• The Korean Journal of Zoology
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• v.22 no.1
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• pp.26-38
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• 1979

In recent years some very substantial advances have been made in our understanding of oogenesis as a result of studies on a relatively few, very diverse species of animals. In this lecture I will (1) outline normal oogenesis using an advanced insect, Drosophila melanogaster, as an example, (2) show how oogenesis can be dissected genetically by studying the ovarian pathologies of flies homozygous for various recessive, female sterile genes, and (3) discuss how estimates can be made of the fraction of the Drosophila genome devoted to oogenesis. Then I will describe studies on mutations that block vitello-genesis in Drosophila and indicate what they tell us about inter actions between the ovary, the fat body and the endocrine system. I will next discuss the evolutionary mechanisms that have been adopted in higher insects and amphibians to produce the prodigious quantities of ribosomes stored in oocytes. I will end with an account of the results of recent stuides on amphibian lampbrush chromosomes which show how messenger RNAs are transcribed during oogenesis.

• Proceedings of the Ginseng society Conference
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• 1993.09a
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• pp.110-112
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• 1993

Acidic polysaccharide from Korean red ginseng was found to inhibit pancreatic lipase activity and cause reduction of plasma triglyceride level after oral administration of corn oil emulsion to rats. Thus acidic polysaccharide may reduce plasma triglyceride through its inhibitory action on pancreatic lipase and successive inhibition of intestinal absorption of fat due to reduction of lipolysis. In the course of this experiment, we found an unknown ninhydrin positive substance in Korean red ginseng. The unknown substance was identified to be arginyl-fructosyl glucose(Arg - Fru - Glc). Coment of this new compound was $5.37\%$ in Korean red ginseng powder. Sucrase and maltase activities in mucous layer of rat jejunum were found to be inhibited by Arg-Fru-Glc. Physiological significance of the new compound was discussed based on these experimental results.

• Natural Product Sciences
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• v.17 no.3
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• pp.212-215
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• 2011

In the course of screening anti-adipogenic activity of natural products employing the preadipocyte cell line, 3T3-L1 as an in vitro assay system, the EtOAc fraction of the stem barks of Acer tegmentosum Maxim (Aceraceae) showed significant inhibitory activity on adipocyte differentiation as assessed by measuring fat accumulation using Oil Red O staining. Activity-guided fractionation led to the isolation of active constituent, (+)-catechin. (+)-Catechin showed inhibitory activity on adipocyte differentiation in dose-dependent manner. Further studies with interval treatment demonstrated that (+)-catechin exerted inhibitory activity on adipocyte differentiation via acting on early stage of adipogenesis. Our present study also showed that (+)-catechin significantly inhibited the preadipocyte proliferation. Taken together, these results suggest that (+)-catechin, a constituent of A. tegmentosum might contribute the anti-adipogenic activity of A. tegmentosum.

• Journal of the Korean Society of Food Science and Nutrition
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• v.27 no.4
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• pp.633-638
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• 1998

Fibrionolytic activity(FA) of kimchi in rat and FAs of water and methanol extracts of kimchi ingredient were determined using fibrin plate method to see where the active principles for FA are present in kimchi. Nine Sprague-Dawley per each group were fed diet containing 3, 5 or 10% of freeze dried kimchi for 6 weeks. The FA of plasma obtained from 10% kimchi group showed stronger FA than that of control. FAs of 3 and 5% kimchi group were not noticeable. FA from methanol extract of kimchi was approximately 6 times higher than that from water extract assuming that the active material may be present in a fat soluble fraction. From water extract of kimchi ingredients, dropwort, green onion, radish and baechu showed FA in descending order. And from methanol extracts, red pepper powder, radish, green onion and baechu showed FA in decending order. The Fa of methanol extract of red pepper powder was the most noticeable among samples.

