• 한국식생활문화학회지
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• 제23권1호
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• pp.26-32
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• 2008

: In this experiment, three samples of oils were used. These oils were hydrated soybean oil, pure soybean oil and regular soybean oil. Oil was used after heating at $235-240^{\circ}C$ every four hours term and total heating hours was 16 hours. The physio-chemical analysis and sensory evaluation were performed on these oils. The hydrated soybean oil showed lower acid, peroxide and carbonyl value than the other two oils (p<0.05 or p<0.001). The other two oils were more affected in rancidity than the hydrated soybean oil. In color test, whereas L value lowed during the heating time, a and b value increased during the heating time. The tendency of high L value and low b value in a long-time heating was more apparant on the pure soybean oil and the regular soybean oil than on the hydrated soybean oil (p<0.05). In sensory evaluation, color and rancidity order increased during the heating time. The hydrated soybean oil showed color and rancidity order than the other two oils. In overall quality test, the pure and regular soybean oil that had been used for 12 and 16 hour were not preferable. The hydrated soybean oil that had been used for 16 hour were not preferable. In sensory evaluation, the hydrated soybean oil, the pure and regular soybean oil did not show a apparent difference, although the hydrated soybean oil had a little better scores on the overall quality.

• Journal of Photoscience
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• 제4권2호
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• pp.61-67
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• 1997

The model based on the idea that the p$_y$-orbital of the carbonyl oxygen is responsible to receiving hydrogen was devised for simulation of intramolecular hydrogen transfer. A Monte Carlo method was applied to free rotation of a molecular chain performed by changing the dihedral angles, and a "hit" was defined as the case when the migrating hydrogen comes within the region defined as the p$_y$-orbital and satisfies all the geometrical requirements for abstraction. A set of parameters was employed for defining the region and the requirements; $\tau$ was defined as the angle formed between O...H vector and its projection on the mean plane of the carbonyl group (- 43$\circ$ < $\tau$ < + 43$\circ$), $\Delta$ as the C=O...H angle (90 -15$\circ$ < $\Delta$ < 90 + 15$\circ$), $\theta$ as the O...H - C angle ( 180 - 80$\circ$< 0 < 180 + 80$\circ$), d as the distance from the center of the lobe of the p$_y$-orbital to hydrogen (0 < d < 1.04 ${\AA}$). The minimum value for the distance between carbonyl oxygen (O$_1$) and the migrating hydrogen (H$_i$) and for that between non-bonded atoms except the pair of O$_1$ and H$_i$ were assumed to be 0.52 ${\AA}$ and 1.54 ${\AA}$, respectively. The apphcation of this model to intramolecular $\beta$-, $\gamma$-, $\delta$-, $\epsilon$-, and $\zeta$-hydrogen abstraction in ketones and $\eta$- and $\theta$- proton transfer in oxoesters gave good results reflecting their photochemical behavior. The model was also used for prediction of photoreactivities of 2-(N,N-dibenzylamino)ethyl 2-, 3- and 4-benzoylbenzoate (1a - c). (1a - c).

• Food Science and Biotechnology
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• 제17권6호
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• pp.1341-1344
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• 2008

The present study was conducted to investigate the effects of flowers ethanol extract of Elsholtzia splendens (ESE) on the antioxidant defence system in mice with 7,12-dimethylbenz(a)anthracene (DMBA)-induced oxidative stress. The ESE was pre-administered orally to 2 groups of mice at 10 and 50mg/kg body weight (BW) for 5 weeks. Subsequently, mice with pretreatment of ESE received DMBA intragastrically at a dose of 34 mg/kg BW twice a week for 2 weeks. In DMBA alone group, biomarkers of oxidative stress (TBARS value, carbonyl content, and serum 8-OH-dG) were significantly increased. Also, the antioxidant enzymes were down-regulated. ESE significantly restored the TBARS value and carbonyl content at both doses, while a decrease in the elevated serum 8-OH-dG content was observed only at the higher dose. The DMBA-induced decreases in catalase and superoxide dismutase (SOD) activities were restored to nearly control levels by ESE. Glutathione peroxidase (GSH-px) and glutathione reductase (GR) activities, as well as the reduced glutathione (GSH)/oxidized GSH (GSSG) ratio, were significantly affected by ESE at the higher dose. These results suggest that ESE possesses antioxidant activity, which plays a protective role against DMBA-induced oxidative stress.

