• Microbiology and Biotechnology Letters
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• v.34 no.4
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• pp.368-372
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• 2006

Quercetin is a flavonoid molecule that is known to tie in various sources of natural products such as vegetables and fruits. It has been proven that quercetin plays a crucial role in the prevention of colon cancer as well as homeostasis as radical scavenger in human body. It is also well-known that glycosidases, including $\alpha$-glucosidase, are involved in a variety of degenerative metabolic disorders. In the course of screening useful $\alpha$-glucosidase inhibitors, we screened out quercetin as a $\alpha$-glucosidase inhibitor from chemical libraries. Quercetin was shown to be a reversible, slow-binding, and noncompetitive inhibitor of yeast a-glucosidase with a K$_i$ value of $6.3\times10^{-8}$ M when it was included with an enzyme mixture. Together, these results show that quercetin has potential in treating disorders including diabetes, although the further mechanistic study is needed.

• Journal of Life Science
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• v.25 no.6
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• pp.638-645
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• 2015

This study analyzed the physiological quality of Mesembryanthemum crystallinum (ice plant) extract. M. crystallinum is a succulent plant found in Africa, southern Europe, North America, South America, and Australia. It has known antidiabetic, antioxidant, and activation of lipid metabolism effects. Extracts from M. crystallinum were prepared with methanol (MCM), ethanol (MCE), hot water (MCHW), and methanol after hot water (MCHM) extractions. The yields of MCM, MCE, MCHW, and MCHM were 0.37, 0.33, 0.50, and 0.07%, respectively. To determine the biological activities of the extracts, mushroom tyrosinase, pancreatic lipase, 1,1-diphenyl-2-picryl hydrazyl (DPPH) radical scavenging, nitric oxide (NO) production, and α-glucosidase assays were conducted. The DPPH radical scavenging activity of the MCHW extract was 62.9% at a concentration of 400 μg/ml, which was the highest of all the extracts. The MCM extract showed the highest inhibition activity of α-glucosidase and NO production (56.6 and 57.2%, respectively). The pancreatic lipase inhibition of the MCE extract was similar to that of the MCM extract, with significant inhibition of 90%. The mushroom tyrosinase inhibition of all the extracts was very low (approximately 30%). These results suggest that extracts from M. crystallinum have antioxidant, anti-inflammatory, antiobesity, and antidiabetic activities. Thus, it may have potential as a functional food product and therapeutic potential as an antidiabetic or antiobesity agent.

• Journal of the Korean Applied Science and Technology
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• v.35 no.4
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• pp.1250-1259
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• 2018

In this study, Momordica charantia (MC) fermented with Leuconostoc mesenteroides (MC-LM) were assessed for the antioxidant and the antidiabetic activities. Antioxidant activities of MC and MC-LM were evaluated using 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid)(ABTS) radical. Although MC-treated groups showed little activity, 47% of activity was observed at $500{\mu}g/mL$ concentration for MC-LM and increased significantly(p<0.05) as MC-LM concentration increased. MC-LM more effectively inhibited the oxidative damage of DNA by peroxyl radical than MC and the inhibition of the strand breakage increased significantly as MC-LM concentration increased(p<0.05). Measuring the inhibition of ${\alpha}-glucosidase$ activity, which is closely related to the regulation of blood sugar, resulted in MC reduced the activity of ${\alpha}-glucosidase$ by 30% at 8 mg/mL and MC-LM at the same concentration by 60%. In addition, the effect of MC-LM on the cell viability of alloxan-treated RIN-m5F resulted in a significant increase in cell survival(p<0.05) in the group treated with MC-LM and a 20% increase in the concentration of $1000{\mu}g/mL$. As a result of insulin secretion by alloxan-treated RIN-m5F cell, the level of insulin secretion tended to increase in all group treated with MC-LM. At the concentration of $1000{\mu}g/mL$, the insulin secretion was increased by 15% in MC-LM group than in MC group. In conclusion, the results of this study suggest that fermented bitter gourd has antioxidant and antidiabetic effects.

