• 공업화학
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• 제18권3호
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• pp.284-290
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• 2007

대두유로부터 생산된 바이오디젤과 바이오디젤 혼합 연료유를 대상으로 산화 특성과 지방산메틸에스터 함량 등 화학적 분석을 수행하여 자동차용 연료로서의 품질특성을 파악하였다. 대두유로부터 생산된 바이오디젤은 불포화 지방산인 oleic acid, linoleic acid 및 linolenic acid가 85 wt% 이상 함유되어 있었다. 특히 활성 메틸렌기를 함유한 다불포화 지방산인 linoleic acid와 linolenic acid가 60 wt% 이상 함유되어 있어 상대적으로 자동산화가 쉽게 일어나는 것으로 판단된다. 산화반응시 주요 반응물질은 linoleic acid와 linolenic acid였으며, 이들의 라디칼 자동산화에 의해서 비점이 약 $500^{\circ}C$ 전 후에 있는 탄소수 36 전 후의 고분자 물질이 형성되는 것을 확인하였다

• 한국수산과학회지
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• 제20권5호
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• pp.419-430
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• 1987

지질산화생성물에 의한 DNA손상작용 및 그 억제 기구를 밟히기 위하여 linoleic acid와 plasmid DNA와의 모델계를 통하여 검토하였는데, 그 결과를 요약하면 다음과 같다. 1. Linoleic acid의 산화에 의하여 DNA가 손상되었으며, 그 정도는 linoleic acid의 양이 많을 수록 크게 나타났다. 2. Linoleic acid의 산화에 의한 DNA손상작용은 POV 100 mea/kg이하인 산화초기에서도 빠르게 진행되었다. 산화초기의 DNA손상작용에는 활성산소 종의 관여가 크게 나타났는데, 그 중에서도 일중항 산소와 superoxide anion의 영향이 큰 것으로 나타났다. 3. 지질 2차반응생성물인 malonaldehyde와 hexanal의 DNA손상작용은 linoleic acid경우와는 달리 활성산소종과는 무관하였으며 DNA와 와의 복합체형성에 의하였다. 4. Linoleic acid hydroperoxide의 DNA 손상작용은 linoleic acid의 초기신화에 의한 DNA손상작용 보다 크게 나타났고, 활성산소종의 영향은 없었다. 5. 지진산화생성물에 의한 DNA손상 작용은 천연 항산화성분(마늘 및 생강추출물) 및 활성산소소거제($\alpha-tocopherol 및 superoxide dismutase$의 첨가에 의하여 크게 억제되었다. 특히 . 마늘 및 생강추출물은 활성산소종의 생성을 비롯하여 공액 diene 및 POV의 증가 또한 크게 억제하였다.

• 한국식품영양과학회지
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• 제24권2호
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• pp.202-207
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• 1995

The effects of lipoxygenase, linoleic acid, tocopherol and pH on the co-oxidation of $\beta$-carotene in the aqueous system were studied. It showed that the co-oxidation of $\beta$-carotene was noticeable at both pH 7.4 and 9.0. As the concentraitons of linoleic acid and $\beta$-carotene increased, the rate of oxidation of $\beta$-carotene tended to be increased. However, $\alpha$- and $\delta$-tocopherol retarded the co-oxidation of $\beta$-carotene. As the concentrations of tocopherols increased, $\beta$-carotene was more stabilized, generally. But low concentration of $\alpha$-tocopherol(10-4M) acted more effective antioxidant than high concentration of it(10-3M) at pH 7.4. The antioxidant effect of tocopherol greatly depended on pH ; it was outstanding at pH 7.4.

