• Korean Journal of Food Science and Technology
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• v.45 no.3
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• pp.333-338
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• 2013

Enzymatic activity in germinated cereal grains is important for the saccharification of starch materials. This study was conducted to investigate the amylolytic activities of germinating brown rice and black rice that have different amylose contents. Brown rice and black rice were steeped at room temperature for 24 h and germinated at 20 and $30^{\circ}C$ for 1, 2, and 3 days. ${\alpha}$- and ${\beta}$-Amylase activities in normal brown rice increased very slightly during the 3-day germination period, but the enzymatic activities were slightly higher in low-amylose (waxy type) brown rice. Diastatic power (DP), a measure of starch-saccharifying enzyme, was higher in the germinating brown rice with low amylose than in those with normal amylose content. ${\alpha}$- and ${\beta}$-Amylase activities in black rice increased gradually during germination, and DP of low-amylose black rice appeared to be higher than that of normal brown rice. Amylase activities in brown rice and black rice germinated at $30^{\circ}C$ were higher than those germinated at $20^{\circ}C$. Compared to brown rice, the overall amylolytic activity of germinated black rice was observed to be higher than that of brown rice.

• The Korean Journal of Food And Nutrition
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• v.12 no.2
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• pp.164-169
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• 1999

To develope the scientific preparation method of Dorean traditional rice drink 'Sikhye', effect of malt and commercial amylolytic enzymes in preparation of malt-Sikhye were studied. amylase activity of malt used in this study was 9,725unit/g. In malt-Sikhye preparation effective saccharifying conditions were 4% of malt 20% of rice at 6$0^{\circ}C$ for 5hour. Commercial amylolytic enzymes such as $\beta$-amylase(Bio-zyme ML Himaltosin GL) $\alpha$-amylase(Bokhabhyoso 5000, Teramyl and Fungamyl) and pulluanase(en-zyme CK-20) were not effective in saccharification for Sikhye preperation.

• Korean Journal of Microbiology
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• v.6 no.3
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• pp.81-86
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• 1968

1. Amylolytic enzyme activities of Asp. oryzae and Asp. oryzae var. fulvus using the glucose as the carbon sources increased remarkably according to the decrease of the residual sugars. 2. The amylase productions of Asp. oryzae and Asp. oryzae var. fulvus were increased and enhanced when the organisms lave belen cultured in modified Koji media containing maltose as adaptive substrate. However, being devoid of maltose the level of amylase activities were lower and the begining of the production was prolonged. 3. The effects of C-sources on the amylase production of them were observed. The level of amylase activity varied with C-sources and their concentrations Marked increase of amylase production was afforded by starch and maltose. The effects of citric acid and tartaric acid were little or nothing. 4. Using the sucrose and lactose as the adaptive substrates both strains show the maximum amylolytic enzyme activities at the 3% concentrations of those sugars.

• Microbiology and Biotechnology Letters
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• v.13 no.2
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• pp.129-135
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• 1985

The amylolytic yeasts were isolated from natural sources. Among them, a strain FRI YO-32 was selected as one of the genetically potential microorganisms and was identified as a strain of Hansenula anomala var anomala. Genetic markers were introduced into the isolated haploid strains of the strain FRI YO-32 and Saccharomyces cerevisiae by conventional mutagenic procedures with EMS or MNNG.

• Microbiology and Biotechnology Letters
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• v.44 no.3
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• pp.376-382
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• 2016

The amylolytic enzyme activities of nuruks collected or produced in this study were examined. A maximum α-amylase activity of 24,747.1 ± 777.7 units/mg protein was obtained for a nuruk incubated at a relative humidity of 40% at 30℃. A nuruk matured at a relative humidity of 50% at 25℃ showed the highest glucoamylase acitivity. Among the 98 fungal strains isolated from the nuruk exhibiting the highest amylolytic enzyme activities, 26 strains of Aspergillus oryzae and 18 strains of Rhizopus oryzae were identified. Rhizopus oryzae MBF345 showed an α-amylase activity of 36,724.9 ± 10.2 units/mg protein and a glucoamylase activity of 4,911.8 ± 48.1 SP. These values were 1.7-fold and 1.4-fold greater, respectively, than those of the control strain. Strain MBF345 was deposited as KCTC46312 in the Korean Culture Type Collection.

• Korean Journal of Food Science and Technology
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• v.22 no.3
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• pp.296-299
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• 1990

As an improved preparation method of Shikhae, a tea-bag system containing malt and amylolytic enzymes was developed in which extraction of malt enzymes and saccharification occured efficiently. The amylolytic activity of the malt was increased by adding the mixture of ${\alpha}-amylase$, glucoamylase and glucoisomerase. Malt and the mixture of enzymes were placed in tea-bag $(16{\times}20cm)$, extracted in water at $30-40^{\circ}C$ for 1-2 hours and followed by saccharification of the cooked rice at $60-70^{\circ}C$ for 3-4 hours. In the conventional Shikhae, content of maltose was about 50% and that of oligosaccharides larger than trisaccharides was about 40% of total sugar. The content of monosaccharides such as glucose and fructose was about 95% and this improved method would be effective for increasing the sweetness and the monosaccharide contents in the product.

