• YAKHAK HOEJI
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• v.33 no.3
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• pp.175-182
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• 1989

To find ${\alpha}-amylase$ inhibitors produced by microorganisms from soil, a strain which had a strong inhibitory activity against bacterial ${\alpha}-amylase$ was isolated from the soil sample collected in Korea. The morphological and physiological characteristics of this strain on several media and its utilization of carbon sources showed that it was one of Streptomyces species according to the International Streptomyces Project method. The amylase inhibitor of this strain was purified by active carbon adsorption, silicagel column chromatography, SP-Sephadex C-25 column chromatography, adsorption on Amberlite XAD-2. The inhibitor was oligosaccharide which was composed of glucose. The inhibitor had inhibitory activity against other amylase such as salivary ${\alpha}-amylase$, pancreatic ${\alpha}-amylase$, fungal ${\alpha}-amylase$ and gluco-amylase.

• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.4
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• pp.556-562
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• 1995

The $\alpha$-amylase inhibitor from naked barley was purified by DEAE-cellulose, Concanavalin-A sepharose and superose 6 column chromatography, and confirmed by capillary electrophoresis. The purified $\alpha$-amylase inhibitor showed a single band of 29KD in molecular weight when estimated by the SDS-PAGE. Its purity was increased by 12-fold as compared to its crude extract, and its specific activity was found to be 336.7units/mg. The major amino acids of the $\alpha$-amylase inhibitor from naked barley was appeared to be glutamic acid, asparitic acid and arginine. The inhibitor from naked barley was glycoproteins and carbohydrate content of inhibitor was 1.0%.

• Archives of Pharmacal Research
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• v.8 no.2
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• pp.67-75
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• 1985

To find emylase inhibitors produced by microorganisms from soil, a strain which had a strong inhibitory activity against bacteria .alpha.-amylase was isolated from the soil smaple collected in Seoul. The morphological and physiological characteristics of this strain on several media and its utilization of carbon sources showed that it was one of Streptomyces specties according to the international Streptomyces Project method. The amylase inhibitor of this strain was purified by means of acetone precipitation, adsorption on Amberlite XAD-2, and column chromatography on Amberlite CG-50 and SP-Sephadex C-25. The inhibitor was stable at the pH range of 1-10 and at 100.deg.C for half an hour, and had inhibitory activities against other amylases such as salivary .alpha.-amylase, pancreatic .alpha.-amylase, fungal .alpha.-amylase and glucoamylase. The kinetic studies of the inhibitor showed that its inhibitory effect on starch hydrolysis by .alpha.-amylase was non-competitive.

• Korean Journal of Food Science and Technology
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• v.27 no.5
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• pp.762-767
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• 1995

The ${\alpha}-Amylase$ inhibitor from black bean(Phaseolus vulgaris) was purified to homogeneity using 70% saturated ammonium sulfate, DEAF-cellulose, Concanavalin-A sepharose chromatography and gel filtration with Superose 6. The purified α-amylase inhibitor showed a single band of 25 KD in molecular weight on the SDS-PAGE. The specific activity of the inhibitor was 544.0 units/mg and the purity was enhanced about 18-fold. The amino acids of ${\alpha}-Amylase$ inhibitor from black bean was mainly glutamic acid, aspartic acid and lysine. The inhibitor was glycoproteins and its carbohydrate contents was 3.2%.

• YAKHAK HOEJI
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• v.36 no.4
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• pp.390-396
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• 1992

Streptomyces minoensis DMCJ-144 isolated from soil produces the ${\alpha}-amylase$ inhibitor. Optimum culture conditions for ${\alpha}-amylase$ inhibitor production of the strain were determined in this experiment. The optimum composition of the culture medium was studied by supplementing various carbon sources, nitrogen sources, vitamins, and metal salts to the basal medium containing 1% glucose, 0.1% asparagine, 0.005% $MgSO_4{\cdot}7H_2O$, 0.005% $K_2HPO_4$, 0.005% NaCl. Other culture conditions such as the culture temperature, initial pH of the medium, aeration, and culture time were also investigated. When the strain was cultured in a 100 ml flask containing 20 ml of 2% glucose, 0.5% beef extract, 0.0002% riboflavin, 0.0002% thiamine HCI, 0.01% $ZnCl_2$, 0.005% $MgSO_4{\cdot}7H_2O$, 0.005% $CuSO_4{\cdot}5H_2O$, 0.005% NaCl, pH 7.2, 180 rpm at $30^{\circ}C$, the maximum production of the ${\alpha}-amylase$ inhibitor was observed after 5 days of the cultivation.

