共查询到20条相似文献,搜索用时 93 毫秒
1.
Michelin M Ruller R Ward RJ Moraes LA Jorge JA Terenzi HF Polizeli Mde L 《Journal of industrial microbiology & biotechnology》2008,35(1):17-25
An extracellular glucoamylase produced by Paecilomyces variotii was purified using DEAE-cellulose ion exchange chromatography and Sephadex G-100 gel filtration. The purified protein migrated
as a single band in 7% PAGE and 8% SDS-PAGE. The estimated molecular mass was 86.5 kDa (SDS-PAGE). Optima of temperature and
pH were 55 °C and 5.0, respectively. In the absence of substrate the purified glucoamylase was stable for 1 h at 50 and 55 °C,
with a t
50 of 45 min at 60 °C. The substrate contributed to protect the enzyme against thermal denaturation. The enzyme was mainly activated
by manganese metal ions. The glucoamylase produced by P. variotii preferentially hydrolyzed amylopectin, glycogen and starch, and to a lesser extent malto-oligossacarides and amylose. Sucrose,
p-nitrophenyl α-d-maltoside, methyl-α-d-glucopyranoside, pullulan, α- and β-cyclodextrin, and trehalose were not hydrolyzed. After 24 h, the products of starch hydrolysis,
analyzed by thin layer chromatography, showed only glucose. The circular dichroism spectrum showed a protein rich in α-helix.
The sequence of amino acids of the purified enzyme VVTDSFR appears similar to glucoamylases purified from Talaromyces emersonii and with the precursor of the glucoamylase from Aspergillus oryzae. These results suggested the character of the enzyme studied as a glucoamylase (1,4-α-d-glucan glucohydrolase). 相似文献
2.
Corynebacterium glutamicum is an important microorganism in the industrial production of amino acids. We engineered a strain of C. glutamicum that secretes α-amylase from Streptococcus bovis 148 (AmyA) for the efficient utilization of raw starch. Among the promoters and signal sequences tested, those of cspB from C. glutamicum possessed the highest expression level. The fusion gene was introduced into the homoserine dehydrogenase gene locus on the
chromosome by homologous recombination. L-Lysine fermentation was conducted using C. glutamicum secreting AmyA in the growth medium containing 50 g/l of raw corn starch as the sole carbon source at various temperatures
in the range 30 to 40°C. Efficient L-lysine production and raw starch degradation were achieved at 34 and 37°C, respectively. The α-amylase activity using raw
corn starch was more than 2.5 times higher than that using glucose as the sole carbon source during L-lysine fermentation. AmyA expression under the control of cspB promoter was assumed to be induced when raw starch was used as the sole carbon source. These results indicate that efficient
simultaneous saccharification and fermentation of raw corn starch to L-lysine were achieved by C. glutamicum secreting AmyA using the cspB promoter and signal sequence. 相似文献
3.
We engineered a Corynebacterium glutamicum strain displaying α-amylase from Streptococcus bovis 148 (AmyA) on its cell surface to produce amino acids directly from starch. We used PgsA from Bacillus subtilis as an anchor protein, and the N-terminus of α-amylase was fused to the PgsA. The genes of the fusion protein were integrated
into the homoserine dehydrogenase gene locus on the chromosome by homologous recombination. l-Lysine fermentation was carried out using C. glutamicum displaying AmyA in the growth medium containing 50 g/l soluble starch as the sole carbon source. We performed l-lysine fermentation at various temperatures (30–40°C) and pHs (6.0–7.0), as the optimal temperatures and pHs of AmyA and
C. glutamicum differ significantly. The highest l-lysine yield was recorded at 30°C and pH 7.0. The amount of soluble starch was reduced to 18.29 g/l, and 6.04 g/l l-lysine was produced in 24 h. The l-lysine yield obtained using soluble starch as the sole carbon source was higher than that using glucose as the sole carbon
source after 24 h when the same amount of substrates was added. The results shown in the current study demonstrate that C. glutamicum displaying α-amylase has a potential to directly convert soluble starch to amino acids. 相似文献
4.
