• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.11
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• pp.1401-1407
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• 2008

1-Deoxynojirimycin (DNJ) is a strong $\alpha$-glucosidase inhibitor which inhibits hyperglycemia in animals. To select the Bacillus strains highly producing DNJ, 4,000 strains were isolated from soil and grain samples. By the inhibitory activity against $\alpha$-glucosidase, nine Bacillus strains were selected and then identified by 16S rDNA sequencing. B. subtilis S10 was finally selected as the best strain for the production of DNJ. Various carbon sources and nitrogen sources in culture medium were evaluated for the highest production of DNJ. As the results, the optimized concentration of carbon source and nitrogen source was 1.0% galactose and 1.6% polypeptone and the concentration of DNJ produced was 0.75 g/L. The effect of culture supernatant of B. subtilis S10 on lowering blood glucose level was investigated in streptozotocin (STZ)-induced diabetic mice model. Mice were randomly assigned to control group (saline) and three test groups such as acarbose group, silkworm powder group and B. subtilis S10 group. After eight-week oral feeding, blood glucose levels of the B. subtilis S10 and silkworm powder groups were respectively $209.1{\pm}19.6\;mg/dL$ (59.1%) and $208.6{\pm}39.8\;mg/dL$ (59.0%) lower than $510{\pm}10\;mg/dL$ of the control group. These results indicated that the culture supernatant of B. subtilis S10 was able to reduce the blood glucose level in STZ-induced diabetic mice.

• Journal of Microbiology and Biotechnology
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• v.33 no.6
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• pp.797-805
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• 2023

Species belonging to the Vernonia (Asteraceae), the largest genus in the tribe Vernonieae (consisting of about 1,000 species), are widely used in food and medicine. These plants are rich sources of bioactive sesquiterpene lactones and steroid saponins, likely including many as yet undiscovered chemical components. A phytochemical investigation resulted in the separation of three new stigmastane-type steroidal saponins (1 - 3), designated as vernogratiosides A-C, from whole plants of V. gratiosa. Their structures were elucidated based on infrared spectroscopy (IR), one-dimensional (1D) and two-dimensional nuclear magnetic resonance (2D NMR), high-resolution electrospray ionization mass spectrometry (HR-ESI-MS), and electronic circular dichroism analyses (ECD), as well as chemical reactivity. Molecular docking analysis of representative saponins with α-glucosidase inhibitory activity was performed. Additionally, the intended substances were tested for their ability to inhibit α-glucosidase activity in a laboratory setting. The results suggested that stigmastane-type steroidal saponins from V. gratiosa are promising candidate antidiabetic agents.

• 한국생물공학회:학술대회논문집
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• 2005.04a
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• pp.546-552
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• 2005

The purpose of this study was to determine the effect of rat intestinal ${\alpha}-glucosidase$ inhibitor ; methanol(80%), ethanol(80%) and $dH_2O$ extract of Schizandra chinensis in Korea(KS : Schizandra chinensis in Korea) and China(CS : Schizandra chinensis in China). When the final concentration was 1 $mg/m{\ell}$ for each sample(KS and CS), MeOH extract of KS($IC_{50}$ 1.62 mg/ml) showed 46.8%, EtOH extract of KS($IC_{50}$ 1.48 mg/ml) showed 47.4%, $dH_2O$ extract of KS($IC_{50}$ 1.72 mg/ml) showed 46.3% and MeOH extract of CS($IC_{50}$ 8.35 mg/ml) showed 13.3%, EtOH extract of CS($IC_{50}$ 8.05 mg/ml) showed 16%, $dH_2O$ extract of CS($IC_{50}$ 8.37 mg/ml) showed 11.54% of inhibiter for p-nitrophenyl ${\alpha}$, D-glucopyranoside ${\alpha}-glcosidase$ activity, respectively, And the contents of total phenol, flavonoid of Schizandra chinensis were measured. When the final concentration was 1 $mg/m{\ell}$ for each sample(KS and CS), total phenol and flavonoid in KS were higher than CS, respectively.