• 한국축산식품학회지
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• 제18권4호
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• pp.339-347
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• 1998

The effects of conjugated linoleic acid (CLA) in egg yolk on fatty acid composition and lipid oxidation during chilled storage (4$^{\circ}C$) were investigated. CLA was synthesized according to the method of alkali isomerization using safflower seed oil (SSO). A total of 250 hens (200 days of age) were fed control diet (commercial formula feed for han) or CLA-supplemented diet (1%, 2.5% and 5% CLA) or 5% SSO supplemented diet for 6 weeks, and eggs were collected for analysis of CLA, fatty acid compositons and lipid oxidation. Eggs from CLA-supplemented diets groups showed significantly (p＜0.05) higher CLA content compared to those of control group. The contents of linoleic, palmitic, and myristic acid were increased as well as CLA content by feeding a CLA-supplemented diet. However, the contents of oleic and arachidonic acids in egg yolks were decreased by dietary CLA supplementation. The pH of egg yolk increased by the levels of CLA during storage. The contents of CLA were not significantly (p＜0.05) changed during chilled storage for 28 days, whereas TBARS were significantly (p＜0.05) increased. It is suggested that lipid oxidation of egg yolk might be affected by the levels of CLA in egg yolk due to changes in fatty acid compositions.

• Journal of Nutrition and Health
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• 제30권9호
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• pp.1067-1072
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• 1997

One known effect of long chain n-3 polyunsaturated fatty acids is their ability to decrease plasma triglycerides. However, identification of the specific n-3 fatty acids and the underlying mechanisms responsible for this change remains uncertain. This present study was designed to evaluate the effects of moderate levels of dietary docosahexaenoic acid (22 :6(n-3)) on modulating plasma triglyderides. Male CD-1 mice were maintained for 15 days on identical diets containing either docosahexahexaenoic acid ethyl ester(1.5%, w/w) or linoleic acid(18 : 2(n-6)) ethyl ester (1.5%, w/w) . Plasma triglycerides were 40% lower in the docosahexaenoic acid group than in the linoleic acid group. Hepatic carnitine palmitoyltransferase activity (a key regulatory enzyme for mitocondria $\beta$-oxidation) was not significantly different between the dietary groups. However, plasma acid soluble acylcarnitine levels (which increase with increasing $\beta$-oxidation )were significantly higher in the decosahexaenoic acid group. This data suggests that plasma triglyceride levels are lower in mice fed diets containing moderate levels of docosahexaenoic acid compared to linoleic acid, but this effect on plasma triglycerides is not modulated through an augmentation of mitochondrial $\beta$-oxidation.

• 동아시아식생활학회지
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• 제3권2호
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• pp.147-153
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• 1993

Phenolics as antioxidant were added to linoleic acid to prevent lipid oxidation. Antioxidative effectiveness of them was measured by peroxie value at each 24hour interval in order to compare with 0.02% protocatechuic acid(PRL) and phloroglucinol(PHL) in linloleic acid, contrast tube at 37$^{\circ}C$for 96 hours blowing oxygen into specimen. Perocide values of oxidized linoleic acid, PRL, PHL for 96 hours were 78, 42, 30, From that the effect is more clearly demonstrated by NMR rather than UV and that the effect was dependent on the functional group and geometric molecular structure of phenolics.

• 한국식품과학회지
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• 제33권4호
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• pp.497-500
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• 2001

본 연구의 목적은 홍미삼의 기능성 연구의 일환으로 총 페놀성 화합물의 추출방법과 DPPH에 대한 수소공여능, linoleic acid의 산화방지활성 및 LDL에 의한 항산화활성 등을 중심으로 연구한 결과이다. 홍미삼에 60% 에탄올를 첨가하여 추출회수별 총 페놀성 화합물을 조사한 결과 3회까지 추출했을 때 대부분이 추출되었기 때문에 추출횟수는 3회가 적당한 것으로 판단되었다. 60% 에탄올 추출액의 수율은 3회까지 추출했을 때 약 37.35%가 추출되었다. 추출 용매에 따른 총 페놀성 화합물의 추출 효율은 물 추출구를 100%로 했을 때, 60% 에탄올 용액으로 추출한 뒤 농축하여 물로 부피를 재조정한 시험구는 122%로 조사되었다. 항산화활성 조사에서 DPPH에 대한 수소공여능에서 시간이 경과함에 따라 항산화 활성이 약간씩 증가하나 활성은 약한 편이었다. Linoliec acid 산화에 대한 산화억제 효과는 1,500 ppm 농도에서 약 72.23%의 저해율을 나타났으며, LDL에 대한 산화방지 효과는 250 ppm 농도에서 그 저해율이 약 22.52%로 나타났다.

