• Journal of Life Science
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• v.29 no.6
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• pp.688-696
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• 2019

This study investigated changes in triglyceride and cholesterol synthesis and tyrosinase activity induced by ice plant (Mesembryanthemum crystallinum L.) extract, which cannot be stored for long periods of time due to its high moisture content when it was fermented to improve its storage stability. The accumulation of triglyceride and cholesterol in HepG2 cells inhibited the accumulation with a relatively large magnitude in n-butanol and aqueous fractions that generally have high polarity, however, changes in inhibition potency due to the fermentation were not significant. As for the effect to inhibit tyrosinase activity, when L-tyrosine was used as a substrate, the inhibitory activity was the highest for the aqueous fraction at $60.58{\pm}4.03%$ and $63.35{\pm}4.35%$, before and after fermentation, respectively, which amounted to 72% of that of the positive control group (arbutin, $100{\mu}g/ml$). In addition, when L-3,4-dihydroxyphenylalanine (L-DOPA) was used as a substrate, the inhibitory activity was also found the highest for the aqueous fraction at $56.85{\pm}1.57%$ and $59.38{\pm}1.74%$, before and after fermentation, respectively, which amounted to at least 88% of that in the positive control (kojic acid, $100{\mu}g/ml$). Overall, the activity of the fermented ice plant extract was similar or a little higher compared to that of the one without fermentation, indicating that fermentation can be a good approach to improve the storage stability of the ice plant.

• Journal of the korean academy of Pediatric Dentistry
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• v.31 no.3
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• pp.506-515
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• 2004

The objective of this study was to compare the rate of in vitro demineralization of bovine permanent (BP), human deciduous (HD) and human permanent (HP) enamel. Twenty aye flattened and polished enamel samples for each group (BP, HD, HP) were immersed in a demineralizing solution (0.1 mol/L lactic acid, 0.2% Carbopol 907, and 50% saturated hydroxyapatite) for 1, 2, 4 or 8 days. All 25 samples from each group were subjected to Quantitative light induced fluorescence analysis (QLF) and 5 samples from each group were randomly selected for Transverse Microradiography analysis (TMR). Integrated mineral loss (IML) and lesion depth (LD) were determined by TMR. The fluorescence radiance (FR) of sound enamel $(FR_S)$, demineralized enamel $(FR_D)$ were determined by QLF and FR ratio $(FR_D/FR_S)$ was calculated. Bovine enamel samples showed significant correlation between FR ratio and lesion depth(p<0.05) and deciduous enamel samples does not showed significant correlation between FR ratio and lesion depth(p>0.05). Permanent enamel samples showed significant correlation between FR ratio and lesion depth(p<0.05) The constant of demineralization time between FR ratio from regression analysis were as follows: bovine enamel was -4.643(p<0.05) deciduous enamel was -5.421(p<0.05) and permanent enamel was -4.435(p<0.05).

• Journal of the Korean Society of Radiology
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• v.14 no.1
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• pp.61-68
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• 2020

The purpose of this study is to investigate the correlation of blooming artifacts according to dilution ratio of contrast agent on CT angiography images. A total of 10 sets were prepared by differently setting the ratio of contrast media and saline in a ball phantom made by a 3D printer. CT scan images were obtained and reconstructed by MIP and MPR techniques to obtain axial, sagittal and coronal images, respectively. After, the diameter of the ball phantom of the image obtained after the test was measured each 30 times, a total 1800 times. As a result, the dilution of 20:80 in the coronal plane was the smallest (p<0.05). Similarly, when dilute to 20:80 in the sagittal plane of MIP, it was the smallest as 20.39 ± 0.08 mm (p<0.05). Correlation analysis between dilution ratio and measurement size confirmed strong negative correlations in all reconstructed images (p<0.05). In conclusion, the higher the dilution ratio of the contrast agent, the more difficult it is to measure actual blood vessel measurement. Therefore, this study may provide basic data in future studies on actual measurement.

