• Journal of Nutrition and Health
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• 제30권4호
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• pp.442-450
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• 1997

Conjugated dienoic derivatives of linoleic acid(CLA) are a mixture of positional and geometric isomers of linoleic acid(LA). We previously found that CLA changes the fatty acid profile in chicken eggs and serum by decreasing monounsaturated fatty acids. Studies were conducted to explore the effects of CLA on fatty acid composition. Rabbits were fed a semisynthetic diet with or without CLA(0.5g CLA/rabbit/day) for 22 weeks. Compared to the control, rabbits fed CLA had significantly lower monounsaturated fatty acid levels(palmitoleic acid Cl6 : 1 by 50% and oleic acid Cl8 : 1, by 20%) in plasma lipids. We found similar differences in fatty acid composition in the liver and the aorta. The inhibitory effect of CLA on $\Delta$9 desaturation was confirmed in a human hepatoma cell line, Hep G2. CLA significantly decreased $\Delta$9 desaturation in 4-5 hours as shown by an increase in the ratio of Cl6 : 0 to C 16 1, This is apparently due to a decrease in $\Delta$9 desaturase(stearoyl-CoA desaturase, SCD) activity ; it was decreased more than 50%. These results, along with our previous findings, indicate that CLA is an inhibitor of $\Delta$9 desaturase in the liver.

• Preventive Nutrition and Food Science
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• 제8권3호
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• pp.253-259
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• 2003

Conjugated linoleic acid (CLA) is a class of positional, geometric conjugated dienoic isomers of linoleic acid (LA). CLA activates the immune system, protects against tumorigenesis, and reduces the incidence of atherosclerosis. Trans-10, cis-12 CLA has specific effects on lipid metabolism, it has been shown to reduce body fat gain and regulates some adipocyte secreted proteins in vivo and in vitro. Here we report that a CLA mixture affects cytokine secretion from rat primary adipocytes. Rat primary adipocytes were treated with 1 mM, 100 $\mu$M, 1 $\mu$M or 100 nM CLA mixture doses; and leptin, tumor necrosis factor alpha (TNF a ), interleukin-6 (IL-6) and glycerol levels in the medium were measured. Leptin secretion was lower, TNF $\alpha$ secretion higher and IL-6 secretion did not change in response to the CLA mixture. Leptin and TNF $\alpha$ secretions did not change with CLA mixture treatment in a dose-dependent manner. In addition, the CLA mixture did not appear to enhance lipolysis in rat primary adipocytes. In conclusion, our study demonstrates that the decrease in leptin and increase in TNF $\alpha$ secretion in adipocytes treated with CLA mixture may be due to the apoptotic effect and to a reduction in peroxisome proliferator-activated receptor gamma (PPAR ${\gamma}$ ) ligands.

• 한국축산식품학회지
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• 제36권2호
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• pp.170-177
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• 2016

Conjugated linoleic acid (CLA) is a group of positional and geometric isomers of conjugated dienoic derivatives of linoleic acid. CLA has been reported to be able to reduce body fat. In this study, we investigated the antidiabetic effect of fermented milk (FM) containing CLA on type II diabetes db/db mice. Mice were treated with 0.2% low FM, 0.6% high FM, or Glimepiride (GLM) for 6 wk. Our results revealed that the body weight and the levels of fasting blood glucose, serum insulin, and leptin were significantly decreased in FM fed mice compared to db/db mice. Oral glucose tolerance and insulin tolerance were significantly ameliorated in FM fed mice compared to db/db mice. Consistent with these results, the concentrations of serum total cholesterol, triglycerides, and LDL cholesterol were also significantly decreased in FM fed mice compared to db/db mice. However, the concentration of HDL cholesterol was significantly higher in FM fed mice compared to db/db mice. These results were similar to those of GLM, a commercial anti-diabetic drug. Therefore, our results suggest that FM has anti-diabetic effect as a functional food to treat type II diabetes mellitus.

