• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.11
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• pp.1316-1326
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• 2017

We evaluated the proximate compositions of raw materials, total polyphenols, total flavonoids, and radical scavenging activities of roasted maize tea according to cultivation period and variety. Proximate compositions of raw materials were significantly different according to cultivation period and variety, and quality characteristics of roasted maize tea extracts were significantly different according to cultivation period. Total polyphenols, total flavonoids, and radical scavenging activities of roasted maize tea were significantly different before and after roasting. The total polyphenol content of Pyeonggangok cultivar sown on April 5th was elevated about 3.60-fold before and after roasting by $3.42{\pm}0.16$ and $12.22{\pm}0.67mg$ gallic acid equivalents/g, respectively. Overall, total polyphenol content was higher in roasted maize tea produced using maize sown on April 5th. 1,1-Diphenyl-2-picrylhydrazyl radical scavenging activity of Gangdaok cultivar sown on April 5th was elevated about 31.6-fold before and after roasting by $7.61{\pm}1.93$ and $240.37{\pm}8.82mg$ Trolox equivalents (TE)/g, respectively. 2,2'-Azino-bis-3-ethylbenzothiazoline-6-sulfonic acid radical scavenging activity of Pyeonggangok cultivar sown on April 5th was elevated about 5.5-fold before and after roasting by $153.84{\pm}1.32$ and $843.54{\pm}3.64mg$ TE/g, respectively. The correlation between proximate compositions of raw materials and quality as well as antioxidant characteristics of roasted maize tea showed overall significance.

• Korean Journal of Food Science and Technology
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• v.41 no.4
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• pp.386-391
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• 2009

To verify the possibility of manufacturing a germinated rough rice tea, germinated rough rice was roasted at 200, 220, and $250^{\circ}C$ for 10, 20, and 30 min. The treated rice powder was then put into tea bags and leached for 1, 3, and 5 min, after which their antioxidant, physicochemical, and sensory characteristics were compared. The total polyphenol content and 2,2'-Azino-bis-(3-ethyl benzothiazoline-6-sulfonic acid) (ABTS) radical scavenging activities of the germinated rough rice tea increased as the roasting temperature increased as well as in response to increased roasting and leaching times. Furthermore, the greater the roasting temperature, roasting time, and leaching time, the greater the increase in total soluble solid contents. Moreover, the turbidity and browning index of the germinated rice tea rose as the roasting temperature, roasting time, and leaching time increased. Additionally, the pH tended to decrease as the roasting temperature, roasting time, and leaching time increased. Evaluation of the sensory characteristics of the germinated rice tea revealed that the formation of a Maillard reaction product in the course of heating the rice added a unique flavor, which led to increase preference for the color, flavor, and taste, and therefore, the overall preference.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.10
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• pp.1371-1377
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• 2012

Biological activities of Korean Panax ginseng 55% ethanol extract (KPGE) were investigated. The measured total polyphenol content of KPGE was 357.45 mg/100 g. KPGE showed the highest ${\alpha},{\alpha}$-diphenyl-${\beta}$-picrylhydrazyl (DPPH) and 2,2'-azino-bis-3-ethylbenzo-thiazoline-6-sulfonic acid (ABTS) radical scavenging activities of 80% and 86% at 1,000 ${\mu}g/mL$, respectively. DPPH and ABTS radical scavenging activities significantly increased in a KPGE concentration-dependent manner. SOD-like activity of KPGE (1, 10, and 100 ${\mu}g/mL$) increased from 22% up to 33% at KPGE concentrations of 500 and 1,000 ${\mu}g/mL$. KPGE treatment significantly suppressed the generation of pro-inflammatory mediators, including nitric oxide (NO), prostaglandin $E_2$ ($PGE_2$), and cytokines (tumor necrosis factor-alpha: TNF-${\alpha}$, interleukin-6: IL-6, interleukin-$1{\beta}$: IL-$1{\beta}$), in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages. KPGE demonstrated strong anti-inflammatory activity that reduced NO and $PGE_2$ production in LPS-stimulated RAW 264.7 cells. Even low concentrations of KPGE (1 and 10 ${\mu}g/mL$) reduced $PGE_2$ and NO production in RAW 264.7 macrophages without LPS-stimulation, respectively. At concentrations of 100, 500, and 1,000 ${\mu}g/mL$, TNF-${\alpha}$, IL-$1{\beta}$ and IL-6 production were significantly suppressed. The results of our study suggest the potential of Korean Panax ginseng as an excellent antioxidant substance for inhibiting inflammatory mediators. Therefore, Korean Panax ginseng (KPGE) may be used as a therapeutic approach to various inflammatory diseases.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.62 no.4
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• pp.352-360
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• 2017

