• Journal of Life Science
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• v.21 no.3
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• pp.335-340
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• 2011

Glucose and xylose are the most abundant materials in nature which can be used to produce ethanol by yeast fermentation. Three combinations of cultivation with glucose and xylose were carried out; separated, co-culture, and sequential fermentation with Saccharomyces cerevisiae and Pichia stipitis. In the separated fermentation, S. cerevisiae fermented glucose to produce 14.5 g/l ethanol from 29.4 g/l glucose but hardly used xylose. However, P. stipitis utilized not only glucose but also xylose to produce ethanol 11.9 g/l and 11.6 g/l from 29.4 g/l glucose and 29.0 g/l xylose, respectively. In the mixture of glucose and xylose, P. stipitis fermented both sugars, producing 21.1 g/l ethanol while S. cerevisiae fermented only glucose, producing 13.4 g/l ethanol. In the co-culture and sequential fermentation, the co-culture showed more efficient ethanol productivity with 18.6 g/l ethanol than the sequential fermentation with 12.4 g/l ethanol. To investigate the effect of nutrients in the growth of microorganisms and ethanol production, yeast nitrogen base (YNB) was used in the sequential fermentation with S. cerevisiae and P. stipitis. YNB supplemented some nutrients which S. cerevisiae used up in the broth and the culture showed increased growth rate, increased consumption of xylose, and increased ethanol productivity producing 22.5 g/l ethanol from 54.6 g/l sugar with a yield of 0.41 g/g.

• Journal of Microbiology
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• v.45 no.4
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• pp.318-325
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• 2007

Glucose 6-phosphate dehydrogenase (G6PDH, EC 1.1.1.49) in Deinococcus radiophilus, an extraordinarily UV-resistant bacterium, was investigated to gain insight into its resistance as it was shown to be involved in a scavenging system of superoxide $(O_2^{-1})$ and peroxide $(O_2^{-2})$ generated by UV and oxidative stresses. D. radiophilus possesses two G6PDH isoforms: G6PDH-1 and G6PDH-2, both showing dual coenzyme specificity for NAD and NADP. Both enzymes were detected throughout the growth phase; however, the substantial increase in G6PDH-1 observed at stationary phase or as the results of external oxidative stress indicates that this enzyme is inducible under stressful environmental conditions. The G6PDH-1 and G6PDH-2 were purified 122- and 44-fold (using NADP as cofactor), respectively. The purified G6PDH-1 and G6PDH-2 had the specific activity of 2,890 and 1,033 U/mg protein (using NADP as cofactor) and 3,078 and 1,076 U/mg protein (using NAD as cofactor), respectively. The isoforms also evidenced distinct structures; G6PDH-1 was a tetramer of 35 kDa subunits, whereas G6PDH-2 was a dimer of 60kDa subunits. The pIs of G6PDH-1 and G6PDH-2 were 6.4 and 5.7, respectively. Both G6PDH-1 and G6PDH-2 were inhibited by both ATP and oleic acid, but G6PDH-1 was found to be more susceptible to oleic acid than G6PDH-2. The profound inhibition of both enzymes by ${\beta}-naphthoquinone-4-sulfonic$ acid suggests the involvement of lysine at their active sites. $Cu^{2+}$ was a potent inhibitor to G6PDH-2, but a lesser degree to G6PDH-1. Both G6PDH-1 and G6PDH-2 showed an optimum activity at pH 8.0 and $30^{\circ}C$.

• The Korean Journal of Food And Nutrition
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• v.15 no.2
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• pp.89-96
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• 2002

The adsorption characteristics of sodium chloride into Ca-alginate beads have been investigated and the result were as follows: Sodium chloride uptake by Ca-alginate beads increased with time. The highest uptake volume of sodium chloride was 4.2g after 10 minutes. The uptake volume by Fe, Ca, Ba, and Sr-alginate beads was 5.6g, 4.2g, 4.2g and 4.0g, respectively but in case of Fe-alginate beads, the induced hydrogel beads were very fragile and the strength of Fe-alginate beads were weaker than Ca- and Ba-alginate beads. Mg-alginate bead was not formed and Ca-, Ba- and Sr-alginate beads had a similar uptake volume about 4.2g, respectively. The uptake volume of sodium chloride by CaCl$_2$concentration(0.1M. 0.2M and 1M), curing solution, was 4.8, 4.2g and 4.1g, respectively. The uptake volume by sodium alginate concentration(0.6%, 1% and 2%) was 2.8g, 4.0g, and 4.4g, respectively and Ca-alginate bead size was not effected in uptake sodium chloride. The uptake rate on initial sodium chloride concentration(4%, 8%, 12% and 16%) was 30%, 28%, 27% and 25%, respectively. The uptake rate on basic pH(10.0) was higher than when compared to other neutral pH(6.8) and acidic pH(4.0). The initial uptake velocity of sodium chloride from immobilization beads with salt resistant bacteria was lower than that of non-immobilization beads. The uptake rate of sodium chloride was decreased according to elongation of curing time. Reusability of Ca-alginate beads was possible but according to reutilization, the salt uptake volume of beads was also decreased. The uptake volume of sodium chloride from Doengjang by Ca-alginate beads on time course(3, 6, 12, and 24 hour) was revealed 5g, 6g, 7g and 7g, respectively.

