• Food Science and Preservation
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• v.23 no.3
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• pp.310-318
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• 2016

This study was performed to investigate changes in the quality characteristics and chemical compounds in garlic shoots by blanching for different time (0, 0.5, 1, 2, 3, and 4 min). The color (L, a, and b values), texture profile (hardness, springiness, chewiness, gumminess, and cohesiveness), total vitamin C, total sugar, total polyphenol and flavonoid, chlorophyll a and b contents, total pyruvate and thiosulfinate contents of the blanched garlic shoots were examined. As the blanching time increased, the L and b values decreased, while the a value increased. Hardness, chewiness, springiness and gumminess of the blanched shoots were significantly lowered with the increasing blanching time. Vitamin C content of raw garlic shoot was 1.62 mg/100 g while that of the blanched garlic shoots was 0.16~0.24 mg/100 g, implying vitamin C loss into blanching water and destruction by heat. The total sugar and polyphenol contents were fluctuated during blanching, but over 75% of their initial levels were retained under all blanching conditions. The total flavonoid contents increased as the blanching time increased. The chlorophyll a content did not show significant change with blanching time, but the chlorophyll b content significantly decreased. These results suggest that blanching for 2 min could be the best for retaining beneficial compounds and desirable quality of garlic shoot.

• Korean Journal of Plant Resources
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• v.21 no.2
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• pp.128-133
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• 2008

This study was conducted to compare the antioxidative effects of Dendranthema zawadskii var. latilobum (Maxim.) Kitam and D. zawadskii var. yezoense (Maek.) Y.M. Lee & H.J. Choi due to the harvest date. Harvested samples at May 9th (early), July 17th (middle) and September 3rd (late stage) were extracted with 80% ethanol, and biological activities and antioxidant substance contents were detected. The earlier harvested samples showed the higher moisture contents and extraction yields. DPPH radical scavenging effect of early harvested D. zawadskii var. latilobum (Maxim.) Kitam ($RC_{50}$ = $0.128\;mg\;{\cdot}\;mL^{-1}$) was similar to BHT ($0.121\;mg\;{\cdot}\;mL^{-1}$). ABTS radical scavenging effects of both species harvested at early stage were higher than that of ascorbic acid which was well-known natural antioxidant. However, both species harvested at late stage showed the highest $Fe^{2+}$ chelating effect, but it was lower than that of EDTA. Total polyphenol and flavonoid contents of both species were higher when samples were harvested earlier stage. However, both species harvested at early stage contained more total polyphenols (79.93 and $75.10\;mg\;{\cdot}\;g^{-1}$) than flavonoids (57.84 and $54.91\;mg\;{\cdot}\;g^{-1}$).

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.5
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• pp.647-652
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• 2008

Quality characteristics of Chrysanthemum indicum L. flower tea were investigated with the number of pan-firing. Total nitrogen, tannin and caffeine contents of tea were increased as the number of pan-firing increased, whereas chlorophyll and total amino acid (AA) contents were decreased. TAA content was in the range of $5,226{\sim}6,561mg%$ with the number of pan-firing. The content of caffeine and chlorophyll was not changed with the number of pan-firing. As the number of pan-firing increased, total polyphenol, flavonoid content, and antioxidant activity was also increased. The highest total polyphenol and flavonoid content was 17.44 and 11.09 mg/g at 7 times pan-firing, respectively. Total antioxidant activity was the highest value of 16.45 mg AA eq/g at 7 times of pan-firing. Based on the sensory evaluation, the best overall quality of the tea was obtained with 5 times of pan-firing.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.4
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• pp.624-630
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• 2010

This study was conducted to determine antioxidant compounds and antioxidative activities of by-products including rice bran and half-crashed rice by rice milling. DPPH, ABTS radical scavenging activities and reducing power have been used to investigate the relative antioxidative activities of 70% EtOH extracts from by-products. The contents of total polyphenol, total flavonoid and $\gamma$-oryzanol in EtOH extracts were measured by spectrophotometric methods, and vitamin E was carried out by HPLC. Ethanol extract from rice bran showed markedly antioxidative activity than that from half-crushed rice. Among EtOH extracts from milling by-products, rice bran of 'Hongjiju' tended to have the most effective antioxidative activity compared to the others. These results suggested that by-products of rice milling have the potent antioxidative activity and these activity are partly due to the antioxidative compounds present in by-products including rice bran and half-crushed rice.

