monteze Guimarães Maíra Nicolau de Almeida Acelino Couto Alfenas Jorge Luiz Colodette Sebastião Tavares de Rezende 《Applied biochemistry and biotechnology》2012,166(6):1586-1603
The aim of this work was to evaluate the biochemical features of the white-rot fungi Pycnoporus sanguineus cellulolytic complex and its utilization to sugarcane bagasse hydrolysis. When cultivated under submerged fermentation using
corn cobs as carbon source, P. sanguineus produced high FPase, endoglucanase, β-glucosidase, xylanase, mannanase, α-galactosidase, α-arabinofuranosidase, and polygalacturonase
activities. Cellulase activities were characterized in relation to pH and temperature. β-Glucosidase and FPase activities
were higher at 55 °C, pH 4.5, and endoglucanase activity was higher at 60 °C, in a pH range of 3.5–4.0. All cellulase activities
were highly stable at 40 and 50 °C through 48 h of pre-incubation. Crude enzymatic extract from P. sanguineus was applied in a saccharification experiment using acid-treated and alkali-treated sugarcane bagasse as substrate, and the
hydrolysis yields were compared to that obtained by a commercial cellulase preparation. Reducing sugar yields of 60.4% and
64.0% were reached when alkali-treated bagasse was hydrolyzed by P. sanguineus extract and commercial cellulase, respectively. Considering the glucose production, it was observed that P. sanguineus extract and commercial cellulase ensured yields of 22.6% and 36.5%, respectively. The saccharification of acid-treated bagasse
was lower than that of alkali-treated bagasse regardless of the cellulolytic extract. The present work showed that P. sanguineus has a great potential as an enzyme producer for biomass saccharification. 相似文献
3.
de Almeida MN Guimarães VM Bischoff KM Falkoski DL Pereira OL Gonçalves DS de Rezende ST 《Applied biochemistry and biotechnology》2011,165(2):594-610
The aim of this work was to have cellulase activity and hemicellulase activity screenings of endophyte Acremonium species (Acremonium zeae EA0802 and Acremonium sp. EA0810). Both fungi were cultivated in submerged culture (SC) containing l-arabinose, d-xylose, oat spelt xylan, sugarcane bagasse, or corn straw as carbon source. In solid-state fermentation, it was tested as
carbon source sugarcane bagasse or corn straw. The highest FPase, endoglucanase, and xylanase activities were produced by
Acremonium sp. EA0810 cultivated in SC containing sugarcane bagasse as a carbon source. The highest β-glucosidase activity was produced
by Acremonium sp. EA0810 cultivated in SC using d-xylose as carbon source. A. zeae EA0802 has highest α-arabinofuranosidase and α-galactosidase activities in SC using xylan as a carbon source. FPase, endoglucanase,
β-glucosidase, and xylanase from Acremonium sp. EA0810 has optimum pH and temperatures of 6.0, 55 °C; 5.0, 70 °C; 4.5, 60 °C; and 6.5, 50 °C, respectively. α-Arabinofuranosidase
and α-galactosidase from A. zeae EA0802 has optimum pH and temperatures of 5.0, 60 °C and 4.5, 45 °C, respectively. It was analyzed the application of Acremonium sp. EA0810 to hydrolyze sugarcane bagasse, and it was achieved 63% of conversion into reducing sugar and 42% of conversion
into glucose. 相似文献
4.
