간행물

Current Research on Agriculture and Life Sciences 경북대농학지

권호리스트/논문검색
이 간행물 논문 검색

권호

Vol. 33 No. 2 (2015년 12월) 6

Original Article

1.
2015.12 구독 인증기관 무료, 개인회원 유료
Poria cocos is an edible and pharmaceutical mushroom with a long history of medicinal use in Korea. For the last 30 years, the domestic cultivated supply of Poria cocos has been unable to meet consumer demand, so Poria cocos is collected in mountainous areas and also imported from China. Thus, to increase the supply of Poria cocos, many artificial cultivation methods have been studied. In this study, Poria cocos is cultivated under different environmental conditions using plastic bags and the results compared. When cultivating Poria cocos at different temperatures (20, 25, 30 and 35oC) and using different numbers of plastic bag layers (1, 2), the most efficient cultivation conditions were a temperature of 25-30oC and 2 plastic bag layers. The fastest growth was at 25-30oC, and the Poria cocos exhibited no weight change when cultivated using layers of plastic bags (1, 2).
3,000원
2.
2015.12 구독 인증기관 무료, 개인회원 유료
This study calculated the overall heat transfer coefficient (U-value) of greenhouse covering materials with thermal screens using a simulation model and then estimated the validity of the calculated results by comparison with measured values. The U-value decreased gradually as the thickness of the air space between the double glazing increased, and then remained essentially constant at thicknesses exceeding 25 mm. The U-value also increased with the difference in temperature between the inside and outside of the hot box. The vigorous convective heat transfer between two plastic films caused unsteady heat flow and then created a nonlinear temperature distribution in the air space. The distance did not affect the U-value at distances of 50~200 mm between the plastic covering and thermal curtain. The numerical calculation results, with and without sky radiation, were in accord with the experimental results for a 30°C temperature difference between the inside and outside of the hot box. In conclusion, a reliable Uvalue can be calculated for a temperature difference of 30°C or more between the inside and outside of the hot box.
4,000원
3.
2015.12 구독 인증기관 무료, 개인회원 유료
The aim of this research was to investigate the anti-oxidantive activities of extracts from Chionanthus retusus leaves, fruits and flower. The content of phenolics were 20.8 mg/g in water extracts and 32.2 mg/g in 90% ethanol extracts from flower. The DPPH free radical scavenging activity of extracts from Chionanthus retusus was above 70% at phenolic concentration 100 μg/mL. The ABTS radical decolorization activities of water and ethanol extracts were both above 80% at 100 μg/mL phenolic concentration, respectively. The antioxidant protection factor(PF) of water and 80% ethanol extracts from leaves was the highest as 2.27 PF and 1.70 PF at 50 μg/mL phenolic concentration. The TBARs inhibition rate of the Chionanthus retusus extracts, was above 70% at 200 μg/mL phenolic concentration. The anti-oxidantive activities of extracts from leaves were shown more active than BHT as a positive control except TBARs. These results confirmed that the extracts from Chionanthus retusus leaves, fruits and flower was shown the high anti-oxidant activity. The results can be expected isolated phenolic compounds from Chionanthus retusus to use as functional beauty food resource.
4,000원
4.
2015.12 구독 인증기관 무료, 개인회원 유료
Abstract In this study, the antioxidant activity of water and ethanol extracts from Hibiscus esculentus, Cirsium japonicum, Zizania latifolia and Kalopanax pictus for functional food source were examined. The optimal conditions for phenolic compounds extraction from medicinal plants were at 50% ethanol with Hibiscus esculentus and Cirsium japonicum var. ussuriense, at 40% ethanol with Kalopanax pictus and at 60% ethanol with Zizania latifolia. The total phenolic contents from the extracts of medical plants were determined to be 2.72~34.15 mg/g in the water extracts and 2.83~34.23 mg/g in the ethanol extracts. The electron-donating abilities (EDA) of the water and ethanol extracts were both above 74% at the low concentration of 50 μg/mL. The ABTS radical-cation decolorization was above 88% at 100 μg/mL concentration in all the extracts of various medicinal plants. The antioxidant protection factor (PF) in the water and ethanol extracts of the Cirsium japonicum var. ussuriense extracts was 1.73 ± 0.02 PF and 1.76 ± 0.01 PF at 50 μg/mL concentration respectively, and was higher than those of the other medicinal-plant extracts. The TBARs inhibition rates of all the medicinal-plant extracts, were above 80% at the 50 μg/mL concentration except Hibiscus esculentus. These results confirmed that the various oriental medicinal plants (Hibiscus esculentus, Cirsium japonicum var. ussuriense, Kalopanax pictus and Zizania latifolia) that were included in this study are useful anti-oxidant and functional-food resources.
4,000원
5.
2015.12 구독 인증기관 무료, 개인회원 유료
Hunter's color value “a” in dried-persimmon of table and full ripe fruit was higher than that in unripe fruit. In case of soluble solid content, full ripe fruit was 50o Brix, the highest degree, while unripe fruit was 40o Brix, the lowest degree. PPO activation of unripe fruit was 4.7, which was higher than table-ripe fruit (0.7) and full ripe (1.0). Polyphenol oxidase activation remained even while drying, but there was no difference in PPO activation degree as drying period increased. Total phenol content of unripe fruit was 101.4, which was higher than table-ripe fruit (57.5) and full ripe fruit (67.4). Total phenol content level increased as drying period increased, which was based on fresh weight. Hardness of unripe and table ripe fruit continued to decrease until three weeks during softening. After that, hardness was high and it started drying. However, in full ripe fruit, hardness increased after two weeks and softening was fast during the drying period, and its weight reduction rate was lower than that of unripe and table ripe fruit.
3,000원
6.
2015.12 구독 인증기관 무료, 개인회원 유료
The antioxidant capacities, total phenolic contents (TPC), and total quercetin contents (TQC) of a red (Chenjujuck), a yellow (Sunpower), and a white (Grasier) onion cultivar were determined in this study. Onion was separated into edible portion and dry skin. In the case of edible portion, the yellow onion had the highest antioxidant activity, followed by the red onion. The white onion showed neither antioxidant activity nor quercetin compounds. On the other hand, the dry skin of the red onion showed higher antioxidant activity than yellow onion skin. The white onion skin had slight antioxidant activity, low TPC, and no quercetin compounds. In addition, the flavonoid compounds of the edible portion and dry skins of these colored onions were analyzed by UFLC(ultra-fast liquid chromatography). The major compounds were quercetin 3,4-diglucoside and quercetin 4- glucoside in yellow and red onion edible portion, whereas the major compounds in yellow and red onion skins were quercetin 4- glucoside, quercetin, and quercetin 3,4-diglucoside.
4,000원