• Korean Journal of Food Science and Technology
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• v.38 no.4
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• pp.554-561
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• 2006

The objective of this study was to investigate the effects of browning inhibitors during fermentation and storage of rice-grape wine. Bentonite, polyvinylopolypyrrolidone (PVPP), and potassium metabisulfite were added to rice-grape wine during fermentation and storage in order to find an effective method of inhibiting browning. Total phenolics content, pH, amino acidity, hydroxymethylfurfural content, and absorbance at 420 nm were measured during storage to assess the effects of the different browning substrates. Potassium metabisulfite was the most effective browning inhibitior. Sensory evaluation also showed that rice-grape wine treated with potassium metabisulfite was highly Preferable in terms of color, taste, flavor, and overall quality.

• Korean Journal of Agricultural Science
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• v.21 no.2
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• pp.81-91
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• 1994

This study was conducted to find a potential effect of ethephon or dichlorprop spray on the fruit growth and maturation in 'Niitaka' pears. Chemicals were applied between June 10 to 24 (7-9 weeks after full bloom). Ethephon in the range from 25 ppm to 100 ppm, and dichlorprop from 20 ppm to 40 ppm reduced the fruit size regardless application time and concentration. The fruit growth was more inhibited at the higher concentrations in both chemicals. Flesh firmness was more rapidly decreased in the fruit treated by both chemicals. Firmness at harvest was lowest in the treatment of 100 ppm ethephon. The climacteric increase of ethylene synthesis occurred earlier in the fruit treated by ethephon or dichlorprop regardless application concentrations and the maximum peak of ethylene production was rugher. Total phenolics significantly reduced in fruits treated with ethephon. However, the contents of soluble solids and acid were not affected by ethephon or dichlorprop treatment. Ground color was changed rapidlys by the treatments resulting in the early maturation of fruit. Optimum maturity of fruit was shortened 2-3 days by ethephon and 3-4 days by dichlorporp when maturity was determined on the basis of ground color development and firmness.

• Journal of the Korean Wood Science and Technology
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• v.33 no.6 s.134
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• pp.79-86
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• 2005

Aspen wood (Populus tremuloides, L.) was biotreated with Ceriporiopsis subvermispora for 1, 2, 4, and 6 weeks to observe the physical/chemical modification of wood components. Milled wood lignins (MWLs) isolated from each decayed wood were analyzed by gel permeation chromatography (GPC) and nitrobenzene oxidation (NBO). As fungal treatment was progressed, lignin contents continuously decreased up to 20% after 6-week treatment. The lignin polymer could be fragmented to low-molecular phenolics, which make an enhancement of alkali solubility. Holocellulose contents were not affected severely during the period of fungal treatment, only reduction of 5~6% compared to the control. Xylose contents were decreased gradually from 23.4% to 18% after 6 weeks, whereas alpha-cellulose remained almost unchanged. Gel permeation chromatography (GPC) indicates that molecular weight of lignin undergoes a slight decrement for 4 weeks of fungal treatment. Nitrobenzene oxidation revealed that total yield of NBO products of lignins were lowered ca 20% after fungal treatment. Sum of syringaldehyde and syringic acid are remarkably decreased. However, increment of sum of vanillin and vanillic acid was surprisingly observed. These results work as indirect evidence that a specific lignolytic reaction, maybe selective demethoxylaytion of S-lignin, can occur during fungal treatment of aspen wood by C. subvermispora.

• Korean Journal of Food Science and Technology
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• v.50 no.2
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• pp.132-137
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• 2018

Enzymatic treatments of maize flour (MF) were investigated using commercial carbohydrases (Ultraflo L and Pentopan 500 BG) to enhance the phenolic acid content and antioxidant property. The total phenolic acid content of the MF was 3.76 mg/100 g, whereas those of the Pentopan 500 BG and Ultraflo L treated MF were 6.85 and 39.55 mg/100 g, respectively. Particularly, ferulic acid content of Pentopan 500 BG-treated MF was 20.0 times higher than that of untreated MF (1.7 vs. 33.9 mg/100 g). Pentopan 500 BG appeared to be more effective than Ultraflo L in increasing the free phenolic acid content. Antioxidant activities of enzyme treated MF were significantly higher than untreated MF. In particular, the Pentopan 500 BG-treated MF (16.0 mmol TE/100 g) was approximately 1.5 times higher than untreated MF (12.6 mmol TE/100 g). Enzymatic hydrolysis of cell wall polysaccharides in MF could be used as an effective procedure for not only increasing phenolic content but also antioxidant activities.

