• Food Science and Preservation
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• v.20 no.5
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• pp.684-690
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• 2013

The antioxidant and photoprotective effects of various extracts from the roots of Rumex crispus L. were evaluated. The concentrations ($IC_{50}$) of various extracts required to exert a 50% reducing effect on a DPPH radical were found to be 0.005~0.093 mg/mL. The ethyl acetate extract showed a more remarkable effect than the positive control ascorbic acid. The concentrations ($QC_{50}$) of the butanol and ethyl acetate extracts required to exert a 50% reducing effect on the singlet oxygen $^1O_2$ were found to be 0.464 and 0.365 mg/mL, respectively. Both extracts were also found to protect the in vitro biological system from the detrimental effect of a singlet oxygen $^1O_2$ on type II photosensitization in E. coli and genomic DNA. Among all the tested extracts, the ethyl acetate and butanol extracts contained higher amounts of total phenolic contents. The results suggest that our study may contribute to the development of new bioactive products with potential applications to the reduction of photo-produced oxidative stress involving reactive oxygen species in living organisms.

• Food Science and Preservation
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• v.24 no.7
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• pp.965-974
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• 2017

This study was carried out to investigate the effect of particle size of naked oat flour (NOF) on physicochemical property and antioxidant activity. The NOF was passed through $250{\mu}m$ and $160{\mu}m$ size sieves to obtain three fractions (fraction A: $250{\mu}m$ or more, fraction B: $160-250{\mu}m$, and fraction C: $160{\mu}m$ or less). Moisture, crude protein, crude fat, and crude ash contents of NOF were 8.4, 15.7, 10.0, and 1.8%, respectively, and these contents were increased as the particle size of NOF decreased. The mineral and free amino acid contents of NOF also had a similar tendency. The contents of total starch, amylose, starch damage, total dietary fiber, ${\beta}$-glucan, total phenolics, and flavonoids in NOF were 56.4%, 21.4%, 11.7%, 11.0%, 4.7%, $237.8{\mu}g/g$ and $90.9{\mu}g/g$, respectively. As the particle size of NOF decreased, total starch, amylose, and starch damage contents increased, whereas total dietary fiber, ${\beta}$-glucan, total phenolic and flavonoid contents decreased. Also, three antioxidant activities of NOF were closely correlated with their total phenolics and flavonoids contents, showing high correlation coefficient values ($R^2=0.87$ and 0.81, respectively).

• Journal of Life Science
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• v.25 no.6
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• pp.673-679
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• 2015

The culture conditions needed to maximize the production of laccase from Pholiota highlandensis mycelia were investigated. Among the tested media for laccase production, Coriolus versicolor medium (CVM; 2% dextrose, 0.4% peptone, 0.6% yeast extract, 0.046% KH₂PO₄, 0.1% K₂HPO₄, 0.05% MgSO₄·7H₂O) showed the highest activity for the enzyme. Then, to optimize culture conditions for laccase activity, the influences of various carbon, nitrogen, phosphorus, and inorganic salt sources in CVM were investigated. The optimum culture medium was 2% fructose, 0.4% peptone with 0.6% yeast extract, 0.05% NaH₂PO₄, and 0.05% MgSO₄·7H₂O as carbon, nitrogen, phosphorus, and inorganic salt sources, respectively. Several aromatic compounds in the medium enhanced laccase activity to varying degrees. Guaiacol induced maximum laccase production, yielding 114.1 U/ml laccase activity after cultivation for 11 days at 25℃. The optimum pH and temperature for laccase production were 8.0 and 35℃, respectively. Native polyacrylamide-gel electrophoresis (PAGE) followed by laccase-activity staining with 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) as the substrate was performed to identify the presence of laccase under the optimum conditions studied. Zymogram analysis of the supernatant culture showed an enzymatic band with a molecular mass of about 90 kDa.

• The Korean Journal of Food And Nutrition
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• v.29 no.2
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• pp.178-185
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• 2016

