• 한국임상수의학회지
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• 제15권1호
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• pp.75-78
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• 1998

This study was performed to estimate the clinical signs and changes of biochemical parameters in rats with hepatic injury induced by the administration of 2, 2'-azobis(2- amidinopropane)dihydrochloride (AAPH) . Minor behavioral change, brittleness of skin hair and decreased volume of water and feed intake were observed in ra% 2 hours after AAPH administration compared to control group. Concentration of serum albumin showed lower than that of control group. However, concentration of total bilirubin has shown higher than that of control group. As time goes on, . serum LDH activity increased significantly compared to control group, but senun CPK activity did not change compared to control group. Passive hemanglutination of $\alpha $-fetoprotein was negative in all the treaDent groups and control group.

• 한국임상수의학회지
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• 제15권1호
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• pp.79-82
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• 1998

This study was performed to determine the changes of serum enzyme activities in rats with hepatic injury induced by the administration of AAPH. Minor behavioral change, brittleness of skin hair and decreased water and fled intake were observed in rats administered intraperitoneally with AAPH. Serum AST and ALT activities pre-treatment were $65{\pm} 13.8 and 32{\pm}$ 12.6 IU/L, respectively and increased sharply from 2 hours of administration and reached $1248{\pm} 77.6 and 946{\pm}$ 45.6 IU/L, respectively at 48 hours of administration. Serum ALP and $\gamma -GTP activities pretreatment were 221 {\pm} 75.6 and 2.2{\pm}$ 0.35 IU/L respectively and increased sharply from 8 hours of administration and reached $767{\pm} 44.9 IU/L and 8.0{\pm} 1.23 IU/L,$ respectively at 48 hours of administration.

• 공업화학
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• 제21권3호
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• pp.353-355
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• 2010

양이온성의 2,2'-azobis(2-methylpropionamidine) (AIBA) 개시제를 이용한 methylmethacrylate (MMA)의 무유화제 에멀전 중합을 통해 polymethylmethacrylate (PMMA) 입자를 합성하였다. 스퇴버 방법을 이용하여 양이온성의 PMMA 입자 표면에 실리카를 코팅하였다. 음전하의 실리카 전구체는 양이온성의 PMMA 입자 표면과의 정전기적 인력에 의해 코팅된다. 실리카 코팅 과정 중에 PMMA 입자가 용해되어 후처리 없이 실리카 중공체를 얻을 수 있었다.

• BMB Reports
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• 제37권4호
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• pp.416-421
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• 2004

The antioxidant activities of NADH and of its analogue, 1,4-dihydro-2,6-dimethyl-3,5-dicarbethoxy-pyridine ($PyH_2$), were evaluated in vitro. NADH was found to be oxidized by the peroxyl radical derived from 2,2-azobis-(2-amidinopropane) dihydrochloride (AAPH) decomposition, in a pH-dependent manner. Both NADH and $PyH_2$ inhibited the peroxidation of egg yolk lecithin (EYL) liposomes, although $PyH_2$ was more effective than NADH when 2,2'-azobis-4-methoxy-2,4-dimethyl-valeronitrile (methoxy-AMVN) was employed to induce EYL liposome peroxidation. The antioxidant activities of NADH and $PyH_2$ were also evaluated by measuring their influences on 1,3-diphenylisobenzofuran (DPBF) fluorescence decay in the presence of peroxyl radicals. NADH and $PyH_2$ were much more effective at inhibiting DPBF quenching in Triton X-100 micelles than in liposomes. These results indicate that NADH can inhibit lipid peroxidation despite being hydrophilic. Nevertheless, membrane penetration is an important factor and limits its antioxidant activity.

• Food Science and Biotechnology
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• 제18권4호
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• pp.904-909
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• 2009

The beneficial effects derived from consuming natural antioxidants may not depend on the action of an individual antioxidant, but rather on the concerted action of several antioxidants naturally present. The aim of this study was to determine the concentrations and combinations of antioxidants that can produce synergistic effects (SyEs). Quantification of the lipoperoxyl radical scavenging capacity of antioxidants was carried out in a homogeneous model system where the free radicals were produced by the oxidation of methyl linoleate, initiated by the 2,2'-azobis (2,4-dimethylvaleronitrile). The greatest SyE (2.21, p<0.05) was seen in mixtures of all 4 antioxidants when used with concentrations of 15 ${\mu}M$ lycopene, 2.5 ${\mu}M$ vitamin E, 0.16 ${\mu}M$ vitamin C, and 10 ${\mu}M$ ${\beta}-carotene$. Doubling the vitamin E concentration from 2.5 to 5.0 ${\mu}M$ in the mixture with all 4 antioxidant reduced the SyE to 1.69 (p<0.05). Other combinations produced synergistic effects that ranged from 1.28 to 1.41.

