• Journal of the Society of Cosmetic Scientists of Korea
• /
• v.45 no.2
• /
• pp.161-173
• /
• 2019

In this study, the antioxidative and inhibitory activity of tyrosinase and collagenase for the solvent extract and silica column fractions of Artocarpus nitidus were evaluated. The activities were quantified using the 4 parameter logistic. LC/MS analysis showed that the major component of the fractions was polyphenol and the total polyphenol content of the extract was $48.1{\pm}2.6mg\;GAE/g$. The radical scavenging activities ($SC_{50}$) for 1,1-diphenyl-2-picrylhydrazyl of the extract, fraction-1 and fraction-2 were 16.7, 42.0 and $10.1{\mu}g/mL$, respectively. The value for fraction-2 was the closest to ascorbic acid ($1.5{\mu}g/mL$). The tyrosinase inhibitory activity of the extracts and the fractions showed $IC_{50}$ of 64.9, 0.9 and $1.2{\mu}g/mL$, respectively, and overall activity was higher than that of kojic acid ($7.4{\mu}g/mL$) and arbutin ($119.0{\mu}g/mL$). In the experiment by zebrafish embryo, the whitening activity of fraction-2 (27.5%) was higher than that of kojic acid (18.6%), and there was no adverse effect up to $500{\mu}g/mL$ of fraction-2. For the collagenase inhibitory activity, the samples showed $IC_{50}$ of 139.8, 20.6, and $16.8{\mu}g/mL$, respectively, which were competitive to 1, 10-Phenanthroline ($55.4{\mu}g/mL$). The extract and fraction-2 showed $IC_{50}$ of 61.8 and $67.1{\mu}g/mL$ for elastase. These results suggest that A. nitidus extract can be used as a cosmetic material useful for antioxidant, whitening, and prevention of skin aging without adverse effects.

• The Korean Journal of Physiology
• /
• v.25 no.2
• /
• pp.125-131
• /
• 1991

Inactivation properties of Ca current in the unfertilized eggs of mouse were studied by using the whole cell voltage clamp technique and single microelectrode voltage clamp technique. Membrane potential was held at -80 mV and step depolarization was applied from -50 mV to 50 mV for $200{\sim}500\;ms$. Peak of inward Ca currents was $-2{\sim}-4\;nA$ at a membrane Potentials from -20 mV to 0 mV and outward currents were not observed within the membrane voltage range studied $(-50{\sim}50\;mV)$. Inward currents were fully inactivated within 200 ms after the onset of step depolarization. As the membrane became depolarized, time constant of inactivation (${\tau}$) was decreased but remained around $20{\sim}30\;ms$ beyond 10 mV. When $Ca^{2+}$ was used as a charge earlier, inactivation of inward $Ca^{2+}$ current also occured and time course of inactivation was similar to that of $Ca^{2+}$ currents as charge carrier. In the bathing solution containing high potassium $(131\;mM\;K^+)$, process of inactivation was not changed except a parallel decrease of value for the entire range of membrane potential. Steady-state inactivation of the $current(h_{\infty})$ obtained from the double pulse experiment showed the voltage-dependent change. These results suggested that inactivation of Ca currents in the unfertilized eggs of mouse was voltage-dependent.

• Korean Journal of Medicinal Crop Science
• /
• v.19 no.1
• /
• pp.38-46
• /
• 2011

In this study, we investigated maximum yield of radical scavenging activity (RSA) using each of various extraction solvents and procedure from noni friut (Morinda citrifolia). Noni fruits were either sun-dried (FS) or hot-air dried (FO) at $60^{\circ}C$ after steam blanching. For optimum aqueous extraction, noni fruits should be sun dried and autoclave extraction time should not be over 30 min to produce extraction with high RSA with low cost. In case of 50% ethanol extraction, reflux extracts of FS and FO resulted in $IC_{50}$ of 1.92 mg/mL and 3.06 mg/mL at 8 hr. When $IC_{50}$ values were lower than 5 mg/mL, coefficient of correlation was 0.71 indicating that 71% of the phenolic antioxidants in noni fruits were accounted for the activity by scavenging free DPPH. However, coefficient of correlation significantly decreased to 0.63 over $IC_{50}$ values of 5 mg/mL. Autoclave extraction contained chlorogenic acid of $14.69 \;{\mu}g/mL$ and scopoletin of $3.86 \;{\mu}g/mL$. Reflux extraction showed all three compounds, chlorogenic acid ($26.19 \;{\mu}g/mL$), quercetin ($19.59 \;{\mu}g/mL$), and scopoletin ($17.4 \;{\mu}g/mL$). Therefore, the result of this study indicated that the potential antioxidant activities and functional values were obtained significantly with reflux extraction from noni fruit.

