• BMB Reports
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• 제35권5호
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• pp.494-497
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• 2002

The present study explored the short-term effects of dietary conjugated-linoleic acid (CLA) on liver lipid metabolism in starved/refed Otsuka Long Evans Tokushima Fatty (OLETF) rats. Male OLETF rats (12 weeks old) were starved for 24 hours, then refed for 48 hours with either a CLA diet [7.5% CLA and 7.5% Safflower oil (SAF)] or a SAF control diet (15% SAF). The results demonstrated a 30% reduction of hepatic triglyceride (TG) concentration in the CLA group when compared to the control group. Liver cholesterol concentration was also 26% lower in the CLA fed rats. The activity of mitochondrial carnitine palmitoyltransferase, the rate-limiting enzyme of fatty acid oxidation, was moderately elevated by 1.2-fold in the livers of the CLA group when compared to the control. In contrast, phosphatidate phosphohydrolase, the rate-limiting enzyme for TG synthesis, was found to be 20% lower in the livers of the CLA-fed rats. Therefore, dietary CLA evidently lowers liver lipid concentrations through a reduced TG synthesis and enhanced fatty acid oxidation in starved/refed OLETF rats.

• Applied Biological Chemistry
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• 제36권4호
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• pp.284-289
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• 1993

탈검, 탈산, 탈색과 탈취 등의 정제과정이 $70^{\circ}C$에 저장하는 동안 참기름의 유지 특성과 산화안정성에 미치는 효과에 대하여 시험하였다. 정제과정을 거친 후 참기름의 색도(L, a, b)는 크게 변하여 엷어졌다. 지방산 조성, 굴절율, 요오드가와 conjugated dienoic acid의 변화는 없었고, 산가와 과산화물가는 감소하였다. $70^{\circ}C$에서 저장동안 탈산, 탈색과 탈취기름은 갈변화 반응이 급격히 이루어져 L값이 크게 감소하고 a값은 크게 증가하였다. 조유와 탈검시료는 색도가 안정하고, 과산화물가, 유리지방산과 conjugated dienoic acid 함량은 서서히 증가한 반면, 탈산, 탈색 및 탈취등의 정제과정을 거친 시료들은 저장초기에 이들의 값이 급격히 증가하였다. 저장 중 산화가 진행되면서 산패취에 관여하는 몇 개의 peak가 생성되고 양이 증가하는 것을 볼 수 있었는데 탈색과 탈취시료는 이들 peak의 증가가 저장초기에 매우 현저하였으나 조유와 탈검시료는 이들 peak의 변화가 거의 없었다.

• 대한본초학회지
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• 제27권2호
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• pp.53-59
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• 2012

Objectives : This study was undertaken to investigate the effects of the GGEx18 ethyl acetate fraction (EF) on lipid accumulation and gene expression of fatty acid-oxidizing enzymes using 3T3-L1 adipocytes, C2C12 skeletal muscle cells, and NMu2Li liver cells. Methods : PPAR${\alpha}$, AMPK and UCPs transactivation was examined in NMu2Li hepatocytes, C2C12 myocytes, and 3T3-L1 preadipocytes using transient transfection assays. Results : 1. Compared with control, EF significantly increased the mRNA expression of VLCAD in 3T3-L1 adipocytes. 2. Compared with control, EF (0.1 ${\mu}g/ml$) significantly inhibited lipid accumulation in 3T3-L1 adipocytes. 3. EF significantly increased the mRNA expression of AMPK${\alpha}$1, AMPK${\alpha}$2 and PPAR${\alpha}$ in C2C12 skeletal muscle cells compared with control. 4. EF significantly increased the mRNA expression of genes involved in fatty acid ${\beta}$-oxidation, such as thiolase, MCAD, and CPT-1 in C2C12 skeletal muscle cells compared with control. 5. EF significantly increased the mRNA expression of UCP2 involved in energy expenditure in C2C12 skeletal muscle cells compared with control. 6. Compared with control, EF (10 ${\mu}g/ml$) significantly inhibited lipid accumulation in C2C12 skeletal muscle cells. 7. EF (10 ${\mu}g/ml$) significantly increased the mRNA expression of ACOX, HD, VLCAD and MCAD in NMu2Li liver cells compared with control. Conclusions : These results suggest that EF may prevent obesity by increasing the mRNA expression of mitochondrial fatty acid ${\beta}$-oxidizing enzymes in 3T3-L1 adipocytes, by not only regulating the fatty acid oxidation through activation of AMPK and PPAR${\alpha}$, but also increasing the UCP2 mRNA expression in C2C12 skeletal muscle cells, and by stimulating the mRNA expression of fatty acid-oxidizing enzymes in NMu2Li liver cells.

