• Microbiology and Biotechnology Letters
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• v.26 no.2
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• pp.143-150
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• 1998

Many enzymes catalyze a primary reaction and/or secondary reaction. Dextransucrase usually synthesize dextran from sucrose as a primary reaction. The secondary reaction of dextransucrase is the transfer of glucose from sucrose to carbohydrate accepters. We have reacted dextransucrase from Leuconostoc mesenteroides B-742CB with sucrose and starches; granule or gelatinized starches, and Small or Potato starches. The yield of modified starch was ranged from 46% to 72%(s.d.<${pm}$5%) of theoretical depends on various reaction conditions. Modified products were more resistant against the hydrolysis of ${alpha}$-amylase, isoamylase, pullulanase and endo-dextranase than those of native starch. Based on the reactions from enzyme hydrolysis and methylation followed by acid hydrolysis modification of granule starch was more efficient than the modification of gelatinized starch. After modification of granule starch with dextransucrase, there produced a soluble modified starch. After modification the starch granules were fractionated to small size. The positions of glucose substitution of the modified products were determined by methylation followed by acid hydrolysis and analyzed by TLC. The products were modified by the addition of glucose to the position of C3, C4 and C6 free hydroxyl group of glucose residues in the starch.

• Horticultural Science & Technology
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• v.28 no.4
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• pp.561-566
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• 2010

The effects of calcium concentrations of coating bag treatment to reduce berry cracking were investigated through the changes of pericarp structure and berry cracking rate in 'Kyoho' grape. The soluble solids and anthocyanin contents in harvested grapes were highest at $18.1^{\circ}Brix$ and $2.56{\mu}g{\cdot}cm^{-2}$ in non bagging group compared with those of calcium coating bag treatments. The firmness of pericarp was lowest in non bagging group ($1.18kg{\cdot}5mm^{-1}{\O}$) compared with bagging treatments (1.23, 1.24, 1.27, $1.35kg{\cdot}5mm^{-1}{\O}$) which increased effectively in proportion to calcium concentration. As a result of histological observation of the fruit skin, the bagging with higher calcium concentration developed thicker epidermal and sub-epidermal layer of cell wall than that of non bagging. Moreover, the strengthened berry skin of calcium treatments effectively decreased berry cracking rate under critical turgor pressure. However, the 9% calcium coating bag treatment which was the most effective for cracking reduction seriously decreased marketability of harvested grape with white color staining on berry skin caused by eluted calcium from the coated paper bag. Based on our results, we recommend that 6% calcium coating bag be available for berry cracking reduction and higher quality production.

• Journal of the Korean Wood Science and Technology
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• v.45 no.5
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• pp.495-510
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• 2017

This study was to investigate the antioxidant activities of Cryptomeria japonica leaves extracts such as essential oil, methanol extract and hot water extract and to evaluate its potential as a natural antioxidant. Antioxidant activities of extracts were evaluated by DPPH radical scavenging activity, FRAP activity, zanthin oxidase inhibitory activity, and iron ion chelate activity, comparing with the positive controls. According to the results, methanol and hot water extracts showed higher antioxidant activities than essential oil. This fact suggested that terpenoids have lower antioxidant effect than phenolic compounds which were found in methanol and hot water extracts. Especially, acetone and water soluble fractions of methanol extract and ethanol fraction of hot water extract contained a lot of phenolic compounds and hydroxyl group, indicating that many hydroxyl groups and glycosidic bonds showed higher antioxidant effect than the other fractions. These results can suggest that the phenolic compounds which contained hydroxyl group or glycosidic bonds have a certain role for effective antioxidant activities.

• Korean Journal of Food Science and Technology
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• v.49 no.6
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• pp.625-631
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• 2017

This study was performed to examine the quality characteristics and antioxidant activity of curd yogurt with varying content (0.5-2% (w/w)) of lemon grass hot-water extract (LGHWE). The pH decreased with higher LGHWE content until 8 h, with the treated groups showing higher pH values than the control group after 12 h. The viscosity and the viable cell counts of the yogurt with 2% LGHWE were significantly lower than those of the control group during fermentation. Color values of LGHWE yogurt were lower in terms of brightness, whereas redness and yellowness values were higher compared to the control. The DPPH radical scavenging activity and soluble content significantly increased with higher LGHWE content. Consumer acceptability score of yogurt with 0.5% LGHWE was ranked higher than that of other yogurts. Yogurt containing 0.5% LGHWE showed no differences in pH and titratable acidity compared to control after storage at $4^{\circ}C$ for 14 days.