• Food Science and Biotechnology
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• 제18권5호
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• pp.1253-1257
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• 2009

Exo-polysaccharide isolated from the culture of Grifola frondosa was modified by sodium periodate ($NaIO_4$) and sodium chlorite ($NaClO_2$) to delete polysaccharide part and phenolic compound, respectively, and was investigated what effect has each part of exo-polysaccharide against 2,2'-azobis(2-amidinopropane) dihydrochloride (AAPH)-induced oxidative stress in porcine kidney epithelial cells (LLC-PK1). Oxidative stress on LLC-PK1 cell was measured by cell viability, lipid peroxidation, superoxide dismutase (SOD), and glutathione peroxidase (GSH-px) activity. Exposure of LLC-PK1 cells to 1 mM AAPH for 24 hr resulted in significant decrease in cell viability, SOD, and GSH-px action, and significant increase in lipid peroxidation. The treatment of exo-polysaccharide and $NaIO_4$ modified sample protected LLC-PK1 cells from AAPH-induced cell damage such as cell viability, lipid peroxidation, SOD, and GSH-px activity in a dose dependant manner (10, 100, and $500{\mu}g/mL$). However, the treatment of $NaClO_2$ modified sample did not affect for cell viability, lipid peroxidation, SOD, and GSH-px activity. The antioxidant activity of exo-polysaccharide was significantly decreased on AAPH-induced LLC-PK1 cell system when phenolic compound was deleted. The antioxidant activity was significantly correlated with the content of phenolic compound of exo-polysaccharide.

• Fibers and Polymers
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• 제2권2호
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• pp.108-115
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• 2001

Vinyl acetate was polymerized in ultraviolet-ray initiated bulk system at low temperatures using 2,2-azobis(2,4-dimethylvaleronitrile) (ADMVN) or 2,2-azobis(isobutyronitrile) (AIBN) as the photoinitiator, respectively. High molecular weight (HMW) poly(vinyl alcohol) (PVA) having number-average degree of polymerization ($P_n$) of 3,900-7,800 and syndiotactic diad (S-diad) content of 52.5-54.0% could be prepared by complete saponification of synthesized linear poly(vinyl acetate) (PVAc) having $P_n$ 5,900-9,400 obtained at conversion of below 30%. $P_n$ of PVA using ADMVN was larger than that of PVA using AIBN. On the other hand, conversion of the former was smaller than that of the latter, and it was found that the initiation rate of the ADMVN was lower than that of AIBN. This could be explained by a fact that the rate of photolysis of AIBN is faster than that of ADMVN due to the higher quantum yield or dissociation rate constant of AIBN than that of ADMVN. The $P_n$, syndiotacticity, and whiteness of PVA from PVAc polymerized at lower temperatures were superior to those of PVA from PVAc polymerized at higher temperatures.

• Preventive Nutrition and Food Science
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• 제14권1호
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• pp.37-42
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• 2009

The protective activity of seolitae chungkukjang added with green tea against oxidative stress was investigated under the cellular systems using LLC-$PK_1$ cells. The treatment of 2,2'-azobis(2-aminopropane) dihydrochloride (AAPH) showed increase in lipid peroxidation, and decrease in endogenous antioxidant enzymes activity and cell viability. However, the methanol extract of seolitae chungkukjang inhibited lipid peroxidation by 58.3%, and increased cell viability up to more than 60%. In addition, it enhanced superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities. Seolitae chungkukjang improved oxidative stress-induced cellular injury through the radical scavenging activities. In particular, the addition of green tea in seolitae chungkukjang showed stronger effect against oxidative stress induced by AAPH. The more addition of green tea resulted in the greater antioxidative effect through elevation in activities of SOD and GSH-Px, and inhibition of lipid peroxidation, eventually leading to increase in cell viability. Theses results suggested that seolitae chungkukjang added with green tea have protective effects from cellular oxidative damage and could be considered as an application for the development of chungkukjang with functionality.

• 대한화학회지
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• 제24권5호
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• pp.398-403
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• 1980

4,4'-azobis-[4-cyano valeric acid]를 개시제로 하여 라디칼 중합에 의해 carboxyl-terminated polybutadiene을 제조하고, 개시제의 농도가 중합체의 물성에 미치는 영향을 조사하였다. 부타디엔 농도를 일정하게 유지하고, 개시제 농도를 변화시켜 중합한 결과, 개시제농도가 증가함에 따라 카르복실기 함량이 감소하고 중합수율은 개시제농도의 1/2 제곱에 정비례하였으며, 관능도가 2.0을넘어 일반적인 라디칼 중합의 경향과 일치하였다.

• 한국축산식품학회:학술대회논문집
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• 한국축산식품학회 1998년도 정기총회 및 제21차 춘계학술발표회
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• pp.167-167
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• 1998