• Korean Journal of Veterinary Research
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• v.39 no.4
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• pp.765-771
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• 1999

Unlike most Escherichia coli strains, E coli O157 : H7 didn't ferment sorbitol within 24h of incubation and showed a negative reaction for $\beta$-glucuronidase. We developed a new medium for the rapid isolation of E coli O157 : H7 using sorbitol MacConkey agar with cefixime, potassium tellurite and 4-methylumbelliferyl-${\beta}$-D-glucuronide (MUG) as a primary plating medium. The addition of $20{\mu}g/ml$ of vancomycin in enrichment broth for E coli O157 : H7 inhibited lots of Gram positive bacteria. Three strains (10.3%) of 29 non-O157 E coli strains and 3 strains (8.3%) of 36 Salmonella spp were inhibited at the $0.05{\mu}g/ml$ of cefixime and 23 strains (79.3%) of 29 non-O157 E coli strains and 12 strains (33.3%) of 36 Salmonella spp were inhibited at the $2.0{\mu}g/ml$ of potassium tellurite. But none of the E coli O157 : H7 was affected at these concentration. The addition of MUG at $100{\mu}g/ml$ level to sorbitol MacConkey agar with cefixime and potassium tellurite (CTM-SMAC) aided in the rapid isolation of E coli O157 : H7 from samples by checking sorbitol-negative and $\beta$-glucuronidase negative phenotypes simultaneously. In conclusion, inoculation of a positive in the O157 screening test from enrichment broth on CTM-SMAC appeared to be a rapid, cost-effective and sensitive method for the isolation of E coli O157 : H7.

• Korean Chemical Engineering Research
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• v.46 no.6
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• pp.1039-1042
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• 2008

In order to increase a functionality, OH value, for a recycled polyol prepared from the glycolysis reaction of a waste polyurethane rigid foam(PUR), the effect of an addition of pentaerythritol(PEN, functionality(f)=4) or sorbitol(SOR, f=6) to the its glycolysis reactor on the prepared polyol functionality and the mechanical properties of the polyurethane prepared using it was investigated. The OH values increased from 2.2 for a virgin to 2.8 for the recycled polyol. There was an increase in the mechanical properties including dimensional stability for PUR prepared using the recycled polyol, in which the increased OHs provided higher crosslinking density during PUR synthesis. In addition, the amount of the recycled polyol in the polyol system increased to from 8 to 20 wt% to give better mechanical properties to the PUR.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.5
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• pp.582-586
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• 1999

The processing conditions for producing and edible alginate film from sea tangle were investigated by measuring water vapor permeability (WVP), tensile properties and colors of film. The alginates were extracted with $3\%$ sodium carbonate ($Na_2CO_3$) solution for 5 hrs, and the alginate films were prepared with extracted sodium alginates, D-gluconic acid lactone, $CaCO_3$ and various plasticizers, As the concentration of alginate in making the film was increased, the WVP and elongation of the film were decreased and the tensile strength was increased. The higher amount of plasticizer showed the higher WVP and elongation, and the order of various plasticizers in increasing the WVP and elongation of the film was glycerol, polyethylene glycol, and sorbitol. The addition of sorbitol in the film showed the highest value (89.57) in lightness of Hunter color system and the film added polyethylene glycol had the highest values (-1,12 and 11.4) in redness and yellowness.

• Microbiology and Biotechnology Letters
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• v.25 no.1
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• pp.68-74
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• 1997

The conversion of D-sorbitol to L-sorbose by Gluconobater suboxydans was analyzed, and continuous production of L-sorbose was carried out in immobilized cell reactors. L-Sorbose production by high densities of resting cells was more effective than by conventional batch fermentations. Sorbitol dehydrogenase, an enzyme converting D-sorbitol to L-sorbose, did not suffer from substrate inhibition, but from product inhibition. When L-sorbose production was carried out with Ca-alginate-immobilized cells, about 60 g/l of L-sorbose was obtained. On the other hand, when the corn steep liquor (CSL) concentration of medium was reduced to 0.08%, 80 g/l of L-sorbose was obtained. Outgrowth inside the immobilized carriers was thought to block the pores of the carriers so that substrate could not easily diffuse through the carriers. Continuous production of L-sorbose was well accomplished in a bubble column reactor, and 6. 5 g/l.h of productivity and 81.2% of yield were obtained at a substrate feeding rate of 0.08h$^{-1}$ under the optimum conditions with carrier volume of 55% and aeration rate of 3 vvm.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2006.11a
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• pp.419-422
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• 2006

Improvement of performance of sorbitol model rocket was studied. The rocket designed in this work was compared with the rocket manufactured previously with respect to the shape of body, grain of rocket motor, motor case and recovery system. From this comparative work, it is found that mass ratio is required to be increased and the rocket was designed under safety regulation.

