• The Korean Journal of Food And Nutrition
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• v.6 no.4
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• pp.307-313
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• 1993

Bacillus cereus $\beta$-amylase was purified by Sephadex G-100 gel filtration, CM Sephadex C-50 ion exchange chromatography and CM Sephadex C-50 ion exchange rechromatography The purified enzyme showed 871 unit/mg of specific activity. The purified enzyme was identified as homogenious by disc PAGE, SDS-PAGE and analysis of reaction product. The purified enzyme showed optimum pH 7.0. optimum temperature 5$0^{\circ}C$, and was stable at 0~5$0^{\circ}C$ and at pH range of 6~10.

• 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%.

• Korean Journal of Food Science and Technology
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• v.26 no.4
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• pp.459-463
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• 1994

To improve the quality of rice-cake(Cholpyon), raw starch saccharifying (${\beta}-amylase$ from Bacillus polymyxa No. 26 was used in process of raw rice-cake production. 30g of raw rice flour was incubated with $0{\sim}1,200$ RS units of the enzyme for 5 hr at $45^{\circ}C$, and then steamed and stored for 40 hr at $4^{\circ}C$. In instrumental analysis, control group, which was incubated without addition of (${\beta}-amylase$, was completely hardened after incubation for $12{\sim}24$ hr at $4^{\circ}C$. In contrast, enzyme-treated group was not retrograded, and showed a great differences in hardness, cohesiveness and chewiness. On the other hand, in sensory analysis, the effect of the enzyme treatment was higher values of hardness, moistness, and sweetness than these of control group. Therefore, these results clearly suggested that ${\beta}-amylase$ was fully active to degrade raw rice starch in process of rice-cake production, resulting in improvement of starch retrogradation, good digestibility, and taste.

• Korean Journal of Food Science and Technology
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• v.24 no.6
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• pp.568-573
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• 1992

Molecular structural properties of Japonica and Tongil type waxy rice starches were compared. The general properties including water-binding capacity, swelling power at $80^{\circ}C$, intrinsic viscosity, leach loss at $98^{\circ}C$ and ${\beta}-amylolysis$ limit were similar but the chain length was slightly different between the two starches. Similar elution profiles on Sephadex G-50 were obtained when the starches were treated with ${\beta}-amylase$. The pullulanase treated starches however showed different elution patterns each other. The ${\beta}-amylolysis$ of acid-treated (2 days) starches linearly increased as hydrolysis time prolonged. When the acid-treated starches were hydrolyzed with ${\beta}-amylase$ or pullulanase, the elution profiles on Sepharose CL-2B were considerably different from those of native starches.

• Korean Journal of Food Science and Technology
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• v.5 no.4
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• pp.224-230
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• 1973

The culture used wheat bran as media for four kind of mold strains such as Aspergillus oryzae, Aspergillus kawachii, Aspergillus usamii and Rhizopus javanicus to examine which strain could higher the activity of amylase most which is used for alcohol fermentation. It also provided three different kind of wheat bran media containing starch of 47%, 51% and 55% respectively for each strain. For each media it also added three different kind of nitrogen sources; ammonium sulfate, casein, and ammonium sulfate and casein equally mixed. Each nitrogen source added was subordinately differentiated into three different percentages, 2%, 4% and 6% respectively, except the 2% for the ammonium sulfate. The results obtained were summarized as follows (1) The activity of ${\alpha}-amylase$ was highest in the media of starch value 47% of wheat bran with 6% of casein added. (2) The activity of ${\beta}-amylase$ was highest in the media of starch value 51% of wheat bran with 2% of the equal mixture of ammonium sulfate and casein added. (3) The activities of both ${\alpha}-amylase$ and ${\beta}-amylase$ of Aspergillus usamii were highest in the media of starch value 47% wheat bran with no addition of nitrogen source. (4) Of the four strains examined, the activities of ${\alpha}-amylase$ and ${\beta}-amylase$ cultured in Rhizopus javanicus were both relatively higher. (5) The activities of ${\alpha}-amylase$ and ${\beta}-amylase$ of the strains examined became lower as the percentage of starch contents increased except in Rhizopus javanicus.

• The Korean Journal of Food And Nutrition
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• v.9 no.3
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• pp.247-252
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• 1996

$\beta$-Amylase was purified from sweet potato by acetone fractlonatlon, Sephadex A-50 ion exchange chromatography and Sepgadex G-200 gel chromatographyl The higher enzyme concentration was, the higher heat stability of enzyme became. After 1 hour 30 minute. At 6$0^{\circ}C$ in pH 5, enzyme under concentration of 30$\mu$l/ml lost its activity completely and over the concentration of 100$\mu$g/ml remained 25% of activity. The enzyme was stabilized at range of pH 4~10 and pH stability was increased by glycerol. Five moles of NaCl inhibited completely of the enzyme activity. SDS of 0.05% inhibited the enzyme completely after 12 hours at 37$^{\circ}C$ in pH5. One mole guanidine-HCl and 8M urea inhibited the entire enzyme after 13 hours at 37$^{\circ}C$ in pH 5.