• 한국식품영양과학회지
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• 제27권4호
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• pp.603-608
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• 1998

Lipid oxidation in ascidian was studied when fresh, deshelled and sliced meats were fermented for 50 days at 5$\pm$2$^{\circ}C$ with 8%(w/w) salt and 0.1% papain. Antioxidative effects of butylated hydroxytoluene(BHT) and carotenoid extracts from ascidian tunic on lipid oxidation and oxidationrelated discoloration of ascidian meat during fermentation were investigated. Changes in peroxide value, carbonyl value, thiobarbituric acid value, fatty acids composition, the loss of total carotenoid and sensory evaluation were determined to assess the rancidity. Peroxide and carbonyl values in BHT and carotenoid extract treatments increased less than those of the control during fermentation. TBA value increased until 30 days, hereafter tended to decrease a little in the control during fermentation. TBA value increased until 30 days, hereafter tended to decrease a little in the control but it increased slowly until 40 days in cases of 0.02% BHT or 0.02% BHT with 0.05% carotenoid added. Fatty acids of fresh ascidian composed of polyenoic acid, saturated acid and monoenoic acid of 51.5%, 28.1% and 20.7%, respectively. Saturated fatty acids(C16:0, C14:0, C18:0) and monoenoic acids(C18:1, C16:1) increased while polyenoic acids(C20:5, C22:6) decreased during fermentation. Carotenoid was markedly degraded and discolored in the control during fermentation. But 0.02% BHT and 0.05% carotenoid treatments had bright color like fresh meat during 40 days. The results of sensory evaluation during the fermentation also convinced the retard of discoloration by the addition of BHT and carotenoid.

• 한국축산식품학회지
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• 제38권6호
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• pp.1203-1215
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• 2018

The antioxidant effects of Allium hookeri root (AHR) were investigated by evaluating lipid and protein oxidation in meatballs during refrigerated storage at $4{\pm}1^{\circ}C$. AHR was mixed at concentrations of 0.5% (w/w, T2) and 1% (w/w, T3) with minced longissimus dorsi muscle. Meatballs containing AHR (T2 and T3) were compared to those containing 0.05% (w/w) ascorbic acid (T1) as a reference and without antioxidant as a control. The 2-thiobarbituric acid reactive substances (TBARS) value, disulfide bond formation, carbonyl contents, and volatile basic nitrogen (VBN) value of T2 were lower than those of the control during storage (p<0.05). The pH values of T2 and T3 were higher than that of the control (p<0.05). Texture profile analysis of T2 revealed a lower value compared to the control (p<0.05). Therefore, the VBN value, TBARS value, disulfide bond formation, and carbonyl content in meatball containing AHR were lower than those of the control meatball. These results indicate that AHR improves the quality of meat products and functions as an antioxidant.

• Bulletin of the Korean Chemical Society
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• 제33권2호
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• pp.499-504
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• 2012

The specific rates of sovolysis of 4-methylthiophene-2-carbonyl chloride (1) have been determined in 26 pure and binary solvents at $25.0^{\circ}C$. Product selectivities are reported for solvolyses of 1 in aqueous ethanol and methanol binary mixtures. Comparison of the specific rates of solvolyses of 1 with those for p-methoxybenzoyl chloride (2) in terms of linear free energy relationships (LFER) are helpful in mechanistic considerations, as is also treatment in terms of the extended Grunwald-Winstein equation. It is proposed that the solvolyses of 1 in binary aqueous solvent mixtures proceed through an SN1 and/or ionization (I) pathway rather than through an associative $S_N2$ and/or addition-elimination (A-E) pathway.

• 한국식품조리과학회지
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• 제8권2호
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• pp.95-105
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• 1992

This study was carried on the Seasoning Oil production by Autoclaving Method in order to research a developed method. The Raw, Extract states of seasoning vegetables-Garlic, Onion and Ginger were added 40, 60% (w/w) of total amounts to corn salad oil. All samples treated with various conditions were determined physicochemical characteristics by Acid value, Peroxide value, Iodine value, Refractive Index, and Volatile Carbonyl Compound Content during incubating $(40{\pm}2^{\circ}C)$ and heating $(185{\pm}2^{\circ}C)$. The results were obtained as follws; 1. During incubation at $40{\pm}2^{\circ}C$, the order of antioxidative effects among seasoning vegetables was Ginger>Garlic>BHA>Onion and Extract state were more effective man Raw state. also the antioxidative effects of the seasoning vegetables were increased proportionally with the concentration in the Seasoning Oils. 2. In the case of heat treatment $(185{\pm}2^{\circ}C)$, AV, POV, IV and RI of each Seasoning Oil were changed very sharply. The antioxidative effect and Carbonyl Compound Content according to heat treatment differed from the type and concentration of seasoning vegetables in oil. Ginger had the most excellent antioxidative effect among seasoning vegetables, and m any case, the adding states of seasoning vegetables into oils were more effective in Extract man Raw states. 3. According to those results, each Seasoning Oil made from Garlic, Onion, Ginger was shown to have antioxidative properties specially in Ginger-Extract-Seasoning Oil. also the Autoclaving Method was thought to be rational method in preparation of Seasoning Oil.

