• Korean Journal of Weed Science
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• v.31 no.1
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• pp.96-102
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• 2011

The objective of this study was to find herbicidal compounds in the essential oil of palmarosa (Cymbopogon martini). Of essential oils from basil (Ocimum basilicum), blackpepper (Piper nigrum), clary sage (Salvia sclarea), ginger (Zingiber pfficinale), hyssop (Hyssopus officinalis), nutmag (Myristica fragrance), palmarosa (Cymbopogon martini), fennel (Foeniculum vulgare), sage (Salvia leucantha), and spearmint (Mentha spicta), the herbicidal activity of palmarosa essential oil, which was determined by a seed bioassay using rapeseed (Brassica napus L.), was highest ($GR_{50}$ value, $201{\mu}g\;mL^{-1}$). In palmarosa essential oil, 11 volatile organic chemicals were identified by gas chromatography-mass spectometry with solid-phase micro-extraction apparatus and the major constituents were geraniol (40.23%), geraniol acetate (15.57%), cis-ocimene (10.79%), and beta-caryophyllene (8.72%). The $GR_{50}$ values of geraniol, citral, nerol, and geranyl acetate were 151, 224, 452, and $1,214{\mu}g\;mL^{-1}$, respectively. In greenhouse and field experiments, foliar application of palmarosa essential oil at the level of $80kg\;ha^{-1}$ controlled weeds effectively. Overall results of this study showed that the herbicidal activity of palmarosa essential oil could be due to geraniol and citral which had lower $GR_{50}$ values.

• Weed & Turfgrass Science
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• v.1 no.4
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• pp.44-49
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• 2012

The objective of this study was to know the herbicidal activity of the essential oil from amyris (Amyris balsamifera). In a seed bioassay experiment, the amyris essential oil inhibited the growth of rapeseed (Brassica napus) by fifty percent at 8.8 ${\mu}g\;g^{-1}$. And in a greenhouse experiment, sorghum, barnyard grass and Indian jointvetch, which was applied in above-ground parts, with the amyris essential oil at 4,000 ${\mu}g\;ml^{-1}$ showed visual injuries of 90, 70, and 70, respectively (0, no damage; 100, total damage). However, soil application of the essential oil did not show such herbicidal injuries. In a field experiment, foliar application of the amyris essential oil at 5% controlled effectively weeds such as barnyardgrass, shepherd's purse, and clover in 24 hours. Our results indicated that the amyris essential oil had herbicidal activity. To understand the composition of the amyris essential oil, the oil was analyzed by gas chromatography-mass spectometry with solid-phase micro-extraction apparatus. There were 15 organic chemicals in the oil and the major constituents were calarene, elemol, ${\gamma}$-eudesmol, curcumene, ${\beta}$-sesquiphellandrene, zingiberene, selina-3,7(11)-diene, 1,3-diisopropenyl-6-methyl-cyclohexene, ${\beta}$-bisabolene, and ${\beta}$-maaliene. Overall results suggest that the amyris essential oil had a herbicidal activity with fast, contact, and non-selective mechanism.

• Korean Journal of Food Science and Technology
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• v.32 no.6
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• pp.1409-1413
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• 2000

The seeds of Coix lachryma-jobi L. var. ma-yuen(yullmoo) were investigated for the free radical scavenging and mushroom tyrosinase inhibitory activities. Brown yullmoo, which contains bran in the seed, has also been evaluated for comparison. After partitioning of the total methanol extracts of yullmoo and brown yullmoo, each organic layer exhibited mild or potent dose-dependent inhibition(about 20-80%) on 1,1-diphenyl picryl hydrazyl(DPPH) free radical with the concentration of $300\;{\mu}g/ml$ to $800\;{\mu}g/ml$. n-Butanol fraction of yullmoo showed the most potent scavenging effect on DPPH free radical. $IC_{50}$ of n-butanol fraction was $423\;{\mu}g/ml$, about six to seven fold higher concentration than standard BHT at the same inhibition rate. As for the tyrosinase inhibitory activity, all of the fractions including the methanol extract exhibited the similar activities even after partitioning. The chloroform fraction of brown yullmoo was found to show the most potent inhibitory activity with an $IC_{50}$ of $321.5\;{\mu}g/ml$.

• Journal of agriculture & life science
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• v.44 no.3
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• pp.31-40
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• 2010

This study was carried out to offer a basis data for conservation and application of effective management of Camellia japonica stand in Hakdong, Geoje Island. Field survey was conducted at C. japonica stand, mixed stand, Chamaecyparis obtusa plantation, and Pinus thunbergii stand. Importance value of C. japonica at tree layer was highest in C. japonica stand and mixed stand, and that of C. obtusa and P. thunbergii were highest in C. obtusa plantation and P. thunbergii stand, respectively. At subtree layer, C. japonica, Callicarpa dichotoma, Neolitses serices, and Styrax japonica had the highest importance value in C. japonica stand, mixed stand, C. obtusa plantation, and P. thunbergii stand, respectively. The species diversity ranged from 0.121 to 1.589 in C. japonica stand, 0.543 to 1.540 in mixed stand, 0.276 to 1.321 in C. obtusa plantation, and 0.764 to 1.523 in P. thunbergii stand, respectively. Soil pH was 5.72 in C. japonica stand, 5.26 in mixed stand, 5.21 in C. obtusa plantation, and 5.32 in P. thunbergii stand. The content of organic matter and total N were 5.77, 0.48% in C. japonica stand, 4.41, 0.30% in mixed stand, 3.28, 0.33% in C. obtusa plantation, and 5.32, 0.28% in P. thunbergii stand.

