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Studies on the Formation of L-Threonine by auxotrophic mutants of Brevibacterium flavum (Brevibacterium Flavum의 Auxotrophic Mutants에 의한 L-Threonine 생성(生成)에 관한 연구(硏究))

  • Lee, Kap-Rang;Park, Dong-Cheol
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.16 no.4
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    • pp.251-261
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    • 1987
  • This study was attempted to increase the production of L-Threonine by Brevibacterium Flavum ATCC 14067, To select the strain which produce the highest threonine, mutants ere induced by N-methyl-N'-nitro-N-nitrosoguanidine treatment. The composition of media and cultural condition for its overproduction of threonine were also studied. In a threonine producer, strain B-13(Met-) was the strain producing the highest amount of threonige among methionine, lysine and isoleucine auxotrophs. The following results were obtained. 1. The wild strain and B-13(Met-) produced threonine 1.4mg/ml and 4.86mg/ml , respectively. 2. The optimum composition of medium for producing threonine by Brevibacterium Flavum B-13 was glucose 10%, ammonium sulfate 4%, potassium phosphate monobasic 0.2%, magnesium sulfate 0.05%, biotin $200{\mu}l$, thiamine $300{\mu}l$. Addition of nicotinic acid also led to increase L-threonine production. 3. In addition of organic nutrients to the fermentation medium, peptone n'ere effective and addition of methionine $100{\mu}g/ml$ produced the highest amount of L-Threonine. Aspartic acid and homoserine were also effective when these amino acid were added to the fermentstion medium. 4. Cultural conditon on threonine production by B-16 were investigated. The optimum pH was 7.0-8.0. The highest amount of threnine was produced after 4 days of cultural period.

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Studies on the Sanitation of Potable Water in Farm Areas (목장지역 음용수의 위생학적 조사연구)

  • 박석기;이강문;김성원;임봉택;박성배;이용욱
    • Journal of Environmental Health Sciences
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    • v.19 no.1
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    • pp.44-50
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    • 1993
  • In order to investigate the hygienic conditions of potable water in farm area, we examined the hygienic bacteriological and chemical tests of the 159 waters in the farm areas of Kwangjugun, Namyangju-gun, Yangpyung-gun Paju-gun and Hwasung-gun.The results were as follows: 1. Of the 159 waters, the average numbers of standard plate count and coliform were 920 $\pm$ 250ml and 450 $\pm$ 380/100 ml, respectively. The average pH was 6.74 $\pm$ 0.08, KMnO$_4$ consumption 4.18 $\pm$ 0.23 mg/l, turbidity 0.74 $\pm$ 0.08 degree, NH$_3$-N 0.07 $\pm$ 0.02 mg/l, NO$_3$-N 7.76 $\pm$ 0.48 mg/l, total hardness 101.3 $\pm$ 4.7mg/l, chlorine 18.6 $\pm$ 1.3mg/l, sulfate 12.9 $\pm$ 1.0 mg/l, lead 0.036 $\pm$ 0.003 mg/l, manganese 0.017 $\pm$ 0.003 mg/l, zinc 0.064 $\pm$ 0.005 mg/l, and copper 0.010 $\pm$ 0.001 mg/l, respectively. 2. Of the 159 waters, 84 samples (52.8%) were over 100 per ml of SPC or detected coliform per 100 ml water and 63 samples (39.6%) exceed over physicochemical limited criteria for potable water. NO$_3$-N was the primary item among excess contents of potable water in farm areas. 3. The contents of total hardness, chlorine and NO$_3$-N in Hwasung-gun were higher than those in the other regions, but the numbers of SPC and coliform in Yangpyung-gun and Namyangjugun were higher than those in the other regions. 4. The correlationships among many items were highly significant (SPC, Coliform, KMnO$_4$ consumption NH$_4$-N, NO$_3$-N, KMnO$_4$, Total hardness, Chlorine, Sulfate).

