• Korean Journal of Food Science and Technology
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• v.50 no.1
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• pp.111-116
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• 2018

Roasting process of grains modifies their physicochemical characteristics that affect flavor, color, taste, and textures, as well as composition of bioactive compounds. We roasted oats at different temperatures (150, 200, and $250^{\circ}C$) and for different time periods (15 and 30 min). The polyphenol and flavonoid contents in different solvent extracts (methanol, fermented ethanol, and water) were also investigated. The total polyphenol and flavonoid contents were highest in the methanolic extract (135 mg gallic acid equivalent/g and 29 mg catechin equivalent/g, respectively, at $250^{\circ}C/30min$ roasting) and increased with roasting time and temperature. In addition, the avenanthramides were most abundant as accessed ($266{\mu}g/g$) in the methanolic extract upon roasting at $200^{\circ}C$ for 15 min. The radical scavenging activities, using 2,2-diphenyl-1-picrylhydrazyl and 2,2'-azino-bis-3-ethylbenzothiazoline-6-sulphonic acid scavenging, increased with roasting temperature and time. The roasting process may modify the physicochemical structure of oats, thereby, improving polyphenol extraction and antioxidant activity. The results of this study could be used for the manufacture of foods using roasted oats.

• Korean Journal of Food Science and Technology
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• v.33 no.5
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• pp.611-618
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• 2001

The ethanol extract of Dryopteris crassirhizoma Nakai showed strong growth inhibition against 5 strains of Listeria monocytogenes at the concentrations of $100{\sim}500$ ppm and the minimum inhibitory concentration of n-hexane fraction was under 50 ppm. The D8-2-5 fraction isolated from n-hexane fraction of Dryopteris crassirhizoma Nakai showed a strong bactericidal activity on 5 strains of L. monocytogenes at 20 ppm level in tryptic soy broth medium. At the level, the viable count was reduced $4{\sim}6$ log cycle compared to initial cell number. Observation by the measurement of adenosine triphosphate (ATP) contents and transmission electron microscope showed that disruptions of the cell wall and elution of intracellular ATP are assumed to be due to the bactericidal activity. In addition, the n-hexane fraction of Dryopteris crassirhizoma Nakai showed the strong growth inhibitions at 50 ppm on Vibrio parahaemolyticus and Bacillus cereus, and at 25 ppm on Staphylococcus aureus.

• Korean Journal of Food Science and Technology
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• v.34 no.6
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• pp.1091-1097
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• 2002

In order to improve palatability and quality of traditional kochujang, kiwifruit (Actinidia deliciosa) was added to traditional kochujang fermented for 3 months. Physicochemical and microbial characteristics were investigated during fermentation at $30^{\circ}C$. Moisture contents of all treated kochujangs increased with increasing amount of kiwifruit added during fermentation. pH of kiwifruit-added kochujang was lower than that of the control kochujang, whereas no significant differences in titratible acidity was observed among all treatments. Crude protein and salt contents of kiwifruit-added kochujang were lower than those of the control, whereas no difference in crude fat contents were found. Ethanol and amino-nitrogen contents of 6 and 9% kiwifruit-added kochujang were higher than those of the control. Fructose contents of kiwi-added kochujangs were higher than that of the control. Major organic acids of kochujang were in the order of malic acid > citric acid > succinic acid > acetic acid > lactic acid > oxalic acid. Succinic acid level increased significantly during fermentation and was higher in kiwifruit-added kochujang than in the control. Bacterial cell counts of all treatments were not different, and viable cell count of yeast was slightly higher in kiwifruit-added kochujang only at the initial fermentation period. Sensory evaluation revealed that the addition of 9% kiwifruit was the optimum condition for improving kochujang quality.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.6
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• pp.951-957
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• 2004

