• Korean Journal of Microbiology
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• v.31 no.2
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• pp.136-140
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• 1993

The A. nidulans expression vector which contained trpC marker gene from A. nidulans was constructed to produce glucoamy]ase. The recombinant plasmid was introduced into auxotrophic mutant A. nidulans B17. Southern blot analysis of the genomic DNA from transformant showed that pKHG2 DNA had integrated into the A. nidulans chromosomes. Northern analysis of the total RNA from transform ant showed that mRNA of glucoamylase gene was synthesized in induction condition. Specific activity of glucoamylase was increased in transform ants. G]ucoamylase was shown to be active in non-denaturing acrylamide gel.

• Applied Biological Chemistry
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• v.31 no.2
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• pp.182-186
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• 1988

The maximal production of aflatoxin $B_1$, and $G_1$ by A. flavus ATCC 15517 was reduced by 98% and 99% respectively, in the mixed culture with A. awamori var. fumeus in comparison with that in the monoculture of A. flavus. An important cause for the reduction in aflatoxin formation was found that A. awamori var. fumeus excreted aflatoxin degrading factor(s) into the medium during the growth which precipitated by the addition of ammonium sulfate $(0{\sim}80%)$.

• Applied Biological Chemistry
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• v.15 no.3
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• pp.199-206
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• 1972

As a study on the konjak mannan-hydrolyzing enzymes from Aspergillus awamori, the culture conditions for enzyme formation, purification and properties of the enzymes and the effect of gamma-irradiation on the enzymatic hydrolysis were investigated. The results are summarized as follows: 1) A strain of A. awamori was selected as having the highest productivity of mannanase among 81 species of molds. 2) The optimum conditions for solid culture on wheat bran were 3 days of culture period, pH 4 of spraying water and 100% addition of tap water. 3) The optimum conditions for shaking culture were 6 days of culture period, addition of 0.1% xylose plus 0.5% konjak mannan and of 0.04% peptone. 4) Konjak mannan-hydrolyzing enzymes were separated into fraction I and fraction II by ammonium sulfate fractionation and DEAE-Sephadex column chromatography. 5) Fractions I and II showed pH optima of 4, pH stability of $3.5{\sim}5$ and $3{\sim}6$ and the extent of hydrolyzing konjak mannan 9% and 50%, respectively. 6) Hydrolysis of konjak mannan by a crude enzyme preparation was partially accerelated by gamma-irradiation of substrate above 0.5 Mrad and the effect was more remarkable by irradiating in wet state than in dry state. 7) Gamma-irradiation of konjak mannan brought about the increase in reducing power and decrease in viscosity and the effect was more remarkable in wet state than in dry state.

• Journal of Microbiology and Biotechnology
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• v.20 no.10
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• pp.1403-1414
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• 2010

Aspergillus awamori BTMFW032, isolated from sea water, produced tannase as an extracellular enzyme under submerged culture conditions. Enzymes with a specific activity of 2,761.89 IU/mg protein, a final yield of 0.51%, and a purification fold of 6.32 were obtained after purification through to homogeneity, by ultrafiltration and gel filtration. SDS-PAGE analyses, under nonreducing and reducing conditions, yielded a single band of 230 kDa and 37.8 kDa, respectively, indicating the presence of six identical monomers. A pI of 4.4 and a carbohydrate content of 8.02% were observed in the enzyme. The optimal temperature was found to be $30^{\circ}C$, although the enzyme was active in the range of $5-80^{\circ}C$. Two pH optima, pH 2 and pH 8, were recorded, although the enzyme was instable at a pH of 8, but stable at a pH of 2.0 for 24 h. Methylgallate recorded maximal affinity, and $K_m$ and $V_{max}$ were recorded at $1.9{\times}10^{-3}$M and 830 ${\mu}Mol$/min, respectively. The impacts of a number of metal salts, solvents, surfactants, and other typical enzyme inhibitors on tannase activity were determined in order to establish the novel characteristics of the enzyme. The gene encoding tannase, isolated from A. awamori, was found to be 1.232 kb, and nucleic acid sequence analysis revealed an open reading frame consisting of 1,122 bp (374 amino acids) of one stretch in the -1 strand. In silico analyses of gene sequences, and a comparison with reported sequences of other species of Aspergillus, indicate that the acidophilic tannase from marine A. awamori differs from that of other reported species.

