• Applied Biological Chemistry
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• v.30 no.4
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• pp.305-310
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• 1987

The enzymatic properties of ${\beta}-amylase$ from soybean and sweet potato were compared. The sweet potato enzyme consists of four identical subsunits whereas soybean enzyme has no subunit $structure^{12,\;15)}$. In the denatured state, both enzymes exhibited the same molecular weight on SDS-gel electrophoresis and on gel-filtration analysis. The spectra of circular dichroism revealed that both enzyme have almost same secondary structure but the environment of aromatic side chains are different. The chemical cleavage of soybean and sweet potato ${\beta}-amylases$ at cysteine residues and methionine residues demonstrated the homology of amino acid sequence between the enzymes. The similarity between soybean and sweet potato ${\beta}-amylase$ was also revealed by immunological method. The antibody for soybean enzyme inhibited the activity of sweet potato enzyme but it did not inhibit the activity of wheat, barley and Japanese-raddish ${\beta}-amylases$.

• The Korean Journal of Food And Nutrition
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• v.3 no.2
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• pp.149-160
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• 1990

The soybean $\beta$-amylase ($\alpha$-1, 4-glucan maltohydrolase, EC 3.2.1.2) is composed of seven isozymes(I', I, II, III, IV, V and VI), and isozyme II and IV are the main components among these. The Purification of $\beta$-amylase isozymes from soybean whey were performed by ammonium sulfate fractionation, CM-Sephadex C-50 column chromatography, DEAE-Sephadex chromatography and Gel filtration. The resulted purity of $\beta$-amylase was throughly confirmed by electrophoresis, and then determined its isoelectric point and molecular weight. The results obtained were as follows, 1. Five active fractions of soybean p-amylase were derived on CM-Sephadex C-50 column chromatography. 2. Seven active bands of p-amylase isozymes were detected by isoelectric focusing gel electrophoresis, and their isoelectric points(I' to VI) were 5.07, 5.15, 5.25, 5.40, 5.55, 5.70 and 5.93, respectively. 3. Isozyme II and IV were main components of soybean $\beta$-amylase. 4. The molecular weights of both isozyme II and IV were determined to be 56,000 daltons by the result of SDS polyacrylamide gel electrophoresis. 5. Km values of main isozyme II & IV for amylopectin were determined to be 2.25 mg/ml, which suggest the same function of each isozyme.

• Food Science and Preservation
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• v.8 no.4
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• pp.405-411
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• 2001

This study was conducted to investigate the effect of rice powder m tile enzyme (protease, $\alpha$-amylase, $\beta$-amylase and glucoamylase) activities of soybean meju fermented by Monascus prepureus and Monascus pilosus. The activities of the enzyme in the rice meju and the soybean meju fermented by M. pilosus were higher than those by M. perpureus. Protease activity of powdered rice meju was higher than that of granular rice meju, while $\alpha$-amylase, $\beta$-amylase and glucoamylase activities were higher in granular rice meju. Protease activity in soybean meju fermented by adding of the cultured medium of Monascus strains(CMM) as a seed inocula were higher than those of the rice powder meju, while $\alpha$-amyulase, $\beta$-amylase and glucoamylase activiities were lower than those of soybean meju by CMM. The concentration of rice powder to show maximum protease activity in soybean meju was also 10% against steamed soybean. But $\alpha$-amylase activity of soybean medju by the CMM added 2% powdered rice showed lower but the activity increaed with an increase in powdered rice, whereas $\beta$-amylase and glucoamylase activiities decreased with an increase in powdered rice. Protease activity of soybean meju fermented by 10% rice meju fermented by M. pilo년 as a seed inocula was higher than that of the meju fermented by Aspergillus oryzae, whereas $\beta$-amylase and glucoamylase activities of the soybean meju showed less than 50%.

• The Korean Journal of Food And Nutrition
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• v.7 no.1
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• pp.23-28
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• 1994

Soybean $\beta$-amylase was purified by DEAE-cellulose ion exchange chromatography, Sephadex G-100 gel chromatography, CM Sephadex C-50 ion exchange chromatography and CM Sephadex C-50 ion exchange rechromatography The purified enzyme showed 1, 020 unit/mg of specific activity. The purified enzyme was identified as homogenious by disc PAGE and analysis of reaction product.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.45 no.2
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• pp.139-142
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• 2000

The experiment was carried out to study the variations and geographical distribution of $\beta$-amylase isozyme by isoelectric focusing (IEF) within Korean, Chinese and Japanese soybean land races. In pH 3-10 gel of IEF, the amylase of soybean accessions was separated into low pI group isozymes (TEX>${$Sp_1$}^b$) and high pI group isozymes(${$Sp_1$}^a$). In pH4-6.5 gel, isoelectric points were at 5.07, 5.15, 5.25, 5.40, and 5.94, and h, j, and k bands also were found. The distribution of Sp$_1$$^{a}$ allele (high pI type) was 29.3% in soybean accessions from Korea, 10.1 % in those from China, and 6.9% in Japanese accessions. The percentage of ${$Sp_1$}^a$) allele was the highest in soybean accessions from Kyungsang province (35 %) in Korea, then central China (32 %) in China, and Honshu (10%) in Japan.

