• BMB Reports
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• v.30 no.1
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• pp.73-79
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• 1997

This study was designed to investigate the effects of dietary garlic powder on cytochrome P450 enzymes and membrane stability in murine hepatocarcinogenesis initiated by diethylnitrosamine (DEN). Male Sprague-Dawley rats received a single intraperitoneal injection of DEN (200 mg/kg body wt) dissolved in saline. After 2 weeks on a basal diet, animals were fed diets containing 0. 0.5. 2.0. or 5.0% garlic powder for 6 weeks, and were subjected to two-thirds partial hepatectomy. The areas of placental glutathione S-transferase (GST-P) positive foci were inhibited in rats fed with garlic diets. GST-P is the most effective marker for DEN-initiated lesions. Hepatic microsomal lipid peroxidation was significantly decreased in rats fed with 2.0 and 5.0% garlic powder diets compared with that observed in the control animals and hepatic microsomal glucose 6-phosphatase (G6Pase) activity was found to increase significantly in rats fed 0.5 and 2.0% garlic powder diets. Thus as little as 0.5% garlic powder has a positive effect on the stability of hepatic microsomal membranes. p-Nitrophenol hydroxylase (PNPH) activity and the level of cytochrome P450 2E1 protein in the hepatic microsomes from rats fed diets containing 2.0 and 5.0% garlic powder were much lower than those of control microsomes. Rats fed 5.0% garlic powder diets exhibited the lowest P450 2E1 activity and protein levels among groups. Pentoxyresorufin O-dealkylase activity and immunoblot (cytochrome P450 2B1) analyses were not different between groups. However, the levels of cytochrome P450 1A1/2 protein in rats fed 0.5 and 2.0% garlic powder were significantly induced compared to controls. These results suggest that 2.0% garlic powder is effective in inhibiting the areas of GST-P positive foci, modulating certain isoforms of cytochrome P450 enzymes and stabilizing the hepatic microsomal membrane. Thus, the selective modification of cytochrome P450 enzymes and membrane stability by dietary garlic powder may influence areas of GST-P positive foci and chemoprevention of post-initiation of rat hepatocarcinogenesis.

• Journal of Microbiology and Biotechnology
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• v.22 no.1
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• pp.92-99
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• 2012

The optimal physical factors affecting enzyme production in an airlift fermenter have not been studied so far. Therefore, the physical parameters such as aeration rate, pH, and temperature affecting PLA-degrading enzyme production by Actinomadura keratinilytica strain T16-1 in a 3 l airlift fermenter were investigated. The response surface methodology (RSM) was used to optimize PLA-degrading enzyme production by implementing the central composite design. The optimal conditions for higher production of PLA-degrading enzyme were aeration rate of 0.43 vvm, pH of 6.85, and temperature at $46^{\circ}C$. Under these conditions, the model predicted a PLA-degrading activity of 254 U/ml. Verification of the optimization showed that PLA-degrading enzyme production of 257 U/ml was observed after 3 days cultivation under the optimal conditions in a 3 l airlift fermenter. The production under the optimized condition in the airlift fermenter was higher than un-optimized condition by 1.7 folds and 12 folds with un-optimized medium or condition in shake flasks. This is the first report on the optimization of environmental conditions for improvement of PLA-degrading enzyme production in a 3 l airlift fermenter by using a statistical analysis method. Moreover, the crude PLA-degrading enzyme could be adsorbed to the substrate and degraded PLA powder to produce lactic acid as degradation products. Therefore, this incident indicates that PLA-degrading enzyme produced by Actinomadura keratinilytica NBRC 104111 strain T16-1 has a potential to degrade PLA to lactic acid as a monomer and can be used for the recycle of PLA polymer.

• Journal of Microbiology and Biotechnology
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• v.32 no.4
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• pp.437-446
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• 2022

In this study, to obtain icaritin with high pharmacological activities from icariin, which has a content ratio of over 58% in the total flavonoids of Epimedium herb, a special Epimedium flavonoid-glycosidase was produced, purified and characterized from Aspergillus sp.y848 strain. The optimal enzyme production was gained in a medium containing 5% (w/v) wheat bran extract and 0.7% (w/v) Epimedium leaf powder as the enzyme inducer, and strain culture at 30℃ for 6-7 days. The molecular weight of the enzyme was approximately 73.2 kDa; the optimal pH and temperature were 5.0 and 40℃. The enzyme Km and Vmax values for icariin were 15.63 mM and 55.56 mM/h. Moreover, the enzyme hydrolyzed the 7-O-glucosides of icariin into icariside II, and finally hydrolyzed 3-Orhamnoside of icariside II into icaritin. The enzyme also hydrolyzed 7-O-glucosides of epimedin B to sagittatoside B, and then further hydrolyzed terminal 3-O-xyloside of sagittatoside B to icarisiede II, before finally hydrolyzing 3-O-rhamnoside of icarisiede II into icaritin. The enzyme only hydrolyzed 7-O-glucoside of epimedin A or epimedin C into sagittatoside A or sagittatoside C. It is possible to prepare icaritin from the high-content icariin in Epimedium herb using this enzyme. When 2.5% icariin was reacted at 40℃ for 18-20 h by the low-cost crude enzyme, 5.04 g icaritin with 98% purity was obtained from 10 g icariin. Also, the icaritin molar yield was 92.5%. Our results showed icaritin was successfully produced via cost-effective and relatively simple methods from icariin by crude enzyme. Our results should be very useful for the development of medicines from Epimedium herb.