• 한국식품영양과학회지
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• 제30권3호
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• pp.377-381
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• 2001

Chlorophyll a and b, pheophytin a and b and $\beta$-carotene, crude chlorophylls and carotenoids (CCC) extracts of mustard leaf kimchi were isolated by DEAE-sepharose CL-6B and Sepharose CL-6B colume and TLC. The effects of chlorophyll a and b, pheophytin a and b and $\beta$-carotene on linoleic acid autoxidation were examined by the determination of peroxide value and conjugated dienoic acid content. Among them, chlorophyll a showed greater antioxidative activity than others, followed by chlorophyll b, pheophytin a, pheophytin b and $\beta$-carotene. Degradation of pheophytin b was observed to be slower than others and $\beta$-carotene showed highest degradation level during the autoxidation reaction of linoleic acid.

• 한국식품영양학회지
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• 제22권4호
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• pp.662-668
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• 2009

소목으로부터 분리한 brazilin을 potato chip 제조시 사용하는 튀김유에 첨가하여 항산화 활성 정도를 시험하였다. 이때 현재 사용중인 항산화제도 동일 조건에서 시험하였다. 저장 30일 후 potato chip에서 추출한 유지의 과산화물가는 대조구(control), BHA(50 ppm)-BHT(50 ppm), $\delta$-tocopherol(100 ppm) 및 brazilin(100 ppm)이 각각 134 meg/kg oil, 84.06 meg/kg oil, 117.10 meg/kg oil 및 68.56 meg/kg oil을 나타내었다. 각 처리구는 대조구에 비하여 BHA(50 ppm)-BHT(50 ppm)가 1.6배, $\delta$-tocopherol(100 ppm)이 1.14배, brazilin(100 ppm)이 1.97배의 항산화 효과를 나타내었다. 위 결과에서 brazilin(100 ppm)의 경우, BHA(50 ppm)-BHT(50 ppm)보다도 과산화 물가가 낮아 과산화물 생성 억제력이 효과적임을 알 수 있다. 또한 유도기간연장 효과는 Rancimat을 이용한 고온가열시험($180^{\circ}$, 100 ppm)에서 대조구에 비하여 BHA(50 ppm)-BHT(50 ppm)가 1.4배, brazilin (100 ppm)이 1.53배로 brazilin이 상업용 항산화제보다 보다 항산화 효과가 높게 나타났다. 또한 brazilin(100 ppm)은 palmitic acid($C_{16:0}$)/linoleic acid($C_{18:2}$) 값의 감소를 억제하는 능력과 conjugated dienoic acid 함량의 증가 억제력이 상업용 항산화제보다 우수하였다.

• 한국식품조리과학회지
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• 제28권4호
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• pp.443-450
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• 2012

This study was investigated the effect of an oil-water fryer on quality properties of deep frying oil used for chicken. The acid and conjugated dienoic acid values of frying oil using an oil-water fryer were lower than those using a deep fat fryer, whereas the iodine value of frying oil using an oil-water fryer was higher than that using a deep fat fryer. The peroxide values of frying oil did not increase with frying number. Frying oil with an oil-water fryer had lower palmitic acid, stearic acid and oleic acid, and higher linoleic and linolenic acid contents than those with a deep fat fryer. The contents of trans-fatty acids in frying oil using a deep fat fryer and oil-water fryer after frying 110 chickens were 0.75% and 0.47%, respectively. The benzopyrene contents of frying oil using a deep fat fryer and an oil-water fryer after frying 110 chickens were 2.20 and $1.61{\mu}g/kg$, respectively.

• 한국식품영양과학회지
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• 제31권6호
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• pp.1126-1133
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• 2002

CLA 이성체 mixture와 trans-10,cis-12 CLA는 살아있는 TSU-Prl 세포 수를 감소시키는 반면 LA와 cis-9,trans-11 CLA는 세포 수에 아무런 효과가 없었다. 세포 수를 감소시키는 CLA 이성체 mixture와 tran-10, cis-12 CLA는 apoptotic cell death를 유도하는 것을 관찰하였고, 특히 trans-10,cis-12 CLA는 Bcl-2/Bax 비율을 감소시켰다. Trans-10,cis-12 CLA에 의해 Bax와 Bcl-2 mRNA의 수준이 변하지 않았으므로 이 지방산에 의한 Bcl-2의 변화는 mRNA 전사 후에 일어나는 단계에서 일어난다고 결론지을 수 있다. 이로써 CLA에 의한 세포증식 억제는 부분적으로 TSU-Prl 세포의 apoptosis를 유도함으로서 이루어지는 것이라 할 수 있다.

