• Journal of Nutrition and Health
• /
• v.26 no.6
• /
• pp.661-671
• /
• 1993

The change in fatty acid composition in brain tissue of the second generation rats(Sprague-Dawley strain) was studied using four different fat diets(Corn oil=CO, Soybean oil=SO, Perilla oil=PO, Fish oil=FO, 10% by Wt). The experimental diets were started from pregnancy in four different groups, each consisting of 9 rats. The seound generation rats were fed the same diet as their mothers. Animals were anesthetized with ether at 0, 3, 9 & 16 weeks of age. Whole brains were dissected out, brain tissues were, then, homogenized and lipids were extracted from brain tissues. The fatty acid compositions were measured after methylation by gas-liquid chromatography at 0, 3, 9 and 16 weeks of age of offspring. The changes in the relative concentrations of polyunsaturated fatty acids(PUFA) or more specifically docosahexaenoic acid(22 : 6, $\omega$3, DHA), the major $\omega$3 fatty acid component in rat brain at different age were similar to changes in the amount of DNA in brain tissue showing the maximum value during the lactation. The changes in saturated fatty acid(SFA) content showed a contrasting patten to those of PUFA, while monounsaturated fatty acid(MUFA) increased steadily throughout the experimental period. At birth, the relative concentrations of $\omega$3 series fatty acids the relative concentrations of PUFA, MUFA and SFA converged to very similar values respectively regardless of the dietary fatty acid compositions. In brain tissue, it is of value to note that while changes in relative concentrations of linoleic acid (18 : 2, $\omega$6, LA) and arachidonic acid(20 : 4, $\omega$6, AA) showed a precursor-product-like relationship, $\alpha$-linolenic acid(18 : 3, $\omega$3, $\alpha$-LnA) and DHA showed a different pattern. Even when the $\omega$3 fatty acid content in very low in maternal diet(CO), the second generation rat brain tissues appeared to secure DHA content, suggesting an essential role of this fatty acid in the brain. The fact that a large amount of $\alpha$-LnA in the maternal diet did not have a significant effect on the second generation rat brain $\alpha$-LnA content, indicated that DHA seemed essential component for the brain development in our experimental condition. In all groups, the relative content of $\alpha$-LnA in the brain tissues remained relatively constant throughout the experimental period at the very low level. The study of the specific concentrations and essential role(s) of DHA in each parts of brain tissue is needed in more details.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.45 no.3
• /
• pp.452-459
• /
• 2016

Nutritional compositions, volatile compounds, and sensory attributes of grilled and fast-chilled mackerel (Scomber japonicus) were analyzed in order to examine its practical utilization as a food resource compared to commercial frozen mackerel. In the proximate analysis, lipid contents were $27.3{\pm}2.7%$ in grilled and fast-chilled mackerel. Palmitic acid was the most predominant fatty acid (20.68% and 18.88%), and the percentages of polyunsaturated fatty acid were higher than 40% in both. No benzopyrene was found in the grilled mackerel, and even grilling was employed at $260^{\circ}C$. For chemical stabilities, para-anisidine value (8.56 vs. 9.26) and acid value (2.96 vs. 3.35) in grilled mackerel were improved compared to those of commercial mackerel. Moreover, color index of grilled mackerel, a physiological property, showed greater lightness than commercial mackerel. Lastly, analysis of volatile compounds by gas chromatographic analysis and sensory tests by trained panels demonstrated higher potential for grilled mackerel as a highly marketable product compared to commercial mackerel. Taken altogether, the above results provide important preliminary results for utilization of grilled and fast-chilled mackerel as a quality food.

• Food Science and Preservation
• /
• v.14 no.2
• /
• pp.154-159
• /
• 2007

In efforts to use pine needle extract as a substitute for sugar, fermented pine needle extract syrup was added to the wheat flour nea in the manufacture of white bread The extract was added to levels of 8.3%, 11% and 18% of total weight based on the Brix degree of the dough The cohesion of each dough was checked, and the physical properties and storage stabilities of the baked breads were analyzed during storage at mom temperature. Analysis of the cohesion of each dough by farinogram showed that dough with pine needle extract was better than dough with sugar, in terms of both stability and durability of mixing. The pH of dough with syrup was steady during storage at pH 5.4 5.8, which is favorable for yeast activity. The dough with syrup also showed low firmness and good extensibility, both of which would favorably affect gas retention on fermentation. Increases in syrup addition resulted in higher product volumes. Bread with syrup was slow to increase in hardness during storage, suggesting that higher syrup concentrations inhibited development of staleness. The addition of syrup also inhibited the growth of aerobic bacteria and mold on the bread surface. The addition of syn did not cause any negative effect. The use of pine none extract syrup may thus contribute to improvements the physical properties, the storage stability, and the hygienic quality of bread.