• The Korean Journal of Food And Nutrition
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• v.18 no.1
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• pp.4-10
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• 2005

Periodate-oxidized soluble starch increased pH stability of Aspergillus awamori a-glucosidase. After incubation for two hours, the enzyme in the absence of oxidized soluble starch was stable in the range of pH 3-7 at 40℃, pH 3-6 at 50℃ and the enzyme in the presence of oxidized soluble starch was stable in the range of pH 3-9 at 40℃, pH 3-8 at 50℃. At 60℃, the enzyme was stable in pH 3-6 regardless of the presence or absence of IO₄-oxidized soluble starch, but when IO₄-oxidized soluble starch existed in pH 5-6, remained activity of the enzyme increased 20% more than when it didn't exist. The enzyme modified with IO₄-oxidized soluble starch remained 70% of activity in pH 9, but native enzyme didn't remain, showing the increase of stability due to modification. In thermal stability, modified enzyme remained 12% at 50℃ and 7% at 80℃. But native enzyme remained 8% at 50℃ and didn't remain at more than 70℃. The result of HPLC analysis revealed the subunit of the enzyme at under pH 2 or over pH 9 was separated or the enzyme was denatured and conjugated. Protein structure of native enzyme was denatured by acidic and basic pH but was stable in the presence of IO₄-oxidized soluble starch.

• Korean Journal of Soil Science and Fertilizer
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• v.46 no.2
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• pp.117-121
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• 2013

Single or co-inoculation of phosphate solubilizing bacterial and fungal strains (Burkholderia anthina and Aspergillus awamori respectively) was performed separately to assess their synergistic and antagonistic interactions and the potential to be used as bio-inoculants. Co-inoculation was found to release the highest content of soluble phosphorus (1253 ${\mu}g\;ml^{-1}$) into the medium, followed by single inoculation of fungal strain (1214 ${\mu}g\;ml^{-1}$) and bacterial strain (997 ${\mu}g\;ml^{-1}$). However, there was no significant difference between single inoculation of fungal strain and co-inoculation of fungal and bacterial strain in terms of the phosphorous release. The highest pH reduction, organic acid production and glucose consumption were observed in the sole A. awamori inoculated culture medium. According to the plant growth promotion bioassays, co-inoculation of the microbial strains resulted in 21% and 43% higher shoot and root growth of the mung bean seedlings respectively as compared to the respective controls. Therefore, co-inoculation of B. anthina and A. awamori showed better performance in stimulating plant growth than that in inoculation of each strain alone. However, assessment period of the present study being short, we recommend in engaging further experimentation under field conditions in order to test the suitability of the strains to be used as bio-inoculants.

• Korean Journal of Microbiology
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• v.41 no.2
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• pp.146-151
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• 2005

To construct an amylolytic industrial strain of Saccharomyces cerevisiae, the glucoamylase cDNA gene (GAl) from Aspergillus awamori was expressed under the control of the alcohol dehydrogenase gene promoter (ADC1p) and integrated into the chromosomes of industrial S. cerevisiae. An integrative cassette lacking bacterial ampicillin resistance gene but containing the GA1 gene, $\delta$ sequences of Ty1 retrotransposon as target sites for homologous recombination and S. cerevisiae aureobasidin A resistance gene (AUR1-C) as the selection marker was constructed to obtain a strain eligible for commercial use. Industrial S. cerevisiae transformed with this 15-integrative cassette efficiently secreted glucoamylase into the medium and grew on starch as the sole carbon source. The transformants were mitotically stable for 100 generations in nonselective medium.