• Journal of Life Science
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• v.15 no.2 s.69
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• pp.267-272
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• 2005

The objective of this study is to suggest the potentialities of nanoliposome composed of ceramide as an anti-irritant against various irritants used in cosmetics. Ceramides are major structural components of the epidermal permeability barrier, which is known to play an essential part in human physiology by not only preventing the loss of water from the body but also protecting the body from external physical, chemical, and microbial insults. According to the results, better effects on reinforcement of skin barrier function and anti-irritation were obtained with nanoliposome composed of ceramide than with dispersed ceramide. And, we performed in vitro skin penetration test using horizontal Franz diffusion cells with skin membrane prepared from hairless mouse to evaluate the influence of nanoliposome composed of ceramide on the skin penetration of lactic acid in formulations. From the results, we found that the anti-irritation effects of nanoliposome containing ceramide were due to reduced penetration rate of irritants. Conclusively, we could develop a new anti-irritation system and apply this nanoliposome composed of ceramide to the final cosmetic products successfully.

• Analytical Science and Technology
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• v.31 no.6
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• pp.219-224
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• 2018

The fruit and stem of Opuntia ficus-indica var. aboten (OFS), a native plant of Jeju Island, are considered a safe food source. Moreover, stem extracts have been previously reported to possess a variety of biological effects (e.g. anti-inflammatory and anti-oxidant, including the ability to partially ameliorate cognitive impairment), suggesting that this plant may have utility as a functional food. The present study investigated whether fermentation by lactic acid bacteria enhances the biological effects of OFS extracts. The acetylcholinesterase (AChE) inhibitory activity of fermented or non-fermented OFS extracts was evaluated, and the content of marker components dihydrokaempferol (DHK) and quercetin-3-methyl ether (3-MeQ) was analyzed using high-performance liquid chromatography. Fermented (relative to non-fermented) OFS extracts exhibited improved AChE inhibitory activity ($IC_{50}=28.35 mg/mL$), with AChE inhibitory activity resulting from fermentation by L. plantarum ($IC_{50}=12.56mg/mL$) exceeding that resulting from fermentation by L. fermentum ($IC_{50}=17.71mg/mL$). Furthermore, fermented (relative to non-fermented) OFS extracts exhibited a 16.7 % increase in DHK content, and 3-MeQ content of OFS extracts fermented by L. plantarum and L. fermentum increased by 28.6 % and 21.4 %, respectively. Therefore, OFS stem extract AChE inhibitory activity, as well as DHK and 3-MeQ content, was enhanced by fermentation with Lactobacillus spp. This suggests that fermented OFS extracts may contribute to prevention or improvement of cognitive impairment. These data are anticipated to be useful in the development of enhanced-efficacy OFS products.

• Korean Journal of Agricultural Science
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• v.13 no.1
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• pp.130-138
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• 1986

In order to obtain the basic data for development of raw pepper homogenates as instant spice, effects of preservatives, packaging materials, storage temperature and period on chemical components of raw pepper homogenates were investigated during storage after sealing up. The results are as follows: 1. Raw pepper homogenates added 15% sodium chloride was effective prominently than raw pepper homogenates on residual contents of acidity, capsanthin and capsaicin. 2. P. V. D. C film was effective than P. E film in sealing of raw pepper homogenates. 3. Decomposition of capsanthin was exceeded at high temperature during the sealed storage of raw pepper homogenates and decomposition of capsaicin was accelerated at initial stage of storage and also it was decreased prominently by adding of sodium chloride. 4. Decomposition of vitamin C during the storage was exceeded at high temperature and it was prominently suppressed by adding of sodium chloride. 5. Increase of total viable cell count and lactic acid bacteia count was prominently suppressed by adding of sodium chloride and its difference for storage temperature was disregarded.

• Food Science of Animal Resources
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• v.33 no.5
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• pp.565-571
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• 2013