This study was designed to develop and to qualify a coffee alternative beverage using a mixture of coffee beans and roasted black beans (Rhynchosia nulubilis). Therefore, the total isoflavone content (TIC), total phenol content (TPC), antioxidant activity, anti-inflammatory activity, NFATc1 (Nuclear factor of activated T-cells c1) expression in RANKL (receptor activator of nuclear factor kappa-B ligand)-stimulated RAW264.7 cells and sensory evaluation were measured for 5 different Cb (coffee bean)-RoS (roasted seomoktae) mixture extracts (Cb100RoS0, Cb75RoS25, Cb50RoS50, Cb25RoS75, and Cb0RoS100). Cb0RoS100 had the highest TIC ($516.83{\pm}36.61mg/100g$) and TPC ($18.11{\pm}1.77mg$ TAE/100 g) along with the highest antioxidant activity as measured by DPPH radical scavenging activity ($73.55{\pm}8.11%$) and ABTS radical scavenging activity ($63.27{\pm}7.27%$). Also, Cb0RoS100 showed the highest anti-inflammatory activity as measured by NO production ($13.57{\pm}2.21{\mu}M$) and PGE2 production ($3.25{\pm}0.21ng/mL$). The more the RoS ratio was increased in the mixtures of Cb-RoS, the more the NFATc1 protein expression was decreased in RANKL-stimulated RAW264.7 cells. In case of sensory evaluation, Cb50RoS50 had the highest scores for flavor, delicate flavor and overall quality, which were similar to those in Cb alone (Cb100RoS0). We suggest that the use of RoS replacement instead of Cb in/as a coffee alternative beverage may help to reduce the risk of caffeine-related bone loss and/or bone disease by effectively blocking NFATc1 expression in RANKL-stimulated RAW264.7 cells compared with Cb alone.

• Korean journal of food and cookery science
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• v.33 no.2
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• pp.127-136
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• 2017

Purpose: This study examined the effect of different gluten-free flours on the properties of cookies. Methods: Each gluten-free cookie was made from wheat, brown rice, buckwheat, corn, sorghum, teff, or black rice. Results: Baking loss was highest on sorghum (18.85%) and the lowest on teff (12.73%). The spread factor was highest on brown rice (8.20) and lowest on corn (7.60). The density was similar in all samples (1 g/mL). pH was the highest on buckwheat (6.45) and lowest on wheat (5.96). While L-value, a-value and b-value were lowest on black rice, the ${\Delta}E-value$ was the highest on black rice (35.57). The hardness was highest on wheat (30.28 N) and lowest on teff (14.87 N). The polyphenol and flavonoid content was the highest on buckwheat ($25.97{\mu}g\;GAE/mg$) and the flavonoid content was the highest on black rice ($24.33{\mu}g\;QE/mg$). The DPPH IC50 value was highest on wheat ($352.41{\mu}g/mL$) and lowest on black rice ($33.59{\mu}g/mL$). The ABTS $IC_{50}$ value was highest on wheat ($349.30{\mu}g/mL$) and lowest on black rice ($57.72{\mu}g/mL$). The results of the sensory properties revealed color to be highest on corn (7.33). The top grain was similar in all the samples (5.43-6.57). Flavor was highest on black rice and teff (6.43-6.48). The softness was the highest on wheat, sorghum, teff, and black rice (6.48-7.05). Sweetness was highest on sorghum, teff, and black rice (6.19-6.71). The overall preference also was highest on sorghum, teff, and black rice (6.14-6.48). Conclusion: Gluten-free flours can improve the quality characteristics and antioxidant activities of cookies.

• Korean Journal of Food Science and Technology
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• v.37 no.6
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• pp.970-975
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• 2005

Based on their biological activity, phenols from rosemary extract were evaluated for inhibition of Helicobacter pylori. Contents of total phenolic compounds and inhibition zone of water and ethanol extracts from rosemary were 24.3mg/g and 25.7mg/g, and 11mm, 14mm, and, at $200{\mu}g/mL$ phenol content, 20.9% and 78.2% inhibitory activities were observed, respectively. Electron donating abilities and 2.2-Azino-bis-3-ethylbenzothiazoline-6-sulfonic acid cation radicals of water and ethanol extracts were 89.1% and 62.0% and 98.4% and 96.5%, respectively. Thiobarbituric acid reactive substances values of all extracts were lower than that of control. Ethanol extract showed 98.8% angiotensin-converting enzyme inhibitory activity. Xanthin oxidase inhibitory activities of water and ethanol extracts were very high, at 84.8%, 100%, respectively. These results indicated phenolic compounds from rosemary can be utilize as a potential antioxidant, antimicrobial, anti-hypertension and anti-gout sources.

