• Korean Journal of Weed Science
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• v.11 no.3
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• pp.224-228
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• 1991

This study was carried to know factors affecting emergence of major upland weeds in soil in order to get basic information on weed control methods. Firthy eight percent of weed seeds were distributed within soil surface to 10cm in soil and 2% of weed seeds were observed in 40~50cm soil layer in field. As planting depth was deeper, emergence of weeds became poor. However Capsella bursa-pastoris can emerge at soil surface. Amaranthus retroflexus, Amaranthus lividus, Porturaca oleracea, Chenopodium album, Solanum nigrum upto 3cm, Eleusine indica, Echinochloa crus-galli, Setaria viridis, Digitaria sanguinalis upto 7cm. Emergence of weeds was very poor in very acid soil but good in soil pH 5.5~6.0. However emergence of weed was not affected by pH 3.5~4.0 or above. Emergence of E. indica, C. bursa-pastoris, A. retroflexus, A. lividus, C. album, E. crus-galli, Solanum nigrum, and S. viridis was good in loam soil and P. oleranea, D. sanguinalis in sandy loam soil. Emergence of weed seeds was not affected by fertilization.

• Korean Journal of Weed Science
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• v.8 no.3
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• pp.283-290
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• 1988

This study was conducted to clarify the identification of phytotoxic compounds from 5 upland weeds which had been collected at their maturity age in the field of Kyungpook province, Korea. 5 weed species including Stellaria aquatica strongly inhibited the lettuce seed germination. These 5 species were Amaranthus lividus, Stellaria aquatica, Achyranthes japonica, Polygonum perfoliata and Galinsoga ciliata. the degree of inhibitory effects according to various solvent extracts such as ethanol, aceton, chloroform and ether was different as species. In total phenol and diphenol content G. ciliata had largest amount of total phenol with 2.75mg/g, P. perfoliata 1.8mg/g, S. aquatica 1.7mg/g, A. lividus 1.28mg/g, A. japonica 1.27mg/g respectively. A. lividus had much amount of p-cresol, hydroquinone, ferulic, caffeic, p-cl-benzoic and p-coumaric in order. S. aquatica, A. japonica, P. perfoliata and G. ciliata had a large quantity of ferulic, caffeic, 7-OH-coumarin and protocatechuic acids in common. The amount of fatty acids was existed 8.49mg/g in S. aquatica, 7.14mg/g in A. japonica, 7.10mg/g in G. ciliata, 5.49mg/g in P. perfoliata and 4.2mg/g in A. lividus respectively. Most of 4 weeds except G. ciliata had much oxalic acid to the extent of 14-22mg/g. however it appeared that G. ciliata had much quantity of feruic and citric acids.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.4
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• pp.480-486
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• 2012

To evaluate of biological activity of Chambirum ($Amaranthus$ $lividus$) $in$ $vitro$ and $in$ $vivo$, we investigated the free radical scavenging activity of its extracts $in$ $vitro$ and the effect of lyophilized powder on the serum lipid profile of rats fed cholesterol. ABTS, DPPH, and NO radical scavenging activities were tested from water and 80% ethanol extracts of Chambirum, and biological activities of the ethanol extracts were significantly higher than the water extracts. The total lipid and total cholesterol content of serum, atherogenic index (AI), and cardiac risk factor (CRF) were decreased significantly for the groups fed with a 5% and 10% supplement of Chambirum powder (HCA1 and HCA2) in comparison with the group fed cholesterol (HC). Triglyceride content decreased drastically in the HCA2 group, while its content was not decreased in the other group. HDL-cholesterol content was elevated in the HCA1 and HCA2 groups, but was not significantly different to the supplemented amount of Chambirum powder. GPT and ${\gamma}$-GTP activities were decreased significantly in the groups fed with Chambirum powder compared to the HC group. And the content of the lipid peroxide level was the same trend. Therefore, these results give evidence that Chambirum might be useful in the control of induced disorders by dietary cholesterol and/or lipids.