Sørensen HR Jørgensen CT Hansen CH Jørgensen CI Pedersen S Meyer AS 《Applied microbiology and biotechnology》2006,73(4):850-861
A novel α-l-arabinofuranosidase (α-AraF) belonging to glycoside hydrolase (GH) family 43 was cloned from Humicola insolens and expressed in Aspergillus oryzae. 1H-NMR analysis revealed that the novel GH43 enzyme selectively hydrolysed (1→3)-α-l-arabinofuranosyl residues of doubly substituted xylopyranosyl residues in arabinoxylan and in arabinoxylan-derived oligosaccharides. The optimal activity of the cloned enzyme was at pH 6.7 and 53 °C. Two other novel α-l-arabinofuranosidases (α-AraFs), both belonging to GH family 51, were cloned from H. insolens and from the white-rot basidiomycete Meripilus giganteus. Both GH51 enzymes catalysed removal of (1→2) and (1→3)-α-l-arabinofuranosyl residues from singly substituted xylopyranosyls in arabinoxylan; the highest arabinose yields were obtained with the M. giganteus enzyme. Combinations (50:50) of the GH43 α-AraF from H. insolens and the GH51 α-AraFs from either M. giganteus or H. insolens resulted in a synergistic increase in arabinose release from water-soluble wheat arabinoxylan in extended reactions at pH 6 and 40 °C. This synergistic interaction between GH43 and GH51 α-AraFs was also evident when a GH43 α-AraF from a Bifidobacterium sp. was supplemented in combination with either of the GH51 enzymes. The synergistic effect is presumed to be a result of the GH51 α-AraFs being able to catalyse the removal of single-sitting (1→2)–α-l-arabinofuranosyls that resulted after the GH43 enzyme had catalysed the removal of (1→3)–α-l-arabinofuranosyl residues on doubly substituted xylopyranosyls in the wheat arabinoxylan. 相似文献
5.
Koseki T Mese Y Nishibori N Masaki K Fujii T Handa T Yamane Y Shiono Y Murayama T Iefuji H 《Applied microbiology and biotechnology》2008,80(6):1007-1013
An α-l-rhamnosidase was purified by fractionating a culture filtrate of Aspergillus kawachii grown on l-rhamnose as the sole carbon source. The α-l-rhamnosidase had a molecular mass of 90 kDa and a high degree of N-glycosylation of approximately 22%. The enzyme exhibited optimal activity at pH 4.0 and temperature of 50 °C. Further, it
was observed to be thermostable, and it retained more than 80% of its original activity following incubation at 60 °C for
1 h. Its T
50 value was determined to be 72 °C. The enzyme was able to hydrolyze α-1,2- and α-1,6-glycosidic bonds. The specific activity
of the enzyme was higher toward naringin than toward hesperidin. The A. kawachii α-l-rhamnosidase-encoding gene (Ak-rhaA) codes for a 655-amino-acid protein. Based on the amino acid sequence deduced from the cDNA, the protein possessed 13 potential
N-glycosylation recognition sites and exhibited a high degree of sequence identity (up to 75%) with the α-l-rhamnosidases belonging to the glycoside hydrolase family 78 from Aspergillus aculeatus and with hypothetical Aspergillus oryzae and Aspergillus fumigatus proteins.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
6.
Feng B Hu W Ma BP Wang YZ Huang HZ Wang SQ Qian XH 《Applied microbiology and biotechnology》2007,76(6):1329-1338
It has been previously reported that a glucoamylase from Curvularia lunata is able to hydrolyze the terminal 1,2-linked rhamnosyl residues of sugar chains at C-3 position of steroidal saponins. In
this work, the enzyme was isolated and identified after isolation and purification by column chromatography including gel
filtration and ion-exchange chromatography. Analysis of protein fragments by MALDI-TOF/TOF™ proteomics Analyzer indicated
the enzyme to be 1,4-alpha-D-glucan glucohydrolase EC 3.2.1.3, GA and had considerable homology with the glucoamylase from Aspergillus oryzae. We first found that the glucoamylase was produced from C. lunata and was able to hydrolyze the terminal rhamnosyl of steroidal saponins. The enzyme had the general character of glucoamylase,
which hydrolyze starch. It had a molecular mass of 66 kDa and was optimally active at 50°C, pH 4, and specific activity of
12.34 U mg of total protein−1 under the conditions, using diosgenin-3-O-α-L-rhamnopyranosyl(1→4)-[α-L-rhamnopyranosyl (1→2)]-β-D-glucopyranoside (compound II) as the substrate. Furthermore, four kinds of commercial glucoamylases from Aspergillus niger were investigated in this work, and they had the similar activity in hydrolyzing terminal rhamnosyl residues of steroidal
saponin.
