• Korean Journal of Fisheries and Aquatic Sciences
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• v.19 no.3
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• pp.212-218
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• 1986

In order to isolate antioxigenic substrates, the browning reaction products of xylose and various amino acids were analysed by TLC and dialysis. Rf values of browning reaction products of xylose and hydrophobic amino acids separated on silica gel TLC plate were shown in the range of 0.38 to 0.56 and that of basic amino acids was around 0.2. Browning reaction products made from xylose and Trp were separated on TLC into four bands with Rf values of 0.25, 0.55, 0.81 and 0.91 respectively. Among these the bands with Rf values of 0.25 and 0.55 appeared having strong antioxidant activity. The band of Rf 0.55 which showed the highest activity was positive to Prochazka reagent and had an absorption maximum at 275 nm. In dialysis of the xylose-Trp browning reaction products, the undialysed fraction (inner solution) was repsponsible to the antioxidant activity, which was separated into two bands with Rf values of 0.25 and 0.55 on TLC. The inner fractions of the browning products of xylose and His or Arg were also apparent in antioxdant activity.

• Journal of Pharmaceutical Investigation
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• v.17 no.1
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• pp.1-14
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• 1987

To increase the bioavailability of norfloxacin, inclusion complex of antimicrobial agent norfloxacin with ${\beta}-Cyclodextrin$ was prepared and studied by the solubility method, spectrophotometric methods(UV, IR, $^1H-NMR$), differential thermal analysis, powder X-ray diffractometry, the physical properties, the antimicrobial activity, DNA binding and in situ recirculation technique. The conclusions are summerized as following; 1) The inclusion complexation was identified by means of solubility, spectrophotometry(UV, IR, NMR), DTA and X-ray diffraction. 2) The molar ratio of $norfloxacin-{\beta}-cyclodextrin$ complex was 1 : 1. 3) The stability constant of $norfloxacin-{\beta}-cyclodextrin$ complex was $21.5\;M^{-1}$, and both true and apparent partition coefficients of the inclusion complex were larger than those of norfloxacin. 4) The time required to dissolve 60% $(T_{60}%)$ of the inclusion complex was 120 min. in distilled water and in the artificial intestinal juice, while norfloxacin did not reach to 60% dissolution within 120 min. 5) The antimicrobial activity of the inclusion complex against Pseudomonas aeruginosa, Klebsiella pneumoniae and Staphylococcus aureus showed no significant difference compared to that of norfloxacin alone. 6) Studies on binding properties between the inclusion complex and norfloxacin alone to DNA according to equilibrium dialysis showed no significant differency. 7) In situ absorption rates (Ka) of inclusion complex and norfloxacin alone were 0.229 and $0.102hr^{-1}$, respectively.

• YAKHAK HOEJI
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• v.37 no.2
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• pp.149-157
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• 1993

Protein methylase inhibitor which is a modulator of biological methylation has been purified and characterized from porcine liver soluble fraction by cell fractionation, Sephadex G25 chromatography, reverse phase HPLC, size exclusion HPLC. The results are summarized as follows. 1) The purified inhibitor shows apparent homogeneity, as judged by HPLC. 2) A molecular weight of the purified inhibitor which is composed of 18 amino acid residues is about 1,400 daltons. 3) A single absorption peak of ultraviolet spectrum was observed at 260nm. 4) The inhibitor was not inactivated by heating at $100^{\circ}C$ until 60min. and its activity was not influenced by treatment with digestive enzymes, such as trypsin, pepsin, pronase, chymotrypin, lysozyme, DNase, and RNase. 5) The purified inhibitor inhibited protein rnethylase I, II, III and phospholipid methyltransferase activities. 6) The purified inhibitor inhibited noncompetitively protein methylase II from porcine liver, spleen, and testis. 7) The $K_{i}$ values for protein methylase II from porcine liver, spleen, and testis were 300nM, 250nM, 297nM, respectively.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.12 no.1
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• pp.56-61
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• 2002