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DPPH Radical Scavenging Effect and in vitro Lipid Peroxidation Inhibition Activity of Portulaca oleracea and Its Active Principles (쇠비름(Portulaca oleracea) 추출물의 DPPH radical 소거능과 in vitro 지질과산화 억제 효과와 활성성분)

  • Lee, Hee-Jung;Lee, Burm-Jong;Lee, Dong-Seok;Seo, Young-Wan
    • 한국생물공학회:학술대회논문집
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    • 2003.04a
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    • pp.668-672
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    • 2003
  • An antioxidative activity of Portulaca oleracea was tested by in vitro experimental models. The antioxidative activities were determined by evaluation the DPPH radical scavenging activity and by measuring lipid peroxide using 2-thiobarbituric acid (TBA). The crude extract was sequentially partitioned with n-hexane, 15% aq. MeOH, EtOAc, n-BuOH, $H_2O$. Among them, a remarkable antioxidative effect was observed in the fractions of EtOAc and n-BuOH. The DPPH radical scavenging effect $(IC_{50}=17.90{\mu}g/ml)$ of the n-BuOH soluble fraction was comparable with that of natural antioxidant, ${\alpha}-tocopherol(IC_{50}=\;6.99{\mu}g/ml)$ and the inhibitory effect of lipid peroxidation in mouse liver homogenate was similar to that of natural antioxidant, L-ascorbic acid at a concentration of 0.1mg/ml to 5mg/ml. From the BuOH soluble fraction yielded two biophenolic glycosides, 3-hydroxy-1-(2-hydroxyethyl)phenyl-4-O-${\beta}$-D-glucopyranoside(1) and 2-(3,4-dihydroxyphenyl)ethyl-O-${\beta}$-D-glucopyranoside(2) using column chromatography and revered-phase HPLC. In particular, the DPPH radical scavenging activity of 2 was comparable to that tocopherol$(IC_{50}=6.59{\mu}g/ml)$.

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Runoff of Trifluralin from Fields in Louisiana (Louisiana의 농장에서 Trifluralin의 유출)

  • ;S.E. Feagley
    • Journal of Environmental Science International
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    • v.5 no.5
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    • pp.585-592
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    • 1996
  • Trifluralin (2, 6-dinitro-N, N-dipropyl-4- (trifluormethyl) benzenamine) was applied preemergent to soybean in plots drained or nondrained, in louisiana. Plots 14.6 ha were arranged to give 1683 g/ha of trifluralin. The half life of trifluralin in the top 15 cm of soil was 42.6 darts and f6.0 days in nondrained plot and drained plot, respectively. The concentrations of trifluralin in surface runoff water and subsurface runoff water were 0.62 ng/ml-0.02 ng/ml and 11.06 ng/ml-0.02 ng/ml, respectively. The concentration of trifluralin in runoff water was smaller than 2 ng/ml for trifluralin of U.S. Environmental Protection Agency advisory. Total loss of trifluralin in runoff water was 0.021 % of applied amount at drained plots during three month after application. Trifluralin was moved hardly in the water. Subsurface drainage -reduced trifluralin losses because concentration of trifluralin in the subsurface runoff water in drained fields was low.

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Quantitative Determination of 4-methylthio-3-butenyl isothiocyanate in Radish Root by RP-HPLC (RP-HPLC법에 의한 무우의 4-methylthio-3-butenyl isothiocyanate의 정량)

  • Kim, Mee-Ree;Rhee, Hei-Soo
    • Korean Journal of Food Science and Technology
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    • v.18 no.6
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    • pp.475-478
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    • 1986
  • RP-HPLC (Reverse phase-high performance liquid chromatography) assay which was introduced to measure quantitatively the amount of 4-methylthio-3-butenyl isothiocyanate in the radish root, proved to be convenient, accurate and reproducible, showing a good linearity between 10 n moles/ml and 120 n moles/ml (r=0.9997). The results of this assay showed that while the isohtiocyanate was hydrolyzed slowly in the basic medium, it decomposed rapidly in the acidic aqueous medium. On the other hand, the isothiocyanate was relatively stable in the organic solvent (65% acetonitrile). Also, it was found that intact root of Korean radish contain 210-420 ${\mu}moles/100g$, based on the measurement with radish homogenate (pH 8.5, 1 min).