• Journal of Nutrition and Health
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• v.40 no.3
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• pp.199-210
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• 2007

The aim of this study was to investigate the effects of mulberry juice and cake powder on blood glucose and lipid status along with intestinal disaccharidase and erythrocyte antioxidative enzyme system in streptozotocin (STZ)-induced diabetic rats. Sprague-Dawley male rats weighing $100{\pm}10g$ were randomly assigned to one normal group, and eight STZ-induced diabetic groups: control diet group without mulberry juice and cake powders (DM-C), three mulberry juice powder groups (0.5%: DM-0.5J, 1%: DM-1J, 2%: DM-2J) and low mulberry cake powder groups (0.25%: DM-0.25C, 0.5%: DM-0.5C, 1%: DM-1 C, 2%: DM-2C). After three-week feeding of each experimental diet, diabetes was induced by intravenous injection of 50 mg/kg body weight of STZ in sodium citrate buffer (pH 4.3) via tail vein of eight DM groups. Rats were sacrificed at the 9th day of diabetic states. Level of blood glucose was 505 mg/dl in DM-C group but it was 28% and 39% lower in mulberry juice and cake powder fed groups, respectively, than the DM-C group. Activities of maltase, sucrase and lactase in proximal part of small intestine were significantly lower in the mulberry juice and cake powder groups by $42{\sim}47%$ than those of DM-C group. Erythrocytic superoxide dismutase, glutathione peroxidase and catalase activities were significantly reduced by STZ but increased close to normal levels along with less accumulation of thiobarbituric acid reactive substances (TBARS). Serum levels of triglyceride and total cholesterol and HDL-cholesterol by STZ-DM were reduced and increased respectively, to the norma] levels by the mulberry juice and cake powder. Except the levels of TBARS, the effects on the other measurements by the various dietary levels of mulberry juice and cake powder were almost same and the effect of the cake powder was most significant at the lowest level. These results indicate that mulberry juice and cake powders have consityerable hypoglycemic effect and strengthening antioxidant defense systems at the low levels in diabetic state and may be able to reduce diabetic complications.

• Journal of Nutrition and Health
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• v.34 no.5
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• pp.513-524
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• 2001

This study was performed to investigate the effects of dry powders, ethanol extracts and juices of radish and onion on lipid metabolism, lipid peroxidation and antioxidative enzyme activity in rats. Forty-nine male Sprague-Dawley rats weighing 157$\pm$6g were blocked into seven groups according to body weight and raised for four weeks with diets containing 5%(w/w) dry powders of two different vegetables consumed frequently by Korean-radish(Raphanus sativus L.) and onion(Allium cepa L.), ethanol extracts and juices from equal amount of each dry powder. All the powders, ethanol extracts and juices of radish and onion decreased total lipids, triglycerides and total cholesterol concentrations in plasma and liver. Above all, onion ethanol extract decreased them most remarkably. It was thought that organosulfur compounds and flavonoids extracted from onion by ethanol inhibited biosynthesis and absorption of lipid and promoted degradation of lipid. Radish powder also decreased them by increasing fecal excretions of total lipids, triglycerides and total cholesterol most effectively. Catalase and glutathine peroxidase(GSH-px) activities in red blood cell(RBC) were most remarkably increased by radish powder and onion powder respectively. Superoxide dismutase(SOD), catalase and GSH-px activities in liver were most remarkably increased by onion ethanol extract, radish powder and onion ethanol extract respectively. Xanthine oxidase(XOD) activities in liver were most effectively decreased by ethanol extracts of radish and onion. Thiobarbituric acid reactive substance (TBARS) levels in plasma and liver of experimental groups were significantly lower than those of controls. Above all, onion powder decreased them most effectively. It was thought that vitamin E and high flavonoids in onion powder inhibited lipid peroxidation, promoting liver and RBC SOD, catalase and GSH-px activities and inhibiting XOD activities effectively. Flavonoids in onion ethanol extract inhibited lipid peroxidation, promoting three antioxident enzyme activities and inhibiting XOD activities most remarkably. Also flavonoids and high vitamin C in radish powder inhibited lipid peroxidation, promoting liver and RBC catalase most remarkably and inhibiting XOD activities. In conclusion, radish and onion were effective in lowering lipid levels and inhibiting of lipid peroxidation in animal tissue. From these data, radish and onion can be recommended in the treatment and prevention of diseases such as cardiovascular disease and cancer and in delaying aging. As ethanol from onion were most effective in lowering lipid level and promoting three antioxident enzymes, and inhibited lipid peroxidation as did we should try to utilize onion skin which is discarded though reported to have abundant flavonoids. (Korean J Nutrition 34(5) : 513~524, 2001)