This project was supported by the National Natural Science Foundation of China (NSFC; 30572333). 相似文献
7.
Arzu Coleri Cihan Birgul Ozcan Cumhur Cokmus 《World journal of microbiology & biotechnology》2009,25(12):2205-2217
We have partially purified and characterized two new thermostable exo-α-1,4-glucosidases (E.C.3.2.1.20) isolated from Geobacillus sp. A333 and thermophilic bacterium A343 strains. A333 α-glucosidase showed optimum activity at 60°C, pH 6.8 and had a value
of 1.38 K
m for the pNPG substrate, whereas these results were found to be 65°C, 7.0 and 0.85, respectively for A343 enzyme. Specificity for 20
different substrates and thin layer chromatography studies demonstrated that the A333 enzyme had high transglycosylation activity,
and A343 had wide substrate specificity. The substrate specificity of A333 α-glucosidase was determined as maltose, dextrin,
turanose, maltotriose, maltopentaose, meltotetraose, maltohexaose and phenyl-α-d-glycopyranoside. On the other hand, the A343 α-glucosidase mostly hydrolyzed dextrin, turanose, maltose, phenyl-α-d-glucopyranoside, maltotriose, maltotetraose, maltopentaose, isomaltose, saccharose and kojibiose by acting α-1,2, α-1,3,
α-1,4 and α-1,6 bonds of these substrates. The relative activites of A333 and A343 enzymes were determined to be 83 and 92%
when incubated at 60°C for 5 h whereas, the pH of 50% inactivation at 60°C for 15 h were determined to be pH 4.5/10.0 and
pH 5.0/10.0, respectively. In addition, the results not only showed that both of the α-glucosidases were stable in a wide
range of pH and temperatures, but were also found to be resistant to most of the denaturing agents, inhibitors and metal ions
tested. With this study, thermostable exo-α-1,4-glucosidases produced by two new thermophilic strains were characterized as
having biotechnological potential in transglycosylation reactions and starch hydrolysis processes. 相似文献
8.
Separation and properties of α-mannosidase and mannanase from the basidiomycetePhellinus abietis 总被引:1,自引:1,他引:0
Proteins of a crude enzyme preparation obtained from the cultivation medium of the basidiomycetePhellinus abietis were separated by gel filtration and ion-exchange chromatography. The preparation contained a minimum of three enzymes capable
of splitting α-d-mannosidic bonds: α-mannosidase, exomannanase, and endomannanase, which were separated. Some properties of the mannanase
complex of the crude enzyme preparation, and of a partially purified α-mannosidase were examined. The mannanase complex exhibited
two pH optima, its temperature optimum being at 46 °C The pH optimum of purified α-mannosidase was at pH 5.0, the temperature
optimum was at 60 °C; the enzyme had a relatively high heat stability. The Km of α-mannosidase forp-nitrophenyl α-d-mannopyranoside was 1.5 x 10−5 M. Pure α-mannosidase did not split mannan. 相似文献
9.
Chao-Hsun Yang Yu-Chun Huang Cheng-Yu Chen Chia-Ying Wen 《Journal of industrial microbiology & biotechnology》2010,37(4):401-406
A gene encoding the thermostable raw starch digesting α-amylase in Thermobifida fusca NTU22 was amplified by PCR, sequenced and cloned into Pichia pastoris X-33 host strain using the vector pGAPZαA, allowing constitutive expression and secretion of the protein. Recombinant expression
resulted in high levels of extracellular amylase production, as high as 510 U/l in the Hinton flask culture broth. The purified
amylase showed a single band at about 65 kDa by SDS-polyacrylamide gel electrophoresis after being treated with endo-β-N-acetylglycosaminidase H, and this agrees with the predicted size based on the nucleotide sequence. About 75% of the original
activity remained after heat treatment at 60°C for 3 h. The optimal pH and temperature of the purified amylase were 7.0 and
60°C, respectively. The purified amylase exhibited a high level of activity with raw sago starch. After 48-h treatment, the
DPw of raw sago starch obviously decreased from 830,945 to 378,732. The surface of starch granules was rough, and some granules
displayed deep cavities. 相似文献
10.