• 한국축산식품학회지
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• 제44권1호
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• pp.103-118
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• 2024

The aim of this study is to compare the quality characteristics of dry-cured loins with different levels of proteolysis and lipid oxidation and to investigate the relationship between these factors on quality characteristics. The dry-cured loins were divided into four groups [proteolytic index (PI) and 2-thiobarbituric acid reactive substances (TBARS) of high levels (HH), PI of high level and TBARS of low level (HL), PI of low level and TBARS of high level (LH), and PI and TBARS of low levels (LL)] based on the proteolysis index and TBARS. Moisture, protein, and fat content were all significantly influenced by proteolysis and lipid oxidation (p<0.05). The total fatty acid content in the high proteolysis groups (HH and HL) was significantly lower than that in the low proteolysis groups (LH and LL; p<0.05). For total free amino acid content, HH was the highest, and LL was the lowest (p<0.05). On the other hand, there was no significant difference between HL and LH (p>0.05). In the amount of total volatile compounds, there was no significant difference between HH and HL (p>0.05), but LH and LL significantly differed (p<0.05). In conclusion, proteolysis and lipid oxidation can influence the quality characteristics of dry-cured loin. Additionally, proteolysis might be as influential in generating volatile compounds as lipid oxidation.

• Asian-Australasian Journal of Animal Sciences
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• 제32권11호
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• pp.1789-1800
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• 2019

Objective: Although alveolar macrophages play a key role in the respiratory immunity of livestock, studies on the mechanism of differentiation and survival of alveolar macrophages are lacking. Therefore, we undertook to investigate changes in the lipid metabolism and survival rate, using 3D4/31 macrophages and Dudleya brittonii which has been used as a traditional asthma treatment. Methods: 3D4/31 macrophages were used as the in vitro porcine alveolar macrophages model. The cells were activated by exposure to phorbol 12-myristate 13-acetate (PMA). Dudleya brittonii extraction was performed with distilled water. For evaluating the cell survival rate, we performed the water-soluble tetrazolium salt cell viability assay and growth curve analysis. To confirm cell death, cell cycle and intracellular reactive oxygen species (ROS) levels were measured using flow cytometric analysis by applying fluorescence dye dichlorofluorescein diacetate and propidium iodide. Furthermore, we also evaluated cellular lipid accumulation with oil red O staining, and fatty acid synthesis related genes expression levels using quantitative polymerase chain reaction (qPCR) with SYBR green dye. Glycolysis, fatty acid oxidation, and tricarboxylic acid (TCA) cycle related gene expression levels were measured using qPCR after exposure to Dudleya brittonii extract (DB) for 12 h. Results: The ROS production and cell death were induced by PMA treatment, and exposure to DB reduced the PMA induced downregulation of cell survival. The PMA and DB treatments upregulated the lipid accumulation, with corresponding increase in the acetyl-CoA carboxylase alpha, fatty acid synthase mRNA expressions. DB-PMA co-treatment reduced the glycolysis genes expression, but increased the expressions of fatty acid oxidation and TCA cycle genes. Conclusion: This study provides new insights and directions for further research relating to the immunity of porcine respiratory system, by employing a model based on alveolar macrophages and natural materials.

• Journal of Ginseng Research
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• 제32권3호
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• pp.187-193
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• 2008

The present study was designed to investigate the anti-diabetic effect and mechanism of Korean red ginseng in C57BL/KsJ db/db mice. The db/db mice were divided into three groups: diabetic control group (DC), Korean red ginseng group (KRG, 100 mg/kg) and metformin group (MET, 300 mg/kg), and treated with drugs once per day for 10 weeks. Compared to the DC group, fasting blood glucose levels were decreased by 19.8% in KRG-, 67.7% in MET-treated group. With decreased plasma glucose and insulin levels, the insulin resistance index of the KRG-treated group was reduced by 27.6% compared to the DC group. The HbA1c levels in KRG and MET-treated groups were also decreased by 11.0% and 18.9% compared to that of DC group, respectively. Plasma triglyceride and non-esterified fatty acid levels were decreased by 18.8% and 16.8%, respectively, and plasma adiponectin and leptin levels were increased by 20.6% and 12.1%, respectively, in the KRG-treated group compared to those in DC group. Histological analyses of the liver and fat tissue of mice treated with KRG revealed significantly decreased number of lipid droplets and decreased size of adipocytes compared to the DC group. From the pancreatic islet double-immunofluorescence staining, we observed KRG has increased insulin contents, but decreased glucagon production. To elucidate action mechanism of KRG, effects on AMP-activated protein kinase (AMPK) and its downstream target proteins responsible for fatty acid oxidation and gluconeogenesis were explored in the liver. KRG activated AMPK and acetyl-coA carboxylase (ACC) phosphorylations, resulting in stimulation of fatty acid oxidation. KRG also caused to down regulation of SREBP1a and its target gene expressions such as FAS, SCD1 and GPAT. In summary, our results suggest that KRG exerted the anti-diabetic effect through AMPK activation in the liver of db/db mice.