• Korean Journal of Food Science and Technology
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• v.47 no.4
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• pp.460-467
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• 2015

Sea urchin roe obtained from Anthocidaris crassispina and Pseudocentrotus depressus was briefly salt-fermented (5%), followed by ethanol treatment (1%) and the physicochemical properties as well as antioxidant activity were investigated. Compared to raw sea urchin roes, the salted one showed a significantly low amount of water (p<0.001) high salinity (p<0.05), ash content (p<0.001) and Na content (p<0.001). With salt-fermentation, the redness (p<0.05) and yellowness (p<0.001) of roe decreased noticeably, indicating the decomposition of endogenous carotenoids. Accordingly, the salted roe showed a lower DPPH radical scavenging activity than its unsalted counterpart. Additionally, it showed a significantly lower metal-chelating activity (p<0.05) and metal chelator content (e.g. ortho-phenolics) displayed by a negligible difference in titratable acidity. The salted roe showed significantly increased hardness (p<0.05) and total reducing capacity (p<0.001), which were attributed to the protein coagulation and the release of antioxidants bound to macromolecules after the ethanol treatment, respectively.

• Journal of Life Science
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• v.21 no.7
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• pp.976-984
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• 2011

Total phenolic content was the highest in 60% ethanol extracts at 21.91 mg/g, and inhibitory activity against tyrosinase of 60% ethanol extracts was higher than ethanol extracts of other concentration. The inhibitory compounds against tyrosinase from Persimmon leaves were purified using Sephadex LH-20, MCI-gel CHP-20 column chromatography with gradient elution. Two purified compounds were isolated as a result. The chemical structures of each compound were determined and identified using $^1H$-NMR and $^{13}C$-NMR, FAB-Mass. The compounds were confirmed as (+)-gallocatechin and prodelphinidin B-3. The tyrosinase inhibitory activities of purified (+)-gallocatechin and prodelphinidin B-3 were 29.5 and 40.2%, respectively. The inhibitory activities of (+)-gallocatechin and prodelphinidin B-3 against melanin biosynthesis in melanoma cell were 32.5 and 46.7%. The safety of essence with tyrosinase inhibitory compounds from persimmon leaves was also assessed by various safety profiles. First, changes in pH (4.90~4.95) and viscosity (23,000~26,000 cP) was not detected for 60 days. Essence also showed stability against temperature and light for 60 days. All these findings suggest that extracts from persimmon leaves have a great potential as a cosmetical ingredient with a potent whitening effect.

• Food Science and Preservation
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• v.19 no.5
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• pp.744-750
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• 2012

In this study, the optimal conditions for phenolic-compound extraction from medicinal plants were found to be 24 h and about 50% ethanol. The electron-donating scavenging activities (DPPH), ABTS radical-cation decolorization (ABTS), antioxidant protection factor (PF), and thiobarbituric acid reaction substance (TBAR) were measured to determine the antioxidant activities of the extracts of Sanguisorba officinalis Linn., Citrus unshiu Markovich, Melia azedarach L., Asparagus cochinchinensis Merr., Citrus unshiu S., Polygonum aviculare L., and Leonurus sibiricus L. The total phenolic contents of the extracts of medical plants were determined to be 0.45-3.00 mg/g in the water extracts and 0.33-3.15 mg/g in the 50% ethanol extracts. The electron-donating abilities (EDA) of the water and ethanol extracts were both above 85% at the $50{\mu}g/ml$ concentration. The ABTS radical-cation decolorization was above 80% at the $100{\mu}g/ml$ concentration in all the extracts of various medicinal plants. The antioxidant protection factor (PF) of the Melia azedarach L. extracts was found to be $1.65{\pm}0.40$ PF in the water extracts at the $100{\mu}g/ml$ concentration, and was higher than those of the other medicinal-plant extracts. The TBAR inhibition rates of all the medicinal-plant extracts, except Asparagus cochinchinensis Merr., were above 85% at the $100{\mu}g/ml$ concentration. These results confirmed that the various oriental medicinal plants (Sanguisorba officinalis Linn., Citrus unshiu Markovich, Melia azedarach L., Asparagus cochinchinensis Merr., Citrus unshiu S., Polygonum aviculare L., and Leonurus sibiricus L.) that were included in this study are useful functional-food sources.