Canakci S Belduz AO Saha BC Yasar A Ayaz FA Yayli N 《Applied microbiology and biotechnology》2007,75(4):813-820
The gene encoding an α-l-arabinofuranosidase from Geobacillus caldoxylolyticus TK4, AbfATK4, was isolated, cloned, and sequenced. The deduced protein had a molecular mass of about 58 kDa, and analysis
of its amino acid sequence revealed significant homology and conservation of different catalytic residues with α-l-arabinofuranosidases belonging to family 51 of the glycoside hydrolases. A histidine tag was introduced at the N-terminal
end of AbfATK4, and the recombinant protein was expressed in Escherichia coli BL21, under control of isopropyl-β-D-thiogalactopyranoside-inducible T7 promoter. The enzyme was purified by nickel affinity
chromatography. The molecular mass of the native protein, as determined by gel filtration, was about 236 kDa, suggesting a
homotetrameric structure. AbfATK4 was active at a broad pH range (pH 5.0–10.0) and at a broad temperature range (40–85°C),
and it had an optimum pH of 6.0 and an optimum temperature of 75–80°C. The enzyme was more thermostable than previously described
arabinofuranosidases and did not lose any activity after 48 h incubation at 70°C. The protein exhibited a high level of activity
with p-nitrophenyl-α-l-arabinofuranoside, with apparent K
m and V
max values of 0.17 mM and 588.2 U/mg, respectively. AbfATK4 also exhibited a low level of activity with p-nitrophenyl-β-d-xylopyranoside, with apparent K
m and V
max values of 1.57 mM and 151.5 U/mg, respectively. AbfATK4 released l-arabinose only from arabinan and arabinooligosaccharides. No endoarabinanase activity was detected. These findings suggest
that AbfATK4 is an exo-acting enzyme. 相似文献
11.
O-α-D-Galactopyranosyl-(1→2)-D-chiro-inositol, herein named fagopyritol B1, was identified as a major soluble carbohydrate (40% of total) in buckwheat (Fagopyrum esculentum Moench, Polygonaceae) embryos. Analysis of hydrolysis products of purified compounds and of the crude extract led to the
conclusion that buckwheat embryos have five α-galactosyl D-chiro-inositols: fagopyritol A1 and fagopyritol B1 (mono-galactosyl D-chiro-inositol isomers), fagopyritol A2 and fagopyritol B2 (di-galactosyl D-chiro-inositol isomers), and fagopyritol B3 (tri-galactosyl D-chiro-inositol). Other soluble carbohydrates analyzed by high-resolution gas chromatography included sucrose (42% of total), D-chiro-inositol, myo-inositol, galactinol, raffinose and stachyose (1% of total), but no reducing sugars. All fagopyritols were readily hydrolyzed
by α-galactosidase (EC 3.2.1.22) from green coffee bean, demonstrating α-galactosyl linkage. Retention time of fagopyritol B1
was identical to the retention time of O-α-D-galactopyranosyl-(1→2)-D-chiro-inositol from soybean (Glycine max (L.) Merrill, Leguminosae), suggesting that the α-ga-lactosyl linkage is to the 2-position of D-chiro-inositol. Accumulation of fagopyritol B1 was associated with acquisition of desiccation tolerance during seed development
and maturation in planta, and loss of fagopyritol B1 correlated with loss of desiccation tolerance during germination. Embryos
of seeds grown at 18 °C, a condition that favors enhanced seed vigor and storability, had a sucrose-to-fagopyritol B1 ratio
of 0.8 compared to a ratio of 2.46 for seeds grown at 25 °C. We propose that fagopyritol B1 facilitates desiccation tolerance
and storability of buckwheat seeds.
Received: 21 May 1997 / Accepted: 5 June 1997 相似文献
12.
