• Journal of Life Science
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• v.23 no.11
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• pp.1360-1364
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• 2013

Petasin extracted from Petasites japonicus leaves has been well known to be effective in the treatment of allergic asthma. This study was carried out to optimize the extraction process of petasin from P. japonicus leaves by response surface methodology (RSM). The dried powder of P. japonicus leaves was extracted at ethanol concentrations ranging from 40% to 80%, extraction rpm ranging from 125 rpm to 225 rpm, and extraction time ranging from 1 to 3 hours. The effects of the extraction conditions on the dry yield and petasin content of the extracts were investigated using a second-order Box-Behnken design. The petasin content was significantly affected by ethanol concentration, extraction rpm, and extraction time, tending to increase more with increasing ethanol concentration. The optimum condition for petasin extraction from Petasites japonicus leaves was 79.92% in ethanol concentration, 178.10 rpm in extraction rpm, and 2.06 hours in extraction time, respectively.

• Korean Journal of Organic Agriculture
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• v.7 no.2
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• pp.89-97
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• 1999

Through manifestation of the principles of commodity production spatial sharing of labour can be observed in the agriculture as well as in cattle production. Better adjustment of the production structure to the environment factors brings higher yields and more effective production. In being able to maximize the profit the entrepreneurs opt for producing output that closely matches to their featuring conditions. In contrary to the relatively high "mobility" of crop production animal husbandry and within this cattle production - as known - is strictly chained to forage production. On the basis of our economic research and as a result of multivariable analysis(factor analysis) it can be concluded that two variable groups(factors) are highly dominant in organizing profitable cattle production. First of them is the crop site factor (indicated by gold crown value), the second is the forage production feature(forage and grassland area and the yield of them). During recent years the weight of environmental factors suffered from devaluation. As a result of the central economic administration differentiating effects were suppressed and the chances of equalizing concepts strengthened. The outcome can be observed even today. In the regions, for example, being predominantly suitable for grass and forage cropping the milk and slaughter cattle production decreased. The same is ture for com and pig production regions. Unexploitment of local environmental features can be observed mainly in grassland management. Branches being potential user of grasslands hardly take them into consideration. Main method of rational use of grasslands is pasturing. Presence of pastures and the usage of them through cattle production is highly important not only for profitable production but also for maintaining ecological stability.

• Journal of fish pathology
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• v.26 no.3
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• pp.139-148
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• 2013

The genus Polydora(Polychaeta, Spionidae) includes many species well known for their activity as borers. They often become harmful invaders by reducing the growth rate and meat yield of, or inducing the mortality of commercially important mollusck, abalone, Haiotis discus hannai. In 2012, the frequency of the Polydora was observed with 5~99% in live abalone and 5.3~70.3% in dead abalone shells of abalone sea-caged aquaculture system, Korea. There are many nacreous blister in the ventral margin and inner of the infestated abalone by abalone in response to the Polydora. A worm bored two holes in the shell and come in and out for ingestion the organic matters. They are more than 40 mm in length and had outstanding palps with black bars, disc form pygidium and 4 eyespots. This is the first record for the statue of Polydora infestation of sea-caged cultured abalone, Haliotis discus hannai in Korea.

• Korean journal of food and cookery science
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• v.19 no.5
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• pp.616-623
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• 2003

Waxy barley brans were collected during the pearling process. The extraction of $\beta$-glucan from barley bran was effected by the extraction conditions. The $\beta$-glucan content increased with temperature, but not with pH. The highest yield, 6.5%, was achieved at pH 7.0 and 55$^{\circ}C$. At pH 10 and 45$^{\circ}C$, 48.5% of the $\beta$-glucan in barley bran was recovered in the gum product, with 54.6% purity. The protein and starch contaminations were high, reaching 13.6 and 23.7%, respectively. The $\beta$-glucan content was greatest in the subaleurone and aleurone regions (bran fractions 1, 2, 3 and 4), and declined considerably toward the inner layers. A monosaccharide analysis of the purified, $\beta$-glucan, from bran fractions 1, 2, 3 and 4, indicated that glucose constituted the majority of the gum. The small amounts of the arabinose and xylose found in the gum may indicate the presence of arabinoxylans as minor constituents. The molecular weights of the $\beta$-glucans isolated from bran fractions 1,2 and 3 were found to be 4.09${\times}$10$^{5}$ ∼-4.41${\times}$10$^{5}$ . The major glycosidic linkages of the $\beta$-glucans demonstrated the presence of 2, 4, 6-Me-Glc and 2, 3, 6-Me-Glc. When flow behaviors of barley bran $\beta$-glucan were examined, $\beta$-glucan exhibited pseudoplastic fluid properties.