• Korean journal of applied entomology
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• v.35 no.3
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• pp.254-259
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• 1996

The biochemical factors responsible for parathion resistance in a ethyl fenitrothion-selected Yumenoshima I11 (EF-30) strain of the housefly were examined. Great difference (167-fold) in the Iso was observed between the resistant EF-30 (R) and susceptible SRS (S) strains in vitro, suggesting that altered acetylcholinesterase (AChE) in the housefly strain was an important factor in the resistance. The in vitro degradative activity of parathion and paraoxon in both strains was associated with the microsomal and soluble fractions and required NADPH and reduced glutahione (GSH), respectively. The R strain possessed higher activity for GSH S-transferase than the S strain, and this enzyme appears to be important in the resistance mechanism. The R strain was highly resistant to parathion (101,487-fold), but substitution of the methoxy group for ethoxy group decreased the resistance level (25,914-fold) and parathion could be a substrate of GSH S-transferase. It is concluded that the combination of some factors (altered AChE, and enhanced activity of cytochrome P450 dependent monooxygenase and GSH S-transferase) could be sufficient to account for the extremely high level of resistance to parathion and parathion-methyl, although a possible involvement of other factor(s) can not be excluded.

• Journal of Nutrition and Health
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• v.34 no.3
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• pp.285-298
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• 2001

The effects of dried leaf powders and water and ethanol extracts of persimmon and green tea on lipid metabolism, lipid peroxidation and antioxidative enzyme activity were investigated in 12-month-old rats. Forty-nine male Sprague-Dawley rats weighing 520$\pm$19g were blocked into seven groups according to body weight. Rats were raised for four weeks with control(no tea leaf powder or extracts) and experimental diets containing either 5%(w/w) dried leaf powders of persimmon(Diospyros kaki Thunb) or green tea(Camellia sinensis O. Ktze), or water or ethanol extract from equal amounts of each dried tea powder. Food intakes of all tea diet groups were higher than that of control. Weight gains and food efficiency ratios of all tea diet groups were not significantly different from those of control. All tea diets decreased plasma triglyceride level, especially, green tea powder and persimmon ethanol diets were more effective than other diet. All the tea diet groups showed decrease in liver triglyceride level, and persimmon powder and ethanol extract increased fecal triglyceride excretion. Plasma cholesterol levels of all the tea diet groups were not significantly different from the control, but control. Fecal cholesterliver cholesterol concegroups were significantlntrations of all tea y lower than that of ol excretions of persimmon powder, green tea ethanol extract, persommon ethanol extract and green tea ethanol extract groups were significantly higher than that of control. Plasma and liver thiobarbituric acid reactive substance(TBARS) concentrations of all the tea diet groups were lower than that of control. Especially, plasma TBARS concentrations of green tea powder and persimmon ethanol extract groups were sinificantly low. Red blood cell(RBC) superoxide dismutase(SOD) activities of persimmon ethanol extract and green tea water extract groups were increased, and RBC catalase activities of all experimental groups were not significantly different. RBC glutathione peroxidase(GSH-px) activities of persimmon ethanol extract, persimmon water extract and green tea powder groups were increased. Liver SOD activities of all the tea diet groups except green tea ethanol extract group were higher than that of control. Liver catalase activities of all experimental groups were not significantly different, and liver GSH-px activity of green tea powder group was significantly higher than that of control. In conclusion, dried leaf powders, and water and ethanol extracts of persimmon and green tea were effective in lowering lipid level, inhibiting lipid peroxidation and increasing antioxdative enzyme activities in 12-month-old rat. Green tea leaf powder with high contents of flavonoids and water soluble dietar fiber was most effective in lowering plasma triglyceride, cholesterol and TBARS level. (Korean J Nutrition 34(3) : 285~298, 2001)

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.1
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• pp.10-16
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• 1997

To confirm the possibility of seaweed extracts for functional food, water or ethyl alcohol solubles were extracted from laver, Porphyra yezoensis and evaluated those food components such as proteins, carbohydrates, nucleic acids, taurine, pigments and browning extent. The amount of proteins, polysaccharides and nucleic acids extracted decreased with increasing ethyl alcohol concentration, which was maximal when water was used as extraction solvent. The extractability of proteins, polysaccharides and nucleic acids was different between the dried and the roasted laver. Taurine was extracted about 1% from the dried and the roasted laver in the range of o~7o% ethyl alcohol concentration. The amount of carotenoids extracted by 95% ethyl alcohol from the dried and the roasted laver were 146.6 and 138.4mg%, respectively, which was 66 ~ 80% of yield extracted by methanol/acetone(1/1) solvent. The browning value of 50 ~6o% ethyl alcohol extraction group from roasted laver was highest among water/ethyl alcohol extraction group. The extraction yield was maximum when laver was extracted with water, and the value was 26.3% for the dried laver and 27.5% for the roasted layer. Organoleptic characteristics from four kinds of extraction groups containing hot water extraction showed that extracts from the roasted laver were evaluated most eminent and thought to be applicable to various preparation of food.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.7
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• pp.1042-1047
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• 2014