• Journal of Microbiology and Biotechnology
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• v.25 no.11
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• pp.1842-1848
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• 2015

Cyanidin-3-glucoside (C3G) has been known to be more bioavailable than cyanidin-3-rutinoside (C3R), the most abundant anthocyanin in black raspberry (Rubus occidentalis). The aim of this study was to enhance the bioavailability of anthocyanins in black raspberry by cleaving ʟ-rhamnose in C3R using crude enzyme extracts (CEEs) from Aspergillus usamii KCTC 6956, A. awamori KCTC 60380, A. niger KCCM 11724, A. oryzae KCCM 12698, and A. kawachii KCCM 32819. The enzyme activities of the CEEs were determined by a spectrophotometric method using ρ-nitrophenyl-rhamnopyranoside and ρ-nitrophenyl-glucopyranoside. The CEE from A. usamii had the highest α-ʟ-rhamnosidase activity with 2.73 U/ml at 60℃, followed by those from A. awamori and A. niger. When bioconversion of C3R to C3G in black raspberry was analyzed by HPLC-DAD, the CEEs from A. usamii and A. awamori hydrolyzed 95.7% and 95.6% of C3R to C3G, respectively, after 2 h incubation. The CEEs from A. kawachii and A. oryzae did not convert C3R to C3G in black raspberry.

• Applied Biological Chemistry
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• v.40 no.2
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• pp.89-94
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• 1997

In order to reduce energy input in direct ethanol production from raw starch by co-immobilized Aspergillus awamori(A) and Zymomonas mobilis(Z), A-Z 36 culture system which was changed to anaerobic after 36 h of aerobic fermentation without sterilization was investigated. This immobilized cell system can not be carried out under unsterile conditions because of growth of microbial contaminants from original medium. Among some food additives such as sorbic acid, benzoic acid, dehydroacetic acid, p-hydroxybenzoic acid, Vantocil IB and Neupectin-L, Vantocil IB and Neupectin-L were a potent antibacterial agent in A-Z 36 culture cell system and were not affected in hydrolysis of substrate as compared with the case of control. Ethanol yield(6.9 g/l) in system of addition of 0.1% Neupectin-L was slightly higher than that in control(6.4 g/l). When 2% starch was fed five times in fed-batch culture with 0.1% Neupectin-L, ethanol yield and productivity were 34 g/l and 2.0 g/l/day, respectively.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.23 no.2
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• pp.69-76
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• 1990

To substitute the soy-sauce 'koji' used in fish sauce processing with molded sardine meal(MSM) 'koji', the culture conditions of MSM be inoculated with Aspergillus spp. were investigated. To prepare the MSM, Asp. awamori(KFCC. 11439), Asp. guercinus (KFCC. l1595), Asp. niger(KFCC. 11239), Asp. oryzae(KFCC. 32343), and Asp. sojae(KFCC. 11559) were inoculated upon the chopped sardine with $20\%$ (w/w) corn starch after steriling it at $121^{\circ}C$ for 15min. Sporulation time cultured with Asp. spp. at $30^{\circ}C$ was 48hrs and color of mycelium on the surface of MSM inoculated with Asp. awamari and Asp. oryzae were black, that of MSM inoculated with the other strains were yellowish brown. The activity of protease and lipase from the MSM were increased till the 72hrs of culture at $30^{\circ}C$, while the content of trimethylamine was decreased after 96hrs of culture period at same condition with exception of Asp. niger. Asp. oryzae and Asp. sojae showed superior in pro-tease and lipase activity in comparison with the other strains, and maximum activity of protease and lipase of MSM was observed after 72hrs of culture period. The optimum pH and temperature for the activity of MSM inoculated with Asp. oryzae and Asp. sojae were pH 9.0, $30\~35^{\circ}C$ and pH $6\~7$, $35^{\circ}C$, respectively.