• Food Quality and Culture
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• 제1권1호
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• pp.6-12
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• 2007

In this study, we examined the effects of egg yolk powder added to flour dough on the lipid oxidation of fried products during storage. The flour dough containing the egg yolk powder (0, 5, and 10%) was fried in sunflower oil at $180^{\circ}C$ for 90 sec. The fried products were then stored at $60^{\circ}C$ for 9 days in the dark. The lipid oxidation of the fried products was evaluated by fatty acid composition, peroxide values (POV), conjugated dienoic acid (CDA) contents, and thiobarbituric acid (TBA) values. The color and phospholipids (PL) contents of the fried products were also determined by colorimetry and high performance liquid chromatography, respectively. The addition of egg yolk powder to the dough decreased the POV, CDA contents, and TBA values of the fried products during storage. Although POV, CDA contents, and TBA values significantly increased in the products without egg yolk powder during storage, little change was observed in the products with egg yolk powder. The PL contents remained relatively constant in the flied products added with egg yolk powder during storage. The lightness and greenness of the fried products decreased, and the yellowness increased, as the storage time increased. The results clearly indicate that the addition of egg yolk powder to the dough improved the lipid oxidative stability of the fried products during storage in the dark, and the PL in the egg yolk might have contributed to the improvements in lipid oxidative stability.

• 한국식품조리과학회지
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• 제23권2호통권98호
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• pp.180-186
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• 2007

In this study, we examined the effects of different water activities (Aw: 0.3, 0.5, and 0.8) on the lipid composition and oxidation of wheat flour after 28 days of storage in the dark at $60^{\circ}$C. The lipid content of the flour was 2.7%, and had decreased significantly (p<0.05) at the end of the storage period. Decrease in monoacylglycerol and increase in free fatty acids were observed, however, phosphatidic acid, phosphatidylglycerol, and phosphatidylinositiol were not detected after storage. Phosphatidylehtanolamine was more stable than phosphatidylcholine during the dark storage of flour. The flour lipids consisted of palmitic (18%), stearic (1%), oleic (14%), linoleic (63%), and linolenic (4%) acids, and the relative content of linolenic acid decreased after 28 days of storage. The conjugated dienoic acid content of the flour lipid had increased due to lipid oxidation during dark storage. Hydrolysis of neutral lipids and glycolipids, and lipid oxidation, were higher in the flour stored at Aw 0.8 than in the flour stored at Aw 0.3 or 0.5.

• Applied Biological Chemistry
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• 제37권3호
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• pp.168-174
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• 1994

여과 및 원심 분리가 $70^{\circ}C$ 저장 중 참기름의 산화 안정성에 미치는 영향을 headspace gas chromatography법에 의한 헥산알 생성과 기름의 과산화물가 및 공액 이중 결합 측정에 의해 살펴보았다. 볶은 참깨로부터 얻은 조참기름은 유리지방산, 공액 이중결합과 금속(철, 구리, 마그네슘 및 아연)을 더욱 많이 함유한 반면 수분과 ${\gamma}-tochopherol$은 여과 참기름 또는 원심분리 참기름에 더 많이 함유되었다. 여과 참기름은 세 종류의 기름 중 가장 큰 L과 b값의 우수한 색도에도 불구하고 조참기름보다 많은 과산화물을 함유하였다. 모든 참기름이 $70^{\circ}C$ 저장 중 색차가 증가하는 경향을 보였으며 여과 참기름에서의 리놀렌산 감소 경향을 제외하고는 비교적 일정한 지방산 조성을 보였다. 산화 안정성에 있어서 원심분리 참기름과 조참기름은 a=1%에서 유의적인 차이를 보이지 않았으며 여과 참기름은 이들보다 산화안정성이 떨어졌다. 원심분리 참기름이 산화안정성과 유지의 색도 측면에서 가장 좋은 것으로 나타났다.