Psychrotrophic amylolytic bacteria from deep sea sediment of Prydz Bay, Antarctic: diversity and characterization of amylases 总被引:2,自引:0,他引:2
Seventeen psychrotrophic bacteria with cold-adaptive amylolytic, lipolytic or proteolytic activity were isolated from deep
sea sediment of Prydz Bay, Antarctic. They were affiliated with γ-Proteobacteria (12 strains) and gram-positive bacteria (5 strains) as determined by 16S rDNA sequencing. The amylase-producing strains belonged
to genus Pseudomonas, Rhodococcus, and Nocardiopsis. Two Pseudomonas strains, 7193 and 7197, which showed highest amylolytic activity were chosen for further study. The optimal temperatures
for their growth and amylase-producing were between 15 and 20°C. Both of the purified amylases showed highest activity at
40°C and pH 9.0, and retained 50% activity at 5°C. The SDS-PAGE and zymogram activity staining showed that the molecular mass
of strain 7193 and 7197 amylases were about 60 and 50 kDa respectively. The Pseudomonas sp. 7193 amylase hydrolyzed soluble starch into glucose, maltose, maltotriose, and maltotetraose, indicating that it had
both activities of α-amylase and glucoamylase. The product hydrolyzed by Pseudomonas sp. 7197 amylase was meltotetraose. 相似文献
13.
We have cloned a glucansucrase from the type strain of Leuconostoc mesenteroides (NRRL B-1118; ATCC 8293) and successfully expressed the enzyme in Escherichia coli. The recombinant processed enzyme has a putative sequence identical to the predicted secreted native enzyme (1,473 amino
acids; 161,468 Da). This enzyme catalyzed the synthesis of a water-insoluble α-D-glucan from sucrose (K
M 12 mM) with a broad pH optimum between 5.0 and 5.7 in the presence of calcium. Removal of calcium with dialysis resulted
in lower activity in the acidic pH range, effectively shifting the pH optimum to 6.0–6.2. The enzyme was quickly inactivated
at temperatures above approximately 45°C. The presence of dextran offered some protection from thermal inactivation between
room temperature and 40°C but had little effect above 45°C. NMR and methylation analysis of the water-insoluble α-d-glucan revealed that it had approximately equal amounts of α(1 → 3)-linked and α(1 → 6)-linked d-glucopyranosyl units and a low degree of branching. 相似文献
14.
The α-l-arabinosidase, AraB, was induced when Bacillus pumilus ARA was grown at 50°C in a minimal medium containing xylan. A 56-kDa protein with α-l-arabinosidase activity was purified from culture supernatant to gel electrophoretic homogeneity. The optimal activity was
at pH 6.4 and 60°C over a 10-min assay. The purified enzyme was stable over a pH range of 5.2–7.6 and had a 1-h half life
at 70°C. The enzyme released arabinose from oat spelt xylan. Kinetic experiments at 60°C with p-nitrophenyl α-l-arabinofuranoside as substrate gave a K
m, and V
max of 1.05 mM and 240 U per mg of protein. The NH2-terminal amino acid sequence of the enzyme was determined, and its gene araB was subsequently cloned, sequenced, and over-expressed in Escherichia coli. The open reading frame of araB consists of a 1,479-bp fragment encoding a protein of 472 amino acids, which belonged to family 51 of the glycoside hydrolases
with an identity of 67% to the protein encoded by abfB of Bacillus subtilis 168. 相似文献
15.
Ju Hee Kuk Woo Jin Jung Gyung Hyun Jo Kil Yong Kim Ro Dong Park 《World journal of microbiology & biotechnology》2006,22(2):135-139
Summary
N,N′-diacetylchitobiose was produced from chitin as a major hydrolytic product by controlling the ratio of β-N-acetylglucosaminidase to N,N′-diacetylchitobiohydrolase activities in the crude enzyme preparation of Aeromonas sp. GJ-18. When the enzyme preparation was preincubated at 50 °C, β-N-acetylglucosaminidase was nearly inactivated, while the N,N′-diacetylchitobiohydrolase was still active. Thus, the composition of chitin oligosaccharides depended on the preincubation temperature of the crude enzyme preparations. Typically, after 7 days of incubation with the substrate chitin, 78.9 and 56.6% of N,N′-diacetylchitobiose yields were obtained from swollen α-chitin and powdered β-chitin, respectively, with enzyme preparations that had been pretreated at 50 °C for 60 min. 相似文献
16.
