• Bulletin of the Korean Chemical Society
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• v.32 no.9
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• pp.3323-3326
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• 2011

Various aldoximes and ketoximes were efficiently reduced to their corresponding amines with $NaBH_3CN$ in the presence of $MoCl_5/NaHSO_4{\cdot}H_2O$ system. Reduction reactions were carried out in refluxing EtOH or DMF within 0.3-3.8 h to afford the amines in high to excellent yields.

• Journal of the Korean Chemical Society
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• v.51 no.4
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• pp.346-351
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• 2007

Efficient stereoselective synthesis of α,β-Unsaturated acids, α-Cyanoacrylonitriles and α-Cyanoacrylates has been carried out in the presence of NaHSO4·SiO2 under solvent?free conditions with an E-geometry.

• Bulletin of the Korean Chemical Society
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• v.25 no.7
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• pp.1075-1077
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• 2004

• Journal of the Korean Society of Food Science and Nutrition
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• v.17 no.3
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• pp.198-204
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• 1988

This study was aimed at obtaining elementary data on enzymatic browning of potato and potato products and examining the inhibitory method of browning. Therefore, we extracted polyphenol oxidase from potatoes(Solanum tubersum L.), and investigates its general properties and inhibiting effects of its activity with the different concentrations of sulfites($Na_2S_2O_4,\;Na_2SO_3{\cdot}7H_2O,\;NaHSO_3$). The optimum pH and temperature of polyphenol oxidase were observed to be 6.5 and $37^{\circ}C$ respectively. The polyphenol oxidase at PH5 was very stable, and the activity of polyphenol oxidase between pH $5.0{\sim}9.0$ was estimated to be relatively high, showing $72{\sim}75%$ of its activity at pH5. The polyphenol oxidase was very stable when heated at $40^{\circ}C$ for one hour, and almost 50% of enzyme activity was decreased when heated at $70^{\circ}C$ for twelve minutes. At 0.1mM concentrating of sulfites the relative activity of polyphenol oxidase was 98% in all the three cases of sulfites. Thus sulfites at 0.1mM concentration was found to have little inhibiting effect on polyphenol oxidase activity. At 1mM concentration of sulfites $NaHSO_3$ showed the lowest 36% relative activity among the three. At 5mM concentration of sulfites, the relative activity of $Na_2SO_3{\cdot}7H_2O$ was the lowest 14%.

• KSBB Journal
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• v.22 no.5
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• pp.288-296
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• 2007

Monascus pilosus (KCCM 60160) in submerged culture was optimized based on culture medium and fermentation conditions. Monacolin-K (Iovastatin), one of the cholesterol lowing-agent which was produced by Monascus pilosus may maintain a healthy lipid level by inhibiting the biosynthesis of cholesterol. Plackett-Burman design and response surface method were employed to study the culture medium for the desirable monacolin-K production. As a result of experimental designs, optimized production medium components and concentrations (g/L) were determined on soluble starch 96, malt extract 44.5, beef extract 30.23, yeast extract 15, $(NH_4)_2SO_4$ 4.03, $Na_2HPO_4{\cdot}12H_2O$ 0.5, L-Histidine 3.0, $KHSO_4$ 1.0, respectively. Monacolin-K production was improved about 3 times in comparison with shake flask fermentation of the basic production medium. The effect of agitation speed (300, 350, 400 and 450 rpm) on the monacolin-K production were also observed in a batch fermenter. Maximum monacolin-K production with the basic production medium was 68 mg/L when agitation speed was 500 rpm. And it was found that all spherical pellets (average diameter of $1.0{\sim}1.5mm$) were dominant during fermentation. Based on the results, the maximum production of 185 mg/L of monacolin-K with the optimized production medium was obtained at pH (controlled) 6.5, agitation rate 400 rpm, aeration rate 1 vvm, and inoculum size 3%.

• Korean Journal of Food Science and Technology
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• v.20 no.4
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• pp.576-584
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• 1988

Neutral detergent fiber(NDF) were extracted from the Nampung, Milyang #23, Whasung and Jinhung varieties of rice by neutral detergent fiber method. To determine the properties of NDF three factors were measured : water-binding capacity(WBC), Fe-binding capacity and sodium taurocholate binding with NDF. The average WBC of NDF was $5.60{\pm}0.87gH_2O/g$ NDF, and the average Fe-binding capacity ranged from 24.63% at pH 5.0 to 19.6% at pH 6.0 and 48.98% at pH 7.0. Binding of sodium taurocholate with NDF was determined in vitro using C-14 labeled sodium taurocholate at 100M sodium taurocholate concentrations. NDF binding of Jinhung was 27.87 while Nampung, Milyang #23 and Whasung measured 32% each. When sodium taurocholate concentrations were raised from $40{\mu}M\;to\;240{\mu}M$ the tendency of binding increased as the concentrations increased, but not linearly.

• Korean Journal of Food Science and Technology
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• v.20 no.5
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• pp.674-682
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• 1988

Total lipids from the roe, muscle and viscus of L. carinata were analyzed for lipid composition by column chromatography, thin-layer chromatography and gas-liquid chromatography. The roe lipids were characterized by a high level of wax esters (63.1%) and a low proportion of trigiycerides (9.9%). The viscus lipids also contained wax esters (32.8%) as its main component, followed by free fatty alcohols and acids (23.5%). On the other hand, the muscle lipids were found to contain a large amount of triglycerides (66.1%) with a trace of wax esters. The main fatty alcohol component of roe and viscus wax esters was C16:0 alcohol (53.0%; 61.7%), accompanied by C18:1 alcohol (10.2%) in the former and by C15:0 alcohol (8.8%) in the latter. Considerable amounts of odd-numbered fatty alcohols were found in both wax esters. On the other hand, the fatty acids of the roe and viscus wax esters contained a high percentage of monounsaturated (49.7%-56.6%) consisting of C16:1, C18:1 and C17:1 acid, and a significant amount of polyunsaturated (41.2%-32.9%), particularly C20:5${\omega}$3. The fatty acid components of triglycerides and phospholipids were different among the tissues tested, especially between roe and muscle or viscus. The fatty acid compositions of free fatty acids from the muscle and viscus were characterized by a higher level of polyunsaturated fatty acids (46.0-34.3%) compared to those of triglycerides 'in the roe, muscle and viscus (28.4%, 19.4% and 19.2%).