• 한국생물공학회:학술대회논문집
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• 2000.11a
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• pp.665-668
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• 2000

Recombinant Escherichia coli NZN111 ($F-{\Delta}pfl::Cam$ ldhA::Kan) harboring pTrcML, a plasmid containing the E. coli malic enzyme gene, produced considerable amount of malic acid along with the desired product succinic acid. This seemed to be due to the unmatched redox states between glucose and succinic acid. Therefore, a more reduced carbon substrate sorbitol was examined for the possibility of matching the potential during succinic acid production. When NZN111 (pTrcML) was cultured in LB medium containing 20 g/L sorbitol under $CO_2$ atmosphere, 10 g/L of succinic acid was produced. The apparent yield of succinic acid was 1.1 g succinic acid per g sorbitol, which is 85% of the maximum theoretical yield.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.6
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• pp.1251-1255
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• 1999

The sugar alcohols are useful alternatives to sucrose in confections because they provide desirable taste but lessen the potential risks for dental caries. The effects of sugar alcohol and their interaction on starch pasting properties were determined by the viscoamylograph with the concentration of 30%, 20%, 10% sugar alcohol in 1% CMC. The disaccharides, lactitol, maltitol, and isomalt, delayed pasting more than did monosaccharides, sorbitol and xylitol. With regard to the solubility in water, sorbitol and xylitol are more soluble than sucrose, maltitol and lactitol are almost equal and isomalt is less soluble than sucrose. Sorbitol and xylitol were highest on gelatinization. But their retrogradation occurred faster than other sugar alcohols. Lactitol and maltitol decreased gel strength more than did sucrose and other sugar alcohols.

• Korean journal of food and cookery science
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• v.6 no.2
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• pp.59-66
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• 1990

The characteristics of sponge cakes containing sucrose or other sweeteners for diabetes mellitus patients were investigated through physical measurement and sensory evaluation. The results are as follows: The physical properties of cake batters and cakes with sweeteners were different from each other in viscosity, specific gravity, standing height, firmness, and springiness. from the result of sensory evaluation, it was shown that cakes containing sorbitol and fructose had high quality even though they were not as good as cake with sucrose. However, cakes with saccarine and stevioside showed much difference compared with cake with sucrose. The characteristics of sponge cake with combined sweeteners (sorbitol plus stevioside) were compairable to those of sucrose cake. There was little difference in specific gravity. The result of sensory evaluation indicated the combined use of both sweetenes could produce bette cakes than either stevioside or sorbitol. Practical utilization of this cake would be provided under the sensory evaluation on these cakes by diabetes mellitus patients.

• The Korean Journal of Food And Nutrition
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• v.12 no.6
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• pp.608-614
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• 1999

김치의 단맛을 내기 위하여 일반 제조에 이용괴고 있는 sucrose 대신 stevioside나 sorbitoal과 같이 당의 종류를 달리하여 제조한 김치의 이화학적 성분. 미생물의 변화 및 관능적 특서에 미치는 영향을 조사하였다 pH와 적정산도는 stevioside와 sorbitol이 첨가된 처리구가 sucrose 가 첨가된 처리구보다 산의 생성 억제효과가 있는 것으로 나타났다 총균수의 경우 전반적으로 당의 종류와 저장온도와는 관계없이 미생물의 생육 억제효과가 없는 것으로 나타났으나 젖산균의 경우 1$0^{\circ}C$에서는 균의 생육 억제효과는 없는 반면 5$^{\circ}C$에 저장한 김치의 경우 stevioside와 sorbitol이 첨가된 김치는 젖산균의 생육에 억제효과가 있는 것으로 나타났다 관능검사를 실시한 결과 stevioside 첨가된 김치가 sucrose 첨가구에 비하여 기호도에서는 전반적으로 우수한 것으로 나타났다.

• Korean Journal of Veterinary Research
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• v.40 no.3
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• pp.525-531
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• 2000

Verotoxin non-producing E coli O157 strains have been isolated from cattle feces and compared in particular regard to biochemical properties and genotypes with verotoxin-producing E coli (VTEC). E coli O157 : nonH7 strains had different phenotypes in sorbitol fermentation and ${\beta}-glucuronidase$ activity from E coli O157 : H7. Regardless of verotoxin production ability of E coli O157 : H7, uidA gene was uniquely detected from sorbitol and ${\beta}-glucuronidase$ negative E coli O157 : H7. Forty five fecal samples from 6 dairy farms were obtained and VTEC was detected as 15.6% (7 strains) of the samples. Most VTEC isolates were positive for sorbitol fermentation and ${\beta}-glucuronidase$ activity but negative for eaeA gene. This study suggested that cattle could be a reservior for VTEC. However, absence of eaeA gene in VTEC isolates from most of healthy cattle suggested that they might be less virulent than eaeA-positive E coli against human health.