• Applied Chemistry for Engineering
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• v.29 no.4
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• pp.461-467
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• 2018

In this study, $(n-BuCp)_2ZrCl_2$, was supported on $SiO_2/MgCl_2$ binary support. Before supporting the catalyst, the $SiO_2/MgCl_2$ binary support was surface treated with three different alkyl aluminum compound, namely trimethylaluminum, triethylaluminum, and ethylaluminum sesquichloride. The synthesized surface-treated $SiO_2/MgCl_2$ supported metallocene catalysts were used for the copolymerization of ethylene and 1-hexene. Their catalytic properties and performances were analyzed through BET, XPS analysis, ICP-AES analysis, and FE-SEM. While the resulting copolymers were analyzed through DSC analysis, GPC analysis, 13C-NMR analysis, and FE-SEM. The analysis of synthesized surface-treated $SiO_2/MgCl_2$ supported metallocene catalysts showed that the Zr content of these catalysts is relatively lower compared to that of the catalyst supported on $SiO_2$. This could be attributed to the reduction in the surface area of $SiO_2$ due to the presence of recrystallized $MgCl_2$ and alkyl aluminum. Furthermore, they exhibited a better copolymerization activity compared to that of $SiO_2$ supported catalyst, particularly the EASC-surface treated binary support, which has the highest activity of 1.9 kg PE/($mmol-Zr^*hr$) because EASC acts as a strong Lewis acid. It could also be observed that the larger the ligand of alkyl aluminum used, the rougher the particle surface of the resulting polymer.

• Food Science of Animal Resources
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• v.31 no.3
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• pp.451-459
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• 2011

We investigated melting points and sensory characteristics by adding rice bran and roasted soybean to the finishing diet of Hanwoo steers. Thirty-six Hanwoo steers (average age, 20.92 mon-old; average weight, 599.89 kg) were assigned to either Control, Treatment 1 (rice bran) or Treatment 2 (roasted soybean) groups (12 steers/group), considering body weight and age. Supplementation levels of rice bran and roasted soybean were determined to meet total 5% crude fat in the concentrates, and the experimental animals were fed for 314 d until they reached 31.2 mon old. No significant differences were found in the moisture and crude fat content among groups. Melting points of lipid extracted from M. longissimus dorsi, subcutaneous fat, and perirenal fats were 25.83-26.17, 17.26-18.53 and $32.40-33.15^{\circ}C$, respectively, resulting in remarkable differences depending on fat depots. Contents of free amino acids in M. longissimus dorsi related to sweet taste were 39.48 mg/100 g for Treatment 1, which was significantly (p<0.05) higher than those for Control (32.24 mg/100 g), whereas those related to bitter taste were 25.93 mg/100 g for Treatment 2, which was the lowest (p<0.05) among the groups. Fatty acid composition, such as $C_{14:0}$, $C_{16:0}$, $C_{16:1}$, $C_{18:0}$, and $C_{18:1}$, in M. longissimus dorsi was not different among the groups. Results of a panel test on M. longissimus dorsi showed that Treatment 1 scored the highest (p<0.05) in juiciness, and both Treatments 1 and 2 scored higher (p< 0.05) in overall palatability than the Control group. $C_{18:1}$ showed a positive (+) relationship with tenderness (r = 0.650; p<0.05), and $C_{18:0}$ with flavor (0.698; p<0.05). The results suggest that rice bran and roasted soybean are beneficial for improving M. longissimus dorsi sensory characteristics, whereas no significant differences were found in the physico-chemical characteristics among the groups.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.8
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• pp.1087-1096
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• 2010

