• 한국식품과학회지
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• 제47권5호
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• pp.561-566
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• 2015

350 ppm 농도로 물/카놀라 기름 에멀션에 첨가된 달걀 노른자 위 레시틴은 에멀션 기름의 철 이온에 의한 자동산화와 클로로필에 의한 감광산화에 유의한 영향을 나타내지 않았다. 에멀션의 산화 중 달걀 노른자위 레시틴으로부터 유래한 인지방질은 분해되었으며 감광산화에 비해 자동산화에서 분해 속도가 높았다. 그러나 PC와 PE 사이의 분해 속도는 두 종류의 산화에서 모두 유의한 차이를 보이지 않았다(p>0.05).

• Food Science and Biotechnology
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• 제18권2호
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• pp.526-532
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• 2009

Quenching mechanisms and kinetics of $\alpha$-, $\beta$-, $\gamma$-, and $\delta$-tocopherol in photosensitized oxidation of lard were studied. Lard at 0.03, 0.07, 0.11, and 0.3 M in methylene chloride containing $4.4{\times}10^{-6}\;M$ chlorophyll and 0, 0.1, 0.3, and 0.6 mM $\alpha$-, $\beta$-, $\gamma$-, and $\delta$-tocopherol were stored under light for 4 hr, respectively. Oxidation was determined by headspace oxygen and peroxide value. Tocopherols prevented the photosensitized oxidation of lard (p<0.05). Steady state kinetic study showed that $\alpha$-, $\beta$-, $\gamma$-, and $\delta$-tocopherol prevented the photosensitized oxidation of lard by quenching singlet oxygen. Singlet oxygen quenching rates of $\alpha$-, $\beta$-, $\gamma$-, and $\delta$-tocopherol by headspace oxygen depletion were 1.86, 2.39, 2.47, and $2.11{\times}10^7/M/sec$, respectively. The quenching rates of $\alpha$-, $\beta$-, $\gamma$-, and $\delta$-tocopherol by peroxide value were 1.42, 1.11, 0.97, and $0.42{\times}10^7/M/sec$, respectively. The quenching rates of tocopherols were slightly different depending on the measurements of oxidation.

• Journal of Photoscience
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• 제10권1호
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• pp.175-180
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• 2003

Zeolite, Nafion membranes and vesicles were used as microreactors to control the pathway of photosensitized oxidation of alkenes and remarkable selectivity was achieved.

• 한국식품과학회지
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• 제46권2호
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• pp.127-134
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• 2014

참치유 보강 에멀젼에 첨가된 참기름은 클로로필의 존재 하에 $25^{\circ}C$, 1,700 lux의 빛에서 에멀젼 유지의 광산화를 유의하게 감소시켰다. 또한 참기름의 첨가는 에멀젼의 광산화 중 산성 조건에서 클로로필로부터 전환된 페오피틴의 분해속도를 낮추어 일중항산소 생성이 많았을 가능성에도 불구하고 일중항산소와 라디칼 소거능을 가진 인지방질, 토코페롤, 폴리페놀 화합물을 제공함으로써 참치유 보강 에멀젼 유지의 산화안정성을 개선하였으며 인지방질, 토코페롤에 비해 폴리페놀 화합물이 더 큰 영향을 주었다. 리그난 화합물은 에멀젼의 광산화 중 변화를 보이지 않아 물리적 기전에 의한 일중항산소 소거 작용을 암시하였다.

• Bulletin of the Korean Chemical Society
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• 제7권1호
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• pp.78-81
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• 1986

The photosensitized lysis of egg lecithin lipid membranes (liposomes) have been performed to UV-B light (270-320 nm) by L-tryptophan(L-Trp) and its peptide such as N-acetylphenylalanyl-L-tryptophan(NAPT) incorporated in the liposomes(ca. 0.1% by weight) or in the external buffer (0.1-0.3 mM). Requirement of oxygenation suggests that the lysis of liposomes is caused by the photosensitized oxidation of lipids. There was significant protection against lysis photosensitized by Trp in the external buffer by low concentration of ferricyanide (0.8 mM), but there was no effect on the lytic efficiency by $N_3^-$ which is singlet oxygen($^1O_2$) quencher, indicative of an electron transfer mechanism involved in the photosensitization. The small change of the lytic efficiency with increasing pH from 4 to 9 was interpreted by large target theory and subsequently indicates that superoxide($O_2^-$) may be an active intermediate for the oxidation. The efficiency of photosensitization of Trp was higher than that of NAPT under the same experimental condition. The weak lytic efficiency of liposomes photosensitized by NAPT was enhanced by incorporating NAPT in liposomes, but it was again quenched by ${\beta}$-carotene incorporated in the bilayer of liposomes. These results indicate that a portion of liposome lysis may be due to $^1O_2$ formation from the excited NAPT.