Jayashree S Lalitha R Vadivukkarasi P Kato Y Seshadri S 《Applied biochemistry and biotechnology》2011,164(5):666-680
Pink pigmented facultative methylotrophs (PPFM) isolated from water samples of Cooum and Adyar rivers in Chennai and soil
samples of forests located in various districts of Tamil Nadu, India were screened for cellulase production using carboxymethylcellulose
agar (CMC agar) medium. The strains showed wide variations in the production of clearing zones around the colonies on CMC
agar medium flooded with Congo red. CMCase and filter paper assays were used to quantitatively measure the cellulase activity
of 13 PPFM strains. Among the strains, Methylobacterium gregans, MNW 60, MHW 109, MSF 34, and MSF 40 showed cellulolytic activity ranging from 0.73 to 1.16 U mL−1 with wide temperature (35–65°C) and pH (5 to 8) tolerance. SDS-PAGE analysis of the crude enzyme of PPFM strain MNW 60 exhibited
several protein bands, and zymogram analysis revealed two dimeric cellulase bands with molecular mass of ~92 and 42 kDa. Scanning
electron microscopic studies revealed significant morphological differences between the cells grown in normal and CMC amended
medium. The strain MNW 60 was identified as Methylobacterium sp. based on biochemical, physiological, and morphological analyses, and the methylotrophic nature was authenticated by the
presence of mxaF gene, encoding methanol dehydrogenase as a key indicator enzyme of methylotrophs, with 99% similarity to Methylobacterium lusitanum. With the 16S ribosomal RNA sequence showing 97% similarity to M. lusitanum strain MP2, this can be proposed as a novel taxon of the genus Methylobacterium. The study forms the first detailed report on the extracellular cellulase production by pink pigmented Methylobacterium sp., and it is expected that this might be the basis for further studies on cellulase production by PPFMs to explore the
molecular mechanism, strain improvement, and large-scale cellulase production for its application. 相似文献
5.
6.
Taibi Z Saoudi B Boudelaa M Trigui H Belghith H Gargouri A Ladjama A 《Applied biochemistry and biotechnology》2012,166(3):663-679
An extracellular thermostable xylanase from a newly isolated thermophilic Actinomadura sp. strain Cpt20 was purified and characterized. Based on matrix-assisted laser desorption–ionization time-of-flight mass
spectrometry analysis, the purified enzyme is a monomer with a molecular mass of 20,110.13 Da. The 19 residue N-terminal sequence
of the enzyme showed 84% homology with those of actinomycete endoxylanases. The optimum pH and temperature values for xylanase
activity were pH 10 and 80 °C, respectively. This xylanase was stable within a pH range of 5–10 and up to a temperature of
90 °C. It showed high thermostability at 60 °C for 5 days and half-life times at 90 °C and 100 °C were 2 and 1 h, respectively.
The xylanase was specific for xylans, showing higher specific activity on soluble oat-spelt xylan followed by beechwood xylan.
This enzyme obeyed the Michaelis–Menten kinetics, with the K
m and k
cat values being 1.55 mg soluble oat-spelt xylan/ml and 388 min−1, respectively. While the xylanase from Actinomadura sp. Cpt20 was activated by Mn2+, Ca2+, and Cu2+, it was, strongly inhibited by Hg2+, Zn2+, and Ba2+. These properties make this enzyme a potential candidate for future use in biotechnological applications particularly in
the pulp and paper industry. 相似文献
7.
S. Shanmughapriya G. Seghal Kiran Joseph Selvin T. Anto Thomas C. Rani 《Applied biochemistry and biotechnology》2010,162(3):625-640
Marinobacter sp. (MSI032) isolated from the marine sponge Dendrilla nigra was optimized for the production of extracellular cellulolytic enzyme (CMCase) by submerged fermentation. Initial experiments
showed that the culture medium containing 1% maltose as carbon source and 1% peptone and casein as nitrogen source supported
maximal enzyme production at 27 °C and at a pH of 9.0. Further optimization carried out showed the maximal enzyme production
was supported by the presence of 2% NaCl and 10 mM Zn2+ ions in the production media. The production of enzyme cellulase occurred at 48 h of incubation which proved the importance
of this strain for cellulase production in large scale. Further, the enzyme was purified to 12.5-fold with a 37% yield and
a specific activity of 2,548.75 U/mg. The purified enzyme displayed maximum activity at mesophilic temperature (27–35 °C)
and at a broad pH range with optimal activity at pH 9.0. The purified enzyme was stable even at a higher alkaline pH of 12.0
which is greater than the pH stability that has not been reported in any of the cellulolytic isolates studied so far. Thus,
from the present study, it is crucial that, instead of exploring the thermophilic resource that is limited in natural environments,
the mesophilic bacteria that occurs commonly in nature can be added up to the database of cellulolytic bacteria. Thus, it
is possible that a wide diversity of mesophilic bacteria associated with marine sponges opens up a new doorstep for the degradation
of cellulosic waste material for the production of liquid fuels. This is the first report elucidating the prospects of sponge-associated
marine bacterium for the production of extracellular alkaline cellulase. 相似文献
8.