• Microbiology and Biotechnology Letters
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• v.18 no.6
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• pp.591-598
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• 1990

Six species under the basidiomycetes were screened for extracellular tannase (tannin acyl hydrolase EC 3.1. 1.20) production in submerged culture and Lenzites betulina was found to be most effective for the production of tannase. The optimum cultural conditions for tannase production were $25^{\circ}C$, pH 6.0 and 21 days of culture period, The efficient composition of culture medium for the production of tannase was performed in synthetic medium containing tannic acid, 2g; sucrose, 5g; bacto-peptone, 2g; ,$ KH_2PO_4, \;2g,\; MgSO_4.7H_2O \;0.5g,\; CuS0_4.5H_2O$, 2 mg; thiamine HCl, 100 ug and distilled water 100 ml, The tannase produced from Lenzites bdulin*r was 223.3 unit (umole of gaUic acidiml of brothlmin). The tannase had an optimal reaction conditions ofpH 6.0 and temperature of $40^{\circ}C$. The enzyme was stable at temperature below $40^{\circ}C$ and lost its activity by 50% above $60^{\circ}C$. And the stable pH range was 5.5 to 6.0.

• Journal of Nutrition and Health
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• v.34 no.6
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• pp.637-644
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• 2001

The purpose of this study was to examine the effect of exercise and diet control program on nitrogen balance in obese children. The subjects of this study were five obese boys aged from 8 to 12 participating in the control period(C) for 3 days, exercise without energy deficit period(EEN) for one week, and exercise with energy deficit period(EED) far another one week, consecutively. The intensity of the exercise was 60-70% of HRmax and the energy was restricted at 493 kcal/day. Daily mean total energy intake was 2,152 $\pm$ 138kca1, 1,861 $\pm$ 138kca1, and 1,368 $\pm$ 87kca1 for the period C, EEN and EED, respectively. The body weight for EEN and EED decreased compared with the period C by average 1.2 $\pm$ 0.2kg and 1.8 $\pm$ 0.3kg, respectively. Of the body weight loss, the fat mass decreased bur 1.0 $\pm$ 0.3kg and 1.5 $\pm$ 0.5kg and the lean body mass by 0.2 $\pm$ 0.4kg and 0.3 $\pm$ 0.4kg, respectively. Of the daily mean nitrogen consumption was 9.1 $\pm$ 0.7g, 9.1 $\pm$ 0.8g and 7.1 $\pm$ 0.5g, the daily mean nitrogen excretion from feces was 1.3 $\pm$ 0.2g, 0.9 $\pm$ 0.1g and 0.7 $\pm$ 0.1g, and from urine was 6.7 $\pm$ 0.6g, 6.6 $\pm$ 0.5g and 6.7 $\pm$ 0.6g, for the period C, EEN and EED, respectively. Daily mean nitrogen balance excluding nitrogen excretion firm feces and urine indicated + 1.1 $\pm$ 1.0, +1.6 $\pm$ 0.6 and - 0.3 $\pm$ 0.9 for the period C, EEN and EED, respectively. Despite the negative indication during EED, there was no statistical signifiranre. The daily mean creatinine excretion was 0.5 $\pm$ 0.0g, 0.7 $\pm$ 0.1g and 0.6 $\pm$ 0.0g and the creatinine-height index(CHl) was 85.1 $\pm$ 6.7%, 83.8 $\pm$ 6.6% and 81.0 $\pm$ 6.5%, for the period C, EEN and EED, respectively, indicating little significant difference among the periods. Taking above results into consideration, it seems the exercise program conducted for this study did not substantially affect the nitrogen balance of the obese children, and may be used far the body weight control. Howeever, the adequacy of the energy restriction and amount of exercise applied to this study need to be further investigated as the nitrogen balance indicated negative and increasing tendency of the creatinine excretion showed during the EED compared with period C, despite the statistical insignificance.

• KSBB Journal
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• v.9 no.2
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• pp.91-97
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• 1994

In this study, Pullulan Production from whey medium by Aureohsidium pullulans was investigated. When the Pullulan production from whey medium was carried outs final cell concentration was similar to sucrose basal medium but Pullulan concentration was less than 5g/$\ell$. For pullulan production from whey medium, adaptation culture technique was tried on lactose and galactose base medium When the adaptation culture technique was not applied, the maximum concentration of pullulan was 3.4g/$\ell$ for lactose, 2.5g/$\ell$ for galactose. Adapted strains produced 10~12g/$\ell$ from lactose, 10~11g/$\ell$ from galactose. The pullulan production from lactose basal medium was 13.5g/$\ell$ for lactose adapted strains and 18.6g/$\ell$ for galactose adapted strains. When the adapted strains were inoculated on whey medium, maximum pullulan production was obtained at initial pH 3.0.

