• Korean Chemical Engineering Research
• /
• v.58 no.1
• /
• pp.29-35
• /
• 2020

In this study, the skin permeability was measured by adding cell penetrating peptides, arginine oligomers; (tetra-D-arginine (R4) and hexa-D-arginine (R6)) to little skin-permeable anti-wrinkle peptides (GHK, GHK-Cu, and Pal-GHK), and the results were analyzed by the following six cases. First, in cases where only anti-wrinkle peptides were contained, copper ions (Cu₂⁺) and palmitic acid enhanced the transdermal permeability. Second, when arginine oligomers (R4, R6) were added to GHK, arginine oligomers (R4, R6) increased percutaneous permeability, and R4 showed better percutaneous permeability. Third, the addition of R4 and R6 to GHK-Cu resulted in increased percutaneous transmittance, followed by R6 < R4 percutaneous transmittance. Fourth, when R4 and R6 were added to Pal-GHK, the percutaneous permeability increased with results in R6 < R4 order. Fifth, when R4 was added to GHK, GHK-Cu, and Pal-GHK, the transdermal permeability increased in the order of GHK+R4 < GHK-Cu+R4 < Pal-GHK+R4. Finally, the addition of R6 to GHK, GHK-Cu and Pal-GHK also resulted in increased percutaneous transmittance in the order of GHK+R4 < GHK-Cu+R4 < Pal-GHK+R4. This study provides optimal conditions for enhancing skin absorption of anti-wrinkle peptides GHK, GHK-Cu, and Pal-GHK, and propose a wide range of applications in anti-wrinkle functional cosmetics by suggesting ways to maximize their efficacy.

• Journal of the Korean Chemical Society
• /
• v.33 no.3
• /
• pp.273-280
• /
• 1989

The spectra of the $Co^{II}CyDTA$(CyDTA: cyclohexyldiaminetetraacetic acid) complex have been measured in aqueous solution of pH = 6-13.2. The red shift of the spectrum in the more basic solution was ascribed to the transformation of $CoCyDTA^{2-}$ into $CoCyDTA(OH)^{3-}$. The equilibrium constant, $K_{OH} = [CoCyDTA(OH)^{3-}]/[CoCyDTA^{2-}][OH^-]$ was $75M^{-1}$ at $40^{\circ}C$. The electron transfer reactions of $CoCyDTA^{2-}$ and $CoCyDTA(OH)^{3-}$ with $Fe(CN)_6^{3-}$ have been studied using spectrophotometric technique in the range of pH applied to the determination of equilibrium constant. The pseudo first-order rate constants observed ($k_{obs}$) were not changed upto pH = 10.8, but increased with increasing pH in the range of pH = $10.8{\sim}13.0$. The rate law reduced in the range of pH = 6-13 was $k_{obs} = (k_3[CoCyDTA^{2-}] + k_4[CoCyDTA(OH)^{3-}])/(1+K_1[CoCyDTA^{2-}])$. The rate constants of the reactions (3a) and (3b), $k_3$ and $k_4$ respectively have been determined to be 0.529 and $4.500M^{-1}sec^{-1}$ at $40^{\circ}C$. The activation entropies (147{\pm}1.1JK^{-1} mol^{-1}$ at pH = 10.8) and activation volumes $(6.25cm^3mol^{-1}, pH = 10.8)$ increased with increasing pH, while the activation enthalpy (12.44 ${\pm}$ 0.20 kcal/mole) was independent of pH. Using the pH effect on the rate constants, the activation entropies and the activation volumes, the mechanism of the electron transfer reaction for $Co^{II}-Fe^{III}$ system was discussed.