This study evaluated the quality characteristics, polyphenolic compounds, and radical scavenging activity of cooked-rice added to commercially available mixed grains. L-value of cooked-rice with various mixed grains decreased compared to that of cooked-white rice; however, a- and b-values increased. Hardness and elasticity of cooked-rice added to various mixed grains were significantly lower in the pressure cooker compared to the electric cooker. There was no significant difference in adhesiveness and stickiness between rice from the electric cooker and pressure cooker. Total polyphenol and flavonoid contents of cooked-rice added to various mixed grains were significantly increased. The average total polyphenol content of cooked-rice added to various mixed grains cooked in an electric cooker and pressure cooker were $16.50{\pm}3.86$ and $15.88{\pm}3.52mg$ gallic acid equivalent /100 g, and flavonoid contents were $1.58{\pm}0.00$ and $1.55{\pm}0.02mg$ catechin equivalents/100 g, respectively. The average of 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity was $9.27{\pm}2.62$ and $8.72{\pm}2.41mg$ trolox equivalent (TE)/100 g, and 2,2'-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) radical scavenging activity was $22.89{\pm}4.60$ and $23.07{\pm}4.49mg$ TE/100 g for cooked-rice added to various mixed grains cooked in an electric cooker and pressure cooker, respectively. Phenol content and radical scavenging activity of cooked rice was in proportion to the amount of added grains, such as brown rice, colored rice, barley, soybean, and sorghum.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.64 no.4
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• pp.452-458
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• 2019

Coix lacryma-jobi var. ma-yuen (Rom. Caill.) Stapf (CL), which contains riboflavin and coixol, has traditionally been used to treat cancer and arthritis. However, no method for the simultaneous determination of riboflavin and coixol in CL sprouts has been established. In this study, we established and validated a high-performance liquid chromatography-diode array detection (HPLC-DAD) method for the identification and quantification of two reference markers, riboflavin and coixol, in CL sprout extracts. CL sprouts (whole sprouts and leaves) were subjected to extraction with 70% ethanol at room temperature and at 80 ℃ under reflux conditions. The two extractions were validated with respect to specificity, accuracy, precision, and linearity. The content of the two reference markers was highest in leaves extracted under reflux conditions (riboflavin, 8.23 ± 0.32 mg/g; coixol, 5.95 ± 0.04 mg/g). We also investigated the antioxidant activity of the extracts via 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS⁺) scavenging assays. The results indicated that extracts obtained from sprouts under reflux conditions had the strongest antioxidative effects (DPPH half maximal inhibitory concentration [IC₅₀], 68.9 ± 4.1 g/mL; and ABTS, IC₅₀, 34.9 ± 0.1 g/mL). These results can serve as baseline data for the simultaneous determination of the two reference marker compounds, riboflavin and coixol, and development of functional food materials using CL sprouts.

• Korean Journal of Food Science and Technology
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• v.45 no.1
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• pp.97-103
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• 2013

Pine bark extract is made from the bark of Pinus densiflora which naturally contains occurring phytochemicals such as phenolic compounds. PineXol$^{(R)}$ from products of pine bark extract is sold under the brand name. The aim of this study was to evaluate the total phenol, total flavonoids contents and antioxidant activity of the PineXol$^{(R)}$ as well as to assess the lipid accumulation during adipogenesis of 3T3-L1 cells. Our results demonstrate that the total phenolic and flavonoids contents of the PineXol$^{(R)}$ were $717.40{\pm}6.86$ GAE mg/mL and $54.44{\pm}0.01$ RE mg/mL, respectively. The antioxidative activities of the PineXol$^{(R)}$ were significantly increased in a dose dependent manner on DPPH (1,1-Diphenyl-2-picryl hydrazyl) radical scavenging, ABTS (2,2'-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt) radical scavenging, FRAP (ferric reducing antioxidant power) activity, reducing power, nitrite radical scavenging activity and ORAC (Oxygen radical absorbance capacity) value. In addition, the PineXol$^{(R)}$ inhibited the adipocyte differentiation of 3T3-L1 preadipocytes. Exposure to 200 ${\mu}g/mL$, PineXol$^{(R)}$ significantly reduced lipid accumulation (~80%) in 3T3-L1 cells compared to control cells.