Hypoglycemic effect of Prunus mume (PM) extract containing in Sangjinyangheul-tang and Hwangkeumtang, one of the diabetic herbal medicines, was determined by investigating insulin-like action, insulin sensitizing action and a-glucoamylase suppressing action. Insulin-like activity of 3T3-L1 fibroblast was not shown with the treatment of PM methanol extracts. However, treatment with 20% or 40% PM methanol extracts and differentiation inducers significantly decreased the differentiation of 3T3-L1 fibroblasts to adipocytes. A significant insulin sensitizing activity was observed in 3T3-L1 adipocytes, giving PM extracts (60%, 80% and 100%) with 1 ng/mL insulin to reach glucose uptake level increased by 50 ng/mL of insulin alone. In addition, 20% and 40% methanol extracts of PM suppressed the a-glucoamylase activity by 30% in vitro. However, there was no significant differences in the peak of serum glucose levels and area under the curve in Sprague Dawley male rats treated with PM ethanol extract or cellulose and 2 g maltose or dextrin/kg body weight. These data suggested that PM extracts contain effective insulin sensitizing compounds, lipid synthesis suppressing compounds and possibly a-glucoamylase suppressing compounds. Therefore, PM extracts are beneficial for anti-diabetic treatment in obese diabetic patients.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.9
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• pp.1232-1236
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• 2006

Crude polysaccharide fractions of commercially available grape wines (red wine, white wine and wild grape wine) were prepared by evaporation and ethanol precipitation to confirm and identify anti complementary polysaccharides in the wines. When these fractions were evaluated for their anti complementary activity, crude polysaccharide fractions of red wine (RW-0) and wild grape wine (WGW-0) showed higher anti-complementary activities than those of white wine (WW-0). RW-0 and WW-0 were further fractionated into RW-1, WW-1 as high-molecular fractions, and RW-2, WW-2 as low-molecular fractions through gel permeation column chromatography on Sephadex G-75. RW-1 had the most potent activity with the highest carbohydrate content (91.3%). Anti-complementary activity of red wine was higher than that of white wine, suggesting that active polysaccharides such as pectin and hemicellulose are mainly distributed in the grape skin which is removed during white wine making. In addition, high molecular fractions, RW-1 and WW-1 with high contents of carbohydrate and high yields showed higher activities than those of low molecular fractions, RW-2 and WW-2.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.9
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• pp.1146-1150
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• 2006

In the present study, the Lycium chinensis Miller was harvested at intervals of one month in order to distinguish outstanding species and to determine optimal harvest time. From these harvests, extracts were prepared from ethanol. The total usable sugar, betaine, and phenolic acid contents as well as electron donating ability and SOD liked activity of the extracts were then measured. While sugar content of the Lycium chinensis Miller showed no significant difference among the various species examined, usable sugar content of the crop harvested in November was higher than that of the crop harvested in August. The Lycium chinensis Miller was picked in August, September, October, and November and analyzed for betaine content. According to this analysis, betaine content was higher in the crop harvested in November than in that harvested in August. In particular, considerable difference in betaine content per species or harvest time was exhibited. The SOD-liked activity in all of the Lycium chinensis Miller extracts showed an alleviation effect of at least 90%. In addition, there was no significant difference according to either species or harvest time. On the other hand, SOD liked activity was higher in November than in August.

• Journal of agriculture & life science
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• v.45 no.6
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• pp.183-191
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• 2011

We investigated characterization as cosmetic substances of chestnut inner skin extracts with in vitro antioxidant activity. Total phenolics of various extracts from chestnut inner skin were the highest 60% methanol (164.82 mg/g), and ethyl acetate fractions (191.14 mg/g). We found that the both samples from chestnut inner skin dose-dependently increased in vitro antioxidant activities (DPPH radical scavenging activity and inhibition of lipid peroxidation). In addition, the both samples also showed a strong UV absorption in the range of UV-B (290-320 nm). Especially the 60% ethanol extracts presented higher inhibitory effect on elastase (46.40% at $100{\mu}g/mL$) than that of the ethyl acetate fractions, so that it showed in vitro anti-wrinkle activity. Finally, the 60% methanol extracts and ethyl acetate fractions showed anti-bacterial activity against skin pathogenic bacteria. Consequently, these results suggest that the chestnut inner skin can be used for cosmetic industry.