Porous clay ceramics was fabricated using the surfactant as a foaming agent in the secondary-clay produced at Young-Am area in Chun-Nam province. The concentration of surfactant in ceramic slurry was the key factor controlling the pore characteristics and physical properties of the porous ceramics. The more increase of the surfactant concentration increase the more foaming ability and the stability of foamed layer were improved, but the foaming ability was limited within 6.0 wt% of surfactant because the initial viscosity of the slurry increased with increasing the amounts of surfactant. The formed specimen were sintered at both $1150^{\circ}C$ and $1200^{\circ}C$, the porous ceramics showed 0.9 of specific gravity, 50% of water absorption, 45% of apparent porosity, 14% of shrinkage and 70 kg/$\textrm{cm}^2$ of compressive strength.

• Journal of the Korean Ceramic Society
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• v.20 no.2
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• pp.153-160
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• 1983

This study was carried out to research the change of mineral phases and the characteristics(apparent specific gra-vity water absorption firing shrinkage modulus of rupture thermal expansion and specific dielectric constant) of the sintered bodies manufactured by kaolin and limestone. Samples were composed of the same theoretical composition as it of anorthite and fired up to 145$0^{\circ}C$ Investigated the change and micro-structure of the mineral phases by XRD and SEM the characterisdtics of the sintered bodies by TMA Automatic Capacitance Bridge and etc. The results were as follow. 1. Reactions of sintering are occurred between 860-95$0^{\circ}C$ and 1200-138$0^{\circ}C$ and state of bloating is occurred at 1410-145$0^{\circ}C$ 2. For the inclusion of feldspar and its fine particles of materials the temperature of producing and collapsing is decreased. 3. Pseudo-wollastonite and gehlenite are formed about 95$0^{\circ}C$ 4. At 114$0^{\circ}C$ anorthite are begin to forming and increase continuously to 138$0^{\circ}C$. Above 141$0^{\circ}C$ content of anorthite are decreased. 5. The variations of bending strength with sintering temperature reflect similar trend of sintered contraction and in-crease continuously from 120$0^{\circ}C$. At 145$0^{\circ}C$ reached about 680kg/cm2. 6. Specific dielectric constant$($\varepsilon$_s)$ of specimen sintered at 141$0^{\circ}C$ is 7.12 and that value is most favorable.

• Journal of Microbiology
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• v.35 no.3
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• pp.206-212
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• 1997

Heliobacillus mobilis is a strictly anaerobic Gram-positive bacterium which contains a primitive Photosystem I-type reaction center. The membrane-bound cytochrome $C_{553}$ from the heliobacterium suggested to be the immediate electron donor to the photooxidized pigment (P798+) has been isolated and characterized. The heme protein was visualized as a major component with an apparent molecular size of 17kDa in TMBZ-staining analysis of the membrane preparation and showed characteristic $\alpha$ (552.5 nm), $\beta$ (522nm), and Soret absorption (416 nm) peaks of a typical reduced c-type cytochrome in the partially purified sample. The internal 43 amino acid sequence of the electron donor was obtained by chemical agent and protease treatments followed by N-terminal sequencing of the resulting fragments. The internal sequence carries lots of lysine residues and a Cys-X-X-Cys-His sequence motif which are the characteristics of typical c-type cytochromes. The analysis of the sequence by FAST or FASTA program, however, did not show any significant similarity to other known heme proteins.

• Korean Journal of Remote Sensing
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• v.14 no.3
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• pp.285-294
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• 1998

A bio-optic survey was made in the Yellow Sea in May, 1998 for OSMI cal/val and application project. Optical measurements were made in nine stations. From these measurements, apparent and inherent optical properties such as $K_d$, R, a, and $b_b$ were estimated. The patterns of reflectance indicated that all three major constituents, namely, chlorophyll-a, suspended sediments, and CDOM were active in determining the optical properties in the Yellow Sea. Their relative contribution was different among the stations. All the stations had high backscattering and their values fell in Case 2 category. Although the total absorption was very high, it could not be explained by the level of CDOM concentration. It is suggested that the suspended sediment might be highly absorptive and further study is needed to investigate the optical properties of the suspended sediments.