• The Korean Journal of Pesticide Science
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• v.10 no.4
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• pp.351-358
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• 2006

This study was conducted to evaluate herbicidal properties of picolinafen in terms of crop safety, weed control spectrum, application window, residual efficacy and resistant weed control. Herbicidal phytotoxicity of picolinafen to wheat and barley was greatest when applied at 0 days after sowing (DAS), but decreased significantly as plant growth advanced. Picolinafen showed greater activity against broadleaved weeds than grass weeds. Picolinafen showed highest activity when it was applied at early post emergence timing (5 to 15 DAS), and showed significantly decreased activity at 20 DAS application. The $LT_{50}$ values (the period from application required for residual control by 50%) was 9.3 and 6.5 days against Digitaria ciliaris and Brasica naus at 60 g ai $ha^{-1}$, respectively. Picolinafen showed similar activities against both triazine resistant and sensitive Amaranthus retroflexus. Collectively, picolinafen appeared to have a good fitness to control resistant broad leaved weeds control by early post emergence application.

• Weed & Turfgrass Science
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• v.1 no.4
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• pp.38-43
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• 2012

This study was conducted to predict the yield response of red pepper and to determine the economic weed threshold levels for red pepper cultivation field from competition with the most serious weeds, Amaranthus patulus and Digitaria ciliaris in Youngyang of Korea. Crop yield as a function of weed density was predicted by using a rectangular hyperbola, and their economic threshold levels were determined by using the equation developed by Cousens (1987). The red pepper yield loss models of weeds were predicted as y=304.7/(1+0.063x), $R^2$=0.967 in D. ciliaris and y=281.3/(1+0.1723x), $R^2$=0.952 in A. patulus. Economic thresholds calculated using Cousens' equation were negatively related with the competitiveness of weed. Economic thresholds of each weed were calculated as 18.2 plant $100m^{-2}$ in D ciliaris, and 7.2 plant $100m^{-2}$ in A. patulus.

• Korean Journal of Veterinary Research
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• v.26 no.1
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• pp.139-147
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• 1986

In order to clarify the pathogenesis of perirenal edema, pigs and rabbits were administered with oxalate and nitrate, with oxalate nitrate and glycolic acid, with oxalate, nitrate and ascorbic acid and with oxalate, nitrate and calcium, respectively. The results obtained are summarized as follows; The pigs and rabbits administered with oxalate and nitrate with oxalate, nitrate and glycolic acid and with oxalate, nitrate and ascorbic acid, respectively, were not showed perirenal edema despite of observing the abundant oxalate crystals in the proximal convoluted tubles. But pigs and rabbits administered with oxalate, nitrate and calcium were histopathologically showed perirenal edema similar to those of pigs fed Amaranthus retroflexus. Therefore, author considered that oxalate, nitrate and calcium are main factors to cause perirenal edema. It was regarded that perirenal edema in pigs was caused by the reciprocal reactions of those materials including oxalate, nitrate and calcium which may produce vascular damage, decreased osmotic pressure by hypoproteinemia and increased vascular permeability in kidney, rather than the mechanical obstructions by the oxalate crystals in the proximal convoluted tubule.

• Natural Product Sciences
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• v.9 no.4
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• pp.299-303
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• 2003

For the screening of inhibitors of sterol biosynthesis from natural products, a simple and rapid assay method was developed using recombinant yeast carrying human lanosterol synthase, main target of this assay method. Sterol biosynthesis inhibition activity was monitored only by the inhibition of growth of the recombinant yeast. By changing the substrate, this assay method can figure out which step is inhibited in the sterol biosynthesis by the test material. With this assay method total 102 plant samples were screened for their inhibitory activity of sterol biosynthesis. Among plant water extracts screened, 11 plant samples showed inhibitory activity on sterol biosynthesis in ergosterol (-) medium. For selection of the specific inhibitory materials, 11 plant samples were reassayed in ergosterol (+) medium. After all 5 plant samples, Abutilon avicennae Gaertn. (stem), Alnus japonica Steud. (stem), Amaranthus mangostanus L. (aerial part), Philadelphus schrenckii Pupr. (leaf) and Pimpinelia brachycarpa Nakai (aerial part), showed specific inhibitory activity.