• Korean Journal of Food Science and Technology
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• v.48 no.5
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• pp.508-514
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• 2016

Effects of the ethyl acetate fraction from gomchwi (Ligularia fischeri) extract against high $glucose/H_2O_2-induced$ oxidative stress and in vitro neurodegeneration were investigated to confirm the physiological property of the extract. The ethyl acetate fraction of gomchwi extract showed the highest total phenolic contents than the other solvent fractions. An anti-hyperglycemic activity of the ethyl acetate fraction was evaluated using the ${\alpha}-glucosidase$ inhibitory assay, and the half maximal inhibitory concentration ($IC_{50}$) value for ${\alpha}-glucosidase$ was found to be $727.64{\mu}g/mL$. In addition, the ethyl acetate fraction showed excellent 2,2'-azino-bis (3-ethylbenzthiazoline-6-sulfonic acid) diammonium salt radical scavenging activity, and inhibition of malondialdehyde production. The ethyl acetate fraction also decreased intracellular reactive oxygen species, whereas neuronal cell viability against high glucose/$H_2O_2$-induced cytotoxicity was found to be increased. Finally, 3,5-dicaffeoylquinic acid as a main phenolic compound in the ethyl acetate fraction was analyzed by high-performance liquid chromatography. These results suggest that gomchwi might be a good natural source of functional materials to prevent diabetic neurodegeneration.

• Korean Journal of Food Science and Technology
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• v.49 no.4
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• pp.430-437
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• 2017

The protective effect of Pteridium aquilinum on high glucose-induced cytotoxicity was examined in vitro to investigate the relationship between diabetic condition and neuronal dysfunction. The ethyl acetate fraction of P. aquilinum (EFPA), with total phenolic content of 265.08 mg gallic acid equivalent/g, showed higher 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid)/2,2-diphenyl-1-picrylhydrazyl radical scavenging activities and lipid peroxidation inhibitory effect than any other fraction. In addition, EFPA showed a significant reduction in the inhibitory effect on ${\alpha}$-glucosidase activity ($IC_{50}$ value=$205.26{\mu}g/mL$) compared to the acarbose positive control. The anti-oxidative effect in PC12 cells, protective effects on high glucose-induced oxidative stress in neuronal cells, and neurotoxicity were measured using 2',7'-dichlorofluorescin diacetate, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazoliumbromide, and lactate dehydrogenase assays, respectively. EFPA showed conspicuous inhibitory effect on cellular reactive oxygen species production and neuronal cell apoptosis. Finally, kaempferol-3-glucoside was identified as the main phenolic compound of EFPA using high performance liquid chromatography.

• Korean Journal of Food Science and Technology
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• v.50 no.1
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• pp.117-121
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• 2018

Puffing process modifies the chemical and physical properties of the grains. In this study, oats were puffed by subjecting them to pressure of 1.0 and 1.2 MPa, following which the bioactive constituents and antioxidant activities in the oat extracts were investigated. The polyphenol content in puffed oat extracts increased in a pressure-dependent manner (109 and 157 mg gallic acid equivalent/100 g at 1.0 and 1.2 MPa, respectively). In addition, gallic acid was synthesized after puffing ($518{\mu}g/g$ of extract at 1.0 MPa) and was the most abundant phenolic acid in puffed oats. The antioxidant activities, which were determined by 1, 1-diphenyl-2-picrylhydrazyl (DPPH) and 2, 2-azino-bis-3-ethylbenzothiazoline-6-sulphonic acid (ABTS) radical scavenging activities, were improved in oat extracts after puffing (+245 and +184% at 1.2 MPa, respectively). In conclusion, puffing process of oats increased the extractability of polyphenols, including gallic acid, which positively affected its antioxidant activities. These results will provide useful information when using puffed oats for food production.

• Journal of Food Hygiene and Safety
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• v.33 no.2
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• pp.140-145
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• 2018

The skin of the human body occupies the largest surface area of the body and acts as a protection for the person's internal organs. As such, the skin is a major target of oxidative stressors, and these oxidative stressors are known to contribute to skin aging over the course of time. For the most part, an antioxidant is an effective approach to utilize to prevent symptoms related to the reactive oxygen species (ROS)-induced aging of the skin. Therefore, we investigated the antioxidant and anti-aging activity of the leaves of the Quercusaliena Blume extract (QBE). In our study, we confirmed that the cell viability tested with XTT {2,3-bis(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide innersalt} assay was not affected up to a concentration of $100{\mu}g/mL$. In addition, the cell viability of HDF cells induced by hydrogen peroxide was recovered from 81% to 104% after treatment with QBE, which showed the greater protective effect than that of ascorbic acid. Treatments of QBE dose-dependently inhibited reactive oxygen species (ROS) production in HDF cells induced by hydrogen peroxide, which correlated with their protective effects on cell viability. Since QBE treatment exhibited the suppression effect of skin aging by decreasing the ROS production, QBE could be used as a not only natural anti-aging but also antioxidant resource.