• Bulletin of the Korean Chemical Society
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• 제5권4호
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• pp.149-153
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• 1984

Reactions of $MoOCl_5^{2-}$ with ${\alpha}_2-[P_2W_{17}O_{61}]^{10-}$ have been studied spectrophotometrically and several complexes have been identified. The transient species initially formed is probably $[Mo_2O_4(P_2W_{17}O_{6l})_2]^{18-}$. At $pH {\le} 3$the visible spectrum changes gradually, indicating formation of a transient isomer of $[P-2Mo^VW_{17}O_{62}]^{7-}$, which again transforms into the stable isomer. The transient isomer absorbs light much more strongly than the stable isomer in the visible range. At $pH > 3 [P_2W^VW_{16}O_{61}]^{11-}$ is formed probably via the transient isomer of $[P_2Mo^VW_{17}O_{61}]^{7-}$.

• Bulletin of the Korean Chemical Society
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• 제5권2호
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• pp.65-68
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• 1984

Reactions of $MoOCl_5^{2-}$ with $[PW_{11}O_{39}]^{7-}\;and\;[SiW_{11}O_{39}]^{8-}$ have been studied spectrophotometrically and several transient complexes have been discovered. Transient species initially formed are probably $[Mo_2O_4(PW_{11}O_{39})_2]^{12-}\;and\;[Mo_2O_4(SiW_{11}O_{39})_2]^{14-}$. Spectra change gradually, indicating formation of transient isomers of $[PMoW_{11}O_{40}]^{4-}\;and\;[SiMoW_{11}O_{40}]^{5-}$, which again transform into the stable isomers. The transient isomers absorb light much more strongly than the stable isomers in the visible range.

• 한국토양비료학회지
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• 제49권5호
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• pp.589-597
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• 2016

There are a number of industrial complexes which could be a source of heavy metal (loid)s contamination of arable soil in Gyeongnam province of South Korea. Heavy metal (loid)s accumulation of plant is more related to the concentration of plant available heavy metal (loid)s in arable soil than that of total heavy metal (loid)s. The objectives of this study were 1) to examine heavy metal concentrations in soils located near industrial complexes in Gyeongnam province and 2) to determine the relationship between concentration of plant available heavy metal (loid)s and chemical properties of soil. Soil samples were collected from 85 sites of arable lands nearby 7 industrial complexes in Gyeongnam province. Total heavy metal (loid)s concentration, available heavy metal (loid)s concentration, and chemical properties of collected soils were measured. The mean concentrations of arsenic (As), cadmium (Cd), copper (Cu), lead (Pb), and zinc (Zn) in the soils were $5.8mg\;kg^{-1}$, $1.3mg\;kg^{-1}$, $0.03mg\;kg^{-1}$, $51.5mg\;kg^{-1}$, and $68.7mg\;kg^{-1}$, respectively. Total concentration of Cd and Zn in arable soil located near ${\nabla}{\nabla}$ industrial complex exceeded the warning criteria ($4mg\;kg^{-1}$ and $300mg\;kg^{-1}$ for Cd and Zn, respectively) as described by in the soil environmental conservation Act of Korea. The concentration of plant available heavy metal (loid)s was negatively related to the soil pH and available Pb and Zn concentrations had relatively high correlation coefficient when compared with other heavy metal (loid)s. The concentration of plant available Pb and Zn was negatively related to that of organic matter (OM). Based on the above results, it might be a good soil management to control pH and OM concentration with soil amendments such as lime and compost to reduce phytoavailability of heavy metal (loid)s in arable soil located near industrial complex.

• 한국미생물·생명공학회지
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• 제12권4호
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• pp.277-283
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• 1984

제방 효모로 부터 분리 정제한 adenylate kinase 는 한개의 기질에 의해 또 하나의 기질 결합을ADP생성 반응에서는 4배, AMP와 Mg·ATP 생성에서는 2배 촉진되었다. 기질 특이성에 있어서는 nucleotide monophosphale일 경우 dAMP만이 활성을 보여주었으며 nucleotide triphosphate일 경우 ATP이외 UTP, ITP, GTP의 순위로 활성이 높았다. AMP와 Mg·ATP가 기질일 경우 과잉의 AMP는 pH 7.2와 pH8.0에서는 Mg·ATP에 경쟁적으로 저해하였으며 pH가 높을수록 그 Ki정수는 낮았다. Phosphoenolpyruvate는 AMP에 대해 경쟁적 Mg·ATP에 대해서는 비 경쟁적 저해제 이었으며 Adenosine pentaphosphoadenosine은 모든 기질에 대해 경쟁적 저해제로 작용하였다. 제빵 효모로부터의 adenylate kinase는 아미노산 조성에 있어서 동물의 Mitochondria형에 가까우며 Ito등의 결과와 일치하지 않았다. 상기와 같은 효소학적 성질을 종합 고찰한 결과 효모 adenylate kinase는 동물의 Mitochondria형 효소로 분류할 수 있으며 효모 adenylate kinase에 있어 연구자 상호간의 차이점은 사용한 균주의 차이에 기인하는 것으로 생각된다.