• Korean Journal of Organic Agriculture
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• v.10 no.4
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• pp.61-67
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• 2002

The effect of the Penicillium sp. PS-113 with high phosphate solubilizing activity and Lactobacillus sp. was studied on cucumber growing test in green house. Inoculation of Pemicillium sp. Ps113 $5.0{\times}10^6$cfu/ml and Lactobacillus sp. $6{\times}10^6$cfu/ml were longer than control about 3cm length of cucumber. The average weight was also increased 89.2g more than control. Total product of cucumber was 10,681.7g and it was increased 4517.3g as compared to control. Thus, Inoculations of high phosphate solubilizing microorganism increased in productivity on cucumber.

• Korean Journal of Veterinary Research
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• v.14 no.2
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• pp.173-177
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• 1974

Thirty of healthy non-pregnant Holstein cows being raised in the vicinity of Daejeon, which had been delivered of calves 4 to 6 times since they were imported to Korea, were selected with the purpose of serum chemical analysis. Total protein, albumin, globulin, total cholesterol, urea nitrogen and glucose and A/G ratio were investigated. The results of present investigation were summarized as follows: 1. Ranges and mean values (with standard error) of total protein, albumin and globulin were 6.87~8.58g/100ml, $7.75{\pm}0.60g/100ml$; 2.6~3.5g/100ml(37.1~45.0%), $3.26{\pm}0.27g/100ml$(40.1%); and 3.78~5.48g/100ml(55.1~64.6%), $4.51{\pm}0.43g/100ml$(58.1%), respectively. 2. Range and mean value (with standard error) of A/G ratio were 0.52~0.86 and 0.73~0.093. 3. Range and mean value (with standard error) of glucose were 35~50mg/100ml and $45.2{\pm}9.1mg/100ml$. 4. Range and mean value(with standard error) of total cholesterol were 122~228mg/100ml and $194.6{\pm}11.1mg/100ml$. 5. Serum urea nitrogen showed that the range of 10.5~15.1mg/100ml and the mean value(with standard error) of $12.7{\pm}1.5mg/100ml$.

• Nutrition Research and Practice
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• v.4 no.6
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• pp.470-476
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• 2010

The resistant dextrin NUTRIOSE$^{(R)}$, developed from starch, is expected to act as a prebiotic. The aim of this study was to determine the effects of NUTRIOSE$^{(R)}$ on cecal parameters, short-chain fatty acid (SCFA) concentrations, and fecal excretion in rats. In an initial experiment, twenty-four male Fischer F344 rats were randomly assigned to one of the following four treatments for 14 days: G0 (control diet), G2.5 (control diet+2.5% of dextrin), G5 (control diet + 5% of dextrin), and G10 (control diet + 10% of dextrin). After 14 days, total cecal weight, cecal content, and cecal wall weight were significantly increased in G5 and G10 compared to G0. At the same time, cecal pH was significantly lower in G10 compared to G0. Total SCFA concentration was significantly higher in G10 than in G5, G2.5, and G0, and significantly higher in G5 than in G0. Acetate, butyrate, and propionate concentrations were significantly increased in G5 and G10 compared to the controls. In a second trial based on a similar design, eighteen male Fischer F344 rats were treated with a control diet supplemented with 5% of dextrin or 5% of fructo-oligosaccharide. The results obtained with NUTRIOSE$^{(R)}$ were similar to those obtained with the fructo-oligosaccharide. In a third experiment, two groups of 5 Fischer F344 rats were orally treated with 100 and 1,000 mg/kg NUTRIOSE$^{(R)}$, respectively, and from 18% to 25% of the dextrin was excreted in the feces. The results of these three studies show that the consumption of NUTRIOSE$^{(R)}$, by its effects on total cecal weight, cecal content, cecal wall weight, pH, and SCFA production, could induce healthy benefits since these effects are reported to be prebiotic effects.

• Biomolecules & Therapeutics
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• v.13 no.2
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• pp.123-126
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• 2005

The single dose toxicity of 3-methoxy-6-allylthiopyridazine (K-6) was studied with Sprague-Dawley rats. K-6 was administered orally with dosages of 4.0, 3.0, 1.5, 1.0, 0.5, 0.25 and 0.1 g/kg to the rats. We observed daily the number of death, clinical signs, body weights and gross findings. All rats (6) were dead within a day after administration when doses of 4.0and 3.0 g/kg were administered. When dose of 2.0 g/kg was administered, 2 rats among 3 rats were dead. Any significant toxicity below 1.5g/kg of K6 was not observed when the different doses of 1.5, 1.0, 0.5, 0.25 and 0.1 g/kg were administered to 6 rats respectively.