• Journal of Applied Biological Chemistry
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• v.63 no.3
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• pp.259-265
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• 2020

Antioxidative activities of 50% ethanolic extracts from Du-zhong (Eucommia ulmoides Oliver) leaf and bark were investigated. Yields of the leaf and bark extract were 8.1±0.31 and 17.4±0.89%, respectively. Polyphenol contents of the leaf and bark extract were 64.1±3.35 and 42.4±2.38 ㎍ gallic acid equivalents/mg, respectively. Flavonoid contents of the leaf and bark extract were 24.0±3.15 and 36.7±3.18 ㎍ quercetin equivalents/mg, respectively. As concentration of the leaf and bark extract increased, their antioxidative activities proportionally increased. EC₅₀ values of the leaf and bark extract for cation radical scavenging were 560.6±17.65 and 1,357.4±8.45 ㎍/mL, respectively. EC₅₀ values of the leaf and bark extract for free radical scavenging were 574.2±14.70 and 2,103.1±108.59 ㎍/mL, respectively. EC₅₀ values of the leaf and bark extract for ferric reducing antioxidant power were 319.9±13.42 and 705.9±26.08 ㎍/mL, respectively. EC₅₀ values of the leaf and bark extract for nitrite scavenging were 2,329.2±35.11 and 5,467.6±243.92 ㎍/mL, respectively. In the presence of 74.8 ㎍/mL of the leaf extract and 177.2 ㎍/mL of the bark extract, linoleic acid peroxidation was inhibited by 70.0 and 79.1%, respectively. The Du-zhong leaf extract possessed higher antioxidative activities than its bark extract.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.2
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• pp.250-254
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• 2007

In an attempt to find ways of improving the quality of dried Shiitake mushroom, this study compared a conveyer-type far-infrared drying method with a traditional heated air drying method. The conveyer-type far-infrared dryer was performed at air velocity of 0.6 and 0.8 m/s under drying air temperature of 60, 70 and $80^{\circ}C$, respectively. Drying characteristics, antioxidant activities and the antioxidant compounds of Shiitake mushroom dried by far-infrared dryer were investigated. Generally, drying rate with the conveyer-type far-infrared drying method was faster than that with the traditional heated air drying method. In the conveyer type far infrared drying method, drying rates were increased with increasing temperature and air velocity. The loss of antioxidant activities during the conveyer-type far-infrared drying method at 60-0.6, 60-0.8, and $70^{\circ}C-0.6m/s$ was less than the traditional drying method. However, the loss of antioxidant activities at 70-0.8, 80-0.6, and $80^{\circ}C-0.8m/s$ was higher than that of the traditional drying method. Therefore, the conveyer type far infrared drying conditions with below $70^{\circ}C$ and 0.6 m/s air velocity may produce dried Shiitake mushroom with relatively higher antioxidant activities and antioxidant compounds.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.11
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• pp.1637-1644
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• 2015

To develop health-functional food ingredients for improvement of diabetes, we examined biological activities, including total contents of polyphenols and flavonoids, antioxidant activity, and inhibition of ${\alpha}$-glucosidase and pancreatic lipase activities of ethanol extracts from unripe fruit of Momordica charantia L. cultivated in Hamyang, Korea. Ethanol extracts were tested using different ethanol concentrations (0%, 30%, 50%, and 70%) and temperatures ($50^{\circ}C$ and $70^{\circ}C$). Experimental results showed that total polyphenol and flavonoid contents were achieved concentrations of 7.77 mg/g (tannic acid), 7.66 mg/g (gallic acid), and 10.66 mg/g (rutin). The hydroxyl radical scavenging, ABTS cation radical scavenging, and FRAP activities were 82.19%, 42.82%, and 0.19 under the same conditions, respectively. The highest inhibitory activities of ${\alpha}$-glucosidase and pancreatic lipase were achieved in the 70% ethanol extract at $70^{\circ}C$. These results will be useful for development of health functional foods for anti-diabetes using 70% ethanol extract from unripe fruit of bitter melon.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.5
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• pp.642-648
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• 2011

The purpose of this study was to determine the capsaicinoid and antioxidant compounds and to evaluate the biological activity of 40 different pepper (Capsicum annuum L.) breeding lines. Capsaicinoid and ascorbic acid content were measured with HPLC. Total polyphenolic and flavonoid contents and antioxidant activity were measured with spectrophotometric methods. The antiproliferative qualities of the samples against human breast tumor cells (MCF7) were assessed with a MTT assay. The nitric oxide content in the culture media was measured to evaluate the anti-inflammatory qualities of the samples using Raw264.7 macrophages. The capsaicinoid, ascorbic acid, polyphenolic and flavonoid content of the 40 pepper breeding lines were 0.1~204.2 mg/100 g (dry weight basis, DWB), 279.1~1695.5 mg/g (DWB), 2.6~10.2 mg/g (DWB), and 1.4~5.7 mg/g (DWB), respectively. The highest antioxidant, antiproliferative, and anti-inflammatory qualities were found in breeding line numbers 2500, 3201, and 3232, respectively. This study provides basic information useful to plant breeders and biotechnologists who are planning to breed pepper genotypes with high phytochemical content.