• Journal of Bio-Environment Control
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• v.15 no.4
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• pp.377-384
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• 2006

This study was conducted to investigate the effects of chemical application and amout of soil moisture on low temperature stress of cucumber seedling under the greenhouse conditions. When chilling treatments ($2^{\circ}C$) were begun at 07:00AM, survival rates of seedlings of two conditions; -0.3 bar and -5.5 bar were 28.3% and 83.3% respectively. But when chilling treatments were begun at 6:00PM - even the soil moisture condition was -0.3 bar - the survival rate was above the 87%. When reducing the soil moisture from -0.3 bar to -9.0 bar, ABA content in leaf was inc.eased by 6.5fo1d. Spraying of abscisc acid (ABA) before or after the chilling significantly increased the survival rates of seedlings, decreased the amounts of leaking electrolytes and prevented the yield reductions. ABA application on the soil before the chilling appeared to be more effective than the application after the chilling with foliar spray. Spraying of ABA ($10^{-5}M$), urea (0.2%) or $KH_2PO_4$ was effective in counteracting the low temperature, which causes growth deterioration and yield reduction in cucumbers.

• Journal of Life Science
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• v.30 no.5
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• pp.411-419
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• 2020

The development of GM crops has gained significant economic importance, and the number of countries cultivating commercial GM crops has continuously increased since the 1960s. Globally, the area given to cultivating GM soybean, maize, cotton, and canola alone had reached 114 million hectares by 2007. Although the economic importance of cultivating and commercializing GM crops has increased, there is still a need to assess their agricultural traits in comparison to non-GM produce. This study evaluated the agricultural traits of GM rice containing the drought-tolerant gene CaMsrB2 and standard rice to investigate any unintended effects of genetic engineering. The GM and non-GM rice were compared in terms of various agricultural traits in a drought greenhouse and an irrigated paddy field. There was no statistical difference in the field-grown crops, but there was a statistically significant difference in both tiller number and yield in the greenhouse. These results therefore suggest that GM rice lines containing the CaMsrB2 gene are superior in performance to non-GM rice in drought stress conditions and could be grown in drought-prone areas where drought intolerant rice may not be able to grow.

• The Korean Journal of Food And Nutrition
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• v.19 no.2
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• pp.219-226
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• 2006

This study was carried out to optimize the extraction conditions of oleoresin from garlic and to investigate its physicochemical changes during storage at $4^{\circ}C\;and\;25^{\circ}C$. Ethanol was used as solvent for extraction of oleoresin from garlic. On the basis of yield and thiosulfinate contents, the optimum mixing ratio of garlic to ethanol, extraction temperature, time, and number of extraction repeats were found to be 1 to 2(w/v), $30^{\circ}C$, 3 hours, and three extraction repeats, respectively. The yield and thiosulfinate contents of garlic oleoresin under the above condition were 14.52% and $209.93{\mu}mol/g$, respectively. Five volatile sulfide compounds were identified by GC/MS of garlic oleoresin, i.e., diallyl disulfide, methyl allyl trisulfide, 3,4-dihydro-3-vinyl-1,2-dithiin, 2-vinyl-4H-1,3-dithiin and diallyl trisulfide. After 30 days of storage at $4^{\circ}C$, the thiosulfinate content of garlic oleoresin was $32.37{\mu}mol/g$, while there was no detectable amount of thiosulfinate in the oleoresin stored at $25^{\circ}C$. Brown color and turbidity increased significantly during the storage of garlic oleoresin at $25^{\circ}C$ as compared to storage at $4^{\circ}C$, while relatively little change in acidity was observed in the oleoresin regardless of storage temperature.

• Asian-Australasian Journal of Animal Sciences
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• v.23 no.12
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• pp.1657-1667
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• 2010

Direct-fed microbials (DFM) are dietary supplements that inhibit gastrointestinal infection and provide optimally regulated microbial environments in the digestive tract. As the use of antibiotics in ruminant feeds has been banned, DFM have been emphasized as antimicrobial replacements. Microorganisms that are used in DFM for ruminants may be classified as lactic acid producing bacteria (LAB), lactic acid utilizing bacteria (LUB), or other microorganisms including species of Lactobacillus, Bifidobacterium, Enterococcus, Streptococcus, Bacillus and Propionibacterium, strains of Megasphaera elsdenii and Prevotella bryantii and yeast products containing Saccharomyces and Aspergillus. LAB may have beneficial effects in the intestinal tract and rumen. Both LAB and LUB potentially moderate rumen conditions and improve feed efficiency. Yeast DFM may reduce harmful oxygen, prevent excess lactate production, increase feed digestibility, and improve fermentation in the rumen. DFM may also compete with and inhibit the growth of pathogens, stimulate immune function, and modulate microbial balance in the gastrointestinal tract. LAB may regulate the incidence of diarrhea, and improve weight gain and feed efficiency. LUB improved weight gain in calves. DFM has been reported to improve dry matter intake, milk yield, fat corrected milk yield and milk fat content in mature animals. However, contradictory reports about the effects of DFM, dosages, feeding times and frequencies, strains of DFM, and effects on different animal conditions are available. Cultivation and preparation of ready-to-use strict anaerobes as DFM may be cost-prohibitive, and dosing methods, such as drenching, that are required for anaerobic DFM are unlikely to be acceptable as general on-farm practice. Aero-tolerant rumen microorganisms are limited to only few species, although the potential isolation and utilization of aero-tolerant ruminal strains as DFM has been reported. Spore forming bacteria are characterized by convenience of preparation and effectiveness of DFM delivery to target organs and therefore have been proposed as DFM strains. Recent studies have supported the positive effects of DFM on ruminant performance.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.10
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• pp.1625-1632
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• 2005