• Microbiology and Biotechnology Letters
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• v.16 no.2
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• pp.105-110
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• 1988

The production of single cell protein using the amylolytic fusant obtained from cell fusion between Hansenula anomala and Saccharomyces cerevisiae was studied. The fusant12 strain was selected for single cell protein production from starchy materials among five fusants. Optimum nitrogen source and its concentration for the growth of fusant12 were ammonium sulfate and 0.1%, respectively. Optimum concentration of soluble starch and optimum pH of the basal medium were lord and pH 5.6, respectively. Autolysis of fusant12 was effectively carried out by addition of 5% (v/v) ethyl acetate to the cell suspension and liquidization for 30 min before incubation for 24 hr at 3$0^{\circ}C$. Coculture of fusant12 and non-amylolytic yeast, Torulopsis candida YA-l5, resulted in the increase of the mass as compared to the monoculture of fusant12. The cell mass on tapioca medium was increased about 2.5 times as on soluble starch medium. The content of crude protein and nucleic acid of the dry cell were 39% and 5.8%, respectively.

• KSBB Journal
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• v.22 no.2
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• pp.114-118
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• 2007

In this study, an amylase-producing fungus, strain 15 was isolated from soil in order to saccharify food wastes with cellulolytic and amylolytic enzymes. The amylase production cultures were performed in Mandel's medium with 1% rice straw and 1% paper wastes as carbon sources. The strain produced various cellulolytic (FPase 0.25, xylanase 20.09, CMCase 3.15 U/mL-supernatant) and amylolytic ($\alpha$-amylase 1.20, gluco-amylase 0.70, $\beta$-amylase 2.40 U/mL-supernatant) enzymes in Mandel's medium. In 10 L jar fermenter, maximum amylase and FPase activities, 3.25 and 0.23 U/mL, were obtained when the culture was grown at 30$^{\circ}C$, 200 rpm and 0.6 vvm for 3 days. In 100 mL flask level and 10 L jar fermenter, amylase produced by the strain 15 showed similar cellulolytic and amylolytic enzyme activities with Trichoderma inhamatum KSJ1 isolated from rotten woods by previous researcher. The ability of saccharification to food wastes also showed similar degree. However, the isolate 15 appeared to be yellowish in YMEA plate comparing to Trichoderma inhamatum KSJ1 in greenish.

• Korean Journal of Food Science and Technology
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• v.29 no.3
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• pp.581-587
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• 1997

For bifidus fermentation food, gelatinized rice solution was fermented without liquefaction/saccharification by amylolytic Bifidobacterium spp. isolated from Korean. Eighteen amylolytic Bifidobcterium on the starch agar were isolated from 38 Korean and four strains were finally selected as good amylase producers. The most enzyme-producing strain of Bif. sp. FBD-12 secreted extracellular amylase of 0.17 U/mg and intracelluar amylase of 1.8 U/mg. Three strains of Bif. sp. FBD-12, Bif. sp. FBD-16 and Bif. sp. FBD-17 also showed good growth on pH controlled media by HCI/acetic acid to pH 5.0 while Bif. sp. FBD-6 was not so tolerant that viable cell counts reduced to $10^2\;CFU/mL$ times on the media. Initial cell number of $10^6\;CFU/mL$ for those strains reached to $10^9\;CFU/mL$ on the rice medium supplemented with yeast extract (0.2%) and cysteine (0.05%). Ascorbic acid instead of cysteine was added to the medium for improving off-flavour and the best growth was shown at 0.1% addition. Isolated soybean proteins (ISP) of 3% accelerated the growth of the strains. Maximum count of $10^9\;CFU/mL$ reached within 12 hour fermentation on the rice medium with ascorbic acid and isolated soybean protein instead of 32 hours on the cysteine medium, and total acidity increased from 0.5% to 1% on each media. Reducing sugar in the ascorbic acid/ISP cultures generally increased especially 2 mg/mL to 15.5 mg/mL for Bif. sp. FBD-6. From sensory evaluation, the products showed good acceptability so that it suggested possibility of development of bifidus-fermented rice food.

• Microbiology and Biotechnology Letters
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• v.23 no.6
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• pp.737-746
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• 1995

Through the study of identification of filamentous molds isolated from 12 traditional Nuruk, collected from several regions in Korea, 78 strains of Absidia spp., including Absidia corymbifera, Absidia ramosa, and Absidia sp. of which specific names were not identified, 19 strains of Rhizopus spp. including Rhizopus cohnii, Rhizopus arrhizus, and Rhizopus oryzae, 8 strains of Circinella spp., 1 strain of Actinomucor sp., 49 strains of Aspergillus spp., including Aspergillus oryzae, Aspergillus flavus, Aspergillus flavus var. columnaris, Aspergillus wentii, Aspergillus candidus, Aspergillus fumigatus, Aspergillus niger, and Aspergillus foetidus, 2 strains of Cladospoyium spp. and 2 strains Botryotrichum spp., etc. total 159 kinds of filamentous molds were isolated and identified. There were many differences in numbers and distributions of filamentous molds from each Nuruk according to their collected region. Absidia spp. were most frequently isolated from every Nuruk sample. Aspergillus oryzae, Aspergillus candidus, and Rhizopus cohnii showed even distribution. Penicillium sp. and Mucor sp. were not detected. Actinomucor sp., Aspergillus foetidus, Botryotrichum sp., and Cladosporium spp., which have not been reported by far, were found. Amylase activities, pH stability of amylase, and acid productivity of isolated strains were compared.