• Korean Journal of Food Science and Technology
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• v.33 no.3
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• pp.378-383
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• 2001

Formation of superoxide anion $O_2\bar{{\bullet}}$ in the autoxidation of L-ascorbic acid (AsA) in the presence of heavy metal ions were determined. The generation of $O_2\bar{{\bullet}}$ was studied by using superoxide dismutase (SOD) in aqueous and buffer solution, and using nitro bule tetrazolium (NBT) in methanol solution. The remaining amount of AsA was significantly higher in the presence of SOD than in its absence. It suggested that SOD stabilizes AsA in aqueous and buffer solution because of scavenging $O_2\bar{{\bullet}}$ formed during the autoxidation reaction of AsA in the presence of heavy metal ions. NBT has an absorption maximum at about 560 nm in methanol solution. The absorbance at 560 nm increased during the oxidation of AsA, suggested the formation of $O_2\bar{{\bullet}}$in methanol solution. Thus, the formation of $O_2\bar{{\bullet}}$ was confirmed during the autoxidation of AsA not only in aqueous solution but also in methanol solution in the presence heavy metal ions.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.31 no.2
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• pp.272-277
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• 1998

Filtering rates of two farming ascidians Styela clava and S. plicata, and of a farming mussel Mytilus edulis were experimentally investigated with reference to effects of water temperature and size. Absorptiometric determinations of filtering rates were carried out in a closed system with experimental animals being decreased indicate dyes neutral red. Optical density (OD) of 440 nm in path length 22 mm cell used as the indication of food particles absorption was appeared directly in proportion with the concentration of neutral red dyes. The filtering rate F is calculated by Kim's equation $F\;=\;V(1-e^{-z})$, where V is the water volume ($\ell$) in the experimental jar, and Z is the decreasing coefficient of OD as meaning of instantaneous removal speed as In $C_t\;=\;In\;C_{o}-Z{\cdot}t$, in this formula $C_t$ is OD at the time t. Filtering rate of S. clava increased as exponential function with increasing temperature while not over critical limit, and the critical temperature for filtering rate was assumed to be between $28^{\circ}C$ and $29^{\circ}C$. In case of S. plicata, the critical temperature was to be below $13^{\circ}C$, and through the temperature range $15\~25^{\circ}C$ appeared a little difference in level even though with significant. M. edulis was not appear any significant effects by water temperature less than $29^{\circ}C$. The model formula derived from the results is as below, where F is filtering rate (${\ell}/hr/animal$), T is water temperature ($^{\circ}C$), and DW is dry meat weight (g) of experimental animal. $$S.\;Clava;\;F\;=\;e xp\;(0.119\;T-4.540)\;(DW)^{0.6745},\;T<29^{\circ}C$$) $$S.\;plicata;\;F\;=\;e xp\;(A_t)\;(DW)^{0.5675},\;(13^{\circ}C $$[A_t =-8.56+0.6805\;T-0.0153\;T^2]$$ $$M.\;edulis;\;F\;=\;0.3844\;(DW)^{0.4952},\;<29^{\circ}C$$)

• Food Science and Preservation
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• v.13 no.6
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• pp.720-725
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• 2006

This study was conducted to investigate extracting solution effect on the chemical compositions in different parts of Korean mountain Ginseng. Water, 80% EtOH and 80% MeOH are used as extraction solutions, and extracting conditions were 2 hr at $85^{\circ}C$ in water bath. The Brix(%) of the extract were ranged from $0.42{\sim}22.58%$, 80% EtOH extract for leaf is the highest level as 22.58%. The pH ranges of the extracts were $4.43{\sim}7.41$ and brown color of the extract was the highest with 1.803 in 80% EtOH extract for leaf, respectively. In case of hunter's color value of the extract, L value is the highest with 24.35 in 80% EtOH extract of seed, a and b value were the highest with 0.41 in 100% water extract of leaf and 3.69 in 80% MeOH extract of stem. Sucrose is the major free sugar of the extinct it highest content with 3673 mg% in 80% MeOH extract of mot and fructose is the highest with 1897 mg% in 80% MeOH extract of leaf, Major organic acids are identified as malic, tartaric and citric acid, and total organic acid content is the highest with 5,254 mg% in 80% MeOH extract of leaf and 1,527 mg% in 80% EtOH extract of leaf, The extracted major minerals ate P and K, P content highest with 15,563 ppm in 100% water extract of stem, K is 4,952 ppm in 80% MeOH extract of leaf, and Ca is the highest with 3,052 ppm in 1011% water extract of leaf. These results suggest that extracting solvent (80% MeOH) is concerned with the extract preparation of Korea Mountain Ginseng.