• Applied Chemistry for Engineering
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• v.27 no.3
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• pp.280-284
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• 2016

In this study, the extractable content of each parameters from angelica was confirmed using conventional solvent extraction and microwave extraction in order to extract the functional active ingredient. In addition, the functionality of active ingredients was evaluated by measuring the antioxidant activity and the flavonoids and total polyphenols of the active ingredient extracted from angelica, For the conventional solvent extraction at optimal conditions of the extraction time (2 h), ethanol/pure water volume ratio (60%), the extraction temperature ($60^{\circ}C$), 20.6 wt% of the active ingredient were extracted. Also, when using microwave extraction at optimal conditions of the microwave irradiation time (6 min), microwave intensity (600 W) and ethanol/pure water volume ratio (60 vol%) 22.8 wt% of the active ingredient were extracted. The microwave method required shorter time to complete extraction compared to that of using the conventional solvent extraction method. The antioxidant activity of active ingredients extracted from angelica was 31.46% of DPPH radical scavening activity. The flavonoid content was 14.20 mg QE/mg dw, and total polyphenol content was 11.70 mg GAE/g when using the microwave extraction process.

• The Korean Journal of Food And Nutrition
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• v.29 no.1
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• pp.134-143
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• 2016

We evaluated the antioxidant properties of adzuki beans and the quality characteristics of sediment using various cultivation methods. There were significant differences in total polyphenol and flavonoid contents in beans grown using different methods of cultivation (p<0.05). Also, DPPH and ABTS radical-scavenging activities were significantly different depending on cultivation method (p<0.05). The sediment yield before drying of Chungju-pat, Hongeon, and Arari was 296.64~339.01, 271.36~282.24, and 268.21~292.32%, respectively, and the sediment yield after drying was 71.68~85.41, 77.90~85.19, and 74.15~78.65%, respectively. The L-value of Chungju-pat and Arari sediments revealed a significant difference given different cultivation methods (p<0.05), but Hongeon sediment did not show a significant difference. There was a significant difference in the a- and b-value of adzuki bean sediments cultivated using different methods (p<0.05). The particle size of Chungju-pat, Hongeon, and Arari sediments was 66.21~98.80, 61.62~97.07, and $82.96{\sim}106.71{\mu}m$, respectively, and all were significantly different depending on cultivation method (p<0.05). There were also significant differences in the water absorption index, water solubility index, and swelling power when different cultivation methods were used (p<0.05).

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.198-198
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• 2017

Cultivated varieties of sweet potato were from dry texture type to tender texture type on the basis of consumer preferences. There are many differences in the quantity of sweet potato, starch content, pigment, and sugar content depending on the cultivation season and area, even in the same variety. Therefore, in this study, we attempted to establish optimum time of harvesting through growth characteristics and variation in component like starch, sugar, polyphenol and flavonoid. Four sweet potato varieties were used in this experiment. Among them, Jinhongmi (JHM) & Yulmi (YM) were as dry texture type and Pungwonmi (PWM) & Hogammi (HGM) were as tender texture type. Sweet potatoes were transplanted on 23 May, 2016 and were investigated storage root weight and component contents every 20 days from 60 days to 120 days and surveyed yield at 110, 120, 130 days after transplantation. Result revealed that storage root weight of YM, JHM, and HGM were 30.1, 38.9, 20.8 g respectively in 60 days after transplanting. Storage roots of PWM gerw faster with the weight of 88.2 g. In 120 days after transplanting, storage root weight varied from 88.3 to 118.7 g, HGM was the smallest, and PWM was the largest. Sugar contents of sweet potato ranged from 21.0 to $23.8Brix^{\circ}$ in 60 days after transplanting and from 27.5 to $30.78Brix^{\circ}$ in 120 days after transplanting. In particular, the sugar content of HGM was the highest over $30Brix^{\circ}$ after 80 days. The starch content of dry texture type (YM, JHM) increased from 15.5% to 20.4% and tender texture type (PWM, HGM) increased from 11.0% to 17.3%. Starch content tended to be high in dry type sweet potatoes. The content of polyphenol and flavonoid were highest in 60 days after transplanting and was reduced according to cultivation period. The total yield of PWM was high as 3,154 kg/10a and large storage root of over 250 g accounted for 47.4% in 110 days after transplanting. Storage root (YM, JHM, HGM) of 81~150 g accounted for 34.9% ~ 43.2% in 120 days after transplanting. These are the most marketable. Because consumer in Korea prefers small, round and about 100g size sweet potato. The ratio of large storage root (over 250 g) were increased in all varieties at 130 days after transplanting. Therefore, it is considered appropriate to harvest PWM at 110 days and YM, JHM, HGM at 120 days after transplanting, which planted in late May.