• Korean Journal of Food Science and Technology
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• v.37 no.2
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• pp.189-193
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• 2005

Effect of enzyme treatment on physicochemical characteristics of small tea bean percolate were estimated. Three types of small red bean percolate were prepared by heat treatment for 30 min at $95^{\circ}C$ (1st), 30 min at $95^{\circ}C$ (2nd), and 40 min at $120^{\circ}C$ (3rd). They were then treated with 0.5% ${\alpha}-amylase$ (v/v) for 4 hr at $108^{\circ}C$ (${\alpha}-amylase$ treatment), then with 0.5% ${\beta}-amylase$ (v/v) for 4 hr at $60^{\circ}C$ (${\alpha}-$ and ${\beta}-amylase$ treatment). Crude saponin contents of 1st-3rd percolates were 0.82, 1.44, and 1.52 mg/g, respectively. ${\circ}Brix$ of small red bean percolates treated with enzymes increased to $0.8-1.2\;{\circ}Brix$ with 2nd and 3rd percolates showing no significant difference between ${\alpha}-amylase$ and ${\alpha}-$ and ${\beta}-amylase$ treatments. pH of 3rd percolate treated with ${\alpha}-$ and ${\beta}-amylase$ decreased from initial 6.2 to 4.7. Hunter L value of small red bean percolate treated with ${\alpha}-$ and ${\beta}-$ decreased, whereas a and b values increased. Small red bean beverage made with 3rd percolate showed high score in flavor, taste, and overall acceptability. Results suggest small red bean percolate treated with enzymes could be used for preparation of small red bean beverage.

• The Korean Journal of Physiology and Pharmacology
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• v.7 no.4
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• pp.217-221
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• 2003

To clarify the roles of gonadal steroids on pancreatic exocrine secretion, effects of progesterone and estradiol-$17{\beta}$ on spontaneous and secretagogue-induced exocrine response of isolated perfused rat pancreas were investigated. Intra-arterial infusion of progesterone resulted in significant increase of the spontaneous pancreatic fluid and amylase secretion dose-dependently. However, estradiol-$17{\beta}$ did not exert any influence on spontaneous pancreatic exocrine secretion. Exogenous secretin, cholecystokinin (CCK), and acetylcholine markedly stimulated pancreatic fluid and amylase secretion. Progesterone initially enhanced secretin-induced amylase secretion, but this stimulatory response declined thereafter to basal value. Moreover, secretin-induced fluid secretion was not affected by infusion of progesterone. Therefore, initial increase of secretion-induced amylase secretion by progesterone seems to be a non-specific action by washout effect of secretin. Estradiol-$17{\beta}$ failed to change the secretin-induced fluid and amylase secretion. Both progesterone and estradiol-$17{\beta}$ did not exert any influence on CCK-induced fluid and amylase secretion. Acetylcholine-induced exocrine secretion of isolated perfused pancreas also was not affected by intra-arterial infusion of progesterone or estradiol-$17{\beta}$. It is concluded from the above results that progesterone could enhance the spontaneous pancreatic fluid and amylase secretion of isolated perfused rat pancreas through non-genomic shortterm action, and that these effects could be masked by more potent stimulants such as secretin, CCK, and acetylcholine.

• Microbiology and Biotechnology Letters
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• v.6 no.1
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• pp.9-16
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• 1978

Effects of the addition of Ginseng extract and it's incubation time on enzyme activity (${\alpha}$-amylase, ${\beta}$-amylase, protease) of Aspergillus app. was investigated. 1. ${\alpha}$-Amylase activity of Asp. oryzae was higher for 48 hours than control, however, the same after 48 hours. ${\beta}$-Amylase activity was stimulated at the concentration of 0.1 to 1.0％, and decreased at the concentration of 3.0 to 5.0％. The acid protease activity was higher than control for 72 hours and in the medium of 120 hours was decreased significantly. The alkaline protease activity was lower than control. However, alkaline protease activity was higher than acid protease activity. 2. ${\alpha}$-Amylase of Asp. niger was increased in proportion to increasing of the extract concentration. ${\beta}$-Amylase was increased at the concentration from 0.5 to 3.0％ and it's activity was depressed in proportion to increasing of the extract concentration for 48 hours and on the contrary it was improved in proportion to increasing of the extract concentration for 72 hours except for 5.0％ concentration with marked decreasing. Alkaline protease activity was increased at lower concentration (0.1∼0.5％) for 24 to 48 hours and it was depressed at higher concentration (1.0 to 5.0), however after 48 hours incubated, it's activity was decreased in preparation to increasing of the extract concentration.

• Journal of Microbiology and Biotechnology
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• v.18 no.4
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• pp.695-703
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• 2008

A locally isolated thermophile, Geobacillus sp. SAB-40, producing thermostable extracellular amylase constitutively and an induced intracellular ${\beta}$-galactosidase was characterized and identified based on 16S rRNA sequencing. A phylogenetic analysis then revealed its closeness to Geobacillus stearothermophilus. To evaluate the effect of the culture conditions on the coproduction of both enzymes by G stearothermophilus SAB-40, a Plackett-Burman fractional factorial design was applied to determine the impact of twenty variables. Among the tested variables, $CaCI_2$, the incubation time, $MgSO_4{\cdot}7H_2O$, and tryptone were found to be the most significant for encouraging amylase production. Lactose was found to promote ${\beta}$-galactosidase production, whereas starch had a significantly negative effect on lactase production. Based on a statistical analysis, a preoptimized medium attained the maximum production of amylase and ${\beta}$-galactosidase at 23.29 U/ml/ min and 12,958 U/mg biomass, respectively, which was 3-and 2-fold higher than the yield of amylase and lactase obtained with the basal medium, respectively.