Bing Li Jiqiang Guo Wenfu Chen Xiaoyi Chen Ligang Chen Zhiwen Liu Xianzhen Li 《Applied biochemistry and biotechnology》2009,159(1):24-32
A novel endoxanthanase was produced and isolated from the culture of Microbacterium sp. XT11 growing on xanthan. Optimum pH and temperature for the enzyme activity were 6.0 and 35–40 °C, respectively. The
endoxanthanase cleaves the backbone endo-β-1,4-glucosidic linkage of the xanthan molecule, which is specific to the intact
xanthan. However, the lyase-treated xanthan or carboxymethyl cellulose could not be cleaved by endoxanthanase. 相似文献
9.
Bradley A. Saville Mikhail Khavkine Gayathri Seetharam Behzad Marandi Yong-Li Zuo 《Applied biochemistry and biotechnology》2004,113(1-3):251-259
The performance of cellulase and amylase immobilized on siliceous supports was investigated. Enzyme uptake onto the support
depended on the enzyme source and immobilization conditions. For amylase, the uptake ranged between 20 and 60%, and for cellulase,
7–10%. Immobilized amylase performance was assessed by batch kinetics in 100–300 g/L of corn flour at 65°C. Depending on the
substrate and enzyme loading, between 40 and 60% starch conversion was obtained. Immobilized amylase was more stable than
soluble amylase. Enzyme samples were preincubated in a water bath at various temperatures, then tested for activity. At 105°C,
soluble amylase lost ∼55% of its activity, compared with ∼30% loss for immobilized amylase. The performance of immobilized
cellulase was evaluated from batch kinetics in 10 g/L of substrate (shredded wastepaper) at 55°C. Significant hydrolysis of
the wastepaper was also observed, indicating that immobilization does not preclude access to and hydrolysis of insoluble cellulose. 相似文献
10.
Dengeti Shrinivas Gunashekaran Savitha Kumar Raviranjan Gajanan Ramchandra Naik 《Applied biochemistry and biotechnology》2010,162(7):2049-2057
A highly thermostable alkaline xylanase was purified to homogeneity from culture supernatant of Bacillus sp. JB 99 using DEAE-Sepharose and Sephadex G-100 gel filtration with 25.7-fold increase in activity and 43.5% recovery.
The molecular weight of the purified xylanase was found to be 20 kDA by SDS-PAGE and zymogram analysis. The enzyme was optimally
active at 70 °C, pH 8.0 and stable over pH range of 6.0–10.0.The relative activity at 9.0 and 10.0 were 90% and 85% of that
of pH 8.0, respectively. The enzyme showed high thermal stability at 60 °C with 95% of its activity after 5 h. The K
m and V
max of enzyme for oat spelt xylan were 4.8 mg/ml and 218.6 μM min−1 mg−1, respectively. Analysis of N-terminal amino acid sequence revealed that the xylanase belongs to glycosyl hydrolase family
11 from thermoalkalophilic Bacillus sp. with basic pI. Substrate specificity showed a high activity on xylan-containing substrate and cellulase-free nature. The hydrolyzed product
pattern of oat spelt xylan on thin-layer chromatography suggested xylanase as an endoxylanase. Due to these properties, xylanase
from Bacillus sp. JB 99 was found to be highly compatible for paper and pulp industry. 相似文献
11.