An enzyme ${\beta}$-galactosidase or ${\beta}$-galactohydrolase [EC3.2.1.23], commonly called lactase, mediates galacto-oligosaccharide (GOS) synthesis under conditions of high substrate concentrations. Also, lactase hydrolyzes ${\beta}$($1{\rightarrow}4$) lactose into glucose and galactose, the latter is successively transferred to free lactose to make various oligosaccharides via transgalactosylation. GOS is non-digestible to human digestive enzymes and has been used as a functional prebiotics. Among the 24 lactic acid bacteria (LAB) strains used, Lactobacillus paracasei YSM0308 was selected based on its exhibition of the highest ${\beta}$-galactoside hydrolysis activity, and the crude lactase was prepared for examination of reaction conditions to affect the GOS synthesis. Lactase activity was measured with a spectrophotometer using ONPG (o-nitropheyl ${\beta}$-D-galactopyranoside) method. Lactase activity was not detected in the culture supernatant and was mostly present in the cell pellet after centrifugation. Activity of the crude lactase preparation ranges from102 to 1,053 units/mL, with the highest activity determined for L. paracasei YSM0308. Optimal conditions for GOS synthesis are as follows: concentration of whey powder, pH, temperature, and time were 30%, pH 6.5-7.0, $30^{\circ}C$, and 4 h, respectively. The final GOS concentration was 19.41% (w/v) by the crude YSM0308 lactase, which was obtained from strain YSM0308 grown in the 10% (w/v) reconstituted whey-based medium.

• Biomedical Science Letters
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• v.14 no.4
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• pp.219-223
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• 2008

The present study was designed to clarify whether scuba diving at 5 meters of seawater influences cerebral hemodynamics, hematological and biochemical variables. Twenty healthy young men well trained scuba diving participated in this study. The blood flow velocity in the right and left middle cerebral arteries (L-MCAV and R-MCAV), blood pressure (BP), heart rate (HR), CBC and differential count, prothrombin time (PT), activated partial thromboplastin time (aPTT), biochemical variables, D-dimer and interleukin-8 (IL-8) levels were determined before, immediately after scuba diving for 30 min, and after 30 min of rest (Pre-scuba, Scuba and R-30m, respectively). L-MCAV and R-MCAV tended to increase, but the only significant increase was in L-MCAV in Scuba. SBP and HR significantly declined in R-30m compared with those of Pre-scuba and the Scuba. IL-8 levels were elevated in Scuba and R-30m compared with that of Pre-scuba. In Scuba and R-30m, hematological variables except PT and biochemical parameters excluding glucose and lactic acid did not significantly changed in comparison with those of Pre-scuba. PT level at Scuba and glucose level at R-30m significantly declined in Scuba, while lactate level at R-30m increased compared with each in Pre-scuba. However, PT level at Scuba was within a normal range. These results suggest that scuba diving at 5 m of seawater for 30 min has no adverse effects, is safe and useful for improving health. However, further study must be performed to clarify the mechanism of elevated IL-8 level following scuba diving.

• Journal of Food Hygiene and Safety
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• v.15 no.3
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• pp.256-261
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• 2000

Effect of gamma irradiation on quality properties of half·cooked noodle was studied. The noodle were treated with lactic acid(0.1%, w/w), heat(10 min in boiling water) or their combination after cooking for 3 min, and irradiated at 0, 5 and 10 kGy. The noodle were stored at 25。C for 5 weeks and microbial population, Aw, pH, and texture profiles were examined. Fungi were completely eliminated by gamma-irradiation with 5 or 10 kGy does. Number of aerobic bacteria were also decreased by 2 and 4 log cycles with dose of 5 and 10 kGy, respectively. The D10 values of aerobic bacteria were 2.34∼2.95 kGy. Growth of the aerobic bacteria that survived even at 10 kGy of irradiation were significantly inhibited during storage. Acidification of half-cooked noodle was suppressed by gamma irradiation but A${_w}$ were not affected. Stickiness was decreased at the beginning of storage by gamma irradiation but was restored after 3 weeks. The results indicated that the gamma irradiation would be useful to improve quality and storage stability of half-cooked noodle.

• Microbiology and Biotechnology Letters
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• v.8 no.1
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• pp.55-60
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• 1980

Some of the cultural conditions were improved in order to obtain the higher biomass of Lactobacillus bulgaricus NLS-4 which has the higher lactic acid producing activity as well. Among eight media including 11％ non-fat milk medium as a control, the TIP medium was selected. By a batch experiment, the maximum cell concentration could be increased to 1.0$\times$10$^{9}$ cells per $m\ell$ when the organism was grown at 38$^{\circ}C$ for 18 hours with agitation speea of 200 rpm and under the constant level of pH 6.5 con-trolled with 1 N KOH solution in the selected medium. The cell concentration was further increased to 2.3$\times$10$^{9}$ cells per me in the steady state of continuous culture at the dilution rate of 0.17 hr$^{-1}$ for 18 hours.