• Journal of Applied Biological Chemistry
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• v.49 no.3
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• pp.82-85
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• 2006

Eucommia ulmoides bark extracts by cold water, boiling water, 100% EtOH, 70% EtOH, 100% MeOH, 70% MeOH and $CHCl_3$ were assayed for their medicinal effects. The antioxidant activity of the extracts ranged from $IC_{50}$ 125.2 to $IC_{50}\;872.7{\mu}g/ml$ in the 1,1-diphenyl-2-picrylhydrazyl (DDPH) free radical-scavenging assay, and cold water extracts had the highest antioxidant activity. $CHCl_3$ extracts had the highest inhibitory effect on angiotensin I-converting enzyme (ACE) giving inhibition of up to 56.4% at a concentration of 1 mg/ml. Extracts in 100% EtOH had the greatest inhibitory effect on $\acute{a}-amylase$ activity ($IC_{50}=174.6{\mu}g/ml$), and 70% MeOH extracts had the greatest inhibitory effect on ${\alpha}-glucosidase$ activity ($IC_{50}=14.0{\mu}g/ml$). Taken together, these results provided the in vitro evidence on the ACE, amylase and glucosidase inhibitory actions of E. ulmoides bark that form the pharmacological basis for its antihypertensive and antidiabetic action.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1998.11a
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• pp.134-134
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• 1998

The modulation of glycosidase activity by inhibitors is of great interest. Such compounds have been shown to be important tools in mechanistic studies on glycohydrolase as well as having promising therapeutic application. An ${\alpha}$-glucosidase inhibitor was isolated from culture filterates of Penicillium sp. The inhibitor was active against ${\alpha}$-glucosidase isolated from yeast and porcine small intestine. However, it showed no inhibition to Aspergillus ${\alpha}$-galactosidase, Escherichia coli ${\beta}$-galactosidase, and jack bean ${\alpha}$-mannosidase. The inhibitor was highly soluble in ether, methanol and chloroform. The inhibitor was purified using silica gel, Sephadex LH-20 column chromatography and reverse-phase HPLC. The inhibitory compound designated PA-7(IC$\sub$50/=35$\mu\textrm{g}$) was obtained as white powder. The structure of PA-7 was determined with spectroscopic data of EI-MS, FAB-MS, $^1$H, and $\^$13/C NMR. The inhibitor has a diketopiperazine moiety.

• Korean Journal of Microbiology
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• v.35 no.2
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• pp.128-132
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• 1999

The effects of diet on the composition of fecal microflora in mouse and the aclivilies of several enzymes in the leces were investigated. Vegetarian dietary groups were found to contain about ten lines higher numbers of Locmbocillus and B$&bacterizml than animal dietary groups. An~rnal dietmy groups were found to contain about 5 tolo times higher numbers of anaerobic Closhidia and Bocieriocles than the vegeterian detary groups. Fccal microbial $\beta$-glucosidase, $\beta$-glucm'onidase, ii-yptophanase and orease activilies in ihe animal dietary groups were shown lo be 30 to 50% hgher than those in h e vegetarian detary groups.

• Korean Journal of Microbiology
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• v.22 no.3
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• pp.167-173
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• 1984

The cellabiase (${\beta}$-glucosidase) gene in a Cellulomonas sp. CS1-1 was cloned into E. coli HB101 using the vector plasmid pBR322, and the expression of the gene in E. coli studied. The chromosomal DNA of the cellulomonas was digested by seveal restriction enzymes, each of which has only one cleaving site in plasmid pBR322. The recombinant plasmid, pSB2, created with Sal I frament, was expressed for the cellobiase gene in E. coli. The recombiant plasmid was estimated to contain 6.4 Kb foreign DNA at the Sal I site of plasmid pBR322 and the inserted DNA was mapped by single and double digestion with several enzymes. E. coli HB101(pSB2) has slowly grown in a mineral liquid medium containing cellobiose as a sole carbon source. The cellobiase activity in the transformed E. coli was 132 units per liter, which is equivalent to one twenty fifth of that in doner strain Cellulomonas sp. CS1-1. The transforned cell with plasmid containing cellulase gene grow well in the LB mediuns. The synthesis of cellobiase in the strain, E. coli HB101 (pSB2), was inhibited by glucose and at high concentration of cellobiose, and induced by cellobiose at low concentration.

• Preventive Nutrition and Food Science
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• v.21 no.3
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• pp.181-186
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• 2016

This study was designed to investigate the inhibitory effect of Gynura procumbens extract against carbohydrate digesting enzymes and its ability to ameliorate postprandial hyperglycemia in streptozotocin (STZ)-induced diabetic mice. G. procumbens extract showed prominent ${\alpha}$-glucosidase and ${\alpha}$-amylase inhibitory effects. The half-maximal inhibitory concentration ($IC_{50}$) of G. procumbens extract against ${\alpha}$-glucosidase and ${\alpha}$-amylase was $0.092{\pm}0.018$ and $0.084{\pm}0.027mg/mL$, respectively, suggesting that the ${\alpha}$-amylase inhibition activity of the G. procumbens extract was more effective than that of the positive control, acarbose ($IC_{50}=0.164mg/mL$). The increase in postprandial blood glucose levels was more significantly alleviated in the G. procumbens extract group than in the control group of STZ-induced diabetic mice. Moreover, the area under the curve significantly decreased with G. procumbens extract administration in STZ-induced diabetic mice. These results suggest that G. procumbens extract may help alleviate postprandial hyperglycemia by inhibiting carbohydrate digesting enzymes.