• 한국응용과학기술학회지
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• 제4권2호
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• pp.25-30
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• 1987

In order to investigate the effect to antioxygenic substances in Pine Needles on the photooxidation of linoleic acid (linoleic acid 100mg/10ml ethanol) added antioxidants and antioxygenic substances in Pine Needles was irradiated by the tungsten lamp attached with red fitter. The Photo oxidation of linoleic acid (LA) was conformed with Lea method and rhodan method. The following results were obtained: 1. Photooxidation of LA was greatly increased the presence of photosensitizer. However the Photo oxidation of LA without photosensitizer was smoothly increased by the irradiation. 2. The Photo oxidation of LA without irradiation occured quite lately whether photosensitizer was present or absent. 3. Photooxidation of LA under the presence of photosensitizer was inhibited by the addition of $dl-{\alpha}-tocopherol$ and the acetone fraction of methanol extract of Pine Needles but inhibited by BHT. Photooxidation of LA increased gradually as the addition of BHT increased but decreased gradually as that of acetone fraction increased.

• 한국식품영양학회지
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• 제13권4호
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• pp.360-364
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• 2000

유지에 존재하는 linoleic acid의 전기화학적 산화/환원으로부터 속도론적 인자를 예측하고, 시간 변화에 대한 산패 정도를 조사하였다. Linoleic acid의 전기 화학적 산화환원 반응은 비가역적이고, 확산지배적으로 진행됨을 알 수 있고, 주사속도에 따른 결과로부터 확산계수 $D_{o}$ 는 2.61$\times$$10^{-6}$이고, 속도상수 $K^{o}$ 는 9.79$\times$$10^{-11}$로 주어짐을 예측하였다. 또한 linoleic acid의 산화반응 영역과 환원반응 영역에서 작업전극의 선택도가 달라짐을 볼 수 있다. 대기중 방치시간에 따른 시험 결과 방치한 지 4일을 전후로 산화 peak가 최대값으로 주어졌다. 특정 Peak에서 일정전위 전기분해 한 후 전기분해 생성물을 분석한 결과 carbonyl group이 생성됨을 예측할 수 있었다.

• 한국축산식품학회지
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• 제43권2호
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• pp.220-231
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• 2023

Although omega-3 fatty acids including docosahexaenoic acid (DHA) contain various health-promoting effects, their poor aqueous solubility and stability make them difficult to be induced in dairy foods. The aims of this research were to manufacture casein derivative-based delivery system using acid-induced gelation method with glucono-σ-lactone and to investigate the effects of production variables, such as pH and charged amount of linoleic acid, on the physicochemical properties of delivery systems and oxidative stability of DHA during storage in model milk. Covalent modification with linoleic acid resulted in the production of casein derivatives with varying degrees of modification. As pH was reduced from 5.0 to 4.8 and the charged amount of linoleic acid was increased from 0% to 30%, an increase in particle size of casein derivative-based delivery systems was observed. The encapsulation efficiency of DHA was increased with decreased pH and increased charged amount of linoleic acid. The use of delivery system for DHA resulted in a decrease in the development of primary and secondary oxidation products. An increase in the degree of modification of casein derivatives with linoleic acid resulted in a decrease in the formation of primary and secondary oxidation products than of free DHA indicating that delivery systems could enhance the oxidative stability of DHA during storage in model milk. In conclusions, casein derivatives can be an effective delivery system for DHA and charged amount of linoleic acid played a key role determining the physicochemical characteristics of delivery system and oxidative stability of DHA.