• Journal of agriculture & life science
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• v.44 no.6
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• pp.27-37
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• 2010

This study was carried out to offer the basic information on ecological succession of evergreen broad-leaved forest through understanding of ecological characteristics of forest community by distance from Camellia japonica stand. Importance value of C. japonica at tree layer was highest in site I and those of Pinus densiflora and P. thunbergii were highest in site II, III and IV. At subtree layer, the importance value of C. japonica was highest in site I while Neolitsea sericea and Styrax japonica had the highest importance value in site II, III, and IV. In all sites, species diversity ranged from 0.121 to 0.515 and 1.112 to 1.589 at tree layer and subtree layer respectively. Evenness ranged from 0.811 to 0.930 at subtree layer, 0.796 to 0.913 at shrub layer and 0.155 to 0.727 at tree layer, this indicates that distribution pattern by species is more uniform at subtree and shrub layer than at tree layer. Soil pH was highest as 5.72 at site I. Contents of total N, organic matter and available P were higher at site I than other sites.

• International Journal of Industrial Entomology and Biomaterials
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• v.45 no.1
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• pp.35-41
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• 2022

Mulberry is a hardy, perennial, deep-rooted plant capable of thriving under diverse agroclimatic conditions. The selection of suitable land and appropriate variety can help the sustainable mulberry field. However, no conclusive and comprehensive investigation has been conducted on the mulberry soil properties and nutritional composition of mulberry cultivars from Korea local areas in previous studies. In our study, soil properties and mulberry leaf components of Korea local mulberry farms were briefly investigated. In result, the soil organic matter (OM) content was significantly high in Buan (6.81%) and Jangseong (6.14%). In contrast, available phosphate (P₂O₅) was different in each local area. To investigate relationship between soil property and nutritive component of mulberry leaf, Cheongil leaf samples from 8 local areas were analyzed. Among the macrominerals (K⁺, Ca²⁺, Na⁺, and Mg²⁺), the concentration of K varied from (1884±9.36) mg/100 g to (2685±11.5) mg/100 g. The potassium (K⁺) of Cheongil leaf in Sangju was the highest at 2685 mg/100 g. Besides macrominerals, flavonoids, total dietary fiber contents and moisture of Cheongil leaf samples were studied in the 8 local areas. In terms of these contents, the variation was largely depending on the local areas. This study provides a possible industrial use of mulberry, and holds promise to enhance the overall profitability of sericulture.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.37 no.2
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• pp.209-215
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• 1992

Different from 'Seyokwiryang' (歲易爲良 : fallowing as the best method) which was an agricultural technique of ancient China, fertilization of rice fields was already practiced in the end of Koryo age in Korea. 'Bunjongbeob'(糞種法 : fertilizer applicating method on seed) or 'Bunkwabeob' (糞科法 : fertilizer applicating method on each plant) was practiced before green manure of bean crops and 'Bunjeonbeob'(糞田法 : fertilizer practicing method on fields) were done. In the 15th century 'Dojeonbunjeonbeob'(稻田糞田法 : fertilizer applicating method on paddy) in 'Jikseol' was divided the materials to be used into the soil brought from another place, trees, grasses, and the manure. Also, it discribed the fertilization between first plowing and the second, and proper fertilization for particular soil conditions. In case of transplanting techniques, the fertilization practices were specified into nursery and rice fields, and restoration of organic matter was systemized by plowing for cultivation in the reclaimed areas. In the 17th century, through 'Jikseolbo'($\ulcorner$直說補$\lrcorner$), the habitual practice of Kyungsang province was systemized and 'Bunyangsool'(糞壤術 : technique of fertilization) of 'Jodoangkicheo' (早稻秧基處 : rearing fields of early-ripening rice) was completed. Specific things was the manufacturing and utilizing techniques of 'Bunhoe'(糞灰 : mixture of manure and ash), 'Yohoe'(尿灰 : mixture of urine and ash), and additional fertilizers. In the 18 to 19th century, the materials of fertilization were greatly enlarged to recover the waste lands and to support the reinforcement of soil fertility for increasing the system of two cropping a year. Also, 'Jeobunbeob'(貯糞法 : method of manure storage) and additional fertilization were emphasized, and use of wagons for it was emphasized to improve the theory of fertilization and working efficiency. As mentioned above, limitation of fertilizing materials was conquered by 'Dojeonbunyang'(稻田糞壤 : techniques of practicing fertilizers in paddy) and the system of additional fertilization was established. The fertilization methods were improved with 'Jeobunbeob' due to the theory and recognition necessary for high rates of fertilizers.