This study was conducted to investigate the physiological activity of extracts of fresh mushrooms. The components were extracted by hot water; subsequently, the hot-water extract was subjected to 60% ethanol precipitation to yield high-molecular-weight (HMW) and low-molecular-weight (LMW) fractions. Total polyphenol contents, $\beta$-glucan contents, electron-donating ability (EDA), superoxide dismutase (SOD)-like activity, nitrite-scavenging activity, fibrinolytic activity, nitric oxide (NO) production, and inhibition of NO production of the mushroom extracts were measured using lipopolysaccharide (LPS)-stimulated murine macrophages, RAW 264.7 cells. The extracts of Lentinus edodes (Berk.) Singer and Pleurotus ostreatus (Fr.) Kummer contained the highest levels of $\beta$-glucan (33.5% and 25.57%, respectively). Further, the LMW fractions of the Phellinus linteus contained the highest levels of polyphenols (233.23 mg/g). The EDA of LMW fractions (10 mg/mL) of the Phellinus linteus and Agaricus bisporus were 80.74% and 51.35%, respectively. Further, SOD-like activities of the LMW fractions were high as compared to those of the HMW fractions. Nitrite-scavenging activities of the LMW fractions (pH 1.2; concentration, 10 mg/mL) of the Phellinus linteus and Pleurotus ostreatus (Fr.) Kummer were 75.95% and 41.05%, respectively. The fibrinolytic activity of the LMW fractions of all mushrooms showed no enzyme activity by fibrin plate assay. The fibrinolytic activity of the extracts of Tricholoma matsutake was the greatest inhibitory activity at 60.4%. Further study revealed that the mushroom extracts exhibited anti-inflammatory effects on RAW 264.7 cells. The LMW fraction ($500\;{\mu}g/mL$) of the Phellinus linteus considerably inhibited NO production (100%).

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.5
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• pp.641-649
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• 2014

This study was carried out to investigate the effects of Peucedanum japonicum Thunb. (PJT) powder on lipid metabolism and antioxidative activity in rats fed a high-fat/high-cholesterol diet for 4 weeks. Male Sprague-Dawley rats were assigned to four groups: normal diet group (N), high-fat/high-cholesterol group (HFC), high-fat/highcholesterol with 5% PJT powder (HFC-PBL), and high-fat/high-cholesterol with 10% PJT powder (HFC-PBH). Body weight gain and food efficiency ratio (FER) increased in the HFC group, whereas they gradually decreased in the PJT powder-fed groups. Food intake was not significantly different between the experimental groups. Liver and adipose tissue weights of the HFC group were heavier than that of the N group, whereas the groups fed PJT powder showed gradual reduction of tissue weights. Serum alkaline phosphatase (ALP) activity significantly decreased after PJT powder administration. Serum triglyceride level significantly decreased in groups fed PJT powder compared to the HFC group. The serum low density lipoprotein cholesterol (LDL-cholesterol) level of the HFC group increased by 73.70% than that of the N group, whereas serum high density lipoprotein (HDL-cholesterol) tended to decrease in groups fed PJT powder compared to the HFC group. Levels of triglycerides in epididymal and mesenteric adipose tissues, as well as cholesterol levels in liver and adipose tissues were lower in the groups fed 10% PJT powder compared to the HFC group. The liver glutathione (GSH) level increased in the groups fed PJT powder compare to the HFC group. The liver thiobarbituric acid reactive substances (TBARS) content significantly decreased in the groups fed PJT powder compared to the HFC group. These results suggest that PJT powder may improve lipid metabolism in the serum, liver, and adipose tissue and prevent oxidative stress by stimulating antioxidative systems in rats fed a high fat-high cholesterol diet.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.6
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• pp.969-974
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• 2013

In this study, liquid calcium was used to develop a calcium-fortified soy sauce-based seasoning for meat and the quality characteristics of the seasoning and cooked meat were investigated. All seasonings with different amount of liquid calcium (0, 2, 4, or 8%) showed no significant changes in pH and titratable acidity at $4^{\circ}C$ for 9 days; however, the control seasoning and seasoning with 2% liquid calcium (Ca-2%) showed significant decreases in pH and increases in titratable acidity during storage at $20^{\circ}C$ for 9 days, compared to the seasoning with 4% (Ca-4%) and 8% (Ca-8%) liquid calcium. We also observed that during storage at $20^{\circ}C$, the numbers of total aerobic bacteria, lactic acid bacteria, and yeast were significantly lower in Ca-4% and Ca-8% seasoning compared to the control or Ca-2%. The calcium contents in cooked meat seasoned with the control, Ca-2%, Ca-4%, or Ca-8% were 2.16, 33.47, 54.72, and 58.23 mg/100 g, respectively. Sensory evaluations demonstrated no significant differences in flavor, taste, juiciness, texture, and overall acceptability between the cooked meat samples. These results suggest that soy sauce seasoning supplemented with liquid calcium (2~8%) effectively increases the calcium content in cooked meat without adversely affecting its taste, flavor, and juiciness. Thus, this type of calcium-fortified seasoning may be helpful in combating the lack of calcium in modern diets.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.6
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• pp.933-940
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• 2013