• Natural Product Sciences
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• v.22 no.3
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• pp.168-174
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• 2016

Anti-melanogenic effects of amaranth (AT), one of the key source of squalene, were investigated in melanocytes. Amaranth seed powder was extracted with water and melan-a cells were treated with various concentrations of AT. By using HPLC, content of myo-inositol, one of potential active components, was measured in the crude extract of AT.AT reduced the melanin content in melan-a melanocytes and down-regulated melanogenic enzyme activity such as tyrosinase, TRP-1 and TRP-2. By regulating melanogenic enzyme activity, AT may be a potential natural source for whitening agent. Myo-inositol was detected in AT by HPLC and may be one of the active compounds from AT involved in the regulation of anti-melanogenesis. In this study, we demonstrated that AT has anti-melanogenesis properties. This new function of amaranth may be useful in the development of new skin-whitening products and its value as food.

• Journal of The Korean Society of Grassland and Forage Science
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• v.21 no.2
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• pp.97-102
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• 2001

This study was carried out to survey the weed distributions in 6 areas(Suwon, Seonghwan, Seosan, Taekwanryeong, Namwon and Yeongam) and to investigate the ecological characteristics of exotic weeds from 1997 to 1999. Total 44 species in 15 families of exotic weds were observed in grassland and forage crop field. Among them 4 species in 1 family were monocotyledonous and 40 species in 14 families were dicotyledonous weeds. Most common species among exotic weeds examined in this study were Rumex acetosella, Rumex crispus. Chenopodium album, Abutilon theophrasti, Amaranthus retroflexus, Polygonum orientale etc. Inedible weeds with hairs, prickles, fetor or poison were Solanum carolinense Xanthium strumarium, Datura stramnium, Erechtites hieracifolia, Anthemis cotula, Phytolaca americana etc. The relative density of Phytolaca americana increased with decreament of soil pH and content of available phosphate, and that of Solanum carolinense increased with decreament of soil pH and increament of available phosphate. Most of exotic weed seeds germinated well under light condition with $25~30^{\circ}C$, and some of those were hard or dormant seed.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.20 no.5
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• pp.15-41
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• 2017

The purpose of this study is to present the basic data for conservation of forest ecosystem by surveying and analysing the flora distributed in Nakdong-Jeongmaek Mountains, Korea. The numbers of flora were 901 taxa including 116 families, 433 genera, 790 species, 4 subspecies, 90 varieties, 15 forms and 2 hybrids. The threatened species was Pedicularis ishidoyana. The rare plants were 33 taxa including Pseudostellaria sylvatica, Cimicifuga heracleifolia var. bifida, Isopyrum mandshuricum, Paeonia japonica, Syringa patula var. kamibayshii, Lilium distichum, Iris odaesanensis and so forth. The Korean endemic plants were 35 taxa including Salix koriyanagi, Thalictrum actaefolium var. brevistylum, Corydalis maculata, Lespedeza maritima, Cirsium setidens, Carex okamotoi and so forth. The specific plants by floristic region were 155 taxa including 55 taxa of grade I, 41 taxa of grade II, 36 taxa of grade III, 18 taxa of grade IV and 5 taxa of grade V. The naturalized plants were 62 taxa including Rumex obtusifolius, Amaranthus lividus, Medicago sativa, Geranium carolinianum, Malva sylvestris var. mauritiana, Foeniculum vulgare, Sonchus oleraceus, Tradescantia reflexa and so forth. The invasive alien plants were 5 taxa including Rumex acetocella, Solanum carolinense, Ambrosia artemisiifolia, Aster pilosus and Lactuca scariola.