• Bulletin of the Korean Chemical Society
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• 제31권5호
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• pp.1314-1318
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• 2010

The $[Ru(tpy)_2]Cl_2$ (tpy:2,2':6',2"-terpyridine) complex was synthesized and its structure was confirmed by $^1H$-NMR and elemental analysis. Its binding mode toward DNA was compared with the well-known $[Ru(bpy)_3]Cl_2$ (bpy:2,2-bipyridyl), using isotropic absorption, linear dichroism(LD) spectroscopy, and an energy minimization study. Compared to $[Ru(bpy)_3]^{2+}$, the $[Ru(tpy)_2]^{2+}$ complex exhibited very little change in its absorption pattern, especially in the MLCT band, upon binding to DNA. Furthermore, upon DNA binding, both Ru(II) complexes induced a decrease in the LD magnitude in the DNA absorption region. The $[Ru(tpy)_2]^{2+}$ complex produced a strong positive LD signal in the ligand absorption region, which is in contrast with the $[Ru(bpy)_3]^{2+}$ complex. Observed spectral properties led to the conclusion that the interaction between the ligands and DNA bases is negligible for the $[Ru(tpy)_2]^{2+}$ complex, although it formed an adduct with DNA. This conclusion implies that both complexes bind to the surface of DNA, most likely to negatively charged phosphate groups via a simple electrostatic interaction, thereby orienting to exhibit the LD signal. The energy minimization calculation also supported this conclusion.

• 대한화학회지
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• 제22권5호
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• pp.320-325
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• 1978

우라늄의 수용액 및 산성용액으로부터 추출제 DEPA 및 DPPA로 우라늄을 추출할 때의 메카니즘을 밝히기 위하여 추출 중에 형성되는 우라늄 착물을 분리, 유리한 후 적외선 스펙트럼, 핵자기공명 스펙트럼, 화확분석 및 분자량 측정결과 등을 이용하여 규명하였다. 우라늄은 추출과정에서 유기인산 에스테르인 추출제 DEPA 및 DPPA의 산성 수소와 이온 교환에의하여 킬레이트형의 우라늄 착물을 형성하며 DEPA의 경우 분자량이 약 $2.1{\times}10^4$인 고분자물질임을 알았다. 또한 이러한 유리된 우라늄의 착물은 추출중에 형성되는 착물과 동일함을 밝혔으며 추출제 DEPA의 경우 우라늄의 추출 분배계수는 수용액의 경우 제일 크고 산성 수용액인 경우 $H_3PO_4의 순으로 증가함을 알았다.

• IMMUNE NETWORK
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• 제4권3호
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• pp.131-142
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• 2004

In recent years, adjuvants have received much attention because of the development of purified subunit and synthetic vaccines which are poor immunogens and require adjuvants to evoke the immune response. Therefore, immunologic adjuvants have been developed and testing for most of this century. During the last years much progress has been made on development, isolation and chemical synthesis of alternative adjuvants such as derivatives of muramyl dipeptide, monophosphoryl lipid A, liposomes, QS-21, MF-59 and immunostimulating complexes (ISCOMS). Biodegradable polymer microspheres are being evaluated for targeting antigens on mucosal surfaces and for controlled release of vaccines with an aim to reduce the number of doses required for primary immunization. The most common adjuvants for human use today are aluminum hydroxide and aluminum phosphate. Calcium phosphate and oil emulsions have been also used in human vaccination. The biggest issue with the use of adjuvants for human vaccines is the toxicity and adverse side effects of most of the adjuvant formulations. Other problems with the development of adjuvants include restricted adjuvanticity of certain formulations to a few antigens, use of aluminum adjuvants as reference adjuvant preparations under suboptimal conditions, non-availability of reliable animal models, use of non-standard assays and biological differences between animal models and humans leading to the failure of promising formulations to show adjuvanticity in clinical trials. The availability of hundreds of different adjuvants has prompted a need for identifying rational standards for selection of adjuvant formulations based on safety and sound immunological principles for human vaccines. The aim of the present review is to put the recent findings into a broader perspective to facilitate the application of these adjuvants in general and experimental vaccinology.