Garcia-Kirchner O. Muñoz-Aguilar M. Pérez-Villalva R. Huitrón-Vargas C. 《Applied biochemistry and biotechnology》2002,98(1-9):1105-1114
The efficient saccharification of lignocellulosic materials requires the cooperative actions of different cellulase enzyme
activities: exoglucanase, endoglucanase, β-glucosidase, and xylanase. Previous studies with the fungi strains Aureobasidium sp. CHTE-18, Penicillium sp. CH-TE-001, and Aspergillus terreus CH-TE-013, selected mainly because of their different cellulolytic and xylanolytic activities, have demonstrated the capacity
of culture filtrates of cross-synergistic action in the saccharification of native sugarcane bagasse pith. In an attempt to
improve the enzymatic hydrolysis of different cellulosic materials, we investigated a coculture fermentation with two of these
strains to enhance the production of cellulases and xylanases. The 48-h batch experimental results showed that the mixed culture
of Penicillium sp. CH-TE-001 and A. terreus CH-TE-013 produced culture filtrates with high protein content, cellulase (mainly β-glucosidase), and xylanase activities
compared with the individual culture of each strain. The same culture conditions were used in a simple medium with mineral
salts, corn syrup liquor, and sugarcane bagasse pith as the sole carbon source with moderate shaking at 29°C. Finally, we
compared the effect of the cell-free culture filtrates obtained from the mixed and single fermentations on the saccharification
of different kinds of cellulosic materials. 相似文献
12.
Taechapoempol K Sreethawong T Rangsunvigit P Namprohm W Thamprajamchit B Rengpipat S Chavadej S 《Applied biochemistry and biotechnology》2011,164(2):204-219
The three highest hydrolysis-capacity-value isolates of Bacillus subtilis (A 002, M 015, and F 018) obtained from Thai higher termites, Microcerotermes sp., under different isolation conditions (aerobic, anaerobic, and anaerobic/aerobic) were tested for cellulase activities—FPase,
endoglucanase, and β-glucosidase—at 37 °C and pH 7.2 for 24 h. Their tolerance to an ionic liquid, 1-butyl-3-methylimidazolium
chloride ([BMIM]Cl), was also investigated. The results showed that the isolate M 015 provided the highest endoglucanase activity
whereas the highest FPase and β-glucosidase activities were observed for the isolate F 018. The isolate F 018 also showed
the highest tolerance to [BMIM]Cl in the range of 0.1–1.0 vol.%. In contrast, the isolate A 002 exhibited growth retardation
in the presence of 0.5–1.0 vol.% [BMIM]Cl. 相似文献
13.
Pradnya Deshpande Sajitha Nair Shubhangi Khedkar 《Applied biochemistry and biotechnology》2009,158(3):552-560
Water hyacinth (Eichhornia crassipes), an aquatic weed common to the subtropic/tropical regions, was utilized as an inexpensive lignocellulosic substrate for
production of cellulase by Trichoderma reesei. The effects of process parameters like substrate pretreatment, substrate concentration, initial medium pH, mode of inoculation,
and incubation temperature on cellulase production were investigated. Under optimal conditions, a maximal cellulase activity
of 0.22 ± 0.04 IU/ml (approximately 73.3 IU/g cellulose) was recorded at the end of 15-day incubation period. Specific activity
of the enzyme was 6.25 IU/mg protein. Hydrolysis of 1% substrate (water hyacinth) using crude enzyme dosage of 1.2 IU/g water
hyacinth showed 28.7% saccharification in 1 h. The observations in present study indicate that saccharification of cellulose
from water hyacinth was significantly higher by laboratory-produced cellulase than the commercial blend. 相似文献
14.
Junpei Zhou Huoqing Huang Kun Meng Pengjun Shi Yaru Wang Huiying Luo Peilong Yang Yingguo Bai Bin Yao 《Applied biochemistry and biotechnology》2010,160(5):1277-1292
A bacterial strain, Streptomyces sp. TN119, was isolated from the gut of Batocera horsfieldi larvae and showed xylanolytic activity. A degenerate primer set was designed based on the base usage of G and C in Actinobacteria xylanase-coding sequences belonging to the glycosyl hydrolases family 10 (GH 10), and used to clone the partial xylanase
gene from Streptomyces sp. TN119. A modified thermal asymmetric interlaced (TAIL)-PCR specific for high-GC genes, named GC TAIL-PCR, was developed
to obtain the full-length xylanase gene (xynA119; 1089 bp). Rich in GC content (67.8%), xynA119 encodes a new GH 10 xylanase (XynA119), which shares highest identity (48.8%) with an endo-1,4-β-xylanase from Cellulosimicrobium sp. HY-12. Recombinant XynA119 was expressed in Escherichia coli BL21 (DE3) and purified to electrophoretic homogeneity. The enzyme showed maximal activity at pH 6.5 and 60 °C, was stable
at pH 4.0 to 10.0 and 50 °C, was resistant to most chemicals (except for Cu2+, Mn2+, Ag+, Hg2+ and SDS) and trypsin, and produced simple products. The specific activity, K
m, V
max, and k
cat using oat-spelt xylan as substrate were 57.9 U mg−1, 1.0 mg ml−1, 74.8 μmol min−1 mg−1, and 49.2 s–1, respectively. 相似文献
15.