This study was conducted to monitor the extraction yields and functional properties from cabbage by a response surface methodology. The extract yield was maximized as 44.47$\%$ under the temperature of 79.86$^{\circ}C$, ethanol concentration of 56.84$\%$ and solvent to sample ratio 25.58 mL/g . The maximum value of electron donating ability was 85.46$\%$ at 46.38$^{\circ}C$,57.06$\%$ of ethanol concentration and 27.71 mL/g of solvent to sample ratio. The maximum value of tyrosinase inhibitory effect was 69.37$\%$ at 37.5$^{\circ}C$,47.71$\%$ of ethanol concentration and 16.03 mL/g of solvent to sample ratio. The maximum value of SOD-like activity was 48.36$\%$ in 66.12$^{\circ}C$, 70.35$\%$ of ethanol concentration and 29.13 mL/g of solvent to sample ratio. Estimated conditions for the maximized extraction including yield, electron donating ability and SOD-like activity were 20 $\∼$ 30 mL/g in ratio of solvent to sample, 25$\∼$85$\%$ in ethanol concentration, and 40$\∼$90$^{\circ}C$ in extraction temperature.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.34 no.s02
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• pp.66-80
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• 1989

Salt injury in rice is caused mainly by the salinity in soil and in the irrigated water, and occasionaly by salinity delivered through typhoon from the sea. The salt concentration of rice plants increased with higher salinity in the soil of the rice growing. The climatic conditions, high temperature and solar radiation and dry conditions promote the salt absorption of rice plant in saline soil. The higher salt accumulation in the rice plant generally reduces the root activity and inhibits the absorption of minerals of rice plant, resulting the reduction of photosynthesis. The salt damages of rice plant, however, are different from different growth stage of rice plants as follows: 1. Germination of rice seed was slightly delayed up to 1.0％ of salt concentration and remarkably at 1. 5％, but none of rice seeds were germinated at 2.5％. This may be due to the delayed water uptake of rice seeds and the inhibition of enzyme activity, 2. It was enable to establish rice seedlings at seed bed by 0.2％ of salt concentration with some reduction of leaf elongation. The increasing of 0.3％ salt concentration caused to the seedling death with varietal differences, but most of seedlings were death at 0.4％ with no varietal differences. 3. Seedlings grown at the nursery over 0.1％ salt, gradually reduced in rooting activity after transplanting according to increasing the salt concentration from 0.1％ up to 0.3％ of paddy field. However, the seedlings grown in normal seed bed showed no difference in rooting between varieties up to 0.1％ but significantly different at 0.3％ between varieties, but greatly reduced at 0.5％ and died at last in paddy after transplanting. 4. At panicle initiation stage, rice plant delayed in heading by salt damage, at meiotic stage reduced in grains and its filling rate due to inhibition of glume and pollen developing, and salt damage at heading stage and till 3 weeks after heading caused to reduction of fertilization and ripening rate. In viewpoint of agricultural policy the overcoming strategy for salt injury is to secure sufficient water source. Irrigation and drainage systems as well as underground drainage is necessary to desalinize more effectively. This must be the most effective and positive way except cost. By cultural practice, growing the salt tolerant variety with high population could increase yield. The intermittent irrigation and fresh water flooding especially at transplanting and from panicle initiation to heading stage, the most sensitive to salt injury, is important to reduce the salt content in saline soil. During the off-cropping season, plough and rotavation with flooding followed by drainage, or submersion and drainage with groove could improve the desalinization. Increase of nitrogen fertilizer with more split application, and soil improvement by lime, organic matter and forign soil addition, could increase the rice yield. Shift of trans-planting is one of the way to escape from the salt injury.