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Passive Immunization Approach to Reduce Body Fat in Pigs Using Fat-specific Polyclonal Antiserum

  • Baek, Kyung Hoon;Choi, Chang Weon;Choi, Chang Bon;Lee, Byong Seak
    • Asian-Australasian Journal of Animal Sciences
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    • v.20 no.10
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    • pp.1594-1599
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    • 2007
  • Plasma membrane proteins from pig adipocytes, brain, heart, kidney, liver and spleen were isolated using a 32% sucrose gradient. An adult male sheep was immunized three times at 3-wk intervals with the purified pig adipocyte plasma membrane (APM) proteins. Blood samples were taken from the immunized sheep 12 d after the third immunization. Antiserum showed strong reactivity with APM proteins determined by ELISA, and the reactivity could be detected at dilutions in excess of 1:128,000. Antiserum showed very low binding affinity with proteins isolated from brain, heart, kidney, liver or spleen. Ninety weanling pigs were allocated randomly to three treatment groups and were injected i.p. with 40 ml of antiserum (n = 30) or 20 ml of lyophilized antiserum (21.5 mg/ml; n = 30). A control group (n = 30) received 40 ml of saline, and all pigs were slaughtered at 24 wk of age. The polyclonal antiserum did not change BW or ADG. Carcass percentage of pigs was numerically increased by the antiserum treatment compared with control. Both antiserum treatments did not significantly (p>0.05) affect body composition, including body fat content, relative to the control group.

Strain Improvement by Interspecific Fusion of Streptomyces actuosus DMCJ-49 and Streptomyces minoensis DMCJ-144 producing $\alpha$-Amylase Inhibitor ($\alpha$-Amylase 저해제 생성균 Streptomyces actuosus DMCJ-49와 Streptomyces minoensis DMCJ-144의 종간 융합에 의한 균주 개량)

  • 김지현;최응칠;김병각
    • YAKHAK HOEJI
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    • v.35 no.1
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    • pp.30-37
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    • 1991
  • Streptomyces actuosus DMCJ-49 and Streptomyces minoensis DMCJ-144 produce the .alpha.-amylase inhibitor. Inerspecific protoplast fusion technique was used to increase the productivity of .alpha.-amylase inhibitor. Four auxotrophic mutants were obtained respectively from two strains by N-methyl-N'-nitor-N-nitrosoguanidine(3mg/ml) treatment. The optimum conditions for the protoplast formation of Streptomyces actuosus DMCJ-49 ade was as follows; 1.2% w/v of glycine, 3mg/ml of lysozyme, and 30 min of lysozyme treatment followed by 36 hr. incubation in the protop-last formation medium. In case of DMCJ-144-his those were 1.2%w/v, 3 mg/ml, 30 minutes and 60 hours, respectively. Regeneration was accomplished with hypertonic soft agar medium that contained 0.4M sucrose, 20mM CaCl$_2$, 50 mM MgCl$_2$ and low levels of phosphate. Fusion of protoplasts carrying different auxotrophic markers was achieved by treatment with polyethylene glycol. The optimum concentration of polyethylene glycol 1450 for the production of recombinants was 40%w/v. When the protoplasts was treated with 40% polyethylene glycol for 30 minutes, the frequency of recombinants was 6.5$\times$$10^{-3}$ and the $\alpha$-amylase inhibition activity of $ade^-his^-$ No. 4, which is the fusant with the most improved activity increased from 33 to 125 I.U./ml.

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Effects of Pumpkin Water Extract Supplement on Serum Lipid and Fasting Glucose Levels in Female Collegians (호박찜 추출물의 보충섭취가 여대생의 혈중 지질과 혈당에 미치는 영향)

  • Rho, Sook-Nyung;Yun, Mi-Eun
    • Journal of the Korean Dietetic Association
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    • v.15 no.4
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    • pp.343-355
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    • 2009
  • To elucidate the effect of a 4 week dietary supplementation with pumpkin water extract on serum lipid and fasting glucose levels, 41 female collegians residing in the Gyeonggi area were recruited. The subjects were divided into three groups: placebo-control (PC, n=11), treatment A (TA, 100 ml/day, n=13), and treatment B (TB, 300 ml/day, n=17). Total serum cholesterol, high-density lipoprotein (HDL)-cholesterol, low-density lipoprotein (LDL)-cholesterol, triglyceride (TG), and fasting glucose were analyzed. The average age, height, weight, and body mass index of the subjects were 21.3 years, 161.1 cm, 53.0 kg, and 20.4 $kg/m^2$, respectively. The average total cholesterol, HDL-cholesterol, LDL-cholesterol, TG, and fasting glucose level (mg/dl) were 171.4${\pm}$26.1, 63.5${\pm}$11.4, 92.6${\pm}$22.9, 76.8${\pm}$32.0, and 89.1${\pm}$8.2, respectively. There were no significant differences among the three groups in any measured parameters, and between the pre- and post-study values of the all parameters. The results indicated that the 4 week pumpkin water extract supplementation (100 ml, 300 ml) did not influence the serum total cholesterol, HDL-cholesterol, LDL-cholesterol, TG and fasting glucose level in female collegians.