• 한국광과학회:학술대회논문집
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• 한국광과학회 2005년도 제12회 학술대회 논문초록
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• pp.18-18
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• 2005

• Rapid Communication in Photoscience
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• 제4권2호
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• pp.41-44
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• 2015

Biomolecular photo-damaging activity of a water-soluble cationic porphyrin was examined using human serum albumin (HSA), a water-soluble protein as a target biomolecule model by a fluorometry. Dichlorophosphorus(V) tetraphenylporphyrin ($Cl_2P(V)TPP$), was synthesized and used as a photosensitizer. This porphyrin could bind to HSA and cause the photosensitized oxidation of HSA through the singlet oxygen generation and the oxidative photo-induced electron transfer (ET). Near infrared emission spectroscopy demonstrated the photosensitized singlet oxygen generation by this porphyrin. Decrement of the fluorescence lifetime of $Cl_2P(V)TPP$ by HSA supported the ET mechanism. Furthermore, the estimated Gibb's energy indicated that the ET mechanism is possible in the terms of energy. Because oxygen concentration in cancer cell is relatively low, ET mechanism is considered to be advantageous for photosensitizer of photodynamic therapy.

• Journal of Photoscience
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• 제6권3호
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• pp.85-90
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• 1999

Supramolecular photochemistry is concerned with systems where non-covalent interactions become significant or dominate in determining the chemistry of guest/host systems. The photocycloaddition of diaryl compounds and the photosensitized oxidation of alkenes included in zeolites, low-density polyethylene films and Nafion membranes is the subject of this report.

• 한국식품영양학회지
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• 제37권1호
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• pp.48-56
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• 2024

Effects of glutamic acid (Glu) and monosodium glutamate (MSG) on oxidative stability of oil-in-water (O/W) emulsions with different emulsifier charges during riboflavin (RF) photosensitization were evaluated by analyzing headspace oxygen content and conjugated dienes. Cetyltrimethylammonium bromide (CTAB), Tween 20, and sodium dodecyl sulfate (SDS) were used as cationic, neutral, and anionic emulsifiers, respectively. Glu acted as an antioxidant in CTAB- and Tween-20-stabilized O/W emulsions during RF sensitization, whereas Glu acted as prooxidants in SDS-stabilized O/W emulsions in the dark. However, adding MSG did not have a constant impact on the degree of oxidation in O/W emulsions irrespective of the emulsifier charge. In RF-photosensitized O/W emulsions, the emulsifier charge had a greater influence on antioxidant properties of Glu than on those of MSG.

• 한국식품과학회지
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• 제37권5호
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• pp.717-722
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• 2005

불포화지방산의 대표적인 물질 중 하나인 올레산에 백열등 조사와 리보플라빈에 의해 생성되는 휘발성 물질들을 분리 및 동정하였다. 리보플라빈 첨가 시료에서는 리보플라빈 무첨가 시료 보다 39시간 동안 270%의 휘발성 물질이 더 생성되었으며 수용액형태가 비수용액 시료보다 휘발성 물질이 유의적으로 많이 발생하였다(p<0.05). 2-Heptenal은 리보플라빈 첨가 시료에서만 검출되었으며 heptane, octane, heptanal, octanal, nonanal, 2-nonenal은 리보플라빈 광산화 시료에서 대조구에 비해 39시간 동안 각각 8.71, 5.88, 2.58, 2.16, 2.80, 5.84배 이상 증가하였다. 2-Nonenal과 heptanal과 같이 기존 삼중항산소 산화기작에 의해 설명될 수 없었던 휘발성물질의 생성 기작을 일중항산소에 의한 산화 기작을 통해 제시하였다. 본 연구는 올레산 첨가 식품의 광산화에 의한 휘발성분 profile 규명 자료로 활용될 수 있을 것이다.