• Korean Journal of Food Science and Technology
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• v.35 no.6
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• pp.1104-1109
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• 2003

Response surface methodology (RSM) was used to investigate the effects of the processing parameters on supercritical $CO_2\;(SC-CO_2)$. extraction of total carotenoids and ${\beta}$-cyptoxanthin from Citrus unshiu press cake. The parameters tested were $SC-CO_2$ pressure, dynamic extraction time, and concentration of ethanol added as the modifier to $CO_2$. Experimental data correlated well with the processing parameters (p<0.01), and there was a high statistically significant multiple regression relationship for the extraction of total carotenoids and ${\beta}-cyrptoxanthin$ ($R^2=0.9789$ and 0.9796, respectively). The optimal processing conditions were extraction pressure 33.4 and 37.3 MPa, extraction time 39.6 and 41.0 min, ethanol concentration 18.6 and 17.0% for total carotenoids and ${\beta}-cryptozanthin$, respectively. Maximum extraction yields predicted by RSM were 61.1 and 95.8% ppm, respectively. The extraction yield of total carotenoids increased asymptotically with the increase of the extraction pressure. It increased in proportion to extraction time and concentration of the cosolvent. The extraction yield of ${\beta}-cryptoxanthin$ increased with extraction pressure, extraction time, and concentration of the cosolvent. The extraction time and the concentration of the cosolvent, and the interaction between extraction time and the concentration of the cosolvent significantly affected the extraction yields of carotenoids from C. unshiu press cake.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.54 no.1
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• pp.7-12
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• 2009

Mungbean should be harvested several times according to its physiological characteristics and weather conditions of cultivation region. In Korea, mungbean is usually sown in June and harvested three or four times, and the cultivated area is being rapidly reduced. Therefore, the author developed cultivation techniques of mechanical harvesting suitable for the weather conditions of the southern part of the Korean peninsula. The optimum sowing time of mungbean for mechanical harvesting in southern part of Korea is around July 20. When sown around July 15, mungbean should be harvested twice and then the mechanical harvesting of mungbean was not possible. Meanwhile, when sown after July 25, the mechanical harvesting was possible but the maturing period was longer and the seed yield was decreased. Therefore, it is safe to say that in Korea the mechanical harvesting of mungbean is possible for the middle part of Korea when the plant is sown before July 20 and for the southern coastal region of Korea when sown after July 20 (if July 20 is set up as the baseline for the southern part of Korea). Out of Keumseong and Owool, which are popularized cultivars in Korea most, Owool is determined to be most appropriate for mechanical harvesting. Owool is favorable for mechanical harvesting because, when compared to Keumseong, it is higher both in plant height and in pod height, and also the seed yield is better.

• Korean Journal of Food Science and Technology
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• v.30 no.1
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• pp.139-145
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• 1998

This study was performed to provide fundamental data on the optimum manufacture condition of oleoresin using citron peel. Oleoresin was extracted from freeze-dried or hot air dried citron peels using various solvents (hexane, ether, dichloromethane, acetone. and methanol), mixing ratio, extraction temperature, and time. As a result, optimum extraction conditions of oleoresin were: solvent mixing ratio 1:10 (w/v), extraction time 2 hours, and extraction temperature $60^{\circ}C$ when used methanol, and their dichloromethane 1:10 (w/v), 4 hours and $20^{\circ}C$, respectively. At optimum extraction conditions, the yield of oleoresin was shown that 35.79% at hot air drying samples, 32.04% at freeze-dried ones when extracted by methanol, but shown 5.86% and 6.16% when used dichloromethane respectively. The number of volatile components present in citron oleoresin were confirmed as thirty two in methnol extracion method and twenty nine in dichloromethane extraction method by GC and GC/MS, respectively. But, in the kinds and amounts of volatile flavor components, relatively greater numbers of volatiles were identified in freeze-dried sample extracted by dichloromethane compared with other methods. In freeze-dried sample extracted by dichloromethane, volatile components of citron oleoresin predominantly occupied by limonene and ${\gamma}-terpinene$ with about 85%. Other important compounds were shown hydrocarbons. such as ${\alpha}-pinene$, myrcene, terpinolene, ${\beta}-farnesene\;and,\;{\delta}-elemene$, and linalool as alcohols.

• Korean Journal of Food Science and Technology
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• v.32 no.3
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• pp.646-653
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• 2000

Using agar and waxy com starch as the wall material, we could encapsulate the purified fish oil. Firstly, we have developed a simple and sensitive method for the quantitative analysis of the microencapsulation yield using 5% cupric acetate pyridine solution. Then, the optimum conditions such as the ratio of [core material] to [wall material]$(X_1)$, the temperature of dispersion fluid$(X_2)$, and the emulsifier concentration$(X_3)$ for the microencapsulation process were determined by using response surface methodology(RSM). The regression model equation for the yield of microencapsulation(Y, %) of purified fish oil upon three kinds of independent variables could be predicted as follows; Y = 100.138621-0.735000$(X_1)$+0.840000$(X_1)(X_2)$+0.817500$(X_1)(X_3)$-0.852500$(X_2)(X_3)$. And the optimum conditions for the microencapsulation of the purified fish oil were the ratio of [core material] to [wall material] of 4.9 : 5.1(w/w), the emulsifier concentration of 0.48%, and dispersion fluid temperature of $19.4^{\circ}C$. The microcapsules containing the purified fish oil showed the highest storage stability at pH 7.0 and $20{\sim}25^{\circ}C$.