• Korean Journal of Plant Resources
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• v.26 no.4
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• pp.411-416
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• 2013

This study was conducted not only to analyze ${\alpha}$-glucosidase inhibition activity with fronds and rhizomes of nine Pteridophyte species, but also to select the plant materials suitable for natural ${\alpha}$-glucosidase inhibitor. Harvested rhizomes and fronds were washed, freeze-dried and grinded. After conducting ultrasonification extraction for 30 minutes in ultrasonic water tank with 100% methanol solvent, and vacuum filtration, ${\alpha}$-glucosidase inhibition activity was measured. Acarbose was used as the positive control. After mixing $100{\mu}L$ of 0.7 unit ${\alpha}$-glucosidase enzyme solution into $50{\mu}L$ of extract and reacting them at $37^{\circ}C$ for 10 minutes, $50{\mu}L$ of 1.5 mM ${\rho}$-NPG solution was taken and reacted at $37^{\circ}C$ for 20 minutes. The reaction was stopped with 1 mL of 1 M $Na_2CO_3$ and absorbance was measured in 405 nm. With the regression analysis, the content of solubility solids (the value of $IC_{50}$) which can inhibit 50% of 0.7 unit ${\alpha}$-glucosidase solution's activity was investigated. The frond ($IC_{50}=14.00{\sim}913.33{\mu}g{\cdot}mL^{-1}$) and rhizome extracts ($IC_{50}=12.93{\sim}205.84{\mu}g{\cdot}mL^{-1}$) of nine Pteridophyte species showed higher ${\alpha}$-glucosidase inhibition activity in comparison with acarbose ($IC_{50}=1413.70{\mu}g{\cdot}mL^{-1}$). The extracts of fronds and rhizomes showed higher value than acarbose by 1.55~100.98 and 6.87~109.33 times each. Especially, ${\alpha}$-glucosidase inhibition activities of Pyrrosia lingua in fronds and Osmunda cinnamomea var. fokiensis in rhizomes were the highest. The necessary biomass of fronds and rhizomes for inhibiting 50% of ${\alpha}$-glucosidase activity showed the lowest value, 0.35, 0.27 mg each, in O. cinnamomea var. fokiensis. $IC_{50}$ value of P. lingua was the highest among fronds of nine Pteridophyte species, but content of soluble solids was 2.4 times less than O. cinnamomea var. fokiensis. So frond of O. cinnamomea var. fokiensis is more economic in comparison with P. lingua. As the result of this study, O. cinnamomea var. fokiensis showed high ${\alpha}$-glucosidase inhibition activity even with small biomass. Therefore it was considered to be high-valued economic material as natural ${\alpha}$-glucosidase inhibitor.

• Journal of the Korean Chemical Society
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• v.44 no.5
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• pp.422-428
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• 2000