• Korean Journal of Agricultural Science
• /
• v.3 no.1
• /
• pp.67-75
• /
• 1976

This experiment was studies for grassland establishment on west coastal saline land in Korea from May 1975 to March 1976 and used seeds were introduced from Australia. The results of adaptability were summarized as follow. 1. The seeds germination percentage was not influence in 0.5% salt included, but delayed days in 1% salt included and decreased germination percentage. 2. Any experimental grasses species were not growth on the 0.5% salt included soil and also growth was much damaged on the 0.05% salt included soil. It was suggested that $Mg^+$, $K^+$ ions involved with $Na^+$ ion. 3. The yield of grasses were much decreased on 0.05% salt included soil which compared control group. The yield rate of decrease were 30% in kikuyu, 60% in strawberry clover, 63% in reed canarry and 89% in orchard grass. 4. For winter-hardness test, nearly all the species well overwintered but except kikyu. 5. One of salt tolerance native grass (Agrostis distans crieseb var coreensis, Hackel) was discovered in saline area, and it was growth from middle of May to Middle of September. Also it was known that the native grass was good feed stuff but it was not so long in growth life. 6. It was concluded that more experimental work must be carried out to select of salt tolerance grass for grassland establishment on saline by introduce some more species such like saltgrass, saltbush, shadsclae from foreign land.

• Korean Journal of Agricultural Science
• /
• v.7 no.2
• /
• pp.182-189
• /
• 1980

This experiment was carried out to study on methods of processing the fruit base which is to be used for preparing the fruit yoghurts. Common fruits were compared and peach was chosen among them for this purpose by determing the rate of decrease in hardness during the process of cooking. The maturity, temperature of cooking and methods of peeling were tested to maintain the desirable hardness during the process, and the effects of metallic ion addition on the hardness of the flesh were also studied. The results obtained were as follows. 1. The peaches were keeping the most stable texture during cooking, among common fruits, however the hardness of apples were decreased markedly. Rate of decreases in the flesh hardness were high during the initial stages of cooking then slowered in all fruits tested. 2. Flesh hardness of the peaches were largely affected by the temperature of cooking. And the texture of freeze-stored fruits was severly damaged during thawing, so that could be used only for the limited purposes such as for stirred-type yoghurt. 3. Divalent matallic ions, especially calcium ion, were effective for supporting the flesh hardness of peaches during cooking. 4. The optimal concentration of calcium chloride addition was 0.3%, and this resulted in its final concentration in the product under the legal dosage without any subsquent changes in colour and flavor. 5. The effects of calcium chloride addition were greater in the froms of dices than in those of slices, and in overmature fleshs than in immature ones. 6. Treatment of calcium chloride by soaking the slices or dices of lye-peeled peaches in 0.3% solution was found to be adaptable for the practical process.

• Journal of the Korean Chemical Society
• /
• v.45 no.3
• /
• pp.242-246
• /
• 2001

The quaternary thiophosphates, $A_2NiP_2S_6$ (A=Rb, Cs), have been synthesized with halide fluxes and structurally characterized by single-crystal X-ray diffraction technique. These compounds crystallize in the space group $C_{2h}^5-P2_1/n$ of the monoclinic system with two formula units in a cell of dimensions a=5.960(2), b=12.323(4), $c=7.491(3)\AA$, $\beta=97.05(3)^{\circ}$, and $V=546.0(3)\AA^3$ for Rb2NiP2S6 and a=5.957(4), b=12.696(7), $c=7.679(4)\AA$, $b=93.60(5)^{\circ}$, and $V=579.7(5)\AA^3$ for $Cs_2NiP_2S_6.$ These compounds are isostructural. The structure of $Cs_2NiP_2S_6$ is made up of one-dimensional $_\infty^1[NiP_2S_6^{2-}]$ chains along the a axis and these chains are isolated by $Cs^+$ ions. The Ni atom is octahedrally coordinated by six S atoms. These Ni$S_6$ octahedral units are linked by sharing three m-S atoms of the $[P_2S_6^{4-}]$ anions to form the infinite one-dimensional $_\infty^1[NiP_2S_6^{2-}]$ chain. For $Cs_2NiP_2S_6$, the magnetic susceptibility reveals an antiferromagnetic exchange interaction below 8K,which corresponds to the Neel temperature ($T_N$). Above $T_N$, this compound obeys Curie-Weiss law. The magnetic moment, C, and ${\theta}forCs_2NiP_2S_6$ are 2.77 B.M., 0.9593 K, and -19.02 K, respectively. The effective magnetic moment obtained from the magnetic data is agreed with the spin-only value of $Ni^{2+}d^8$(2.83 B.M.) system.