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.1
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• pp.74-80
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• 1999

Growth and bacteriocin production by Lactobacillus sp. GM7311 in tofu residue treated with two commercial amylases were investigated. The optimal condition of amylase Ⅰ(liquefied enzyme for sauce) and Ⅱ(multienzyme 2,000) for the enzyme reaction was showed at pH 6.0 and 4.0, respectively. The optimal temperature was 40oC both. At the enzyme dosage 4% and 3% and reaction time 1hr, about 2% of reduced sugar needed bacteriocin production was obtained. The enzymatic treatment of tofu residue enhanced bacteriocin production by lactic acid bacteria, particularly in the tofu residues added 2.0% yeast extract. But, we couldn't see the increment of bacteriocin activity in the tofu residues added other nitrogen sources such as proteose peptone No. 3 and lab lemco powder. Also, in the comparision of amylase I and Ⅱ, bacteriocin activity in the tofu residue treated with amylase Ⅰ was better than that of amylase Ⅱ.

• Applied Chemistry for Engineering
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• v.25 no.1
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• pp.107-112
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• 2014

Using a chlorosulphonated polyethylene rubber solution for a binder of graphite powder and ferrocene for a mediator, a rose leaf tissue-embedded biosensor was built. Linearity on the Hanes-Woolf plot showed the reduction of the substrate was attained through the catalytic power of the rose peroxidase in the experimental range of electrode potential. Furthermore, 10 or more electrochemical parameters demonstrated that the electrode exerts its sensing ability quantitatively. The foregoing gave the full conviction that rose tissue can be used in place of the currently marketed enzyme for the practical use of enzyme electrode.

• Analytical Science and Technology
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• v.22 no.5
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• pp.355-359
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• 2009

An enzyme electrode bound by rubber solution was newly constructed and the test of its practicability were carried out. The binder of carbon powder was styrene-butadiene rubber dissolved in toluene and enzyme source was ground tissue of cabbage root. Volatilization of the solvent made the electrode material possess a mechanical robustness and a fast signal appearance. The electrode showed electrochemically irreversible characteristics and a powerful catalytic power (detection limit=$5.0{\times}10^{-5}M$, S/N=2). The double reciprocal plot of signal current and substrate concentration was ideally linear and the symmetry factor and exchange current density of the electrode used in this work were 0.35 and $4.93{\times}10^{-5}Acm^{-2}$ respectively.

• International Journal of Industrial Entomology and Biomaterials
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• v.33 no.2
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• pp.78-84
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• 2016

The antioxidant activity of silkworm powder treated by proteolytic enzyme was investigated. Total protein content of silkworm power was assayed using BCA, Bradford assays and SDS-polyacrylamide gel electrophoresis (PAGE) with alkaline protease treatment conditions including temperature and pH. The optimum condition of alkaline protease treatment for silkworm powder was found to be $60^{\circ}C$ and pH 7. The alkaline protease treatment resulted in increased contents of free amino acids, total polyphenol and total flavonoid compared to control group. The silkworm hydrolysates showed excellent antioxidant activities in various in vitro models such as 2,2 diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity, 2,2 - azino-bis(3-ethylbenzthiazoline-6)-sulfonic acid (ABTS) radical scavenging activity. These results provide useful information for using silkworm powder as an ingredient in functional foods and for exploiting alkaline protease treatment to improve the extractability and bioactivity of a raw material.

• Journal of the Korean Society of Industry Convergence
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• v.25 no.6_2
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• pp.1009-1015
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• 2022

The purpose of this study was to investigate the effects of protease in Letinus edodes, Agaricus bisporus and Pear powder after freeze drying which has the ratio of 3% on the Tenderness of the Beef Eye of Round muscle. It were marinated in distilled water (Control), 3% Letinus edodes powder (L3), 3% Agaricus bisporus powder (A3), and 3% Pear powder (P3). As a result, enzyme activities were highest in Agaricus bisporus (p<0.001). There are significant difference in pH (p<0.001), color of the beef were slightly different between the C (control) group and the sample groups. The cooking loss showed the lowest value in the control and the highest value in the water holding capacity of Agaricus bisporus. In addition, Agaricus bisporus showed the lowest shear force values than the other sample groups(p<0.001).