• 한국수산과학회지
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• 제20권2호
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• pp.146-151
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• 1987

정어리유의 산화 안정성과 지질추출시에 첨가한 BHA에 의한 저장중의 산화방지효과를 정토하고 산화로 인한 지방산 조성의 면화를 조사한 결과를 요약하면 다음과 같다. 1. BHA는 유리 지방산의 생성을 현저히 억제하는 효과가 있었다. 2. BHA는 과산화물 생성을 억제하였으며 특히 카르보닐 화합들의 생성을 아주 강하게 억제하였다. 즉 BHA는 과산화을 분해를 억제하는 작용이 있었다. 3. 정어리유는$C_{20:5}$와 $C_{22:6}$의 함량이 $23\%$ 이상으로서 매우 높았다. 4. 산화에 의한 지방산의 감소는 polyene 산에서 급격하였으며 특히 $C_{20:5}$와 $C_{22:6}$산이 급격히 감소하였다. BHA 첨가는 $C_{22:5}$와 $C_{22:6}$산의 산화를 크게 억제 할수 있었다.

• 한국식품과학회지
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• 제33권1호
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• pp.1-6
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• 2001

수용성 단백질을 첨가한 유화물을 형광 조명하에서 $5^{\circ}C$에서 8일간 저장하였을 때 POV(Peroxide value) 값의 변화를 측정한 결과 저장 초기에 유의적인 증가를 나타냈고 TBA(Thiobarbituric acid) 값의 변화에서도 저장 4일까지 상당량의 카르보닐 화합물이 발생하는 것으로 나타나서 일반적인 지방의 자동산화와는 다른 양상을 보였고 대두유 같은 유지에서 저장 초기에 나타나는 변향의 발생과 비슷한 결과를 나타냈다. 이러한 원인으로는 육색소인 myoglobin에 의한 산화로 사료되며 superoxide anion보다는 일중항 산소에 의한 산화일 가능성이 높은 것으로 사료된다. 빛을 차단하였을 때에도 전체적인 양상을 비슷했지만 산화생성물의 생성량이 빛을 쪼였을 때보다 약간 적었고 일중항 산소의 효과도 두드러지지 않았으며 유화물 제조과정 중에 생성된 일중항 산소가 저장 초기의 변향에 관여하였을 것으로 추정된다. 수용성 단백질을 첨가하지 않은 경우에는 과산화물의 생성량이 지속적인 증가를 나타내서 수용성 단백질 처리구와 차이를 보였는데 과산화물의 분해속도가 수용성 단백질 처리구에 비해 작은 것으로 사료되며 특히 저장 4일 이후에 카르보닐 화합물의 생성속도가 줄어드는 것으로 나타났다. 저장 중에 일중항 산소의 발생 가능성이 있는 것으로 나타났으나 대두유의 탈색과정에서 잔존하였을 식물성 감광체가 원인일 것으로 추정된다. 빛을 차단하였을 때에는 저장 초기의 산화생성물 발생량이 빛을 쪼였을 때보다 미미했고 소거제 처리에 대한 효과도 드러나지 않아서 지질의 산화에 대한 빛의 촉진효과를 나타내는 결과라고 사료된다.

• 한국식품영양과학회지
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• 제23권6호
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• pp.899-907
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• 1994

Accumulation of peroxidized lipid, fed or injected in the body of rats was investigated and the effect of peroxidized lipid on the antioxidative system was studied also. Three groups each having six of Sprague-dawley rats were raised for 8 weeks. the peroxide value(POV) of diet fed to the control and the peroxidized group was 5.47 and 22.14meq/kg , respectively. Injected group was given the control diet and peroxidized linoleic acid(POV 31.81meq/kg) was injected into the peritoneal area three times a week. The POV, MDA, and protein carbonyl values of the peroxidized and the injected group (experimental groups) were significantly higher (p<0.05) than those of the control group. Cu, Zn-SOD and M-SOD activity of the experimentla groups increased 1.6 times that of control group at 4 th week. and decreased by 60% of their activityafter 8 weeks of feeding (p<0.05) . Catalase activity, glutathione and Vt, E contents of the experimental groups were significantly lower (p<0.05) than those of the control group during 8 weeks. The accumulation of peroxidcized lipid in liver were ovserved both in the fed or the injected group. The increased of enzyme activity of the experimental group during 4 weeks suggests ianadaptation of antioxidative system to get rid of the peroxidized lipid. Decrease of enzyme activity and glutathione observed as the peroxidized lipid lipid accumulation proceeded further, however, seems to indicate the oxdiative damage of enzyme and protein . Determination of the protein carbonyl content may be used as a method for measuring the oxidative damaging effect of peroxidized lipid.