• Journal of the Korean Society of Food Science and Nutrition
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• v.16 no.3
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• pp.27-34
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• 1987

The present paper was attempted to obtain the basic date concerning a reasonable preparing method and optimum fermentation conditions of Kochujang (Red pepper paste). To establish the standard quality of Kochujang, the chemical compositions and the volatile components of Kochujang was discussed. The native Kochujang collected from 80 households contained 40.51% of moisture, 6.00% of salts, 3.25 % of crude fat, 10.30 % of crude ash, pH 4.79, 9.28ml of tillable acidity. 19.60% of reducing sugar, 179.51 mg/100g of amino nitrogen and 4.43% of total nitrogen. The volatiles of Kochujang were extracted by a steam-distillation under the reduced pressure and determined by gas chromatography-mass spectrometry (GC-MS). Total volatile components identified in the native Kochujang were 46 components, i. e., 30 components in neutral fraction, 8 components in phenolic fraction and 8 components in acidic fraction, respectively. But no components were detected basic fraction.

• Korean Journal of Food Science and Technology
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• v.10 no.3
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• pp.313-319
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• 1978

In order to investigate the effect of dietary long chain fatty acids on fatty acid biosynthesis of liver in birds, single comb White Leghron male chicks were fed a fat-free diet an diets containing margaric, stearic and linoleic acids and liver lipid components and liver and plasma fatty acid distributions were compared. Total lipids of tissues were extracted with a chloroform-methanol mixture. The lipid components were determined by thin layer chromatography and fatty acid distribution of lipid fractions were determined by gas liquid chromatography. Fatty acid feeding did not affect liver lipid components. When margaric acid(17 : 0), was fed, 17:0 and heptadecenoic acid(17:1) appeared in every lipid fractions of liver and plasma, and distribution values of these acids were not significantly different between the lipid fractions of liver. In blood plasma of the 17 : 0 fed chicks, however, significantly higher distribution values of 17 : 0 and 17.1 were observed in the triglyceride fraction and in the cholesterol ester fraction, respectively. Dietary stearic acid (18 : 0) did not show any effect on the distribution of 18 : 0 in every lipid fractions of liver but showed a significantly higher distribution value of 18 : 0 in the free fatty acid fraction of plasma. When linoleic acid (18 : 2) was fed, every lipid fractions of liver and plasma contained 18 : 2, especially a significantly higher distribution value was observed in the phospholipid fraction of liver. Dietary margaric and linoleic acids tended to decrease the distribution value of endogenously synthesized palmitoleic (16 : 1) and oleic (18 : 1) acids in liver.

• Journal of Nutrition and Health
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• v.43 no.4
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• pp.342-350
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• 2010

This study was aimed to investigate whether soy protein hydrolysates had beneficial effects on serum and tissue lipid contents and appetite-related hormones as compared with intact soy protein. Four-week-old male Sprague-Dawley rats were fed AIN-93M diet containing high fat (18% w/w) with low protein (10% w/w). After four weeks, the rats were divided into four groups (n = 8/group) and fed experimental diets with different nitrogen sources and levels, respectively; 10% soy protein isolate (10SPI), 25% soy protein isolate (25SPI), 25% soy protein hydrolysates (25SPH) and 25% soy macro-peptide fractions (25SPP, MW $\geq$ 10,000) for six weeks. Weight gain was significantly higher in 25% nitrogen sources-fed groups than in 10% group (10SPI). In 25SPP, perirenal fat mass and serum total lipid were significantly lower than in other groups. As for appetite-related hormones, serum ghrelin concentration was not shown to be different among groups but leptin concentration was significantly decreased in 25SPP. It can be concluded that soy macro-peptide fractions as compared with intact soy protein may have beneficial effects on reducing fat mass and serum lipid.

• Journal of Preventive Medicine and Public Health
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• v.54 no.6
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• pp.412-421
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• 2021