• Biomedical Science Letters
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• v.11 no.4
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• pp.517-523
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• 2005

The purpose of this study was to determine the effect of rat intestinal a-glucosidase inhibitor; methanol $(80\%)$, ethanol $(80\%)$ and water extract of Schizandra chinensis in Korea (KS: Schizandra chinensis in Korea) and China (CS: Schizandra chinensis in China). When the final concentration was 1 mg/ml for each sample (KS and CS), methanol extract of KS ($IC_{50}$ 1.62 mg/ml) showed $46.8\%$, ethanol extract of KS ($IC_{50}$ 1.48 mg/ml) showed $47.4\%$, water extract of KS ($IC_{50}$ 1.72 mg/ml) showed $46.3\%$ and methanol extract of CS ($IC_{50}$ 8.35 mg/ml) showed $13.3\%$, ethanol extract of CS ($IC_{50}$ 8.05 mg/lml) showed $16\%$, water extract of CS ($IC_{50}$ 8.37 mg/ml) showed $11.54\%$ of inhibitor for p-nitrophenyl $\alpha-D-glucopyranoside$ (pNPG) $\alpha-glcosidase$ activity, respectively. And the contents of total phenol, flavonoid of Schizandra chinensis were measured. When the final concentration was 1mg/ml for each sample (KS and CS), total phenol and flavonoid in KS were higher than CS, respectively. The order superoxide dismutase (SOD) activity $IC_{50}$ values of each solvent extracts of KS were: 2.006 mg/ml methanol extract, 2.304 mg/ml ethanol extract and 2.5 mg/ml water extract, which were higher than that of each solvent extracts CS as: 2.881 mg/ml methanol extract, 3.085 mg/ml ethanol extract and 3.190 mg/ml water extract.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.4
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• pp.452-458
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• 2008

The effect of fermented soybean culture of Bacillus subtilis MORI mixed with mulberry leaves on the lowering the levels of blood glucose and cholesterol was examined using neonatal streptozotocin-induced diabetic (n-STZ) rats. B. subtilis MORI produces 1-deoxynojirimycin (DNJ), an $\alpha$-glucosidase inhibitor. The content of DNJ of soybean fermented culture mixed with mulberry was higher (4.1$\pm$0.0 mg/g dry base) than that (1.5$\pm$0.0 mg/g) of mulberry. The concentration of 50% inhibition (IC50) against rat intestinal $\alpha$-glucosidase of soybean fermented culture mixed with mulberry was $5.6{\pm}0.1{\mu}g$/mL and that of mulberry was $17.0{\pm}0.5{\mu}g$/mL. Experimental groups of diabetic rats were randomly assigned to normal control group (NC group), diabetic control group (DC group) and three diabetic groups fed with DNJ food product. One of the three diabetic groups was M group (60 mg DNJ food product/kg) (DNJ food product containing 30% mulberry) and the other two were MM-60 group (60 mg/kg) and MM-120 group (120 mg/kg) (DNJ-fortified food product containing 30% fermented soybean culture mixed with mulberry leaves). The glucose in serum was significantly decreased in the MM-60 and MM-120 groups fed with DNJ-fortified food product for 4 weeks, compared with DC group. Total cholesterol and triglyceride in serum were also lower in MM-60 and MM-120 groups than the DC group. These results support that the fermented soybean culture of B. subtilis MORI mixed with mulberry leaves improved the metabolism of blood glucose and lipid in the n-STZ rat model.

• KSBB Journal
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• v.26 no.6
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• pp.517-522
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• 2011

In our previous study, we isolated and characterized a 1-deoxynojirimycin (DNJ)-producing bacterium, Bacillus subtilis MORI, from chungkookjang, a Korean traditional food. B. subtilis MORI was subjected to ${\gamma}$-irradiation and the resulting bacteria were screened for increased DNJ production. A mutant was identified that produced 7.6 times more DNJ and named B. subtilis MORI 3K-85. In this study, the protein profiles of both strains were compared by one-dimensional and two-dimensional gel electrophoresis (1-DE and 2-DE, respectively) under both native and denaturing conditions. The 1-DE native-PAGE and 1-DE SDS-PAGE analyses identified 5 and 7 bands, respectively, that were found at higher concentrations in B. subtilis MORI 3K-85 than in B. subtilis MORI. Similarly, 2-DE analyses identified 20 protein spots which were found at higher concentrations in B. subtilis MORI 3K-85. The peptide mass profiles of these 20 proteins were analyzed by MALDI-TOF and compared with peptide sequences of B. subtilis and B. amyloliquefaciens in the MASCOT database. This screening suggested that three dehydrogenases, an aldolase, a synthetase, an isomerase, a reductase, and a peroxidase are elevated in B. subtilis MORI 3K-85. Based on this data, one or more of the elevated 8 enzymes might be related to the DNJ biosynthetic pathway.