• Archives of Pharmacal Research
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• v.13 no.3
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• pp.227-232
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• 1990

A Physiologically based pharmacokinetic model was used to describe the distribition and elimination of cefriazone in the rat. To validate the practical application of the model, the effect of cffeine on the model was also examined. The model consisted of eleven compartments representing the major sites for ceftriaxone distribution including carcass which served as a residual compartment. Elimination was represented by renal and hepatic (metabolic biliary )excretion with GI secretion and re-absorption. The drug concentrations in most of the tissues were simulated using flow limited equations while brain levels were simulated using membrane limited passive diffusion distribution. The experimental data were obtained by averaging the concentration of drug in the plasma and tissues of five rats after i. v. injection of cefriazone 100 mg/kg without and with caffeine 20 mg/kg. The data for the amount of ceftriazone excreted in urine and gut contents were used to apportion total body clearance. HPLC with UV detection was used for the assay with 0.1-0.2 $\mu$g/ml sensitivity. The great majority of drug concentrations with and without caffeine show reasonably good agreements to the simulation results within 20%. The effect of caffeine on renal and hepatic clearances was apparent with 18.8% and 18.6% increase in the model values, respectively.

• Korean Journal of Agricultural Science
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• v.49 no.3
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• pp.441-450
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• 2022

This study explored the effects of milk flavor (MF) supplementation on growth efficiency, nutrient absorption, fecal score, and blood profiles in weaning piglets. A total of 80 (21 days old) crossbred ([Yorkshire × Duroc] × Landrace) healthy weaned piglets with an initial body weight (BW) of 7.05 ± 1.22 kg were randomly allotted to one of two nutritive treatments with 8 repetitions and five pigs (2 female and 3 male) per pen. The experiment was divided into 2 phases (d 0 - 21, and d 21 - 42), and the dietary treatments consisted of TRT1, basal diet, TRT2 and basal diet + 1.0 g·kg^-1 MF. At days 21 - 42 and the overall period, the average daily gain (ADG) and average daily feed intake (ADFI) increased (p < 0.05) by receiving the MF added feed. However, MF inclusion did not impact (p > 0.05) the feed efficiency (G : F) throughout the entire experiment. Piglets consuming the MF supplemented diet showed that the apparent total tract digestibility of dry matter (DM), nitrogen (N) and energy (E) did not vary significantly (p > 0.05) between the treatments. All through the experiment, the fecal score and blood profile of the piglets fed the flavor diet also remained unaffected (p > 0.05). In conclusion, MF addition to the diet of the piglets increased their body weight and had no adverse effects on nutrient utilization, fecal score, and blood profile. Thus, MF addition could improve the performance outcomes of weaning piglets.

• Journal of Nutrition and Health
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• v.24 no.2
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• pp.124-131
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• 1991

This study was to examine the effects of dietary protein levels and the sources of protein(animal and plant) on calcium and phosphorus metabo lism in 10 healthy Korean female adults. The 26­d day study consisted of a 6-day adaptation period and lO-day moderate protein(109 N, 550mg Ca) a and IO-day high protein( 14g N, 570mg Ca) pe­r riod. During the experimental period, the subjects w were divided into two groups, either consuming a animal protein diet(75 % animal protein) or plant protein diet(75 % plant protein). Calcium(300 mg) was supplemented to two subjects of each d dict group for the last 4 days. Feces, urine and diet were analyzed nitrogen. calcium and phos­p phorus. The apparent absorption of calcium was significantly increased as the protein intake was inc­r reased from 60g to 90g in animal protein diet. A Average calcium absorption rate was 30% and 46 % from high and moderate levels of animal p protein diet Urinary calcium excretion was not affected by t the amount of the protein intake in both animal and plant protein diet. There was significantly higher urinary calcium excretion(I34mg) in high I level of animal protein diet than that( 83mg) in h high level of plant protein diet. Calcium balance was improved as the protein intake increased and c calcium was supplemented. Phosphorus absorp­t tion was more efficient in the high animal diet(77.81 %) than in the high plant diet(55-65%). The overall results indicate that an increase of protein and calcium supplement in moderate pro­ttein intake can improve calcium balance due to the increase of calcium absorption.