• Korean Journal of Agricultural Science
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• v.3 no.2
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• pp.225-234
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• 1976

To elucidate ${\beta}$-glucosidase formation on various carbon scurces by cellulolytic bact-eia, Cellulomonas sp. CS1-1, the strain was grown on Nutrient Yeast Broth, carboxymethyl cellulose, avicel and cellobiose using a Ouickfit FVIL fermentor operated in batch, and the growth characteristics on those substrates and ${\beta}$-glucosidase distribution of extra and intracellular enzyme components were studied. The results were: 1) ${\beta}$-glucosidase was always intracellular, and was formed under all growth conditions tested, ii) but levels of relative activities were higher when the culture was grown on cellobiose and on avicel, iii) the relative activities were always maximum during the growth phase of the organism irrespective of the substrate used.

• Journal of Life Science
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• v.27 no.2
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• pp.172-179
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• 2017

The fermentation of Panax ginseng can yield many compounds from ginsenosides that have a wide variety of biological functions. Lactic acid bacteria (LAB) strains are capable of converting ginsenosides. The purposes of this study were to: (1) characterize Enterococcus faecium SA5, an isolated LAB from Mongolian mare milk, (2) identify the existence of extracellular ${\beta}$-glucosidase activity in the milk, and (3) ascertain if the ${\beta}$-glucosidase has the capacity of converting ginsenoside in Korean ginseng. The results revealed that E. faecium SA5 was acid-resistant, bile salt-resistant, and has antibiotic activities against 4 pathogenic microorganisms (Salmonella typhimurium KCTC 3216, Listeria monocytogenes KCTC 3710, Bacillus cereus KCTC 1012, Staphylococcus aureus KCTC 1621). In addition, E. faecium SA5 had tolerance against some antibiotics such as colistin, gentamycin and neomycin. It was also found that E. faecium SA5 possessed bile salt hydrolase activity, which could lower blood cholesterol level. When incubated in 10% (w/v) skim milk as a yogurt starter, E. faecium SA5 caused to decrease pH of the medium as well as increase in viable cell counts. Using TLC and HPLC analysis on the samples incubated in MRS broth, our study confirmed that E. faecium SA5 can produce ${\beta}$-glucosidase, which was capable of converting ginsenoside $Rb_1$ into new ginsenosides $Rg_3-s$ and $Rg_3-r$. It was concluded that E. faecium SA5 possessed a potential of probiotic activity, which could be applied to yogurt manufacture as well as ginsenoside conversion in ginseng.

• Korean Journal of Food Science and Technology
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• v.27 no.4
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• pp.598-604
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• 1995

The contents in large intestine of Sprague Dawley rats fed polygalae radix(Polygala tennuifolia), onion(Allium cepa) and mugwort(Artemisia asiatica)-supplemented diets for 14 days were analysed for changes of major intestinal microflora, activities of ${\beta}-glucosidase\;and\;{\beta}-glucuronidase$ and amounts of putrefactive products such as indole and volatile basic nitrogen. The rats having ingested $5%{\sim}10%$ mugwort water or ethanol extract-supplemented diets showed a significant increase in intestinal bifido-bacteria and a decrease in clostridia and E. coli (p<0.05). And 10% onion juice group also showed a similar beneficial microflora change. In 5% mugwort powder-supplemented group, ${\beta}-glucosidase\;and\;{\beta}-glucuronidase$ activities in the intestinal contents were lowered, but the changes were not significant. Indole contents and pH in this group were significantly low compared with that of control (p<0.05). However, the activities of ${\beta}-glucosidase$ in 5% polygalae radix water extract and 10% onion juice-supplemented group and ${\beta}-glucuronidase\;in\;5%{\sim}10%$ mugwort water and ethanol extract-supplemented group were significantly higher than those of control (p<0.05). The intestinal indole contents of rats were significantly increased by feeding diet with water extract of polygalae radix and ethanol extract of mugwort which had brought comparatively large amount of protein in intestine (p<0.05). However, polygalae radix, onion, and mugwort-supplemented group had no effect on volatile basic nitrogen.

