• Preventive Nutrition and Food Science
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• v.22 no.3
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• pp.223-230
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• 2017

The purposes of this study were to produce polysaccharides from red pepper stems using different extraction methods and evaluate their chemical composition, in vitro biological capacities, and rheological properties. Two polysaccharides were extracted from red pepper stems using an autoclave and alkali treatments, and the extracts were named PAU and PAL, respectively. The contents of total phenolics and flavonoids were significantly higher in PAU than those in PAL. PAU exhibited greater scavenging activities on 2,2-diphenyl-1-picrylhydrazyl radicals, 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt radicals, superoxide radicals, and nitrite compared to PAL, suggesting that PAU served as better antioxidants. Similarly, in vitro inhibitory abilities against carbohydrate hydrolyzing enzymes of PAU were higher than those of PAL. Steady shear rheological analysis demonstrated that PAU showed higher psuedoplastic shear-thinning behavior compared to PAL. Based on the results from dynamic shear rheological properties, it was found that both samples had predominantly viscous behavior rather than elastic behavior.

• The Korean Journal of Food And Nutrition
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• v.24 no.3
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• pp.451-457
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• 2011

The purpose of this study was to evaluate the effects of soybean varieties on the physicochemical and sensory characteristics tofu. Five varieties of soybeans(Daewon, Jinpoung, Hwanggum, Jinmi, and Manni) were selected for these experiments. Proximate composition and total phenolic acids in the soybeans, and the moisture, turbidity, lightness, yield rate, texture characteristics, and sensory characteristics of the tofu were measured. The Hwanggum soybeans had the highest levels of crude lipid and crude ash. There was a significant difference in the moisture and yield rate of the tofu(p<0.05). The crude protein and crude lipid contents of the soybeans affected the hardness and springiness of the tofu. In sensory evaluations, significant differences(p<0.05) were shown in taste, texture, and overall acceptability depending on the tofu by soybean variety. Therefore, one should consider soybean varieties when manufacturing tofu.

• The Korean Journal of Food And Nutrition
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• v.9 no.2
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• pp.137-142
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• 1996

To develop antioxidant substances in plant, phenolic compounds in Bangah (Igodon japonicus, Hara) and antioxidative effects of cell extracts were investigated. Defatted samples of Bangah were extracted with acetone/methanol and the extracts were fractionated Into the free and bound types of phenolics. The equal amounts of fractions were dissolved In soybean oil and autoxidized at 45$^{\circ}C$ for 25 days. Peroxide value and TBA values were determined every 5 days during oxidation. Changes of peroxide and TBA values showed antioxidant effects, which were lower than control during the oxidation periods. The effects of cell extracts were evaluated as high as BHT, 0.02 ppm. The antioxidative effect of insoluble-bound phenolic extract was higher than that of free. The contents of phenolic compounds in insoluble-bound fraction were also higher than free fraction.

• The Korean Journal of Food And Nutrition
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• v.25 no.3
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• pp.447-453
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• 2012

Various types of tea are consumed as a popular beverage worldwide particularly in Asian countries such as Korea, China, and Japan. The purpose of this study was to investigate the mineral contents, antioxidant properties and anticancer activity of Yak-Sun tea that is prepared by six oriental medicinal herbs. The results of the mineral contents were as follows; Ca, Mg, and Na contents were higher than those of green tea, whereas Fe, P, and K contents were lower than those of green tea. The total phenolics and flavonoid content of the Yak-Sun tea were higher than those of green and black teas. The $IC_{50}$ values of DPPH radical, hydroxyl radical, hydrogen peroxide radical scavenging of Yak-Sun tea were 0.78, 1.58, and 2.04 $mg/m{\ell}$, respectively, whereas the radical scavenging values of ${\alpha}$-tocopherol was 0.06, 0.05, and 0.09 $mg/m{\ell}$, respectively. When cancer cells were treated with Yak-Sun tea, the anticancer activity increased in a dose dependent manner. HCT116 colon cancer cell lines were dramatically increased, as compared to other cancer cell lines, such as MCF-7, H460, and MKN45 cell lines. The results of this study demonstrated that Yak-Sun tea could function as a tea to enhance health conditions for antioxidant and anticancer activity.