In this study, methyl esters with different saturated fatty acids (SFA) were prepared by urea fractionation to make an oil-in-water emulsion. Emulsion characteristics (emulsion stability and oxidative stability) of the methyl ester emulsion were then studied at different percentages of methyl ester saturation (5, 28, 39, 50, and 72%, termed ${\Sigma}$SFA5, ${\Sigma}$SFA28, ${\Sigma}$SFA39, ${\Sigma}$SFA50, and ${\Sigma}$SFA72, respectively). The stability of emulsions (ES) with different SFA content was 46.0 (${\Sigma}$SFA5), 39.5 (${\Sigma}$SFA28), 32.7 (${\Sigma}$SFA39), 32.6 (${\Sigma}$SFA50), and 27.3 (${\Sigma}$SFA72). Results from Turbiscan showed that creaming or clarification, based on the backscattering intensity, was more pronounced with increases in the saturation degree of the emulsion. These results implied that the emulsions with lower saturation were more stable. During 30 days of storage, the lipid peroxide value increased for all emulsions, with the increase less pronounced with the increasing saturation of the emulsion; 1.880 (${\Sigma}$ SFA5), 1.267 (${\Sigma}$SFA28), 1.062 (${\Sigma}$SFA39), 0.342 (${\Sigma}$SFA50) and 0.153 (${\Sigma}$SFA72) mg $H_2O_2/mL$ emulsion. In addition, thiobarbituric acid reactive substances (TBARS) values were significantly lower in emulsions with high saturation (4.419 mg for ${\Sigma}$SFA50 and 4.226 mg for ${\Sigma}$SFA72) than emulsions with low saturation (6.229 mg for ${\Sigma}$SFA5, 6.801 mg for ${\Sigma}$SFA28 and 6.246 mg for ${\Sigma}$SFA39). In conclusion, the emulsions with a higher saturation degree of methyl esters showed lower emulsion stability but better oxidation stability.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.6
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• pp.819-827
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• 2016

This study was carried out to investigate anti-inflammatory, anti-diabetic, alcohol metabolizing, and hepatoprotective effects of hot water (MOW) and 80% ethanol (MOE) extracts from moringa (Moringa oleifera Lam.) leaf. The total phenol content of MOW and MOE were 45.49 and 63.06 mg tannic acid equivalents/g, respectively. 1,1-Diphenyl-2-picrylhydrazyl radical scavenging activities of MOW and MOE were remarkably elevated in a dose-dependent manner, and about 60.8% and 71.3% at 1 mg/mL, respectively (P<0.01). Superoxide dismutase-like activities of MOW and MOE were 2.8% and 7.4% at 5 mg/mL, respectively (P<0.05). ${\alpha}-Glucosidase$ inhibitory activity also increased in a dose-dependent manner in both extracts, and MOE was higher about two times than MOW at 5 mg/mL (P<0.001). The effects of MOW and MOE on alcohol metabolizing activity were determined by measuring generation of reduced nicotinamide adenine dinucleotide (NADH) by alcohol dehydrogenase (ADH) and acetaldehyde dehydrogenase (ALDH). ADH and ALDH activities significantly increased upon addition of MOW and MOE (P<0.05). Anti-inflammatory activity was examined in lipopolysaccharide-stimulated RAW 264.7 cells. Nitric oxide production was reduced to 32.1% and 81.2% by addition of MOW and MOE at 1 mg/mL, respectively (P<0.05). MOW and MOE showed significant protective effects against tacrine-induced cytotoxicity in Hep3B cells at $100{\mu}g/mL$. These results suggest that moringa leaf extracts have great potential as natural health products.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.6
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• pp.791-800
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• 2006