• Journal of the Korean Chemical Society
• /
• v.44 no.5
• /
• pp.403-409
• /
• 2000

The formation and dissociation rates of $Zn^{2+}$ Complexes with l,4,7,10-tetraaza-13,16-diox-acyclooctadecane-N,N',N",N'"-tetraacetic acid (1), 1,4,7,10-tetraaza-13,16- dioxacyclooctadecane-N,N',N",N'"-tetramethylacetic acid (2), and 1,4,7,10-tetraaza-13,16- dioxacyclooctadecane-N,N',N",N'"-tetrapropionic acid(3) have been measured by stopped-flow and conventional spectrophotometry. Observations were made at 25.0$\pm$0.1 $^{\circ}C$ and at an ionic strength of 0.10 M NaClO$_4$. The formation reactions of $Zn^{2+}$ ion with 1 and 2 took place by the rapid formation of an intermediate complex (ZnH$_3L^+$) in which the $Zn^{2+}$ ion is incompletely coor-dinated. This might then lead to be a final product in the rate-determining step.ln the pH range 4.76-5.76, the diprotonated (H2L2-) form is the kinetically active species despite of its low concentration. The stability con-stants (log$K_{(ZnH$_3$3$L^+$)}$) and specific water-assisted rate constants (koH) of intermediate complexes have been deter-mined from the kinetic data. The dissociation reactions of $Zn^{2+}$ complexes of 1,2, and 3 were investigated with $Cu^{2+}$ ions as a scavenger in acetate buffer. All complexes exhibit acid-independent and acid-catalyzed con-tributions. The effect of buffer and $Cu^{2+}$ concentration on the dissociation rate has also been investigated. The ligand effect on t dissociation rate of $Zn^{2+}$ complexes is discussed in terms of the side-pendant armsand the chelate ring sizes of the ligands.

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

• Journal of Life Science
• /
• v.27 no.4
• /
• pp.390-397
• /
• 2017

Iron (Fe) is an important micronutrient for the health and growth of plants. Iron is usually provided by fertilizers, and iron-chelate fertilizers are well absorbed by plants. This study presents the plant growth-promoting effects of a new functional iron fertilizer, Fe-chelating crab shell powder (FCSP), which is generated from the chelation of Fe ions with crab shell powder. Iron chelate was derived from spent pickling liquor, which is rich in reductive iron, iron(II) oxide. To analyze the effects of FCSP on plant growth, we treated lettuce with several concentrations of FCSP in both lab- and field-scale experiments. In the lab-scale test, the treatment of 50 ppm of FCSP highly promoted growth and resulted in increases in the size, weight, number and chlorophylls content of leaves of plants compared to the treatment of crab shell powder. Fifty ppm of FCSP also increased the size and weight of leaves up to 2 times compared to the application of chemical fertilizer and/or compost in field conditions. In addition, the FCSP treatment resulted in the highest ion uptake of Fe in lettuce leaves. Moreover, FCSP led to increases in the amounts of Fe, Ca, available phosphorus and organic matter in treated soil, indicating that soil quality was improved. Taken together, our results demonstrate that FCSP promotes lettuce growth via enhancement of Fe availability and improves soil quality. Therefore, FCSP can be utilized as a new functional iron fertilizer.

