• Environmental Analysis Health and Toxicology
• /
• 제5권1_2호
• /
• pp.37-44
• /
• 1990

Synthetic detergents and surfactants are in widespread usage as household and industrial detergents. Potential human toxic hazard arises following percutaneous absorption or oral ingestion of solution residues from kitchen and feeding utensils, fruits, and vegetables and contaminated water supplies. A toxicological investigations was performed with the synthetic detergents and surfactants [linear alkyl benzene sulfonate (LAS), ${\alpha}$-olefin sulfonate (AOS), sodium lauryl sulfonate (SLS), sodium lauryl ester sulfonate (SLES)］, In acute toxicity, agents were administered subcutaneously into ICR mice. In acute study, after lowering of spontaneous motility, respiratory failure, death appeared, vomitting was often associated with salivation and or retching. No sex difference was observed in LD$\sub$50/ of mice. In subacute toxicity, agents were administered orally into SD rats. Body weight increase was suppressed and there was no adverse effect on food and water consumption. The weight of organs were not changed by agents as compared with control group. No specific change was observed in biochemical and hematologicalor data.

• 한국응용과학기술학회지
• /
• 제8권1호
• /
• pp.55-58
• /
• 1991

Biosurfactant have a low toxicity, good biodegradable, various structure. It can be used for a broad range of purposes in a large variety of different applications. Sorbitol mono alkyl ester synthesized by the Porcine Pancreatic lipase catalyzes transesterification reaction between a sugar alcohol and plant oils. We are examined the surface tension, emusion stability and critical micelle concentration were evaluated. Consequently It has a good properties of biosurfactant.

• Journal of Microbiology and Biotechnology
• /
• 제25권11호
• /
• pp.1796-1800
• /
• 2015

Sporopollenin is a poorly characterized mixed aliphatic and aromatic polymer with ester and ether linkages. Recent studies have reported that α-pyrone polyketide compounds generated by Arabidopsis thaliana, polyketide synthase A (PKSA) and tetraketide α-pyrone reductase 1 (TKPR1), are previously unknown sporopollenin precursors. Here, the yeast Saccharomyces cerevisiae was introduced to test potential sporopollenin biosynthetic pathways in vivo. A PKSA/TKPR1 dual expressor was generated and various chain-length alkyl α-pyrones were identified by GC-MS. The growth rate of the strain containing PKSA/TKPR1 appeared normal. These results indicate that PKSA/TKPR1-expressing yeast would be a starting platform to investigate in vivo sporopollenin metabolism.

• 공업화학
• /
• 제23권2호
• /
• pp.232-240
• /
• 2012

바이오디젤(BD)은 식물성 오일 또는 동물성 지방과 같이 재생산 가능한 원료로부터 유래된 긴 사슬 지방산의 단일 알킬에스테르로, 디젤연료에 비해 낮은 온도에서 연료특성이 열악한 것으로 알려져 있다. 디젤연료의 경우, 많은 저온 유동성 향상제가 개발되어 있지만 바이오 디젤은 디젤연료와 주요 구성성분이 다르기 때문에 디젤연료용 저온 유동성 향상제를 바이오디젤에 사용 시 저온 유동성 향상에 한계가 따른다. 이에 본 연구는 동절기에 바이오디젤의 저온 특성을 향상시키고자 에스테르 반응으로 합성한 알킬 메타크릴레이트 단량체(Stearyl methacrylate, Lauryl methacrylate)와 무수말레인산을 이용하여 저온 유동성 향상제를 합성하였고, 알킬아민을 이용한 개환 반응을 실시하였다. 이렇게 합성된 저온 유동성 향상제를 $^1H-NMR$ 및 FT-IR을 통해 분석하였으며, GPC로 분자량을 측정한 후 SoybeanBD와 PalmBD에 1000~10000 ppm의 농도로 첨가하여 저온특성을 조사하였다. 그 결과 SoybeanBD에 LMA2SMA6MA2-C8A 공중합체 첨가 시 유동점이 $12.5\;^{\circ}C$ 강하됨을 확인하였다.