Optimum analytical conditions of the aluminium ion were established by flow injection analysis. Eriochrome Cyanine R(ECR) dye reacts with the aluminium ion at pH 6.0 to form a complex that exhibits maximum absorption at 535 nm. Reaction conditions including the mixing and the reaction coil length, the concentration and the pH of the buffer solutio, temperature, and injection loop volume were optimized to intro-duce this reaction into flow injection analysis. The results were as follows. A mixing coil length of 0.5 m and a reaction coil length of 4.0 m, the pH 6.0 and 1M of acetate buffer solution, the ECR concentration of 0.56 mM, the reaction temperature of 40$^{\circ}C$, the injection loop volume of 300${\mu}L$ were chosen as optimum conditions. Under these conditions the detection limit of the aluminiumion was less than 0.05 mg/L and the repeatability was better than 1%. A sampling frequency of 24 times for an hour was achieved. Interfering ions such as $F^-$, HP$O_4^{2-}$, $Fe^{2+}$, $Fe^{3+}$, $Mn^{2+}$, and other anions were tested, interference did not occur up to 1,000mg/L of ion concentration and up to 2,CO0mg/L of sulfate ion con-centration. This method was applied for the determination of aluminium ion in tap water and ground water of Jeonju and the Gochang area. The results showed that the aluminium residual in tap water of the Jeonju area was at a mean of 0.478mg/L and that in tap water of the Gochang area was at a mean of 0.278mg/L. Aluminium ion residual of the tap waters in the Jeonju area was higher level than that in the Gochang area. Aluminium residual in the ground water of the Jeonju area was 0.386 mg/L and was lower compared to 0.564 mg/L for the Gochang area.

• Food Science and Preservation
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• v.19 no.2
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• pp.294-300
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• 2012

The anti-oxidant properties of $Lactuca$ $indica$ were determined using in-vitro assay systems. The vitamin C contents of the leaf and root extracts were 24.14 and 0.38 mg/100 g, respectively. The total polyphenol contents of the leaf and root extracts were 42.8 and 7.66 mg/g, and their flavonoid contents were 23.09 and 0.77 mg/g. The leaf extract showed higher DPPH and ABTS radical scavenging ability than the root extract at all the extract concentrations. Especially, the ABTS radical scavenging ability of the leaf extract was 92.3% at a concentration of 5 mg/mL. The reducing power was increased with the increase in the concentration of extracts, and the leaf extract had a higher reducing power than the root. The $Fe^{2+}$-chelating ability of the leaf and root were 97.2% and 34.3% at 14 mg/mL, respectively. The $IC_{50}$ values of the leaf for DPPH, its ABTS radical scavenging ability, and its $Fe^{2+}$-chelating ability were 0.19, 2.7, and 6.27 mg/mL, respectively, and the leaf extract showed lower $IC_{50}$ values than root extract. These results show that the $L.$ $indica$ leaf extract contained high amounts of anti-oxidative compounds and had higher anti-oxidant activity levels than the root extract. It is suggested that Lactuca indica is very high in availability as a functional food and in its materials.

• Journal of Life Science
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• v.24 no.3
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• pp.242-251
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• 2014

The objective of this study was to isolate a photosensitizer from Pueraria thunbergiana leaves that induces apoptosis in SK-HEP-1 cells. Column chromatography and thin layer chromatography were used to isolate active compounds from extracts of P. thunbergiana leaves. The structures of the isolated compounds were determined by 1D-NMR, 2D-NMR, and FAB-mass spectroscopy. A substance, named M4-3, was purified from the leaves of P. thunbergiana using various chromatography methods, and the absorbance of the substance was measured. The absorbance was highest at 410 nm, suggesting that the M4-3 substance was a different compound from chlorophyll a and b, which absorb at 410, 502, 533, and 607 nm. Further analyses revealed that the M4-3 compound was a $13^2$-hydoxy pheophorbide, a methyl ester with a molecular weight of 662. M4-3 was identified as a derivative compound of pheophorbide, with a structure that magnesium comes away from the porphyrin ring. The results of the analysis of the cytotoxicity of the M4-3 substance against the SK-HEP-1 cells revealed that it inhibited rates of cell growth by 40% and 80% at a concentration of 0.04 ${\mu}M$ and 0.08 ${\mu}M$, respectively. The M4-3 compound was found to be a photosensitizer for cytotoxicity because it was appeared only in light condition as examining activity in different irradiation conditions (light condition and nonlight condition) under the same concentration. Analysis of morphological changes in the cells following cell death induced by exposure to the M4-3 substance reveled representative phenomena of apoptosis (nuclear condensation, vesicle formation, and fragmentation of DNA). The induction of apoptosis was attributed to the compound's photodynamic activity.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.4
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• pp.765-773
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• 2000