• The Korean Journal of Food And Nutrition
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• v.4 no.2
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• pp.161-166
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• 1991

The blocked N-terminus and N-terminal sequence of soybean B-amylase were aetermined by analyzing the acidic peptides derived on peptic digestion of the enzyme. The acidic peptides were separated from the digest on a Dowex 50$\times$2 column(1X5cm) and purified by reversed phase-high performance liquid chromatography(RP-HPLC). The major acidic peptide, PEP-1, was a heptapeptlde. The N-terminal 7 amino acid sequence of soybean B-amylase was deduced to be acetyl-Ala-Thf-Ser-Asp-Ser-Asn-Met- from the results of sequence analysis of PEP-1 and amino acid analysis of other acidic peptides.

• Journal of Environmental Science International
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• v.22 no.6
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• pp.723-732
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• 2013

This study was carried out to investigate changes of protease and amylase activities and nitrogen content in Chungkookjang prepared by Bacillus subtilis S8 and different soybean. Amino-type nitrogen and ammonia-type nitrogen contents increased with an increase in fermentation time and was the highest in black soybean Chungkookjang. The number of viable cells increased up to 24 h of fermentation at all temperatures tested; especially, their levels were the highest at $40^{\circ}C$. Protease activity was the highest in black soybean Chungkookjang. ${\alpha}$-amylase activity increased significantly up to 6 h of fermentation at $30^{\circ}C$ and $40^{\circ}C$ and then maintained constantly. It also increased up to 30-36 h of fermentation at $45^{\circ}C$ and then decreased. ${\beta}$-amylase activity was the highest in black soybean Chungkookjang at $35^{\circ}C$ and $40^{\circ}C$ and in yellow soybean Chungkookjang at $45^{\circ}C$. Production pattern of reducing sugar was similar to that of ${\beta}$-amylase. Amino-type nitrogen, viable cell number and reducing sugar content and ${\beta}$-amylase activity was the highest in Chungkookjang fermented at $40^{\circ}C$. Considering amino-type and ammonia-type nitrogen contents, Chungkookjang fermentation using yellow soybean was favorable. However, the fermentation using black soybean was favorable, considering protease and amylase activities and reducing sugar content.

• Journal of the East Asian Society of Dietary Life
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• v.16 no.4
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• pp.447-452
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• 2006

This study examined the growth and sensory characteristics of soybean sprout cultured at 25$\pm$1$^{\circ}C$ for 4 days with distilled water control and green tea extracted water (0.03% and 0.05%). The proximate composition of soybean sprout in the green-tea water was better than that of the control in ash, protein and fat, while the soybean sprout was especially higher in 0.05% green-tea water. The contents of vitamin C and $\beta$-carotene were higher in soybean sprout in green-tea water than the control. The total free amino acids composition of soybean sprout in green-tea water was better than that of the control, with the highest being obtained in soybean sprout in 0.03% green-tea water. Antioxidative activity was assayed by DPPH radical scavenging ability with spectrophotometer at 514 nm. The soybean sprout in green-tea water was higher than control. The amylase activity of the soybean sprout increased steadily during the first 4 days and that of the control was higher than soybean sprout in green-tea water. The proteinase of soybean sprout steadily increased during 4 day culture. Furthermore, the proteinase activity of soybean sprout in green-tea water was higher than that of the control up to 2 days. Whereas after 3 days, it was the highest in 0.03% green-tea water and then decreased remarkably in 0.05% green-tea water.

• Applied Biological Chemistry
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• v.35 no.4
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• pp.232-236
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• 1992

In order to manufacture of soy paste, Changes of chemical composition and enzyme activity of soybean by different processing method were investigated. The results are summarized as follows: Changes of chemical compositions were; Raw(A) and soaked(B) soybeans contain about 2% of more crude fat than roasted(C) and steamed(D) soybeans, roasted and steamed soybeans contain $1.16{\sim}1.74%$ of more protein than those of raw and soaked soybeans, and Raw and roasted soybeans contain $0.11{\sim}0.41%$ of more crude fiber than those of soaked and steamed soybeans. ${\alpha}-amylase$, ${\beta}-amylase$, protease, lipase activity of raw and soaked soybeans were $2{\sim}5$ folds higher than those of roasted and steamed soybeans. Trypsin inhibitor activity of raw, soaked, roasted and steamed soybeans was indicated 56.7%, 42.9%, 32.9% and 20.8% in the order, respectively.

• Journal of Microbiology and Biotechnology
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• v.14 no.6
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• pp.1196-1199
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• 2004

A bacterium, isolated from rabbit's waste and identified as Cellulomonas sp., had cellulase and thermostable $\alpha$-amylase activity when grown on wheat bran. Maximum activity of thermostable $\alpha$-amylase was obtained by adding $3\%$ soluble starch. However, soybean oil (1 ml $1^{-1}$) could increase the production of $\alpha$-amylase and cellulase in 'wheat bran. The $\alpha$-amylase was characterized by making a . demonstration of optimum activity at $90^{\circ}C$ and pH 6- 9, with soluble starch as a substrate. The effect of ions on the activity and the stability of this enzyme were investigated. This strain secreted carboxymethyl cellulase (CMCase), cellobiase ($\beta$­glucosidase), and filter paperase (Fpase) during growth on wheat bran. Carboxymethy1cellulase, cellobiase, and Fpase activities had pH optima of 6, 5.5, and 6, respectively. CMCase and cellobiase activities both had an optimum temperature of $50^{\circ}C$, whereas Fpase had an optimum temperature of $45^{\circ}C$.