• Microbiology and Biotechnology Letters
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• v.18 no.4
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• pp.338-343
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• 1990

MB4-03, an $\alpha$-amylase inhibitor was isolated from the culture broth of Streptomyces sp. DMCJ-49 and purified through ion-exchange chromatography, adsorption, and gel filtration. The results of various instrumental analyses showed that the inhibitor was one of oligosaccharides that had glucoses as its major component and that its molecular weight was about 2000. And one methyl group which seemed to be related with the inhibitory activity of this compound was identified. From the CMR spectrum, it was elucidated that this compound was composed of $\alpha$ -D-glucopyranoses which were linked together by $\alpha$ (I -, 4) bond configuration. As the inhibitory effect of this compound was reduced after incubation with $\beta$-amylase, the maltose units was seemed to exist at non-reducing terminal side of it.

• Biomolecules & Therapeutics
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• v.1 no.1
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• pp.26-30
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• 1993

Strain of treptomyces minoensis DMCJ-144 was tried to be improved so that it produces much more the $\alpha$-amylase inhibitor. Streptomyces minoensis DMCJ-144 was treated with 1 mg/mι (pH 9.0) of N-methyl-N'-nitro-N-nitrosoguanidine at $30^{\circ}C$ for 60 min and irradiated with UV light distanced 30 cm for 20 min. After mutagenesis, surviving colonies were cultured on the CM contaning acriflavine ($10{\mu}g/ml$) three times in order to enhance the mutability. And then through multi-level screening, colonies that ${\alpha}$-amylase inhibitor productibility. was Improved were selected by modified-blue value method. After third acriflavine treatment, $\alpha$-amylase inhibitory activities of selected colonies were found to be much better as compared with that of parent strain. One mutant strain showed 5.4 time inhibitory activity than the parent strain.

• Preventive Nutrition and Food Science
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• v.19 no.1
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• pp.5-9
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• 2014

This study was designed to investigate the inhibitory effects of Polyopes lancifolia extract (PLE) on ${\alpha}$-glucosidase activity, ${\alpha}$-amylase activitiy, and postprandial hyperglycemia in streptozotocin (STZ)-induced diabetic mice. The results of this study revealed a marked inhibitory effect of PLE on ${\alpha}$-glucosidase and ${\alpha}$-amylase activities. The $IC_{50}s$ of PLE against ${\alpha}$-glucosidase and ${\alpha}$-amylase were 0.20 mg/mL and 0.35 mg/mL, respectively. PLE was a more effective inhibitor of ${\alpha}$-glucosidase and ${\alpha}$-amylase activities than acarbose, the positive control. The postprandial blood glucose levels of STZ-induced diabetic mice were significantly lower in the PLE treated group than in the control group. Moreover, PLE administration was associated with a decreased area under the curve for the glucose response in diabetic mice. These results indicate that PLE may be a potent inhibitor of ${\alpha}$-glucosidase and ${\alpha}$-amylase activities and may suppress postprandial hyperglycemia.

• YAKHAK HOEJI
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• v.35 no.1
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• pp.30-37
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• 1991

Streptomyces actuosus DMCJ-49 and Streptomyces minoensis DMCJ-144 produce the .alpha.-amylase inhibitor. Inerspecific protoplast fusion technique was used to increase the productivity of .alpha.-amylase inhibitor. Four auxotrophic mutants were obtained respectively from two strains by N-methyl-N'-nitor-N-nitrosoguanidine(3mg/ml) treatment. The optimum conditions for the protoplast formation of Streptomyces actuosus DMCJ-49 ade was as follows; 1.2% w/v of glycine, 3mg/ml of lysozyme, and 30 min of lysozyme treatment followed by 36 hr. incubation in the protop-last formation medium. In case of DMCJ-144-his those were 1.2%w/v, 3 mg/ml, 30 minutes and 60 hours, respectively. Regeneration was accomplished with hypertonic soft agar medium that contained 0.4M sucrose, 20mM CaCl$_2$, 50 mM MgCl$_2$ and low levels of phosphate. Fusion of protoplasts carrying different auxotrophic markers was achieved by treatment with polyethylene glycol. The optimum concentration of polyethylene glycol 1450 for the production of recombinants was 40%w/v. When the protoplasts was treated with 40% polyethylene glycol for 30 minutes, the frequency of recombinants was 6.5$\times$$10^{-3}$ and the $\alpha$-amylase inhibition activity of $ade^-his^-$ No. 4, which is the fusant with the most improved activity increased from 33 to 125 I.U./ml.

• Korean Journal of Food Science and Technology
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• v.20 no.5
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• pp.644-649
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• 1988

The inhibitory activities against bacterial ${\alpha}-amylase$of oriental drugs from animals, plant and mineral origin were investigated. In final screening test, it was found that Areca catechu L., Cinnamomum cassia Pres 1. and Ephedra sinica Stapf had stronger inhibitory activities against ${\alpha}-amylase$ than other oriental drugs used in this experiment.