• Food Science and Biotechnology
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• 제17권6호
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• pp.1228-1234
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• 2008

Having idea to develop more effective anti-diabetic agent from ginseng root, we comprehensively assessed the anti-diabetic activity and mechanisms of ginsam in C57BL/KsJ db/db mice. The db/db mice were divided into 4 groups; diabetic control (DC), ginsam at a dose of 300 or 500 mg/kg (GS300 or GS500) and metformin at a dose of 300 mg/kg (MT300). Ginsam was orally administered for 8 weeks. GS500 reduced the blood glucose concentration and significantly decreased an insulin resistance index. In addition, GS500 reduced the plasma non-esterified fatty acid, triglyceride, and increased high density lipoprotein-cholesterol as well as decreased the hepatic cholesterol and triglyceride. More interestingly, ginsam increased the plasma adiponectin level by 17% compared to diabetic control group. Microarray, quantitative-polymerase chain reaction and enzyme activity results showed that gene and protein expressions associated with glycolysis, gluconeogenesis, and fatty acid oxidation were changed to the way of reducing hepatic glucose production, insulin resistance and enhancing fatty acid $\beta$-oxidation. Ginsam also increased the phosphorylation of AMP-activated protein kinase and glucose transporter expressions in the liver and skeletal muscle, respectively. These changes in gene expression were considered to be the mechanism by which the ginsam exerted the anti-diabetic and anti-dyslipidemic activities in C57BL/KsJ db/db mice.

• Asian-Australasian Journal of Animal Sciences
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• 제32권6호
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• pp.874-880
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• 2019

Objective: Ozone is considered a strong antimicrobial agent with numerous potential applications in the food industry. However, its high oxidizing potential can induce alterations in foods by acting on the unsaturated fatty acids. The aim of this study was to investigate the effect of ozonation on the oxidative stability of chicken breast meat obtained from animals subjected to different feeding strategies. Methods: Samples were obtained from commercial hybrid chickens (ROSS 508), some of which were nourished with a feed enriched with fats of animal origin, while the lipid source was vegetal for the remaining birds. Samples of meat belonging to both groups were treated with ozone and then analysis was performed to evaluate alterations in physical properties, lipid content, fatty acid profile, and oxidation stability. Results: Ozone induced a significant reduction in drip loss in meat samples obtained from animals nourished with vegetable fats; this nutritional strategy also produced meats leaner and richer in polyunsaturated fatty acids. Thiobarbituric acid reactive substances, useful for the assessment of lipid oxidation, were higher in samples obtained from animals fed with vegetable fats with respect to diet based on the addition of animal fats. Conclusion: The ozone treatment improved the physical parameters of meat samples obtained from animals fed with vegetable fats, however the same samples showed a higher lipid oxidation compared to what observed in the case of the dietary intake of animal fats, probably as a consequence of the marked increase in polyunsaturated fatty acids which are more susceptible to peroxidation.

• 한국응용과학기술학회지
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• 제35권4호
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• pp.1013-1030
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• 2018

바이오디젤은 동물성 유지, 식물성 유지와 그 부산물 등의 원료를 사용하여 지방산 메틸에스테르 형태로 제조된 연료이며, 석유계 에너지를 대체할 수 있는 바이오연료로 각광받고 있다. 그러나 바이오디젤은 저장 및 유통 과정에서 불포화 지방산 메틸에스테르가 산화되면서 연료의 품질이 저하되거나 자동차 엔진부품을 부식시키는 등의 문제를 일으킨다. 따라서 본 연구에서는 바이오디젤의 품질과 산화 특성이 산화 안정성에 미치는 영향을 알아보고, 이와 관련된 평가 방법에 대해 기술하였다. 또한 바이오디젤의 산화 안정성 단점을 개선할 수 있는 방안을 고찰하였다.

• 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.