• Journal of Plant Biology
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• v.34 no.2
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• pp.159-163
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• 1991

The effect of dimethipin, one of the synthesized plant growth regulators, on the gibberellic acid-induced a-amylase activity in the barley de-embryonated seed system was investigated in order to elucidate the possible action mechanism of dimethipin. Dimethipin markedly inhibited the increase of mRNA and protein content, and a-amylase activity induced by gibberellic acid. The inhibitory effects were gradually decreased as the time interval between gibberellic acid treatment and dimethipin addition was made larger. Dimethipin inhibited the increase of mRNA content when added within 18 h from gibberellic acid treatment; however, it inhibited the increase of soluble protein content and a-amylase activity even added after 18 h from the treatment. These results suggest the possibility that dimethipin inhibit both mRNA synthesis and a-amylase protein synthesis.thesis.

• 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.

• 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.

• 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.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.44 no.6
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• pp.791-795
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• 2011

This study examined the inhibitory activity of Ecklonia cava (EC) against ${\alpha}$-amylase to evaluate the availability of EC extract as a functional food agent. To verify the inhibitory activity of EC against porcine pancreatic ${\alpha}$-amylase, potato starch was used as a substrate. This analysis revealed that EC ethanol extract exhibited high ${\alpha}$-amylase inhibitory activity. For potential application within the food industry, the stability of the activity of EC ethanol extract under various heat and pH conditions was examined. The ${\alpha}$-amylase inhibitory activity of EC ethanol extract was not affected by the heat and pH treatment conditions used in this study. These results suggest that EC has the potential for development as a functional food agent.

• Journal of Applied Biological Chemistry
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• v.50 no.2
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• pp.70-73
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• 2007

Antioxidant and anti-diabetic activities of acorn were evaluated by its potential for scavenging stable DPPH free radical, inhibition of lipid peroxidation, reducing power, and inhibiton of ${\alpha}-glucosidase\;and\;{\alpha}-amylase$. The water extract of acorn exhibited strong antioxidant and antidiabetic related activities in the tested model systems. Solvent fractionation of the water extract revealed that the water fraction and the EtOAc fraction had strong antioxidant activity, and inhibitory activity on ${\alpha}-glucosidase\;and\;{\alpha}-amylase$. The water fraction exhibited higher DPPH radical scavenging activity ($EC_{50}=7.19{\mu}g/mL$) than that of ${\alpha}-tocopherol\;(EC_{50}=7.59{\mu}g/mL)$. It is considered that water extract of acorn has the potential for natural antioxidant and anti-diabetic products.

• Journal of Life Science
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• v.18 no.7
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• pp.1005-1010
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• 2008

In this study, we investigated the inhibitory effect of four solvent fractions of Alnus firma on ${\alpha}-amylase$, ${\alpha}-glucosidase$ and aldose reductase activities. The inhibitory test showed that methanol (MeOH) extract and hexane (HX) fraction strongly inhibited pork pancreatin and salivary ${\alpha}-amylase$ activity. The MeOH extract and HX fraction of Alnus firma at the concentration of 4 mg/ml inhibited more than 70% of pancreatin and salivary ${\alpha}-amylase$ activity. The inhibitory effect of fractions has different specificities against ${\alpha}-amylase$ from pancreatin and salivary. In addition, the MeOH extract and butanol (BuOH) fraction showed the highest inhibitory activity on yeast ${\alpha}-glucosidase$ at values of $IC_{50}$ $137.36\;{\mu}g/ml$ and $115.14\;{\mu}g/ml$ respectively. The MeOH extract and BuOH fraction showed the highest inhibitory activity on yeast ${\alpha}-glucosidase$ than commercial agent such as 1-deoxynorjirimycin and acarbose. Inhibition kinetics of solvent fractions showed that ${\alpha}-glucosidase$ has been inhibited noncompetitively by the MeOH, EA and BuOH fraction. The aldose reductase from human muscle cell had been inhibited strongly by the MeOH extract and EA fraction at 57.996% and 83.293% at the concentration of $50\;{\mu}g/ml$, respectively. These findings may contribute to biological significance in that ${\alpha}-amylase$, ${\alpha}-glucosidase$ and aldose reductase inhibitory compounds could be used as a functional food and a drug for the symptomatic treatment of antidiabetic disease in the future.