• 공업화학
• /
• 제3권4호
• /
• pp.694-700
• /
• 1992

Palladium 촉매에 의한 CO Insertion Heck reaction을 고분자 중합에 응용하여 가공성이 좋은 고강도 엔지니어링 플라스틱으로 응용 가능한 flexible spacer를 가진 aromatic polyamide와 Polyester를 합성할 수 있었다. 촉매로서 dichlorobis(triphenyl phosphine) palladium(II) $(PdCl_2(PPh_3)_2)$와 Palladium chloride($PdCl_2$)를 사용하였고, 이 중합 시스템은 똑같은 조건에서 polyamide와 polyester를 합성 할 수 있는 장점이 있으므로 그 중합체의 열적성질을 DSC, TGA 등으로 조사하였는데 곁사슬이 있지 않은 aromatic polyamide와 Polyester는 amide와 ester 결합의 차이에도 불구하고 전이온도등이 거의 같았다. Hexyl부터 hexadecyl까지 alkyl 곁사슬을 2,5 위치에 이중으로 가진 phenylene dibromide와 Phenylene diamine으로부터 중합체를 합성하였는데 치환기가 없는 경우에 비하여 전이온도가 감소하였고, alkyl side chain이 hexadecyl인 경우는 뚜렷한 융점을 확인할 수 있었다.

• 한국환경과학회지
• /
• 제17권5호
• /
• pp.509-516
• /
• 2008

New functional surfactant, N,N-dimethyl-N-dodecyl-N-(2-methyl benzimidazoyl) ammonium chloride(DDBAC) having benzimidazole(BI) functional group have been synthesized and the critical micellar concentration of DDBAC measured by surface tentiometry and electric conductivity method was $8.9{\times}10^{-4}M$. Micellar effects in DDBAC functional surfactant solution on the hydrolysis of p-nitrophenylacetate(p-NPA), p-nitro-phenylpropionate(p-NPP) and p-nitrophenylvalerate(p-NPV) were observed with change of various pH (Tris-buffer). The pseudo first rate constants of hydrolysis of p-NPA, p-NPP and p-NPV in optimum concentration of DDBAC solution increase to about 160, 280 and 600 times, respectively, as compared with those of aqueous solution at pH 8.00(Tris-buffer). It is considered that benzimidazole functional moiety accelerates the reaction rates of hydrolysis because they act as nucleophile or general base. In optimum concentration of DDBAC solution, the rate constants of hydrolysis of p-NPP and p-NPV increase to about 1.5 and 3.0 times, respectively, as compared with that of p-NPA. It means that the more the carbon numbers of alkyl group of substrates, the larger the binding constants between DDBAC micelle and substrates are. To know the hydrolysis mechanism of p-NPCE(p-NPA, p-NPP and p-NPV), the deuterium kinetic isotope effects were measured in $D_2O$ solutions. Consequently the pseudo first order rate constant ratios in $H_2O$ and $D_2O$ solution, $k_{H_2O}/k_{D_2O}$, were about $2.8{\sim}3.0$ range. It means that the mechanism of hydrolysis were proceeded by nucleophile and general base attack in approximately same value.