• Food Engineering Progress
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• v.13 no.2
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• pp.138-146
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• 2009

The crude polysaccharide fraction from fruit body of Auricularia auricula were obtained by using hot water extraction and ethanol precipitation. As the crude polysaccharide fraction contained the brownish dark colored compounds, the adsorption study of pigments from the crude polysaccharide using activated carbon was carried out. The pigment compounds showed an absorption characteristic with $\lambda_{max}$ of 230 nm and the absorbance at 230 nm was taken as color intensity. Adsorption capacity of pigment depended on increase of the activated carbon to sample loading ratio. The adsorption capacity increased with increase of pH and temperature in the pH range of 3.0-7.0 and temperature range of 25-40$^{\circ}C$, but decreased in the temperature range of 40-70$^{\circ}C$. The optimum capacity was obtained at addition of 16.7 mg activated carbon per mL sample solution (concentration = 3 mg/mL) at pH of 7.0 and temperature of 40$^{\circ}C$. Treatment for 10 min was sufficient to achieve the 80% decolorization and 1.25 fold purification of polysaccharide. Langmuir isotherm and pseudo second-order kinetic model provided the best fitting for adsorption of the brownish dark colored compounds onto powdered active carbon. The activation energies of adsorption from the Langmuir isotherm parameter in the ranges of 25-40$^{\circ}C$ and 40-70$^{\circ}C$ was -2.54 and 4.38 kcal/g, respectively. The results of low activation energy also indicated that the adsorption process was a physical adsorption which was controlled by diffnsion.

• Korean Chemical Engineering Research
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• v.57 no.6
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• pp.749-757
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• 2019

Methyltrimethoxysilane (MTMS) and trimethylethoxysilane (TMES) as starting materials were dissolved in various types of solvents, and hydrolysis with water and polycondensation reaction were carried out using various types of catalysts to prepare non-fluorinated water-repellent coating solutions. The coating solutions were spin-coated on cold-rolled steel sheets, and thermally cured to prepare water-repellent coating films. The effect of types of catalysts and solvents on the water repellency of the resulting coating films was investigated during this process. When hydrochloric acid and nitric acid, which are strong acids, were used as catalysts, the solutions showed a white opaque state due to the aggregation of siloxane polymers. On the other hand, when acetic acid, phosphoric acid, and oxalic acid, which are weak acids, were used, they were in a stable and transparent state without precipitation. As a result, the contact angles of the coated films, prepared from hydrochloric acid and nitric acid, were $58^{\circ}$ and $92^{\circ}$, respectively, showing low water repellency. On the other hand, when acetic acid, phosphoric acid, and oxalic acid were used, the contact angles of the coated films were $101^{\circ}$, $103^{\circ}$ and $116^{\circ}$, respectively, showing high water repellency. In addition, when isopropanol and ethanol were used as solvents, phase separation occurred in the solutions due to the aggregation of siloxane polymers. On the other hand, when methanol, ethyl acetate, and methyl ethyl ketone were used as solvents, the solutions were transparent and showed a stable state without sedimentation.

• Korean Journal of Plant Resources
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• v.32 no.5
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• pp.415-422
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• 2019

Rhodosporidium toruloides has been known as an in vitro model of fat metabolism. The purpose of this study is to identify the triglyceride inhibitory effects of hot water extracts from beetroot using R. toruloides. The triglyceride content of oleaginous yeast cultured from YPD culture medium were regulated by treatment of beet root hot water and ethanol extract, respectively. In addition, the number of cells in the oleaginous yeast was 10.48, 8.46, 12.40, 12.80 and $8.24{\times}10^3cell/mL$. The treatment of hot water extract of beet root increased total lipid content of oleaginous yeast in dose dependently. Moreover, the triglyceride content of oleaginous yeast was decreased by hot water extract of beet root extract, respectively. The fat droplet in the oleaginous yeast decreased according to the concentration of hot water extracts from beetroot. The ratio of increase in the number of cells in the oleaginous yeast were increased dose-dependently by treatment of hot water extract from beetroot compared with control group. The free fatty acid and total carotenoid contents were increased concentration-dependently by treatment of hot water extracts from beetroot. These study results indicate that hot water extracts from beetroot has a triglyceride inhibitory effects.