A recombinant putative glycoside hydrolase from Caldicellulosiruptor saccharolyticus was purified with a specific activity of 12 U mg−1 by heat treatment and His-Trap affinity chromatography, and identified as a single 56 kDa band upon SDS-PAGE. The native
enzyme is a dimer with a molecular mass of 112 kDa as determined by gel filtration. The enzyme exhibited its highest activity
when debranched arabinan (1,5-α-l-arabinan) was used as the substrate, demonstrating that the enzyme was an endo-1,5-α-l-arabinanase. The K
m, k
cat, and k
cat/K
m values were 18 mg ml−1, 50 s−1, and a 2.8 mg ml−1 s−1, respectively. Maximum enzyme activity was at pH 6.5 and 75°C. The half-lives of the enzyme at 65, 70 and 75°C were 2440,
254 and 93 h, respectively, indicating that it is the most thermostable of the known endo-1,5-α-l-arabinanases. 相似文献
17.
Psychrotolerant Pseudomonas stutzeri strain 7193 capable of producing an extracellular α-amylase was isolated from deep sea sediments of Prydz Bay, Antarctic.
The 59678-Da protein (AmyP) was encoded by 1665-bp gene (amyP). The deduced amino acid sequence was identified with four regions, which are conserved in amylolytic enzymes and form a
catalytic domain, and was predicted to be maltotetraose forming extracellular amylase by using the I-TASSER online server.
Purification of AmyP amylases from both the recombinant of Escherichia coli Top 10 F′ and strain 7193 was conducted. Biochemical characterization revealed that the optimal amylase activity was observed
at pH 9.0 and temperature 40°C. The enzymes were unstable at temperatures above 30°C, and only retain half of their highest
activity after incubation at 60°C for 5 min. Thin-layer chromatography analysis of the products of the amylolytic reaction
showed the presence of maltotetraose, maltotriose, maltose and glucose in the starch hydrolysate. 相似文献
18.
Canakci S Kacagan M Inan K Belduz AO Saha BC 《Applied microbiology and biotechnology》2008,81(1):61-68
The gene, AbfAC26Sari, encoding an α-l-arabinofuranosidase from Anoxybacillus kestanbolensis AC26Sari, was isolated, cloned, sequenced, and characterizated. On the basis of amino acid sequence similarities, this 57-kDa
enzyme could be assigned to family 51 of the glycosyl hydrolase classification system. Characterization of the purified recombinant
α-l-arabinofuranosidase produced in Escherichia coli BL21 revealed that it is active at a broad pH range (pH 4.5 to 9.0) and at a broad temperature range (45–85°C) and it has
an optimum pH of 5.5 and an optimum temperature of 65°C. Kinetic experiment at 65°C with p-nitrophenyl α-l-arabinofuranoside as a substrate gave a V
max and K
m values of 1,019 U/mg and 0.139 mM, respectively. The enzyme had no apparent requirement of metal ions for activity, and its
activity was strongly inhibited by 1 mM Cu2+ and Hg2+. The recombinant arabinofuranosidase released l-arabinose from arabinan, arabinoxylan, oat spelt xylan, arabinobiose, arabinotriose, arabinotetraose, and arabinopentaose.
Endoarabinanase activity was not detected. These findings suggest that AbfAC26Sari is an exo-acting enzyme. 相似文献
19.
Amylase activity ofTorulopsis ingeniosa Di Menna 总被引:1,自引:0,他引:1
Torulopsis ingeniosaDi Menna was found to possess an α-amylase strongly attached to the cell wall, its pH optimum being at 5.5, optimum temperature at
50 °C, highly sensitive to thermal inactivation. The enzyme was found to be induced by starch but the synthesis is not subject
to a glucose effect. 相似文献
20.
S. K. Soni I. K. Sandhu K. S. Bath U. C. Banerjee P. R. Patnaik 《Folia microbiologica》1996,41(3):243-248
A strain of starch-assimilating yeast,Saccharomycopsis capsularis, isolated from Indian cereal-based fermented foods, produced significant levels of extracellular α-amylase and glucoamylase.
The enzymes reached their peak activities during the stationary phase at the end of the 5th and 4th day of cultivation, respectively.
The amylase yields were maximized by a proper choice of carbon and nitrogen sources, starting pH of the culture medium and
growth temperature. High activities of the enzymes were obtained through inexpensive agricultural commodities, such as wheat
bran and corn meal as carbon sources, and defatted soybean meal and peanut meal as nitrogen sources. A temperature of 28–32°C
and an initial pH of 4.5–5.0 were optimum. The crude amylase mixture could liquefy and saccharify a 1% starch solution completely
in 24 h at 50°C. 相似文献