• Journal of Ginseng Research
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• v.38 no.1
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• pp.47-51
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• 2014

The transformation of ginsenoside Rb1 into a specific minor ginsenoside using Aspergillus niger KCCM 11239, as well as the identification of the transformed products and the pathway via thin layer chromatography and high performance liquid chromatography were evaluated to develop a new biologically active material. The conversion of ginsenoside Rb1 generated Rd, Rg3, Rh2, and compound K although the reaction rates were low due to the low concentration. In enzymatic conversion, all of the ginsenoside Rb1 was converted to ginsenoside Rd and ginsenoside Rg3 after 24 h of incubation. The crude enzyme (b-glucosidase) from A. niger KCCM 11239 hydrolyzed the ${\beta}$-($1{\rightarrow}6$)-glucosidic linkage at the C-20 of ginsenoside Rb1 to generate ginsenoside Rd and ginsenoside Rg3. Our experimental demonstration showing that A. niger KCCM 11239 produces the ginsenoside-hydrolyzing b-glucosidase reflects the feasibility of developing a specific bioconversion process to obtain active minor ginsenosides.

• Journal of the Korean Society of Tobacco Science
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• v.25 no.1
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• pp.70-79
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• 2003

$\beta$ -Glucosidase-catalysed synthesis of glucosides with aromatic alcohols and monoterpene alcohols as accepters and cellobiose as a donor in the presence of various commercial $\beta$ -glucosidases were described. $\beta$ -Glucosidases from Aspergillus niger spp,. Trichoderma spp., Penicillium sup. and bitter almond have been shown to catalyze synthesis of $\beta$ -glucosides of benzyl alcohol, 2-hydroxybenzyl alcohol, 4-hydroxybenzyl alcohol, 2-phenylethyl alcohol, geraniol and citronellol in the presence of cellobiose as sugar donor. Among enzyme preparations tested, each $\beta$ -glucosides prepared from Aspergillus niger were isolated in the pure state by Diaion HP-20 and silica gel column chromatography. The products were identified as $\beta$ -glucosyl products of benzyl alcohol, 2-hydroxyhenzyl alcohol, 4-hydroxybenzyl alcohol, 2-phenyl ethyl alcohol, geraniol and citronellol by spectrometry (UV, IR, $^1$H-NMR, $^{13}$ C-NMR) and enzymatic hydrolysis with $\beta$ - glucosidase. Monoterpene alcohols with a sterically hindered hydroxyl group, such as linalool, $\ell$-menthol and $\alpha$-terpineol were not used as acceptors in transglycosylation reaction.

• Preventive Nutrition and Food Science
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• v.16 no.3
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• pp.236-241
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• 2011

Allium victorialis L. (A. victorialis) is a very popular vegetable in Korea. The most commonly used parts of this vegetable are the bulbs and young leaves. To determine if the mature leaves have any beneficial properties, we investigated antioxidant, anti-${\alpha}$-glucosidase, anti-inflammatory, and anticancer activities of water and ethanol extracts from A. victorialis. Antioxidant activity was evaluated by measuring total phenolic content, DPPH and superoxide radicals scavenging activities. The water extract from A. victorialis ($W{\cdot}A$. victorialis) exhibited higher antioxidant ability than the ethanol extract ($E{\cdot}A$. victorialis). Moreover, the water extract showed strong inhibitory effect on ${\alpha}$-glucosidase. On the other hand, the ethanol extract had greater anti-inflammatory activity on murine macrophage cells (RAW 264.7) and greater anticancer activities against human colon cancer cells (HT-29). These results suggest that mature leaves from E·A. victorialis may have health-enhancing effects.

• Preventive Nutrition and Food Science
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• v.7 no.1
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• pp.62-66
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• 2002

As inhibitors of carbohydrate-digesting enzymes can prevent hyperglycemia that is known to cause many macrovascular complications, they may prove a useful adjunct to hypocaloric diets in patients with type 2 diabetes and obesity. Inhibitory activities of two hundred and fifteen kinds of medicinal herb extracts against $\alpha$-glucosidase (EC 3.2.1.20) and $\alpha$-amylase (EC 3.2.1.1) have been investigated in vitro. Adenophora triphylla, Aneilema keisak, and Morus bombysis significantly suppressed rat intestinal $\alpha$-glucosidase activity iu vitro. Porcine pancreatic amylase was efficiently inhibited by methanol extracts of Epimedium koreanum, Campsis grandiflora and Salvia plebeia. Methanol extract of Epimedium koreanum among the medicinal herbs tested showed the strongest inhibitory activity against porcine pancreatic $\alpha$-amylase with 0.1 mg/ML of $IC_{50}$/. The herb extract also improved glucose tolerance in ICR mice when loaded with 0.9 g soluble starch per kg body weight. Taken together, Epimedium koreanum merits further evaluation as a therapeutic measure.

• 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.