Pathange Prakash Senigala K. Jayalakshmi Kuruba Sreeramulu 《Applied biochemistry and biotechnology》2010,160(7):1909-1920
An extremely alkaliphilic bacterial strain, Bacillus sp. PPKS-2, was isolated from rice mill effluents and screened for the production of extracellular keratinase. The maximum
production of keratinase occurred after 48 h in shaking culture at pH 11.0 and 37 °C in a medium containing 0.5% soybean flour.
The strain grew and produced alkaline keratinase using chicken feather and horn meal as the sole source of carbon and nitrogen.
An addition of 0.1% soybean flour or feather hydrolysate and sodium sulfite to feather medium increased the production and
complete solubilization of feather took place within 5 days under solid-state fermentation conditions. The partially purified
enzyme displayed maximum activity at pH 11.0 and 60 °C in a broad range of NaCl, 0–16%, and was not inhibited by sodium dodecyl
sulfate (10%), ethylenediaminetetraacetic acid (10 mM), H2O2 (15%), and other commercial detergents. Immobilization of the whole cells proved to be useful for continuous production of
keratinase and feather degradation. The enzyme was effectively used to remove hair from goat hide. The strain PPKS-2 can be
effectively used for solid waste management of poultry feather in submerged as well as solid-state fermentation. 相似文献
16.
Ashok Pandey Simon Joseph L. Ashakumary P. Selvakumar Carlos R. Soccol 《Applied biochemistry and biotechnology》1999,82(2):103-114
A newly isolated mesophilic bacterial strain from dahlia rhizosphere, identified as Staphylococcus sp. and designated as RRL-M-5, was evaluated for inulinase synthesis in submerged cultivation using different carbon sources
individually or in combination with inulin as substrate. Inulin appeared as the most favorable substrate at a 0.5–1.0% concentration.
Media pH influenced the enzyme synthesis by the bacterial strain, which showed an optimum pH at 7.0–7.5. Supplementation of
fermentation medium with external nitrogen (organic and inorganic) showed a mixed impact on bacterial activity of enzyme synthesis.
The addition of soybean meal and corn steep solid resulted in about an 11% increase in enzyme titers. Among inorganic nitrogen
sources, ammonium sulfate was found to be the most suitable. Maximum enzyme activities (446 U/L) were obtained when fermentation
was carried out at 30°C for 24 h with a medium containing 0.5% inulin as a sole carbon source and 0.5% soybean meal as the
nitrogen source. Bacterial inulinase could be a good source for the hydrolysis of inulin for the production of d-fructose. 相似文献
17.
Yeasmin S Kim CH Park HJ Sheikh MI Lee JY Kim JW Back KK Kim SH 《Applied biochemistry and biotechnology》2011,164(3):294-304
Cellulase-free xylanase has potential for its application in the selective removal of hemicellulose from kraft pulp to give
good strength to paper. In this study, a gene (xyn) encoding cellulase activity–free xylanase enzyme (Xyn) was isolated from Paenibacillus polymyxa PPL-3. The xyn gene encoded a protein of 221 amino acids, and the purified Xyn was about 22.5 kDa measured by sodium dodecyl sulfate–polyacrylamide
gel electrophoresis. Moreover, the cellulase activity–free xylanase enzyme (Xyn) was displayed on the cell surface of Saccharomyces cerevisiae EBY100 using Aga2p as an anchor protein. Cell surface display of xylanase enzyme (Xyn) on S. cerevisiae EBY100 was confirmed by immunofluorescence microscopy. Optimum cell surface display of xylanase enzyme (Xyn) was observed
at pH 7 and 40 °C. Therefore, cell surface–displayed xylanase enzyme (Xyn) can be used in the paper industry. 相似文献
18.