• Korean Journal of Food Science and Technology
• /
• v.29 no.5
• /
• pp.955-962
• /
• 1997

The food components of three kinds of edible ascidians being cultivated and caught in Tongyeong and Jisepo districts, Kyongnam of Korea were investigated. Wild Halocynthia roretzi (WM) and Pyura michaelseni (DM) were higher in contents of moisture and crude protein than cultured Halocynthia roretzi (CM). Total combined amino acid contents of CM, WM and DM muscles were 11,425.4 mg%, 11,595.4 mg% and 12,152.7 mg%, respectively, and major amino acids were Asp, Glu and Lys. The major fatty acids were 14:0, 16:0, 16:1n7, 18:1n7, 18:4n3, 20:5n3 and 22:6n3, and composition ratio of n3 polyunsaturated fatty acids of CM, WM and DM were 39.1%, 47.0% and 46.5%, respectively. In extracts components, total free amino acid contents of CM, WM and DM were 1,071.3 mg%, 1,278.7 mg% and 1,133.2 mg%, respectively, and the major amino acids were Tau, Glu, Pro, Asn, Gly, and Ala, while Arg was contained little quantities. As for nucleotides and related compounds, AMP was the principal component and IMP was detected though very small amounts in ascidian samples. Also contents of TMAO, total creatinine, betaine and peptide-N were $12.2{\sim}18.1\;mg%,\;15.5{\sim}19.6\;mg%,\;270.5{\sim}329.9\;mg%\;and\;62.0{\sim}111.0\;mg%,$ respectively. In inorganic ions of ascidian samples, the major components were $Na^+,\;K^+,\;Cl^-\;and\;PO^{3-}_4$.

• Journal of Korean Society for Atmospheric Environment
• /
• v.34 no.4
• /
• pp.567-587
• /
• 2018

A severe haze event occurred in October 2015 in Gwangju, Korea. In this study, the driving chemical species and the formation mechanisms of $PM_{2.5}$ pollution were investigated to better understand the haze event. Hourly concentrations of $PM_{2.5}$, organic and elemental carbon, water-soluble ions, and elemental constituents were measured at the air quality intensive monitoring station in Gwangju. The haze event occurred was attributed to a significant contribution (72.3%) of secondary inorganic species concentration to the $PM_{2.5}$, along with the contribution of organic aerosols that were strongly attributed to traffic emissions over the study site. MODIS images, weather charts, and air mass backward trajectories supported the significant impact of long-range transportation (LTP) of aerosol particles from northeastern China on haze formation over Gwangju in October 2015. The driving factor for the haze formation was stagnant atmospheric flows around the Korean peninsula, and high relative humidity (RH) promoted the haze formation at the site. Under the high RH conditions, $SO{_4}^{2-}$ and $NO_3{^-}$ were mainly produced through the heterogenous aqueous-phase reactions of $SO_2$ and $NO_2$, respectively. Moreover, hourly $O_3$ concentration during the study period was highly elevated, with hourly peaks ranging from 79 to 95ppb, suggesting that photochemical reaction was a possible formation process of secondary aerosols. Over the $PM_{2.5}$ pollution, behavior and formation of secondary ionic species varied with the difference in the impact of LTP. Prior to October 19 when the influence of LTP was low, increasing rate in $NO_3{^-}$ was greater than that in $NO_2$, but both $SO_2$ and $SO{_4}^{2-}$ had similar increasing rates. While, after October 20 when the impact of haze by LTP was significant, $SO{_4}^{2-}$ and $NO_3{^-}$ concentrations increased significantly more than their gaseous precursors, but with greater increasing rate of $NO_3{^-}$. These results suggest the enhanced secondary transformation of $SO_2$ and $NO_2$ during the haze event. Overall, the result from the study suggests that control of anthropogenic combustion sources including vehicle emissions is needed to reduce the high levels of nitrogen oxide and $NO_3{^-}$ and the high $PM_{2.5}$ pollution occurred over fall season in Gwangju.