• Journal of Life Science
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• v.32 no.5
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• pp.348-354
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• 2022

The leaves, stems, seeds, and roots of Dendropanax morbifera have been used since ancient times as folk medicines for the treatment of headaches, skin diseases, infectious diseases, and other ailments. This study investigated the antioxidant, alcohol metabolism, and hepatoprotective effects of D. morbifera leaf and stem water extracts. The total polyphenol content of the D. morbifera leaf and stem water extracts was 49.56 mg tannic acid equivalent (TAE)/g, and the 1,1-diphenyl-2-picrylhydrazy (DPPH) radical scavenging activity of the D. morbifera leaf and stem water extracts was 84.09% at 1,000 ㎍/ml concentration. The effects of D. morbifera leaf and stem water extracts on alcohol metabolism were determined by measuring the generation of reduced nicotinamide adenine dinucleotide (NADH) by alcohol dehydrogenase (ADH) and acetaldehyde dehydrogenase (ALDH). The ADH and ALDH activities of D. morbifera leaf and stem water extracts were increased in a dose-dependent manner at 37.68% and 41.67%, respectively, at a 1,000 ㎍/ml concentration. The D. morbifera leaf and stem water extracts showed significant protective effects against tacrine-induced cytotoxicity in HepG2 cells at 50 ㎍/ml. Based on our results, we concluded that D. morbifera leaf and stem water extracts may be used as major pharmacological agents, such as antioxidants, alcohol metabolism, and anti-hepatitis remedies.

• Korean Journal of Medicinal Crop Science
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• v.17 no.5
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• pp.328-334
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• 2009

Experimental purpose was to evaluate growth characteristic and abscisic acid (ABA) responses against salt/drought stresses. In the shoot biomass, creeping thyme was tolerated in mild NaCl stress, ranging 0 to 100 mM, while it was severely reduced in higher salinity. Under constant drought stress, the shoot biomass of creeping thyme showed a worse value compared to that of 100 mM NaCl treatment. Chlorophyll degradation was more severe in immature leaf than mature leaf under salt and drought stresses. In salt stress, immature leaf produced much amounts of ABA compared to mature leaf and also immature leaf showed faster increase of ABA than that of mature leaf. In drought stress, immature leaf responded to stress within 24 hours by the increase of ABA, while mature leaf responded to at 72 hours. Our results recommended that the optimal salinity level of creeping thyme was 50~100 mM NaCl.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.43 no.4
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• pp.273-278
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• 1998

Carbohydrate metabolism and partitioning are dependent on relationships between sources and sinks which can be affected by rates of photosynthesis and respiration. Fructan, the major form of stored carbohydrate in tall fescue (festuca arundineacea Schreb.), changes in concentration during growth and in response to the environment. Objectives of this study were i) to examine the content and the composition of carbohydrates in five tissues (mature leaf blade, immature leaf blade, leaf elongation zone, terminal meristem, and root tips) of two tall fescue genotypes, one with high yield per tiller (HYT) and one with low yield per tiller (LYT), and ii) to compare the reserved and utilized carbohydrates among above five different tissues, particularly between the leaf elongation zone and root tips. The established vegetative tillers of the HYT and LYT genotypes were grown in a controlled-environment growth chamber. Water-soluble carbohydrate (WSC) in the leaf elongation zone was about 22% of dry weight in the HYT and about 19% in the LYT genotype. The root tip also had high WSC, about 12% of dry weight in the HYT and 6% in the LYT genotype. Hexoses and sucrose were the major components of total WSC in all tissues except the leaf elongation zone. The growing tissues (sinks), i.e., the leaf elongation zone and root tip, had a high proportion of low degree of polymerization fructan, i.e., 3 to 8 hexose units.

• Magazine of the Korean Society of Agricultural Engineers
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• v.28 no.2
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• pp.31-41
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• 1986

