• Journal of Marine Bioscience and Biotechnology
• /
• v.7 no.1
• /
• pp.11-18
• /
• 2015

An extracellular alkaline ${\alpha}$-D-mannosidase produced by a strain named as MA-01 was produced and its preliminary enzyme activity was characterized. Upon determining the 16S rDNA sequence and its homology search, the strain was identified to be one of species of the Bacillus safensis. Localization of enzyme was elucidated that ${\alpha}$-D-mannosidase can be found in culture medium as an extracellular enzyme. In addition, partial enzyme activity of 63% compared with the extracellular enzyme activity was observed in membrane protein. The optimal pH and temperature of the ${\alpha}$-D-mannosidase were pH 7.5 and $37^{\circ}C$, respectively. The $K_m$ and $V_{max}$ values of the ${\alpha}$-D-mannosidase in crude enzyme toward p-nitrophenyl-${\alpha}$-D-mannopyranoside were determined to be $455.6{\mu}M$ and $10.8{\mu}mole/min/mg$ of protein, respectively. To the best of our knowledge, this is the first report described the alkaline ${\alpha}$-D-mannosidase from the family of B. safensis.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.40 no.2
• /
• pp.308-315
• /
• 2011

We investigated ${\alpha}$-amylase, ${\alpha}$-glucosidase and lipase inhibitory activity of extracts collected from wild plants in Gangwon-do. 90 wild plants were collected and their water and ethanol extracts were obtained. Results of measuring ${\alpha}$-amylase inhibitory activity indicated more than 80% of activity inhibition in 10 mg/mL concentration for ethanol extracts of three plants and water extracts of two plants. For ${\alpha}$-glucosidase inhibitory activity, ethanol extracts of thirteen plants and water extracts of three plants showed more than 80% of activity inhibition in 10 mg/mL concentration. In the experiment of inhibiting lipase activity, ethanol extracts of seven plants and water extracts of one plants showed above 80% of activity inhibition in 10 mg/mL concentration. These results suggest that the selected extracts could be potentially used as a resource of bioactive materials for health functional foods.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.44 no.5
• /
• pp.681-686
• /
• 2015

The purpose of this study was to measure total phenolic compounds as a measure of antioxidant activity as well as ${\alpha}$-amylase inhibitory and ${\alpha}$-glucosidase inhibitory activities as a measure of anti-diabetic efficacy in methanol extracts from 23 kinds of medicinal plants. Extracts of three medicinal plant species showing high total polyphenol contents were selected (Euonymus alatus stem, Taxus cuspidata fruit, and Eucommia ulmoides leaf). Extracts of six medicinal plant species showing over 60% DPPH radical scavenging activity were also selected [Eucommia ulmoides barks (80.10%), Lycium chinense roots (64.25%), Euonymus alatus stem (73.59%), Lespedeza cuneata (78.20%), Taxus cuspidata fruits (70.52%), and Tilia taquetii leaf and stem (67.81%)]. Regarding ${\alpha}$-glucosidase and ${\alpha}$-amylase inhibitory activities acarbose showing approximately 80% inhibitory activity was selected as a control group, and six species (Eucommia ulmoides heartwood, Eucommia ulmoides bark, Euonymus alatus stem, Dioscorea batatas, Coix lachryma-jobi, and Phaseolus radiatus) showed greater than 80% ${\alpha}$-glucosidase inhibitory activity. Extracts of nine medicinal plant. species showing over 80% ${\alpha}$-amylase inhibitory activity (Pueraria thunbergiana root, Eucommia ulmoides bark, Eucommia ulmoides leaf, Lycium chinense fruits, Euonymus alatus leaf and stem, Euonymus alatus stem, Sasa borealis whole, Dioscorea batatas leaf and stem, and Tilia taquetii leaf and stem). Based on these results, medicinal plants showing high antioxidant and antidiabetic activities can be used as fundamental products in developing new medicines, as well as functional foods to prevent adult disease.

• Toxicological Research
• /
• v.29 no.4
• /
• pp.257-261
• /
• 2013

${\alpha}$-Curcumene is one of the physiologically active components of Curcuma zedoaria, which is believed to perform anti-tumor activities, the mechanisms of which are poorly understood. In the present study, we investigated the mechanism of the apoptotic effect of ${\alpha}$-curcumene on the growth of human overian cancer, SiHa cells. Upon treatment with ${\alpha}$-curcumene, cell viability of SiHa cells was inhibited > 73% for 48 h incubation. ${\alpha}$-Curcumene treatment showed a characteristic nucleosomal DNA fragmentation pattern and the percentage of sub-diploid cells was increased in a concentration-dependent manner, hallmark features of apoptosis. Mitochondrial cytochrome c activation and an in vitro caspase-3 activity assay demonstrated that the activation of caspases accompanies the apoptotic effect of ${\alpha}$-curcumene, which mediates cell death. These results suggest that the apoptotic effect of ${\alpha}$-curcumene on SiHa cells may converge caspase-3 activation through the release of mitochondrial cytochrome c.