• Korean Journal of Food Science and Technology
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• v.49 no.3
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• pp.318-323
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• 2017

While manufacturing blended tea, the temperature for pan-firing Rhus verniciflua seed (RVS) is important. The pan-firing duration was fixed to 15 minutes according to a sensory test. We then prepared four types of blended teas with varied ratios of RVS; all the four types showed similar pH, $^{\circ}Bx$, and hunter's color values with no significant difference. According to the sensory test, A-type tea blended with RVS was the most preferred. The antioxidant activity of A-type blended tea was evaluated during storage. The changes in the total polyphenol, total flavonoid, and antioxidant activity by DPPH and ABTS assays were monitored during storage at 4, 25, and $40^{\circ}C$ for 28 days. After 28 days of storage, values for total polyphenol content, total flavonoid content, and antioxidant activity were similar to the initial values. Moreover, microbial growth was not observed during that period.

• Korean Journal of Organic Agriculture
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• v.23 no.4
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• pp.987-997
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• 2015

Schisandra chinensis (Sc), a species of the family Schisandraceae used fruits as medicinal herbs. In the study, we performed to determine a comparison of antioxidant activity from Sc water extracts depending on stir-frying and stir-frying with liquids by 30% ethanol pretreatments. The contents of polyphenol and flavonoid, DPPH radical scavenging, ABTS radical scavenging and reducing power activity were measured to evaluate the antioxidant activity. Total polyphenol and flavonoid contents of Sc extracts were increased in stir-frying and 30% ethanol stir-frying pretreatments compared to a control. In particular, contents of stir-frying pretreatments Sc were highest increased at $220^{\circ}C$ treatments. The DPPH radical scavenging activity were highest increased in stir-frying pretreatments at $220^{\circ}C$. And result that measurement of the ABTS radical scavenging, it showed higher activity in 30% ethanol stir-frying pretreatments at $180^{\circ}C$ and $220^{\circ}C$. But Sc in the $140^{\circ}C$ showed higher activity in stir-frying pretreatments. In the reducing power activity, stir-frying pretreatments increased higher than 30% ethanol stir-frying pretreatments at $220^{\circ}C$. As in results, antioxidant activity of Sc water extracts in stir-frying and stir-frying with liquids process increased higher than a control, and it was most effectively in stir-frying pretreatments at $220^{\circ}C$.

• Journal of Korean Society of Forest Science
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• v.104 no.3
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• pp.397-402
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• 2015

This study was carried out to analyze the nutritional composition, bioactive compound and antioxidant activity in fresh sprout of 3 new Kalopanax septemlobus cultivars. Cheong-San, Cheong-Song and Cheong Sun 1 had largest carbohydrate (52.90, 53.12, 55.28%), crude protein (34.23, 31.33, 33.58%) in the proximate composition and had largest K (2.29, 2.22, 2.23%) followed by Ca (0.44, 0.34, 0.37%), Mg (0.24, 0.19, 0.19%) in the mineral contents. Three new cultivars contained a total of 26, 25 and 28 different kinds of amino acids, respectively and the number of essential amino acid is 6, 6 and 7 species, respectively. Also, Cheong-San had higher total polyphenol contents and Cheong-Song had higher total flavonoid contents. DPPH free radical scavenging activity of 70% ethanol, water extracts of Cheong-San and Cheong-Song is higher than others at 100 ppm. In the ABTS radical cation decolorization activity, 70% ethanol extract of Cheong Sun 1, water extract of Cheong-San and Cheong-Song are higher activity than others and all samples have more than 85% ABTS racial cation decolorization activity at 500 ppm. Our results suggest that new K. septemlobus cultivars possess good antioxidant capacities with a high nutritional value and might have potential applications in the food and medical industries.