Knowledge of the degree of yield reduction due to water stress at different crop growth stages in rice production is important for rational scheduling of irrigation during periods of insufficient water supply. Previous studies to determine the degree of yield reduction duo to water stress suffered from interruptions by rain during experiment. Also the findings did rot relate the degree of water stress to the soil water potential and water deficit status of rice plants. In this study, two years experiments were conducted using the high yielding rice varieties, an Indica x Japonica (Nampoong) and a Japonica variety(Choochung). These were grown in 1/200$^{\circ}$ plastic pots placed under a rainfall autosensing, sliding clear plastic roof facility to control rainfall interruptions. The results obtained were as follows. 1.The two varieties differed in the growth stage most sensitive to water stress as well as the degree of yield reductions. When rice plants were stressed to the leaf rolling score 4 and soil water potential of about - 20 bar at major crop growth stages which included heading, booting, non-effective tillering, panicle initiation and early tillering stages, the yield reductions in the Indica x Japonica variety were 58%, 34%, 27%, 22%, and 21%, respectively, whereas in the Japonica vairety they were 23%, 36%, 1%, 13% and 22%, respectively. This result show that the recommended drainage during non-effective tillering is valid only for the Japonica variety. Sufficient irrigation at booting, heading and early tillering stages are necessary for both varieties. 2.The two varieties showed visible wilting symptoms when the soil water potential dropped to about - 3.0 bar. The Japonica variety showed more leaf rolling than the Indica X Japonica. However, it had a higher retention of leaf water content and greater stomatal diffusive resistance. When the soil water potential dropped, the Japonica variety showed leaf rolling score (LRS) 1 at 0 soil-5. 0 bar and LRS 2 at 0 soil -6.0 bar while the Indica X Japonica showed LRS 1 at 0 soil - 5.5 bar and LRS 2at 0 Soil - 9.0 bar. The stomatal diffusive resistance was maximum at the second top leaf blade in both varieties at intermediate water stress of 0 soil - 4.5 bar. 3.The number of days that was required for the soil water potential to drop to-3. 0 bar and to - 20.0 bar after drainage of irrigation water from the 20cm deep silty clay loam soil in the pots were 6 and 13 days, respectively for booting stage, and 7 and 11 days, respectively for heading stage, 9 and 12 days, respectively for panicle initiation stage, and 12 and 19 days, respectively for early tillering stage. 4.Water stress during the early tillering stage recorded the longest delay in beading time, the largest reduction in panicle numbers and a substantial yield decrease of 20%. This calls for better water management to ensure the availability of water at this stage, particularly during drought periods. In addition, a reexamination of the conventional inter-drainage practice during the non-effective tillering stage is necessary for the high yielding Indica X Japonica varieties.

• Journal of the Korean Institute of Landscape Architecture
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• v.28 no.4
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• pp.21-28
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• 2000

This study is conducted to analyze effects of soil moisture on the growth of maple(Acer palmatum) under indoor low light intensity. Maples grew under three different light intensities such as sunny place(average 353.2W/$m^2$), half shade(average 7.7 W/$m^2$) and shade/(average 1.9W/$m^2$).Under half shady and shady condition, each 24 planters(2 maples planted in each planter) were used and divided into 3 groups treated with different watering points. Three levels of soil water potential were set for watering points, such as -200mbar, -300mbar or -500mbar. Under sunny condition, there were only group of 8 planters, as comparison. Watering was applied when soil water potentials reached -500maber. The results of plant growth experiment are as followed. 1. Under the shady condition, 32 maples died among 48 maples for 7 months. 9 maples survived, watered at soil water potential -200mbar, 5maples at -300mbar and 2maples at -500mbar. 2. Leaf water content ratios were higher under lower light intensity. For the cell wall became thinner under lower light intensity. 3. Maples in shady were easy to die due to having thin cell wall, therefore they were easy to loss the turgor pressure. 4. In case of half shady condition, the group, watered at soil water potential -200mbar, had much smaller amount of rootlet than -300mbar, because there were excessive soil water. The group, watered at soil water potential -500mbar, had smaller amount of rootlet than -300mbar and there was a remarkable difference in leaf water potential in spite of nearly same soil water potential, because leaves received the water stress under lower soil water potential. 5. When maples grew soundly, the leaf water potential was largely influenced by the soil water potential.

• Journal of Bio-Environment Control
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• v.19 no.4
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• pp.223-228
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• 2010

This experiment was conducted to select optimal cultivars of long leaf vase life for flower arrangements among 21 Hosta cultivars that were selected based on their ornamental value. As a result of the investigation, the cultivar with the longest leaf vase life was 'June' with 29 days record. The cultivars with a more than 10 days record were 'Remember Me', H. lancifolia var. grandiflora, 'Grand Marquee', 'Dress Blue', 'Blue Dimples', 'Frosted Dimples', 'Birchwood Park's Gold', 'Krossa Regal', and 'Paradise Power'. These 10 cultivars had a high chlorophyll content, and had low chlorophyll content changes over time and were high in water absorption. The 10 selected cultivars had equal characteristics of increase in chlorophyll content within a certain period of time. These cultivars have a longer vase life when compared to others. This indicates the potential to develop better materials be use with flower arrangements.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.1
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• pp.118-125
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• 1999