This study examined the effects of gromwell (Lithospermum erythrorhizon) extracts on the storage characteristics of Kangjung. At an increase of $0{\sim}0.25%$, there was no significant difference in the moisture content of wild and cultivated gromwell extract added to Kangjung, whereas there was a significant difference when increased to 0.5%. When compared, the occurrence of lipid oxidation among the controlled gromwell extract group stored at $60^{\circ}C$, resulted in peroxide values exceeding 40 meq/kg which is a maximum value for Hankwa within 12 hours of storage. However, at an increase of 0.25%, the cultivated gromwell extract added group reached limits within 16 hours. Furthermore, at a 0.5% increase in cultivated gromwell and 0.25% in wild gromwell, extract added groups exceeded this limit within 20 hours of storage. Gromwell added Kangjung, a fried food, showed efficiency in suppressing oxidation of fat, more so in the wild gromwell than the cultivated gromwell. In addition, efficiency in suppressing oxidation of fat increased at the 0.5% level than the 0.25% level. In conclusion, it is believed that an unused pigment resource called Lithospermum erythrorhizon, normally reserved for medicinal use, can be distributed as a safe food additive. In addition, as Lithospermum erythrorhizon is a natural antioxidant in fried foods, we believe this satisfies the demand for natural food.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.1
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• pp.46-49
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• 1999

Our previous studies have demonstrated the biological effects of alginic acid as a brown algae (Undasia pinnatisda) component on inhibitory action of obesity using animal model. This study was designed to investigate the effect of brown algae (BA)-noodles ($10\%,\;20\%$ and $40\%$) on inhibitory action of obesity in Sprague-Dawley (SD) male rats for 4 weeks. Body weight gain in SD rats for 4 weeks resulted in a marked inhibition ($7\%,\;17\%\;38\%$, respectively) by administration of $10\%,\;20\%$ and $40\%$ BA-noodles compared with control group. Total energy intake and feed efficiency in SD rats for 4 weeks resulted in a marked inhibition ($6\%,\;16\%\;37\%$ and $10\%\;20\%\;40\%$, respectively) by administration of $10\%\;20\%$ and $40\%$ BA-noodles compared with control group, but gross efficiency was not observed in these BA-noodle groups. Rohrer index and TM index as an obesity markers in SD rats for 4 weeks significantly decreased ($10\%\;15\%$ and $22\%$, respectively) by administration of $10\%,\;20\%$ and $40\%$ BA-noodles compared with control group. These results suggest that inhibitory effect of obesity in SD rats for 4 weeks may be due to decreases of body fat content resulted in a decrease of feed efficiency and energy intake by these BA-noodles.

• Korean Journal of Poultry Science
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• v.35 no.2
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• pp.153-162
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• 2008

This experiment was conducted to evaluate the dietary effects of mixture of probiotics and colistin on laying performance, intestinal microflora and egg yolk cholesterol in laying hens. One hundred sixty 50-wk-old Hy-Line Brown layers were divided into four treatments and fed a commercial diet (Control) or experimental diets containing 0.2% mixture of probiotics or probiotics and colistin mixture (T1, Bacillus subtilis + Aspergillus oryzae + Lactobacillus plantarum; T2, Bacillus subtilis + Aspergillus oryzae; T3, Bacillus subtilis + Aspergillus oryzae+colistin) for 8 wk. No significant differences were found in laying performance and liver weight among the groups. The Haugh unit of treated groups were significantly improved (P<0.05) compared to that of control, but eggshell qualities were not changed by the treatments. The cecal ammonia concentration was significantly decreased in both T1 and T3 groups. The number of coli forms in cecal content and feces were significantly reduced in all treated groups compared to that of Control (P<0.05). The egg yolk cholesterol contents in the groups fed the diet containing mixture of probiotics and colistin were reduced in comparison with that of Control. In conclusion, dietary supplementation of mixture of probiotics and colistin improved quality of egg albumen, and reduced the egg cholesterol contents. They also reduced intestinal coli forms without harmful effects on overall productive and physiological responses in laying hens.