• Journal of the Microelectronics and Packaging Society
• /
• v.13 no.4
• /
• pp.37-43
• /
• 2006

Surface roughness and hardness of the electroplated Sn were characterized with variations of electroplating current density and current mode. The Sn electroplated at $5{\sim}50mA/cm^{2}$ exhibited the surface roughness of $2.0{\sim}2.4{\mu}m$. The Sn electroplated with pulse current mode exhibited low surface roughness compared one processed with direct current mode. With surface annealing at $300^{\circ}C$ for 3 sec using halogen lamp, surface roughness of the Sn bump was substantially reduced to $1{\mu}m$. The Sn electroplated at $5{\sim}50mA/cm^{2}$ exhibited the hardness of 10 Hv. Low contact resistances of $33{\sim}17m{\Omega}$ were obtained for specimens flip-chip bonded with Sn bumps.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.19 no.6
• /
• pp.596-604
• /
• 1990

Polygalacturonase activity was not detected at turning stage but were 55.01 and 206.70 units/100g -fr. wt. in mature and soft persimmon, respectively. Polygalacturonase have two isoenzymes and its molecular weight was estimated to be 55,000 doltons by the method of gel filtration. Vmax and Km of polygalacturonase 1 were 0.195$\mu$ mole reducing-sugar/$m\ell$/30 min. and 3.50mg/$m\ell$, respectively. The optimum temperature and pH of the enzyme appeared to 4$0^{\circ}C$ and 3.5, respectively. Polygalacturonase I had Vmax of 0.110m mo1e reducing-sugar/$m\ell$/30min. and Km value of 2.50mg/$m\ell$, The optimum temperature and pH of polygalcturonase II appear 4$0^{\circ}C$ and 4.0, respectively. Polygalacturonase I was fairly stable at 6$0^{\circ}C$while polygalacturonase II appeared to be stable up to 4$0^{\circ}C$.

• Development and Reproduction
• /
• v.23 no.2
• /
• pp.111-117
• /
• 2019

This study focused on the association of prostaglandins and a progestin, $17{\alpha}$, $20{\beta}P$-dihydroxy-4-pregnen-3-one ($17{\alpha}20{\beta}P$) during the ovulation process in longchin goby, Chasmichthys dolichognathus. We performed several in vitro experiments using $850-920{\mu}m$ diameter oocytes which were at the migratory nucleus stage. With the $890-920{\mu}m$ diameter oocytes, no significant difference in ovulation was observed in any of the prostaglandins (PGE1, PGE2, and $PGF2{\alpha}$) treated groups although PGE2 and $PGF2{\alpha}$ at concentrations of 50 ng/mL increased ovulation slightly compared with controls; however, $17{\alpha}20{\beta}P$ production was stimulated with PGE1 alone at low concentrations (5 ng/mL). In $850{\mu}m$ diameter oocytes, $PGF2{\alpha}$ at concentrations of 50 and 500 ng/mL resulted in a significant increase in ovulation. $17{\alpha}20{\beta}P$ (50 ng/mL) alone had no observable effect on ovulation, but in the combined of $PGF2{\alpha}$ 50 or 500 ng/mL it caused the greatest effect on ovulation. The sensitivity of oocytes to the induction of ovulation varies between 850 and $890-920{\mu}m$, it appeared to vary depending on the migration status of nucleus. These results suggest that $PGF2{\alpha}$ (or combined of $17{\alpha}20{\beta}P$) was more potent in inducing ovulation of the longchin goby.

• Journal of Aquaculture
• /
• v.17 no.2
• /
• pp.122-127
• /
• 2004

On protein equivalence base, fishmeal (FM) was replaced by lysine cell mass (LCM) in selected different diets in Korean rockfish, Sebastes schlegeli (Hilgendorf) Eight experimental diets were formulated to contain 100% FM (LC $M_{0}$), 90% FM+10% LCM (LC $M_{10}$),80% FM+20% LCM (LC $M_{20}$), 70% FM+30% LCM (LC $M_{30}$), 60% FM+40% LCM (LC $M_{40}$ ), 70% FH+30% LCM+lysine (LC $M_{+Lys}$), 60% FM+40% LCM+lysine (LC $M_{40+Lys}$), and 50% FM+50% LCM+lysine (LC $M_{50+Lys}$). Experimental individuals of the fish (12.6 g) were randomly fed on one of the experimental diets. After 6 weeks of feeding trial, weight gain (WG) and feed efficiency (FE) of fish fed LC $M_{0}$ diet was significantly (P〈0.05) higher than those of fish fed LC $M_{20}$, LC $M_{30}$, LC $M_{40}$ , LC $M_{30+Lys}$, LC $M_{40+Lys}$, and LC $M_{50+Lys}$ diets, however, there was no significant difference in WG of fish fed LC $M_{0}$ and LC $M_{10}$ diets. Supplementation of lysine has no effect on WG. There was no significant difference in condition factor (CF) of fish fed LC $M_{0}$, LC $M_{10}$ and LC $M_{20}$ diets. Hemoglobin (Hb) of fish fed LC $M_{0}$, LC $M_{10}$, LC $M_{20}$, LC $M_{30}$, LC $M_{40}$ , LC $M_{30+Lys}$, and LC $M_{40+Lys}$, diets were not significantly different from each other. No significant differences were observed in hematocrit (PCV) and hepatosomatic index (HSI) among all dietary treatments. Apparent digestibility of dry matter (ADM) and protein (ADP) of diets significantly decreased with increase in dietary LCM level, though there was no difference in ADM and ADP between LC $M_{0}$ and LC $M_{10}$. These results indicate that LCM could replace up to 10% of fishmeal in Korean rockfish diets.ish diets.iets.ish diets.s.ish diets.