• Journal of the Korean Applied Science and Technology
• /
• v.35 no.4
• /
• pp.1073-1080
• /
• 2018

There are several types of petroleum products used for the fuel oil, according to their respective quality standards, grades and usage. Depending on the degree of oil tax rate by country, even the same petroleum products will have price gap. The illegal mixing of cheap petroleum products, which are subject to the lower tax rate, with relatively expensive transportation fuel causes problems such as tax evasion, environmental pollution and vehicle breakdown. In order to prevent illicit production and mixing of these different petroleum products, a small amount of markers are legally added to specific petroleum products. In Korea, markers are introduced and used to prevent illegal activity that kerosene used as fuel for house and commercial boiler are mixed with automotive diesel fuels, and marker contents are analyzed to use UV-Vis spectrophotometer and high performance liquid chromatography (HPLC). In this study, we have developed a method to qualitatively and quantitatively determine the marker added to petroleum products by gas chromatography-mass spectrometry (GC-MS) without adding developing reagent or sample pre-treatments.

• Journal of Life Science
• /
• v.28 no.12
• /
• pp.1523-1528
• /
• 2018

This study investigated the chemical composition of four Korean cultivated Chrysanthemum indicum L. (Gamguk 1 ho, Gamguk 2 ho, Gamguk 3 ho, and Wonhyang) which are used in the food and fragrance industries to identify their volatile flavor compounds. These compounds were analyzed using headspace GC-MS from plant samples cultivated in the same region of Korea (Sancheong-gun, Gyeongsangnam-do). A total of 23 compounds were identified, eight of which were common across the four cultivars. The major flavor components in the three Gamguk plants were identified as 3-carene, camphene, ${\beta}$-phellandrene, eucalyptol and (+)-camphor. Eleven compounds, including (+)-camphor at 31.40%, were identified in Gamguk 1 ho. Gamguk 2 ho was found to contain 12 flavor compounds, predominant of which was camphene at 25.60%. Thirteen compounds including (+)-camphor (26.88%) were identified in Gamguk 3 ho, while 17 were detected in the Wonhyang cultivar, including trans-piperitol (47.33%), sabinene, and ${\gamma}$-terpinyl acetate. These results indicate differences in the type and ratio of functional volatile flavor ingredients in Chrysanthemum indicum L. cultivars which is highly valuable as material for fragrance product development.

• Korean Chemical Engineering Research
• /
• v.57 no.5
• /
• pp.611-619
• /
• 2019

This study was carried out to investigate fuel decomposition characteristics and coke formation according to types of endothermic fuels and methods of catalyst molding. Methylcyclohexane (MCH), n-dodecane, and exo-tetrahydrodipentadiene (exo-THDCP) were used as the endothermic fuels. As a catalyst, USY720 supported with platinum was used. It was manufactured by only using pressure to disk-type, or pelletized with a binder and a silica solution. The characteristics of the catalysts according to the molding method were analyzed by X-ray diffraction analysis, scanning electron microscopy, nitrogen adsorption-desorption isotherm, and ammonia temperature programmed desorption analysis. The reaction was carried out under conditions of high temperature and high pressure ($500^{\circ}C$, 50 bar) in which the fuel could exist in a supercritical state. The product was analyzed by gas chromatograph/mass spectrometer and the coke produced by the catalyst was analyzed by thermogravimetric analyzer. After the reaction, the composition of the products varied greatly depending on the structure of the fuel. In addition, the crystallinity and surface properties of the catalysts were not changed by the method of catalyst molding, but the changes of the acid sites and the pore characteristics were observed, which resulted in changes in the amount and composition of products and coke.

• Journal of the Korea Organic Resources Recycling Association
• /
• v.29 no.2
• /
• pp.31-38
• /
• 2021

The aim of this study is to evaluate the possibility of treating slaughterhouse by-products using microbial electrolysis cells (MECs). The diluted pig liver was fed to MEC reactors with the influent COD concentrations of 772, 1,222, and 1,431 mg/L, and the applied voltage were 0.3, 0.6, and 0.9 V. The highest methane production of 5.9 mL was obtained at the influent COD concentration of 1,431 mg/L and applied voltage of 0.9 V. In all tested conditions, COD removal rate was increased as the influent COD concentration increased with average removal rate of 62.3~81.1%. The maximum methane yield of 129~229 mL/g COD was obtained, which is approximately 80% of theoretical maximum value. It might be due to the bioelectrochemical reaction greatly increased the biodegradability of pig liver. Future research is required to improve the methane yield and digestibility through optimizing the reactor design and operating conditions.