Effects of adding of Angelica keiskei Koidz flour on the quality characteristics of bread were inves tigated. The content of total dietary fiber was 31.89% in flour of Angelica keiskei Koidz leaf and 43.37 % in that of stem. The content of insoluble dietary fiber increased by blanching, but those of soluble dietary fiber and insoluble dietary fiber increased by steeping in NaCl solution. In the results of sensory evaluation of Angelica keiskei Koidz flour, leaf steeped in NaCl solution and blanched stem showed good overall preference. With the addition of Angelica keiskei Koidz flour, water binding capacity and loaf weight increased, while the loaf volume decreased. The loaf volume of bread added with leaf steeped in NaCl solution and blanched stem were higher than those added with natural Angelica keiskei Koidz flour. The lightness and redness values decreased with the increase of Angelica keiskei Koidz flour content in bread but yellowness values increased. In the texture analyzer measurement for bread added with Angelica keiskei Koidz flour, hardness and springiness somewhat increased, while cohesiveness, gumminess and chewiness decreased. As the results of sensory evaluation of bread added with Angelica keiskei Koidz flour, the score of the breads added with 5% leaf steeped in NaCl solution and 5%, 10% blanched stem were somewhat lower than those of control bread. In terms of rate of addition of Angelica keiskei Koidz flour, the bread added with leaf at 5% level, natural stem at 5% level and stem by blanching at 5%, 10% level had good overall preference.

• Korean Journal of Soil Science and Fertilizer
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• v.46 no.6
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• pp.409-416
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• 2013

Millet and sorghum are major dryland cereal crops, however their growth and productivity is limited by soil water stress with varying intensity. The major objective of this study was to evaluate water stress of millet and sorghum yield under drainage classes of poorly drained soil and to test the effect of the installed pipe drainage in poorly drained paddy soil to minimize crop stress. The research was carried out in poorly drained paddy fields located at alluvial slopping area resulting in non-uniform water content distribution by the inflow of ground water from the upper part of the field. Stress Day Index (SDI) was determined from a stress day factor (SD) and a crop susceptibility factor (CS). SD is a degree of measurement by calculating the daily sum of excess water in the profile above 30cm soil depth ($SEW_{30}$). CS depends on a given excess water on crop stage. The results showed that sum of excess water day ($SWD_{30}$) used to represent the moisture stress index was lower on somewhat poorly drained soil compared with poorly drained soil on 117 days. CS values for sorghum were 57% on $3^{rd}$ leaf stage, 44% on $5^{th}$ leaf stage, 37% on panicle initiation, 23% on boot stage, and 16% on soft dough stage. For proso millet CS values were 84% on $3^{rd}$ leaf stage, 70% on $5^{th}$ leaf Stage, 65% on panicle initiation, 53% on boot stage, and 28% on soft dough stage. And for foxtail millet the values were 73% on $3^{rd}$ leaf stage, 61% on $5^{th}$ leaf stage, 50% on panicle initiation, 29% on boot stage, and 15% on soft dough stage. SDI of sorghum and millet was more susceptible to excess soil water during panicle initation stage more poorly drained soil than somewhat poorly drained soil. Grain yield was reduced especially in proso millet and Foxtail millet compared to Sorghum.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.2
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• pp.231-238
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• 2008

Quality attributes of fresh-cut sesame leaf (Perilla frutescens var. japonica) as affected by hydrocooling and packing were investigated in terms of weight loss, respiration, vitamin C content, total chlorophyll content, microbial load and sensory properties during storage at 4 and $10^{\circ}C$. Fresh sesame leaf was trimmed and washed with cold water (1, $5^{\circ}C$) as well as tap water ($13^{\circ}C$) for 30 sec 3 times and then packaged in PP (polypropylene) film bag and PETE (polyethylene terephthalate) tray, and stored for 9 days at 4 and $10^{\circ}C$. Weight loss was decreased by washing and packing. Respiration rate was increased slowly over the storage at $4^{\circ}C$. Vitamin C content and total chlorophyll contents of sesame leaf packaged within PETE tray decreased gradually during storage. Hydrocooling and packing within PETE tray treatments resulted in approximately $1{\sim}2\;log\;CFU/g$ reduction of microbial load.

• Journal of the Korean Society of Tobacco Science
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• v.27 no.2
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• pp.226-234
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• 2005

The uncertainty of measurement in nitrate from burley leaf tobacco by continuous-flow analysis method was evaluated following internationally accepted guidelines. The sources of uncertainty associated with the analysis of nitrate were weight of standard and sample, purity of standard, dilution of standard solution, calibration curve, water content, etc. The calculation of uncertainty based on the GUM(Guide to the Expression of Uncertainty in Measurement) and EURACHEM/CITAC Guide. An expanded uncertainty was obtained by multiplying the combined standard uncertainty with a coverage factor (k) calculated from the effective degree of freedom. The concentration of nitrate from burley leaf tobacco was $2.09\%$ and the expanded uncertainty by multiplying by the coverage factor(k, 2.20) was $0.13\%\;at\;a\;95\%$ confidence level.