• Korean Journal of Plant Resources
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• v.27 no.6
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• pp.622-628
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• 2014

The aim of this work is to evaluate the potential of oriental melon (Cucumis melo L. var. makuwa Makino) seeds for the management of type 2 diabetes by controlling glucose absorption. The ${\alpha}$-glucosidase and ${\alpha}$-amylase inhibitory effects of the hexane extracts from oriental melon seeds were investigated. A bioassay-guided fractionation technique was used to elucidate the principal active components. The results show that the hexane extract from oriental melon seeds exhibited high inhibitory activities against ${\alpha}$-glucosidase and ${\alpha}$-amylase. The hexane extract was further fractionated into four sub-fractions. Among them, the sub-fraction F-1 exhibited the most potent anti-diabetic effect. The active components were isolated and identified by gas chromatography/mass spectroscopy (GC-MS). Free fatty acids showed significant hypoglycemic activity (p < 0.001) and fatty acid composition influenced enzyme inhibitory activities. These results suggest that oriental melon seeds could be used to prevent type 2 diabetes.

• Applied Biological Chemistry
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• v.50 no.3
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• pp.204-209
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• 2007

The objective of this research was to evaluate the inhibitory activities of phenolic compounds isolated from Crataegi Fructus on ${\alpha}-amylase$ and ${\alpha}-glucosidase$. The content of total phenolic compounds of water extract from Crataegi Fructus was 22.5 mg/g. The inhibitory activity of the water extract (200 ${\mu}g/ml$) from Crataegi Fructus on ${\alpha}-amylase$ and ${\alpha}-glucosidase$ was determined to be 100% and 82.6%, respectively. Isolation of inhibitory compounds was carried out on Sephadex LH-20 and MCI-gel CHP-20 column chromatography using a gradient elution procedure of increasing MeOH in $H_2O$. The chemical structure of the inhibitory compound against ${\alpha}-amylase$ and ${\alpha}-glucosidase$ was confirmed as chlorogenic acid by spectroscopic analysis of FAB-MS, NMR and IR spectrum.

• Culinary science and hospitality research
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• v.18 no.5
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• pp.233-242
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• 2012

Jehotang is a cold traditional Korean drink made with honey and several ingredients used in traditional Korean medicine. The ingredients include Fructus mume, Fructus amomi, Fructus tsaoko, Santalum album and honey. In this study, Jehotang and its ingredients were determined through the analysis of antioxidant activity, total phenolic content, ${\alpha}$-glucosidase and ${\alpha}$-amylase inhibitory activity. In addition, quality characteristics of Jehotang made by a traditional recipe(Yeonmil) and a modern recipe(double boiling and boiling) were also compared in terms of pH, color and sugar content. Total phenolic content of extract from Fructus ammomi was found to be 120.45 mg, and Yeonmil recipe was discovered 152.66 mg equivalent of gallic acid per g of extract. DPPH free radical scavenging activity were Feuctus amomi(93.13%) and Yeonmil recipe(56.44%). The Fructus amomi extract showed the highest ${\alpha}$-glucosidase inhibitory activity(89.51%) at the concentration of $100{\mu}g/mL$. ${\alpha}$-glucosidase and ${\alpha}$-amylase inhibitory activity of boiled Jehotang were 52.38% and 72.52%, respectively. These results suggest that extract of Fructus amomi has an antioxidant activity and antidiabetic effects. Yeonmil recipe is useful for antioxidant effects more than the others. Also, the double boiling recipe has an excellent antidiabetic effect.