• Journal of the Korean Society of Fisheries and Ocean Technology
• /
• v.40 no.3
• /
• pp.176-181
• /
• 2004

In order to examine the mesh selectivity and optimum mesh size of trap nets for purple shell, Rapane venosa, the field experiments were carried out during Jun. 27 to 29, 2003 at the coastal area of Mal-Do, Kunsan, Jeonbuk province. The experimental fishing gears were used in two set of trap nets, which one set was consisted of 210 trap nets that were coverd with 35mm, 50mm and 65mm in mesh size. The analysis of mesh selectivity curve was done by Kitahara's method. The results obtained are summerized as follows : 1. The total number of catch by the experimental fishing of trap nets for purple shell was 1,682, and it was consisted of 1,268 purple shells (75.4%), 225 Glossaulax reiniana (13.4%), 113 green lings (6.7%) and 76 other fishes (4.5%). 2. The value of maximum 1/m on the mesh selectivity curve was estimated at 1.79. 3. The value of 1/m on the 50% selection range was estimated at 1.24${\sim}$2.72, and the selection width was 1.48.. 4. The optimum mesh size of trap nets for purple shell based on the catch prohibition shell height(50mm) was estimated 40.3mm, and the 50% selection range of shell height of purple shell was 50.0${\sim}$109.6mm.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.32 no.1
• /
• pp.115-118
• /
• 2003

This study was conducted to determine optimal extraction condition and free radical scavenging effect of ethanol extracts of Campell Early grape seeds and skins at different temperatures, and of organic solvent fractionated from ethanol extracts of grape seeds and skins. The free radical scavenging effect was tested using 1,1-diphenyl-2-picrylhydrazyl (DPPH) method and expressed as dose required for a 50% reduction of DPPH radical (RC$_{50}$). The extraction yields were increased with increasing the extraction temperature but it was not related with ethanol concentrations. The ethanol extract of grape seeds obtained at 5$0^{\circ}C$ showed the more stronger RC$_{50}$ (16.8 $\mu\textrm{g}$/mL) than those of both 3$0^{\circ}C$ and 78$^{\circ}C$. The ethylacetate fraction obtained from ethanol extract of grape seed showed the strongest RC$_{50}$ (15.4 $\mu\textrm{g}$/mL). Overall, both ethanol extracts and their fractions of grape seeds showed significantly stronger free radical scavenging effect than those of skin extracts.racts.

• Journal of Korean Society of Forest Science
• /
• v.85 no.1
• /
• pp.96-106
• /
• 1996

Red alder(Alnus rubra Bong.) seedlings inoculated with Frankia only or both Frankia and spores of Alpova diplophloeus(Zeller & Dodge) Trappe & Smith were grown in a greenhouse for ten weeks. The ten-week-old seedlings were fertilized with six nitrogen(N) and phosphorus(P) fertility regimes (no fertilization, 10mM $NH_4NO_3$, 50mM $NH_4NO_3$, 5mM $KH_2PO_4$, 10mM $NH_4NO_3+5mM$ $KH_2PO_4$, and 50mM $NH_4NO_3+5mM$ $KH_2PO_4$) three times a week for ten weeks. The higher N-fertilization significantly increased mycorrhiza formation by greenhouse contaminant mycorrhizal fungi, but decreased N-fixation and P concentration in nodule tissues. P-fertilization significantly increased nodule and shoot dry weight, and P concentration in plant tissues. When N was highly fertilized, however, the P-fertilization effect disappeared in nodule P concentration but doubled in leaf P concentration. A. diplophloeus inoculation significantly increased diameter growth and $CO_2$ exchange rate, but decreased leaf dry weight. Our results suggest that the higher N- or P-fertilization affect nitrogenase activity and mycorrhizal development but the effects are changed by their interactions.