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Soil Analysis on Prediction of Consolidation Settlement in Marine Clays (항만점토(港灣粘土)의 압밀심하량(壓密沈下量) 예측(預測)을 위(爲)한 토질분석(土質分析))

  • Kwon, Moo Nam;Son, Kwang Sik;Lee, Sang Ho
    • Current Research on Agriculture and Life Sciences
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    • v.4
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    • pp.87-94
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    • 1986
  • This study was performed in order to contemplate their correlations between physical and mechanical properties of the marine clays which were collected from main harbors in Korea. The results obtained are as follows: 1. Most of the soils in experimental districts consist of CH. CL. and ML. and they are considered to be still proceeding. 2. The equations of the relationship between compression index and liquid limit are as, follows: CH : $C_c=0.0137$ (LL-22.60) CL : $C_c=0.0123$ (LL-14.64) 3. The relationship between compression index and initial void ratio appears that the higher the plasticity, the easier the slope of the regression line. The equations are as follows : CH : $C_c=0.431$ ($e_o-0.504$) CH : $C_c=0.471$ ($e_o-0.235$) ML : $C_c=0.641$ ($e_o-0.393$) 4. The equations of the relationship between compression index and natural water content are as follows: CH : $C_c=0.0133$ ($W_n-28.27$) CL : $C_c=0.0225$ ($W_n-23.56$) ML : $C_c=0.0106$ ($W_n-16.42$) 5. The relationship between initial void ratio and natural water content, and compression index is highly positive correlation and the equations are as follows : CH : $C_c=0.301$ ($e_o+0.017W_n-1.05$) CL : $C_c=0.141$ ($e_o+0.0567W_n-1.054$) ML : $C_c=0.421$ ($e_o+0.0214W_n-1.121$) 6. The equations of the relationship between initial void ratio and liquid limit, and compression index are as follows : CH : $C_c=0.36$ ($e_o+0.08LL-0.819$) CL : $C_c=0.269$ ($e_o+0.026LL-0.929$) 7. The cohesion of marine clays is no concerned with the increment of depth. The equations of relationship between cohesion and unconfined compression strength are as follows. CH : qu=1.896C+0.0107 CL : qu=1.849C+0.04.

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Difference in Volume Perception according to Cup Shape in Normal Weight and Overweight Female College Students (정상체중과 과체중 여대생을 대상으로 컵의 형태에 따른 인지량의 차이에 관한 연구)

  • Lee, Myung-Ok;Chang, Un-Jae
    • Journal of the Korean Dietetic Association
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    • v.20 no.1
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    • pp.63-69
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    • 2014
  • The volume perception of water according to cup shape was examined in female college students divided into a normal weight group (<23 body mass index, n=51) and an overweight group (${\geq}$23 body mass index, n=48). The perceived water volume was recorded by participants after they observed the water volume in cups with different shape (highball and tumbler) and with different base height (high base and low base), which contained the same amount of water (150 ml). The normal weight group perceived a water volume of 238.5 ml (highball) and 201.6 ml (tumbler) for the high base cups. The overweight group perceived a volume of 245.6 ml (highball) and 188.8 ml (tumbler). For the low base cups, the normal weight group perceived a water volume of 207.8 ml (highball) and 104.1 ml (tumbler). The overweight group perceived a volume of 202.2 ml (highball) and 100.4 ml (tumbler). Both the normal weight and overweight groups perceived significantly more liquid in the highball cups compared to the tumbler cups. In addition, both groups perceived significantly more liquid in the high base cups compared to the low base cups. However, there were no significant differences in the estimated variance of perceived volume between the normal weight and overweight groups according to the cup shape and cup base height. In conclusion, cup shape and base height potentially affects volume perception. Therefore, modifying cup shape may be used in a weight control program to help control caloric beverage consumption.