• Journal of Food Hygiene and Safety
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• v.22 no.4
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• pp.359-364
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• 2007

This study was conducted to determine the optimum condition of extraction and antioxidant activity of ethanol extracts of Epimedium koreanum Nakai based on the icariin quantity. Also, further organic solvent fractions of hexane, chloroform, ethyl acetate and butanol were obtained from the ethanol extract of Epimedium koreanum Nakai at different temperatures. Total ethanol extraction yield of wild grape seed ranged from 11.8% to 39.3% depending on the concentration of icariin as well as different ethanol concentration, extraction temperature and time condition. Among different extraction temperatures and time, the highest extraction yield of 39.3% was obtained at 70% ethanol for 3 hour at $50^{\circ}C$ in the sample containing the 0.596% icariin (KE9412). In the meantime, the strongest free radical scavenging effect $(RC_{50})$ with $18.9{\mu}g/mL$ in the KE9412 sample was observed in 70% ethanol extract of Epimedium koreanum Nakai extracted for 7 hour at $70^{\circ}C$, while $RC_{50}$ with $35.2{\mu}g/mL$ was observed in the KE9405 (0.20% icariin content) sample at same condition. Also, antioxidant activity of ethanol extracts of Epimedium koreanum Nakai increased as icariin concentration increased. Among each fraction obtained from organic solvents, butanol fraction was found to have the strongest $RC_{50}\;(39.2{\mu}g/mL)$ and followed by ethylacetate $(49.0{\mu}g/mL)$, water $(118.8{\mu}g/mL)$, ethylacetate $(119.8{\mu}g/mL)$, and chloroform fraction $(138.5{\mu}g/mL)$ respectively.

• Applied Biological Chemistry
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• v.15 no.2
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• pp.169-173
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• 1972

In five varietes of Citrus junos sieb grown in different area in Korea, the general components, total acids and inorganic components were calculated and compared with one other. In the orchard soils, the physical and chemical properties were studied. The results are summarized as follow: 1. Generally, the rind was weighter than tile flesh compared with the other fruits and the proportion of the rind was 49%. 2. Total contents of organic acids in rind and flesh were 12.29me and 39.79me respectively. 3. The order of the contents of inorganic components in the flesh and rind was $CaO>K_2O>MgO>P_2O_5>SO_4$ 4. The contents of crude protein and crude fat were increased with those of MgO and $SO_4$ in fruits. 5. The quantity of protein in the soil seed to influence greatly in rind formation not only in citrus fruits but also Citrus junos sieb. 6. In growing Citrus junos sieb, C.L. seemed to he the most adequate soil. 7. The pH range of the soil was from 5.05 to 7.20 generally. 8. The contents of crude protein and crude fat in citrus fruits seemed to be increased with those of organic material and total-nitrogen in the soil.

• Korean Journal of Organic Agriculture
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• v.23 no.3
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• pp.549-565
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• 2015

This study was conducted to investigate the growth characteristics and functional materials of baby vegetables as affected by different LEDs and luminous intensity at Anseongsi, Gyeonggi Province, in 2014. Test crops were beet, chicory, spinach, red leaf lettuce, crown daisy and red mustard purchased from the seed company of Dongbu Hannong and Jinheung. Growth characteristics were measured and the content of functional materials was analyzed 40 days after seeding at plug plate. Treatment of Red+Blue (4:1) at $150{\mu}mol\;m^{-2}s^{-1}$ luminous intensity showed the highest number of leaves in five baby vegetables of beet, chicory, red leaf lettuce, crown daisy and red mustard. The highest shoot length of chicory, spinach, red leaf lettuce, crown daisy and red mustard was obtained from the treatment of Red+Blue (4:1) at $150{\mu}mol\;m^{-2}s^{-1}$ luminous intensity. Fresh weight and dry weight of all six baby vegetables were the highest in treatment of Red+Blue (4:1) at $150{\mu}mol\;m^{-2}s^{-1}$ luminous intensity. Content of chlorophyll a and chlorophyll b of spinach, red leaf lettuce and red mustard showed the highest in Fluorescent lamp at $150{\mu}mol\;m^{-2}s^{-1}$ luminous intensity whereas other crops did not show definite trend under different LEDs lights and luminous intensity. The highest total content of anthocyanins and polyphenol were obtained from the treatment of Red+Blue (4:1) at $150{\mu}mol\;m^{-2}s^{-1}$ luminous intensity in all six baby vegetables. Free radical scavenging activity was highest in all six vegetable crops at $150{\mu}mol\;m^{-2}s^{-1}$ luminous intensity, but it was not different significantly between LEDs. As a result, the growth and the content of functional material of baby vegetables are generally to be increased in Red+Blue (4:1) at $150{\mu}mol\;m^{-2}s^{-1}$ luminous intensity. Mixed light of Red+Blue is thought to give good effect on the growth and the content of functional material in baby vegetable crops. Because there are many differences in regard of LED lights, crop varieties, cultivation and experimental methods in their impact on the growth and functional materials of baby vegetables among researchers, it is considered that a more precise studies are needed for the crop responses to LED light and luminous intensity.