• Korean Journal of Food Science and Technology
• /
• v.29 no.3
• /
• pp.601-608
• /
• 1997

In order to search for the way to utilize rice hull as a renewable resource, the inhibition on ${\alpha}-glucosidase$ and the fractionation of rice hull extract was investigated. An ethanol extract of rice hull from Japonica-type rice seeds exhibited 30% inhibitory activity on rat intestinal brush border ${\alpha}-glucosidase$ (1.4 mU/mL) in vitro at the concentration of 0.8 mg/mL using 6 mM p-nitrophenyl ${\alpha}-D-glucopyranoside$ as a substrate $(IC_{50}\;162\;mg/mL)$. Among the fractions obtained by partitioning the ethanol extract successively with solvents, the ethyl acetate fraction at the concentration of 0.8 mg/mL was found to exhibit the most potent inhibitory activity i.e. 65% inhibition of ${\alpha}-glucosidase\;(IC_{50}\;0.14\;mg/mL)$. Silica gel column chromatography of the ethyl acetate fraction exhibited slightly higher (90%) inhibitory activity, and its subsequent fractionation by Sephadex LH-20 column chromatography did not improve inhibitory activity. Considering the inhibitory activity and yield, the ethyl acetate fraction obtained by the solvent-partitioning process would be a candidate for the hypoglycemic food if it has in vivo effectiveness.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.45 no.2
• /
• pp.108-111
• /
• 2000

Osmoconditioning and hardening effects for the seed germination of normal and naturally aged rice seeds were studied through analyzing the total sugars and $\alpha$-amylase activity. The normal seeds which used to have high germination rate accelerated germination with the osmoconditioning at the suboptimal temperature of 17$^{\circ}C$. On the other hand, the aged seeds did not affect germination rate at $25^{\circ}C$, while increased germination rate and accelerated germination a little at 17$^{\circ}C$, Hardening of aged seeds increased germination rate by 10-15% compared with control seeds at both 17 and $25^{\circ}C$ and accelerated germination. Total sugar content and $\alpha$-amylase activity of normal seeds were higher than did aged seeds. The aged seeds with treatment of osmoconditioning and hardening increased total sugar content and $\alpha$--amylase activity, but hardening was more effective than osmoconditioning. The $\alpha$--amylase activity was positively correlated with the total sugar content and germination rate.

• The Korean Journal of Physiology
• /
• v.16 no.2
• /
• pp.111-117
• /
• 1982

Slices of rat corpora lutea(CL) incubated with. prostaglandin $F_{{2{\alpha}}}(PGF_{2{\alpha}})$ in Krebs-Hensenleit (K-H) Ringer solution showed a decrease in $Na^+-K^+$-ATPase activity after 60 min of incubation. However, $PGF_{2{\alpha}}$ in vitro did not alter $Na^+-K^+$-ATPase activity of isolated luteal membrane fractions. Following $PGF_{2{\alpha}}$ induced in vivo luteal regression, reduction of Vmax an elevation of the activation energy above transition temperature of the lipid phase of the membrane occurred without changes of Km, optimum pH and transition temperature. These results suggest that reduction of $Na^+-K^+$-ATPase activity after $PGF_{2{\alpha}}$ treatment may be due to the reduction of the number of enzyme molecules or to masking of the active site of the enzyme without any change in enzyme characteristics. In addition, a change in membrane bound enzyme activity may be an early step in $PGF_{2{\alpha}}$ induced luleolysis.

• Korean Journal of Pharmacognosy
• /
• v.47 no.1
• /
• pp.24-28
• /
• 2016

This study was to evaluate the effect of ginseng (Panax ginseng) seed oil on the ${\alpha}$-glucosidase and ${\alpha}$-amylase. Each ginseng seed oils (HE, SE, EE) exhibited a significant inhibitory effect (p<0.001) at all concentrations (10 and 20 mg/ml) on ${\alpha}$-glucosidase activity. HE is the highest inhibitory activity (86.92%) at a concentration of 20 mg/ml, SE and EE showed an inhibitory effect of 77.13% and 65.83%, respectively. And also, Each ginseng seed oils (HE, SE, EE) exhibited a significant inhibitory effect (p<0.001) at all concentrations (1 and 2 mg/ml) on ${\alpha}$-amylase activity. HE is the highest inhibitory activity (89.68%) at a concentration of 2 mg/ml, SE and EE showed an inhibitory effect of 76.99% and 65.70%, respectively.

• Journal of Microbiology and Biotechnology
• /
• v.14 no.6
• /
• pp.1196-1199
• /
• 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 $45^{\circ}C$.

• Korean Journal of Microbiology
• /
• v.48 no.4
• /
• pp.305-308
• /
• 2012

In this study, we evaluated antifungal and antioxidant activities of condensed liquid of volatile organic compounds generated during the drying process of Chamaecyparis obtuse. Condensed liquid of volatile organic compounds were extracted with hexane and ethyl acetate, respectively. The extracts were used for antifungal activity at range from 100 to 500 mg/L Antifungal activity of extracts increased as the extracts concentration increased, the activity against tested dermatophytes was high at 500 mg/L. Among extract solvents, antifungal activity was higher at hexane extract than the ethyl acetate. Especially, the antifungal activity against Trichophyton rubrum was higher than other tested dermatophytes. Antioxidant activity was 90% above 25 mg/L regardless of the extractive solvents, while the hexane extract showed high antioxidant activity below 25 mg/L. Major compounds of hexane extract were torreyol, alpha-cadinol, and tau-cadinol. However, major compounds of ethyl acetate extract were alpha-amorphene, alpha-cadinol, and gamma-cadinene.