• Food Science and Preservation
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• v.19 no.5
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• pp.735-743
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• 2012

Purple sweet potato (PSP, Ipomoea batatas) has various biological effects including antidiabetic, anti-inflammatory, and antioxidant activities. In this study, the antioxidant activity of PSP after roasting were compared using DPPH, ABTS, and FRAP assays. In addition, the total phenolics and flavonoid contents, Maillard reaction products, and phenolic acid contents were measured to identify the factors that changed PSP,s antioxidant activity due to roasting. The roasted PSP exhibited significantly higher antioxidant activity than unroasted PSP. In particular, the PSP roasted at $200^{\circ}C$ for 10 min showed the highest antioxidant activity among all the PSPs that were roasted under different conditions. The total phenolic and flavonoid contents, Maillard reaction products and phenolic acid contents markedly increased, corresponding to the general increase in antioxidant activities after roasting. These results suggest that roasted PSP extracts are potential source of natural antioxidants that may be used in certain food applications.

• Culinary science and hospitality research
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• v.21 no.6
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• pp.120-132
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• 2015

The purpose of this study was to provide preliminary information for the utilization extension of Chinese artichoke(Stachys sieboldii Miq) as a functional food material. The effects of the addition of Chinese artichoke powder(0, 3, 6, 9, and 12%) in white bread formulation on phenolics content and antioxidant properties, and sensory analysis(seven-point hedonic test) were examined. The contents of total polyphenols(TPC), flavonoids (TFC), and tannins(TTC) in Chinese artichoke powder were $139.09{\pm}1.97mg\;GAE/g\;dw$, $74.33{\pm}2.69mg\;QE/g\;dw$, and $40.41{\pm}2.54 mg\;TAE/g\;dw$, respectively. As the amount of Chinese artichoke powder increased, the phenolics contents also significantly increased(p<0.001, p<0.001, and p<0.001 on TPC, TFC, and TTC, respectively), the highest TPC($104.27{\pm}0.13mg\;GAE/g\;dw$), TFC($71.03{\pm}1.75mg\;QE/g\;dw$), and TTC($8.76{\pm}0.12mg\;TAE/g\;dw$) were achieved in the white bread having the highest percentage of Chinese artichoke powder(12%). The $IC_{50}$ values of Chinese artichoke extract for 1,1-diphenyl-2-picrylhydrazyl(DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid(ABTS) radical scavenging activities were 1.42 mg/mL and 1.57 mg/mL, respectively. Scavenging activities of DPPH and ABTS radicals of white bread were significantly increased according to the levels of added Chinese artichoke powder(p<0.001 and p<0.001, respectively). In the acceptance test, the white bread containing 9% Chinese artichoke powder was ranked significantly higher than the other groups according to all sensory parameters such as appearance, flavor, taste, texture, and the overall acceptability. Overall, Chinese artichoke enhanced white bread could be developed as an antioxidant-enriched bread with good sensorial properties.

• Food Science and Preservation
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• v.23 no.2
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• pp.259-266
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• 2016

Bitter melon powder (BMP) was used in the preparation of rice nuruk (RN) and makgeolli as one of raw materials. RN containing BMP (BMP-RN) was prepared by adding 0~2.0% (w/w) BMP into rice. Fermentative microbial, and antioxidant characteristics of makgeolli were determined during the fermentation process. pH during fermentation decreased from 4.52 (0% BMP-RN), 4.93 (0.5%), 4.80 (1.0%), and 4.88 (2.0%) on the initial fermentation day (day 0) to 4.15, 4.30, 4.57, and 4.59, respectively, corresponding to increases in acidity from 0.64~0.70% to 1.17~1.28%, respectively. Soluble solid contents increased from an initial 2.2~4.4 g/L (day 0) to 9.0~9.3 g/L, and alcohol level increased up to 13.0% by the end of fermentation (day 7). Soluble phenolic contents increased from 0.92, 1.01, 1.32, and 1.41 mg/mL on day 0, to 1.85, 2.03, 2.24, and 2.48 mg/mL on day 7, respectively, while the levels of 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) diammonium salt (ABTS) radical scavenging activities and ferric reducing/antioxidant power (FRAP) assay increased from 46.95~70.04%, 55.33~74.13%, and 0.629~1.243 on day 0, respectively, to 54.98~83.4%, 70.34~92.39%, and 0.964~1.455 on day 7, respectively. Makgeolli made with BMP-RN had higher soluble phenolic contents and antioxidant activity than those of makgeolli made without BMP-RN. These results suggested that BNP-RN made a functional makgeolli.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.6
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• pp.684-690
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• 2008