• Korean Journal of Plant Resources
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• v.26 no.5
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• pp.539-547
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• 2013

This study investigates the change of chemical components, antioxidant and antimutagenic activity in Glycyrrhiza uralensis Fischer stems and leaves (GU) by the various processing methods, as follows: fresh (GU-1), dried under the shade (GU-2), blanched (GU-3), roasted 3 times (GU-4), roasted 4 times (GU-5). The components have been identified and quantified through the use of gas chromatograph-mass spectrometry (GC-MS). At results, cis-1,3-dimethyl-2-methylenecyclohexaneat at 19.7 min and n-hexadecanoic acid at 21.5 min were detected in five kinds of extract. 3-O-Methyl-D-fructose at 17.8 min was observed in four extracts except in GU-1 and aminopyrazine at 19.8min was observed in four extracts except in GU-4. The total phenolics contents was high in GU-4(3.38 g/100 g). ABTS radical scavenging was high in GU-5($EC_{50}$, 0.57 ug) and DPPH radical scavenging was high in GU-4($EC_{50}$, 2.66 ug). The extracts of GU-3, GU-4, and GU-2 were most potent in anti-mutagenicity activity against 1-NP, Trip-P-1, and Trip-P-2, respectively. GU-3 and GU-4 also showed most potent effect of anti-mutagenicity on 2-AA and AFB1, respectively.

• Food Science and Preservation
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• v.24 no.5
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• pp.673-679
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• 2017

In this study, the antimicrobial, antioxidant activities and ${\alpha}$-glucosidase inhibitory activities of Amphidinium carterae ethanol extract (AE) was evaluated for using as a functional food ingredient. Chlorella ethanol extract (CE) was used to the comparison as a control. Anticancer activities of the AE and CE were analyzed by HepG2 and HT-29 human cancer cell. The AE showed antimicrobial activities for all tested bacterial strains. Whereas, CE showed antimicrobial activities for several tested bacterial strains only. The CE showed higher total phenolics contents, DPPH and ABTS radical-scavenging activities (47.36 mg/g, 22.42% and 28.58%, respectively) than those of AE (8.88 mg/g, 20.16% and 17.69%, respectively). AE showed anti-diabetic effect on ${\alpha}$-glucosidase inhibitory activity with dose-dependantly manner. The cell viability of AE ($125{\mu}g/mL$) on HepG2 and HT-29 human cancer cells were 38.12% and 11.27%, respectively. It was demonstrated that ethanol was efficient solvent for extracting functional components from A. carterae. These results indicated that AE can be described as a good candidate for using as a functional food ingredient.

• Journal of Life Science
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• v.18 no.3
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• pp.403-408
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• 2008

In this study, we compared with 80% ethanol extracts from peel of Poncirus trifoliata (PTP) and peel of Citrus junos (CJP) against antioxidant and immune activities. Total phenolics and flavonoids contents in PTP extracts were $60.75{\pm}1.15$ and $33.75{\pm}0.15$ mg/l00 g, respectively, and those were lower than CJP extracts. Antioxidant activities of PTP were increased with the more concentration, and were similar to CJP. Antioxidant activities of PTP were increased with increasing of concentration, and were similar to those of CJP. The NO production in macrophage cell lines were increased in a dose-dependent manner, until 5 mg/ml of CJP and 1 mg/ml of PTP compared with control cells, but decreased at higher concentrations. The proliferation of mouse spleen cells were increased in a dose-dependent manner, until 1 mg/ml of CJP and PTP compared with control cells but decreased at higher concentrations. The NO production in macrophage cell lines treated with PTP and CJP were increased in a dose-dependent manner, compared with untreated control cells until the concentrations of $1{\sim}5$ mg/ml (CJP) and 1 mg/ml (PTP) but decreased at higher concentrations than that. The proliferation of mouse spleen cells treated with PTP and CJP were increased in a dose-dependent manner, compared with untreated control cells until the concentration of 1 mg/ml but decreased at higher concentrations than that.