• 한국토양환경학회지
• /
• 제3권2호
• /
• pp.115-125
• /
• 1998

오염된 토양 중 phenanthrene의 분해에 미치는 비이온계 계면활성제와 생물계면활성제의 영향을 살펴보았다. 비이온계 합성 계면활성제로 polyoxyethylene oreyl esterC$^{17}$ H$^{33}$ COO($C_2$$H_4$O)nH) 와 생물계면활성제인 sophorolipid를 적용하였다. 계면활성제의 농도, 수분함량, 접종균 처리 방법 및 종류, pH, 온도, 부가영양분 등의 변수들이 phenanthrene의 생분해에 미치는 영향을 비교실험 하였다. 계면활성제 농도가 CMC이하의 경우 계면활성제는 phenanthrene의 생분해성을 촉진하였으나, CMC 값 이상의 영역에서는 계면활성제가 미생물의 phenanthrene분해작용을 저해하였다. 30%의 수분함량과 pH 7, $30^{\circ}C$에서, 부가영양분으로 glucose를 10g/L수준으로 첨가하였을 때 좋은 분해도를 나타내었다. 충진제로 짚이 첨가되는 경우 토양 : 짚의 중량비가 5:2이고, 수분함량이 50%인 경우 phenanthrene의 분해가 촉진되었다.

• 청정기술
• /
• 제13권2호
• /
• pp.104-108
• /
• 2007

바이오디젤은 식물성 또는 동물성 유지를 알콜과 화학적으로 반응하여 얻어진 지방산 알킬에스터로서 친환경적인 대체에너지로 주목받고 있다. 본 연구에서 폐식용유와 유채유에 대한 전처리 공정에 고체 산(acid)이온 교환수지를 도입하여 자유지방산을 제거함으로써 바이오디젤로의 전환율을 높이고자 하였다. 이온교환수지를 이용한 전처리를 통해 자유지방산의 90%이상을 제거할 수 있었으며 젖은 상태의 수지보다 건조 상태의 수지의 자유지방산 제거효율이 높은 것으로 나타났다. 전이에스테르화를 통해 최대 98%의 수율로 지방산 메틸에스터를 얻을 수 있었으며 본 연구 결과는 자유지방산의 제거가 필요한 바이오디젤 원료유의 전처리에 효과적으로 적용될 수 있다.

• 한국응용과학기술학회지
• /
• 제15권2호
• /
• pp.83-92
• /
• 1998

${\alpha}-sulfonated$ fatty acid polyethylene glycol esters with polyethylene oxide(addition, 3, 5, 10mol) were synthesized through esterification of ${\alpha}-sulfonated$ fatty acid methyl esters with alkyl chain length $C_{12}{\sim}C_{18}$. Their compounds were separated with column chromatography, and confirmed by TLC. Quantitative analysis of all the sulfonates were performed according to JIS K-3362 method, and ethylene oxide unit number were determined by ISO 2270 method. Structural properties of ${\alpha}-sulfonated$ fatty acid methyl esters and their derivatives were also identified from IR, and $^1H$ NMR spectra.

• Bulletin of the Korean Chemical Society
• /
• 제32권7호
• /
• pp.2187-2192
• /
• 2011

Hydrogen peroxide plays a key role as a second messenger in the normal cellular signaling but its overproduction has been implicated in various life-threatening diseases. Peroxalate chemiluminescence is the light emission from a three component reaction between peroxalate, hydrogen peroxide and fluorophores. It has proven great potential as a methodology to detect hydrogen peroxide in physiological environments because of its excellent sensitivity and specificity to hydrogen peroxide. We developed chemiluminescent micelles composed of amphiphilic polymers, peroxalate and fluorescent dyes to detect hydrogen peroxide at physiological concentrations. In this work, we studied the relationship between the chemiluminescence reactivity and stability of peroxalate by varying the substitutes on the aryl rings of peroxalate. Alkyl substitutes on the aryl ring of peroxalate increased the stability against water hydrolysis, but diminished the reactivity to hydrogen peroxide. Chemiluminescent micelles encapsulating diphenyl peroxalate showed significantly higher chemiluminescence intensity than the counterpart encapsulating dimethylphenyl or dipropylphenyl peroxalate. Diphenyl peroxalate-encapsulated micelles could detect hydrogen peroxide generated from macrophage cells stimulated by lipopolysaccharide (LPS) and image hydrogen peroxide generated during LPS-induced inflammatory responses in a mouse.