• Applied Biological Chemistry
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• 제2권
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• pp.45-52
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• 1961

The decomposition of malathion in dust for mulations prepared from four Korean tales as carriers during storage period has been studied. Amberlite CG-120, a cation exchange resin . which has higher cation exchange capacity than tales, was also used as a carrier in hope of finding out the effect of nagative charge upon the decomposition of malathion. Besides the original talc powders obtained directly from the mines, the hydrogen ion saturated forms were also used as carriers for comparisonal study. The saturated ions for the resin were hydrogen, sodium and magnesium. As the physical properties of the tales, colloid content, water adsorption capacity, PH, specific surface, phosphate fixing capacity and exchangeable canons were determined, and these properties were correlated with the amount of the decomposition. Following results were obtained from the experiment. 1. The malathion in the talc in dust was found to decompose around 10-15% ofthe total withina month. About 50% of the decom position that took place after a month was found to occur within a week. 2. The resin which has higher cation exchange capacity than the tales was highly effective in the decomposition of malathion compared with the tales. 3. In every case the saturation of the exchange complexes with hydrogen ion greatly accelerated the decomposition of malathion. 4. The most highly correlated physical properties with the decomposition were colloid content and specific surface of the tales. 5. The water adsorption and phosphate fixing capacities of the tales were found not to correlate with the amount of malathion decomposed. From the experimental results it was concluded that the active negative spots on the colloidal tales or the resin attract the electropositive phosphorus atom in a malathion molecule thereby inducing the decomposition easier. The presence of hydrogen ion nearby might cause a catalytic effect in the decomposition of malathion.

• KSBB Journal
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• 제21권2호
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• pp.151-156
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• 2006

본 연구에서는 용매증발법을 이용하여 대표적 생리활성 물질인 Vitamin-C의 불안정성을 극복하기 위하여 HP-${\beta}$-CD와의 포접복합체를 제조하고 수용액상에서의 안정성을 분석하였다. Vitamin-C와 HP-${\beta}$-CD 간의 몰비를 변화시켜 제조한 포접복합체의 안정성 시험 결과 포접 몰비는 1:1로 추정되며, 포접복합체 제조에 사용된 용매의 유전상수가 커질수록 Vitamin-C의 안정성이 향상되는 것을 확인할 수 있었다. 3차 증류수를 용매로 하여 제조된 포접복합체의 경우 순수한 Vitamin-C보다 Vitamin-C의 겉보기 1차 분해속도 상수 값이 감소하는 것을 확인하였는데 이는 결과적으로 Vitamin-C의 안정성이 향상되었음을 의미한다. 따라서 HP-${\beta}$-CD와의 포접복합체 형성은 Vitamin-C의 안정성을 향상시켜 생체이용률을 향상시킬 수 있음을 확인하였으며 불안정한 여러 생리활성물질에 적용할 수 있을 것으로 기대된다.

• BMB Reports
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• 제36권6호
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• pp.597-602
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• 2003

Acid phosphatases (APases) play a role in the release of phosphate in organic complexes in soil. We investigated tissue- and isoform-specific responses of APases to phosphorus (P) deficiency in three rice genotypes; Dasan-byeo, Sobi-byeo, and Palawan. The levels of shoot APase activity per protein were similar in the three genotypes. They significantly decreased with P deprivation that was longer than seven days. Root APase activity per protein was two- to three-fold higher in Dasan than in Sobi and Palawan. In all genotypes the APase activity increased in P-deficient plants, but the increase was higher in Sobi and Palawan. After 21 days of P deprivation, secreted APase activity increased more than eight-fold in Dasan and two-fold in Sobi and Palawan. Isoform profiles of shoot and root APases were most diverse in Dasan. The activities of the major isoforms in P-deficient shoots decreased in all three genotypes. Depending on the genotypes, further increases in constitutive isoforms and new induction of one to four isoforms occurred in P-deficient roots. The results indicate that tissue and genotype differences in the response of APase to P deficiency are primarily facilitated by the different responses of the isoforms.