The degradation of humic acid using $TiO_2$ coatings was studied, $TiO_2$ coatings were prepared by dip-coating method. Sol solutions for coating were prepared by mixing the gel, which can be produced by the reaction of $TiOCl_2$ and $NH_4OH$ solution, and hydrogen peroxide solution, and hydrolysis of titanium tetraisopropoxide (TTIP). It was shown from XRD that coatings from sol aged at $100^{\circ}C$ for 18h with titanium peroxo solution were crystallized to anatase in the range of temperatures of $25^{\circ}C$ to $500^{\circ}C$. In contrast, those coated from TTIP were crystallized to anatase at temperature above $400^{\circ}C$. So the sols originated from $TiCl_4$ can be applied for not only on the heat-resistance substrates but on the plastic substrates. Thickness and the quality of the films were dependent on the withdrawing speed, the concentration of sol, and the number of coating. The films showed various interference colors depending on the thickness of them. In the case that the films coated 2 times at withdrawing speed of 2.5cm per minute by 0.2M sol, the films had a transparent light blue color with thickness of around 50nm. It was known from the result of photo-degradation by $TiO_2$ coatings using humic acid that the removal efficiency of $COD_{cr}$ was over 85% after illumination of $UV/H_2O_2$ for 40min. and that of UV/VIS absorbable materials was over 95%.

• Korean Journal of Food Science and Technology
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• v.34 no.5
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• pp.762-769
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• 2002

As a preliminary test for defining intact yellow croaker pigment, the pigment was analyzed by column chromatography and UV-vis spectrophotometry. All maximum absorbance wavelengths commonly showed three maximum absorbance ranges, similar to those of carotenoid, suggesting that the tested pigment may be carotenoid. We detected total six peak RT values in the chromatogram through PDA-HPLC under gradient mode (behavior A at 10% for initial 2 min and changed to behavior B for 60 min). Most pigments were detected at the peak with 3.27 RT value. Because seven peaks were detected under gradient mode and three under isocratic mode [methanol : methylene chloride (90 : 10, v/v)], gradient mode was determined to be more appropriate for quantitative analysis. By the comparison test of RT values among yellow pigment in croakers and reference pigments, such as zeaxanthine, ${\beta}-cryptoxanthine$, ${\beta}-carotene$, and astaxanthin, only ${\beta}-cryptoxanthine$ was detected in the white croaker, whereas such pigment of yellow croaker having RT value of 31.02 was not detected. Therefore, RT value was found to be applicable for detecting adulterated croaker.

• Journal of the korean academy of Pediatric Dentistry
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• v.30 no.4
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• pp.684-695
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• 2003

The aim of this study was to investigate the effect of composite resin components on proliferation and glucan synthesis by cariogenic bacteria, Streptococcus mutans and Streptococcus sobrinus. Light curing pit and fissure sealant was chosen for evluation. Specimens were eluted in deionized water for 10 minutes, 1, 12, and 24 hours. Extracts of specimens were diluted into 1/2, 1/4, and 1/8 with addition of BHI broth and BHI-YS. Bacteria were cultured in media included eluted components, and measured optical density($A_{600}$). The following results were obtained 1. 1/4 concentration of elutes for 10 minutes significantly inhibited the proliferation of S. mutans, whereas 1/2, 1/8 concentration of elutes stimulated it. Also, exacts, especially 1/2, 1/4 concentration, for 1 hours stimulated it. But exacts for 12, 24 hours had not effects on the proliferation of S. mutans. 2. 1/4 concentration of elutes for 10 minutes inhibited growth of S. sobrinus, whereas extracts for 1, 12, 24 hours had not effects on the proliferation of S. sobrinuss. 3. Extracts from composite resin stimulated total growth of S. mutans more than growth control group, where as inhibited it of S. sobrinus. 4. Extracts from composite resin, especially 1/4 concentration of it for 10 minutes increased the formation of water insoluble glucan of S. mutans. But elutes for 1, 12, 24 hours, and 1/8 concentration of it for 10 minutes inhibited it. 5. Except 1/4 concentration of elutes for 10 minutes, extracts decreased the formation of water insoluble glucan of S. sobrinus. 6. Total amount of formated glucan was 3-fold higher in S. mutans than in S. sobrinus.