An extracellular xylanase produced by a Mexican Aspergillus strain was purified and characterized. Aspergillus sp. FP-470 was able to grow and produce extracellular xylanases on birchwood xylan, oat spelt xylan, wheat straw, and corncob,
with higher production observed on corncob. The strain also produced enzymes with cellulase, amylase, and pectinase activities
on this substrate. A 22-kDa endoxylanase was purified 30-fold. Optimum temperature and pH were 60°C and 5.5, respectively,
and isoelectric point was 9.0. The enzyme has good stability from pH 5.0 to 10.0 retaining >80% of its original activity within
this range. Half-lives of 150 min at 50°C and 6.5 min at 60°C were found. K
m
and activation energy values were 3.8 mg/mL and 26 kJ/mol, respectively, using birch wood xylan as substrate. The enzyme
showed a higher affinity for 4-O-methyl-d-glucuronoxylan with a K
m
of 1.9 mg/mL. The enzyme displayed no activity toward other polysaccharides, including cellulose. Baking trials were conducted
using the crude filtrate and purified enzyme. Addition of both preparations improved bread volume. However, addition of purified
endoxylanase caused a 30% increase in volume over the crude extract. 相似文献
19.
Either the natural biodegradation process or the industrial hydrolytic process requires synergistic interactions between various
cellulases. However, it is sometimes impeded by low hydrolytic rate of existing cellulases and the lack of accessory enzymes.
Herein, the ability of a commercial cellulase (Spezyme CP, from Genencor) to degrade steam explosion-pretreated corn stover
was significantly improved. Firstly, a fungal cellulase producer, Aspergillus fumigatus ECU0811, was isolated from hundreds of soil samples. A 96-deep-well microscale-based platform was developed here to reduce
the labor-intensive screening work and proved to be consistent with macroscale screening work. After optimization of fermentation,
3% corn cob could induce A. fumigatus ECU0811 to yield the highest cellulase production. Based on the high activities of β-glucosidase and xylanase by A. fumigatus ECU0811, 0.91 and 125 U/mg protein, respectively, an enzyme cocktail was composed with a fixed dosage of Spezyme CP (CPCel)
at 14.2 filter paper units (FPU)/g glucan and varied dosages of A. fumigatus cellulase (AFCel). Consequently, the glucan-to-glucose conversion of corn stover was increased from 25.6% in the presence
of CPCel at a dosage of 14.2 FPU/g glucan to 99.5% in the presence of the enzyme cocktail (14.2 FPU CPCel plus 1.21 FPU AFCel
per gram of glucan). On the other side, it reduced the total protein amount of CPCel by as much as tenfold, which extremely
improved the hydrolytic rate of Spezyme CP and reduced its dosage. 相似文献
20.
Nguyen Q. A. Tucker M. P. Boynton B. L. Keller F. A. Schell D. J. 《Applied biochemistry and biotechnology》1998,(1):77-87
Selective thinning of forests in the western United States will generate a large, sustainable quantity of softwood residues
that can be an attractive feedstock for fuel ethanol production. The major species available from thinning of forests in northern
California and the eastern Rocky Mountains include white fir (Abies concolor), Douglas fir (Pseudotsuga menziesii), and Ponderosa pine (Pinus ponderosa). Douglas fir chips were soaked in 0.4% sulfuric acid solution, then pretreated with steam at 200 – 230°C for 1 – 5 min.
After pretreatment, 90 – 95% of the hemicellulose and as much as 20% of the cellulose was solubilized in water, and 90% of
the remaining cellulose can be hydrolyzed to glucose by cellulase enzyme. The prehydrolysates, at as high as 10% total solid
concentration, can be readily fermented by the unadapted yeastSaccharomyces cerevisiae D5A. 相似文献