• Applied Chemistry for Engineering
• /
• v.22 no.5
• /
• pp.562-565
• /
• 2011

In this study, we developed a bioprocess using Clostridium ljungdahlii as a biological catalyst to produce bio-ethanol, and the effect of pH on microbial growth and ethanol production was investigated. From the results of fermentation at various initial pH condition without pH control, pH of fermentation broth decreased to 4.5 within 24 h due to accumulation of by-product acetic acid and both microbial growth and ethanol production were stopped. The experimental result of initial pH 8 showed the highest microbial growth and ethanol production (0.53 g/L), since the pH drop was relatively slow. From the experiment of pH 7 maintained fermentation using pH controllable bioreactor, the maximum cell dry weight of 1.65 g/L and the maximum ethanol concentration of 1.43 g/L were obtained within 24 h. In conclusion, the C. ljungdahlii growth was enhanced by pH maintenance of neutral range, and the ethanol production was also enhanced based on the growth-associated ethanol production characteristics of C. ljungdahlii.

• Animal Bioscience
• /
• v.34 no.4
• /
• pp.662-669
• /
• 2021

Objective: Effects of linseed oil (LO) supplementation on the fat content and fatty acid profile of breast meat, and the expression of three genes in the liver, breast muscle and fat tissues of commercial 154-day-old hybrid male turkeys were investigated. Methods: The animals in the control group were fed a commercially available feed and received no LO supplementation (n = 70), whereas animals in the LO group (n = 70) were fed the same basic diet supplemented with LO (day 15 to 21, 0.5%; day 22 to 112, 1%). The effect of dietary LO supplementation on fatty acid composition of breast muscle was examined by gas chromatography, and the expression of fatty acid desaturase 2 (FADS2), peroxisome proliferator activated receptor gamma (PPARγ), and insulin-like growth factor 1 (IGF1) genes was analysed by means of quantitative reverse transcription polymerase chain reaction. Results: The LO supplementation affected the fatty acid composition of breast muscle. Hepatic FADS2 levels were considerably lower (p<0.001), while adipose tissue expression was higher (p<0.05) in the control compared to the LO group. The PPARγ expression was lower (p<0.05), whereas IGF1 was higher (p<0.05) in the fat of control animals. There were no significant (p>0.05) differences in FADS2, PPARγ, and IGF1 gene expressions of breast muscle; however, omega-6/omega-3 ratio of breast muscle substantially decreased (p<0.001) in the LO group compared to control. Conclusion: Fatty acid composition of breast meat was positively influenced by LO supplementation without deterioration of fattening parameters. Remarkably, increased FADS2 expression in the liver of LO supplemented animals was associated with a significantly decreased omega-6/omega-3 ratio, providing a potentially healthier meat product for human consumption. Increased PPARγ expression in fat tissue of the LO group was not associated with fat content of muscle, whereas a decreased IGF1 expression in fat tissue was associated with a trend of decreasing fat content in muscle of the experimental LO group.

• Membrane Journal
• /
• v.32 no.4
• /
• pp.218-226
• /
• 2022

Hydrogen, a carrier of large-capacity chemical and clean energy, is an important industrial gas widely used in the petrochemical industry and fuel cells. In particular, hydrogen is mainly produced from fossil fuels through steam reforming and gasification, and carbon dioxide is generated as a by-product. Therefore, in order to obtain high-purity hydrogen, carbon dioxide should be removed. This review focused on free-standing polymeric membranes and mixed-matrix membranes (MMMs) that separate hydrogen from carbon dioxide reported in units of Barrer [1 Barrer = 10^-10 cm³ (STP) × cm / (cm² × s × cmHg)]. By analyzing various recently reported papers, the structure, morphology, interaction, and preparation method of the membranes are discussed, and the structure-property relationship is understood to help find better membrane materials in the future. Robeson's upper bound limits for hydrogen/carbon dioxide separation were presented through reviewing the performance and characteristics of various separation membranes, and various MMMs that improve separation properties using technologies such as crosslinking, blending and heat treatment were discussed.