To investigate the applicability of hot water extract (PLW) and ethanol extract (PLE) from Phellinus linteus as functional food and cosmeceutical materials, its total flavonoids content, total phenolics content, electron donating ability (EDA), nitrite-scavenging ability (NSA), SOD-like activity, inhibitory effect of tyrosinase and elastase were examined. Total flavonoids contents of PLW and PLE were 17.31 mg/g and 42.61 mg/g, respectively, and total phenolics contents were estimated as 149.92 mg/g for PLW and 432.42 mg/g for PLE. The EDA of PLW and PLE were $6.49{\sim}92.98%$ and $22.61{\sim}94.28%$. The EDA and total phenolics contents had a high correlation of 0.83. The NSA was pH dependent, and was highest at pH 1.2 and lowest at pH 6.0. The NSA of PLE was higher than that of PLW. The SOD-like activities of PLW and PLE were $14.36{\sim}35.21%$ and $17.27{\sim}81.84%$, respectively, and the activity was dependent on the sample concentration. The tyrosinase inhibitory activity was the highest in PLE ($10.51{\sim}80.93%$) while that of PLW was $4.77{\sim}43.69%$. Finally, the elastase inhibitory activity was $10.01{\sim}76.02%$ at PLE. Based on the above results, we deemed that the ethanol extract of Phellinus linteus was the most pertinent for use as functional food and cosmeceutical materials.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.2
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• pp.220-228
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• 2007

The nutritive value and the effect of tannins on the utilization of foliage from three commonly used legumes, Acacia nilotica, Albizia procera, and Sesbania acculeata, were determined. Three mature rumen-fistulated bullocks were used to study in sacco degradability and twelve adult sheep were randomly allocated on the basis of live weight to 4 groups of 3 in each to study the in vivo digestibility of the foliages. In all foliages, the contents of crude protein (17 to 24% of DM) were high. Fibre was especially high in Albizia (NDF 58.8% of DM vs. 21% in Sesbania and 15.4% in Acacia). Contents of both hydrolysable (4.4 to 0.05%) and condensed tannins (1.2 to 0.04%) varied from medium to low in the foliages. Acacia contained the highest level of total phenolics (20.1%), protein precipitable phenolics (13.2%) and had the highest capacity to precipitate protein (14.7%). Drying in shade reduced the tannin content in Acacia and Albizia by 48.6 and 69.3% respectively. The foliages ranked similarly for each of the different methods used to estimate tannin content and activity. Acacia and Sesbania foliage was highly degradable (85-87% potential degradability of DM in sacco), compared to Albizia (52%), indicating a minimal effect of tannins in Acacia and Sesbania. Yet, in vitro, the tannins in the Acacia inhibited microbial activity more than those in Albizia and Sesbania. Following the addition of polyethylene glycol to neutralise the tannins, gas production and microbial growth increased by 59% and 0.09 mg RNA equiv./dg microbial yield respectively in the Acacia, compared to 16-17% and 0.06 mg RNA equiv./dg microbial yield in the other foliages. There was a trend for low in vivo apparent digestibility of N in the Acacia (43.2%) and Albizia (44.2%) compared to the Sesbania (54.5%) supplemented groups. This was likely to be due to presence of tannins. Consistent with this was the low N retention (0.22 and 0.19 g N/g NI) in sheep supplemented with Acacia and Albizia compared to that for the Sesbania (0.32). Similarly, a trend for poor microbial N yield was observed in sheep fed these foliages. Across the foliages tested, an increase in tannin content was associated with a reduction in ruminal fermentation, N digestibility and N retention. For overall nutritive value, Sesbania proved to be the superior forage of the three tested.

• Korean Journal of Food Science and Technology
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• v.44 no.5
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• pp.540-544
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• 2012

The aim of this study was to evaluate the antioxidant activity, total phenolics, flavonoids, and vitamin C contents in peels of 11 commercial fruits commonly consumed in the Republic of Korea. The antioxidant activities were evaluated by ABTS, DPPH radical scavenging methods and reducing power. The peels of plum (Prunus spp.) and golden kiwifruit (Actinidia chinensis) exhibited the highest values of antioxidant activity and total phenolics, while the highest level of ascorbic acid was recorded in the peel of citrus fruit (p<0.05). There were positive correlations between the antioxidant activity assessed by both reducing power and ABTS methods and total polyphenol content ($R^2$=0.6356), suggesting that phenolic compounds are the major contributors to these activities. The results indicate that plum and golden kiwifruit peels can be used as natural antioxidant ingredients and in production of functional foods in the Korean diet.