• The Korean Journal of Food And Nutrition
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• v.30 no.5
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• pp.1127-1131
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• 2017

To evaluate the anti-oxidant and anti-tumor potential of the green pepper (Capsicum annuum L. cv. DangZo), total polyphenol content, radical scavenging activities and anti-tumor properties were measured. The total polyphenol content of the 70% ethanol extracts from green pepper (Capsicum annuum L. cv. DangZo) was 30.29 mg gallic acid equivalent/g extract. The DPPH radical and hydroxyl radical scavenging activities of 70% ethanol extracts of green pepper (Capsicum annuum L. cv. DangZo) were documented at 2.87 and 10.55, respectively. For ${\alpha}$-glucosidase and ${\alpha}$-amylase inhibitory activity, 70% ethanol extracts of green pepper (Capsicum annuum L. cv. DangZo) were documented at 35.67% and 58.41% respectively. The green pepper (Capsicum annuum L. cv. DangZo) demonstrated greater capability in terms of anti-neoplastic activity vis-a-vis colon cancer cell lines when compared to other cancer cell lines.s. er (Capsicum annuum L. cv. DangZo) higher activities of anticancer activities on colon cancer cell lines compared to other cancer cell lines.

• KSBB Journal
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• v.14 no.4
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• pp.429-433
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• 1999

$\beta$-Glucosidaes from Cellvibrio gilvus(CG) was successfully overproduced in soluble form in E. coli with the coexpression of GroEL/ES/. Without the GroEL/ES protein, the $\beta$-glucosidase overexpressed in E. coli constituted a huge amount(80%) of total cellular protein, but was localized in the insoluble fraction, and little activity was detected in the soluble fraction. Coexpression of the E. coli GroEL/ES had a drastic impact on the proper folding of the $\beta$-glucosidase; 20% of the overexpressed enzyme was recovered in the soluble fraction in active form. Similar effects of GroEL/ES were also observed on the overexpressed $\beta$-glucosidase from Agrobacterium tumefaciens(AT). And pET28(a)-RGRAR, partially deleted mutant lacking 5-amino acid residues at carboxy teminus also could be folded into an active form when expressed with the molecular chaperonin GroEL/ES, and its activity was higher than that of the without GroEL/ES system, In addition, the synergistic effect of GroEL/ES and the low induction temperature were important factors for solubilization of the inclusion body from overproduced $\beta$-glucosidases.

• Journal of the Korea Organic Resources Recycling Association
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• v.7 no.2
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• pp.73-82
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• 1999

To verify the usefulness of enzyme activity as a index for the stability or maturity of apple pomace composting. the succession of microbial populations using viable count procedure. and Vmax of ${\beta}$-glucosidase and cellobiohydrolase were measured. based on an increase in fluorescence as the nonfluorescent methylumbelliferyl substrates were enzymatically hydrolyzed, leading to the highly fluorescent methylumbelliferyl molecule 4-methylumbelliferone(MUF). The activities of these enzymes in the decomposition of carbohydrates were gradually decreased in the course of the time. Correlation between microbial population and enzyme activity was not significant with exception of fungi. and the fungi were represented in high density. This indicates that the fungi probably play a major role in composting of apple pomace.

• Korean Journal of Soil Science and Fertilizer
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• v.38 no.5
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• pp.281-286
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• 2005

The effect of oyster shell meal, which is made of a simple crushing and alkaline calcium materials, on soil microbial properties, microbial biomass C, N and P contents, and enzyme activities were evaluated in silt loam soil. The oyster shell meal fertilizer was added at the rates of 0, 4, 8, 12 and $16Mg\;ha^{-1}$. Microbial biomass C, N and P contents were significantly increased with increasing application of oyster shell meal. Soil enzyme activities, such as urease, ${\beta}$-glucosidase and alkaline phosphomonesterase were increased significantly by shell meal application, due to increased soil pH towards neutral range and increased nutrient availability in soil. In particular, the increased microbial biomass P content and phosphomonoesterase activities were strongly correlated with available P content in soil. Conclusively, oyster shell meal fertilizer could be a good supplement to improve soil microbial activities.