Objectives: Non-alcoholic fatty liver disease (NAFLD) is an increasingly prevalent metabolic disease. Muscle is known to influence NAFLD development. Therefore, this study aimed to determine the relationships among low muscle mass, NAFLD, and hepatic fibrosis using various definitions of low muscle mass and NAFLD diagnostic methods, including magnetic resonance imaging-based proton density fat fraction (MRI-PDFF). Methods: This cross-sectional study included 320 participants (107 males, 213 females) from the Korean Genome and Epidemiology Study on Atherosclerosis Risk of Rural Areas in the Korean General Population cohort. Muscle mass was assessed using whole-body dual-energy X-ray absorptiometry and adjusted for the height squared, body weight, and body mass index (BMI). NAFLD was diagnosed using ultrasonography (US), MRI-PDFF, and the comprehensive NAFLD score (CNS). Hepatic fibrosis was assessed using magnetic resonance elastography. Multivariable logistic and linear regression analyses were performed to determine the aforementioned associations. Results: According to US, 183 participants (57.2%) had NAFLD. Muscle mass adjusted for body weight was associated with NAFLD diagnosed using US (odds ratio [OR], 3.00; 95% confidence interval [CI], 1.70 to 5.31), MRI-PDFF (OR, 2.00; 95% CI, 1.13 to 3.53), and CNS (OR, 3.39; 95% CI, 1.73 to 6.65) and hepatic fibrosis (males: β=-0.070, p<0.01; females: β=-0.037, p<0.04). Muscle mass adjusted for BMI was associated with NAFLD diagnosed by US (OR, 1.71; 95% CI, 1.02 to 2.86) and CNS (OR, 1.95; 95% CI, 1.04 to 3.65), whereas muscle mass adjusted for height was not associated with NAFLD. Conclusions: Low muscle mass was associated with NAFLD and liver fibrosis; therefore, maintaining sufficient muscle mass is important to prevent NAFLD. A prospective study and additional consideration of muscle quality are needed to strengthen the findings regarding this association.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.8
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• pp.1012-1017
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• 2017

Mesembryanthemum crystallinum (Family: Aizoaceae) is an annual plant consisting of ice crystal-shaped bladder cells, which is responsible for its common name ice plant. This study investigated biological activities according to general components and extraction solvent in order to examine the functionality of ice plant. The total content of free amino acids was 32.57 mg/g, including 4.64 mg/g of L-alanine as the most abundant and 2.60 mg/g of ${\gamma}$-aminobutyric acid. Regarding angiotensin converting enzyme inhibitory activities of solvent fractions of ice plant, ethyl acetate fraction and chloroform fraction showed activities of $33.17{\pm}3.20{\sim}88.19{\pm}3.20%$ and $23.72{\pm}2.89{\sim}86.78{\pm}2.24%$, respectively, similar to $Captopril^{(R)}$ ($19.51{\pm}3.44{\sim}84.72{\pm}1.06%$) and $Enalapril^{(R)}$ ($24.93{\pm}1.12{\sim}91.32{\pm}3.62%$) as positive control groups. Regarding inhibition of lipid droplet production in 3T3-L1 preadipocytes by ice plant, anti-adipogenic activities were $53.00{\pm}0.45{\sim}65.75{\pm}0.31%$ and $44.16{\pm}0.29{\sim}63.32{\pm}0.36%$ in the ethyl acetate fraction and butanol fraction, respectively, showing the lowest lipid droplet production. The chloroform fraction and hexane fraction showed activities of $38.33{\pm}0.09{\sim}56.55{\pm}0.50%$ and $31.17{\pm}0.50{\sim}55.10{\pm}1.93%$, respectively, whereas the water fraction showed activity of $26.32{\pm}2.27{\sim}49.48{\pm}0.05%$. Therefore, all solvent fractions inhibited fat accumulation of 3T3-L1 preadipocytes according to treatment concentration. According to the results above, it would be possible to utilize ice plant as a new health functional material.

• Korean Journal of Food Science and Technology
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• v.5 no.1
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• pp.36-41
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• 1973

Chemical changes with time of frying-fats during the frying process (beef tallow with 0.01% BHA and 0.01% BHT, turnover rate 9%/hr and $140{\pm}10^{\circ}C$ temperature) of Ramyon on a commercial scale were studied. No significant changes of carbonyl value and peroxide value were noted up to 120 hrs. However, small increases in acid value, color and dimeric fatty acid were noted. Small decreases in iodine value and the content of unsaturated fatty acids were also observed. Under the experimental storage condition, when the stability of fats heated were compared to fresh fat, minor differences in carbonyl value and weight gain were noted. All of these demonstrated that frying-fats commercially used in Ramyon frying system were maintained in good quality during the frying process.