This study examined the quality characteristics of Yanggaeng added with tomato powder (0, 5, 10, 15, and 20%) and oligosaccharides instead of red beans and sugar. The moisture content of tomato Yanggaeng was 45.89~33.64% and was highest in the control group. The pH ranged 3.96~6.24 and significant decreased with the addition of tomato powder. Hunter's color value, lightness (L value) were the highest in Yanggaeng added with 20% tomato powder. Redness (a value) increased with tomato powder content, except for 20% tomato powder. Yellowness (b value) significantly increased with tomato powder content (P<0.05) but decreased with 20% tomato powder. In the texture profile analysis, hardness, cohesiveness, gumminess, and chewiness significantly decreased (P<0.05) with the addition of tomato powder. Total soluble solid content ($^{\circ}Brix$) was the highest (5.16) in the control group, whereas that of tomato Yanggaeng ranged 4.46~4.92 and significantly decreased (P<0.05) with the addition of tomato powder. The antioxidative activity based on 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity of Yanggaeng increased with the concentration of tomato powder, although those of Yanggaeng added with 15% and 20% tomato powder were not significantly different (P<0.05). Yanggaeng added with 5 and 10% tomato powder showed acceptable sensory properties, including color, flavor, sweet taste, sour taste, and overall quality. In terms of sensory evaluation and antioxidant activity, the results show that Yanggaeng added with 10% tomato powder was the best, but more research should be conducted in order to improve sensory acceptability.

• Food Science and Preservation
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• v.19 no.5
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• pp.645-651
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• 2012

The food functional properties of Pleurotus eryngii cultivated with different wavelengths of light-emitting diode (LED) light were analyzed in this study. The levels of total soluble solids of Pleurotus eryngii increased with all the LED lights, except mixed LED light ($B^*R$, $B^*G$ and $R^*G$). Thirty one kinds of components were detected by analyzing the free amino acids. The total free amino acid contents had a slightly higher tendency in the control group, but the ratios of eight essential amino acids among the total amino acids of Pleurotus eryngii cultivated under all the LED lights, including the blue light (blue, $B^*R$, $B^*G$ and $B^*R^*G^*U$) and the green light, were higher than that in the control group. K was the highest-content of mineral, and Mn was the lowest-content. The Ca content increased through cultivation under all the LED lights, except the blue light, but the Fe content (under the green and $B^*R$ lights), K content (under the red and UV-A lights) and Mg content (under the $R^*G$, UV-A and red lights) increased under the exclusive LED light. The total phenolic compounds increased by cultivation under all the LED lights, except the UV-A and mixed lights ($R^*G$ and $B^*R^*G^*U$). The DPPH radical scavenging activity was also improved by all the LED lights, except the mixed light ($R^*G$).

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.5
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• pp.635-641
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• 2011

Anti-atherogenic effects in tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$)-stimulated human umbilical vein endothelial cells (HUVEC) are involved with suppressed oxidative stress, cell adhesion molecules, and pro-inflammatory factors. The aim of this study was to determine whether green tea seed coat ethyl acetate fraction (GTSCE) could modulate cell adhesion molecules and inflammatory mediators in HUVEC stimulated with TNF-${\alpha}$. Nitric oxide (NO) production was significantly increased in TNF-${\alpha}$-stimulated HUVEC compared to TNF-${\alpha}$ only treated cells. The NO that is produced by endothelial nitric oxide synthase dilates blood vessels and has protective effects against platelet and leucocyte adhesion. GTSCE at 25, 50, 75, and $100\;{\mu}g$/mL significantly (p<0.05) reduced TNF-${\alpha}$ production. GTSCE significantly (p<0.05) inhibited soluble vascular cell adhesion molecule-1 level, in a dose-dependent manner. Monocyte chemoattractant protein-1 level was also significantly (p<0.05) inhibited by GTSCE treatment at $75\;{\mu}g$/mL compared to the TNF-${\alpha}$-only treated group. Total antioxidant capacity by GTSCE was significantly (p<0.05) enhanced compared to the TNF-${\alpha}$-only treated group. These results suggest that GTSCE can inhibit the production of cell adhesion molecules and inflammatory mediators and could be used as a candidate bioactive material to prevent the development of atherosclerosis.