• Korean Journal of Food Science and Technology
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• v.16 no.3
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• pp.368-374
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• 1984

The purification of 5'-riboncleotide using ion exchange resins has been studied and the optimum conditions were determined. The amount used of Amberlite IR120 ion exchange resin in 2nd resin tower could be reduced up to 20% by pretreating the hydrolyzed RNA solution in 1st resin tower. The amount used of regenerant could be also reduced up to 20% by desalting the hydrolyzed RNA solution in the 1st tower, because the desalted solution eluted easily by the water in the 2nd tower. The crystal obtained in this experiment was the mixed-crystals of $5'-IMP.Na_2\;and\;5'-GMP.Na_2$. The crystallization of the complexes formed from $5'-IMP.Na_2\;and\;5'-GMP.Na_2$ gave the best result at pH 7.6. The yield of crystal complexes formed from $5'-IMP.Na_2\;and\;5'-GMP.Na_2$ was obtained higher in high MeOH concentration. However, in higher than 60% MeOH concentration the products was amorphous. The higher content of MeOH for the crystallization of the product gave the smaller value of $5'-IMP.Na_{2}/5'-GMP.Na_2$.

• Resources Recycling
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• v.29 no.5
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• pp.28-37
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• 2020

In this study, the effect of precipitation temperature, ammonium chloride amount and addition method, vanadium and sodium hydroxide content of the solution on the precipitation of ammonium metavanadate were examined by using the sodium vanadate(NaVO₃) solution in alkali region as a starting material. As the pH of solution decreased, the addition amount of ammonium chloride and the vanadium content of the solution increased, the precipitation rate of ammonium metavanadate increased. In this research condition, the basic conditions for obtaining more than 90% of precipitation yield were 10,000mg/L of vanadium content, 2equivalents of ammonium chloride addition, room temperature, and 2 hours of precipitation time. The size of precipitated particles decreased with increasing precipitation rate. Especially when liquid ammonium chloride was injected into the solution, the precipitation rate was the slowest and the particle size of the precipitate was the largest. After the primary precipitation by adding ammonium chloride as a solid, the secondary precipitation was carried out by adding new reactants. At this time, the precipitation with added ammonium chloride solid was not affected by the precipitates present in the solution. However, when liquid ammonium chloride was added, new precipitate was deposited on the surface of the precipitate present in the solution, increasing its size. Due to the difference in ammonium metavanadate solubility to temperature, the precipitation temperature at the vanadium content of 10,000mg/L in the solution affected the precipitation rate of ammonium metavanadate and the precipitation temperature did not affect the precipitation rate at a high concentration of more than 30,000mg/L vanadium content in the solution.

• Journal of Korean Society of Forest Science
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• v.73 no.1
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• pp.33-42
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• 1986

This study was carried out to investigate the optimum conditions for isolation and culture of mesophyll protoplasts from Populus alba ${\times}$ P. glandulosa. The results obtained from the experiments are as follows; 1) The suitable concentration of BAP for shoot multiplication was 0.4 mg/l. 2) High yield and viability of isolated protoplasts were obtained by our high enzyme-short time incubation method. 3) Optimum enzyme concentrations for mesophyll protoplast isolation were Cellulase 2%, Macerozyme 0.8%, Hemicellulase 1.2%, Driselase 2%, and Pectolyase Y-23 0.05%. 4) 0.6M mannitol in enzyme solution was the most effective for protoplast isolation and viability. 5) The most adequate pH level of enzyme solution was pH 5.6. 6) The effect of DTT and MES buffer was significant. 7) For protoplast purification, 0.6M sucrose was the most proper concentration. 8) The adding effect of Dextran T40 in floating solution was important. 9) The mesophyll protoplasts isolated through our high enzyme-short time incubation method revealed successful response to culture condition over 3 weeks of culture.

• Journal of Radiation Industry
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• v.6 no.2
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• pp.189-197
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• 2012

This study was carried out to develop the improved useful mutants for yield or composition of stevia plants using the gamma ray or chemical mutagens treatments. The seeds of stevia 'Suwon No. 11' were irradiated up to 400 Gy of gamma ray. Chemical mutagens were treated on the seeds of the 'Suwon No. 11' using 0.07% colchicine, 10 mM sodium azide, or 10 mM NMU for various durations. The germination rate, and shoot and root growth of seedling were estimated at 30 days after gamma ray irradiation or chemical mutagen treatment, and the plant height, the number of branches, and leaf length and width were examined at 3 months after mutagenesis treatments. In the case of gamma ray treatments, the germination rate and early-stage growth were decreased as the increase of radiation dose, and the 50% lethal dose was found to be 200 Gy. the plant height was decreased as the increase of radiation dose, while the number of branches per plant and leaf length were increased. Leaf shape was modified to the relatively longer one compared to the control, which was identified more apparently at the treatments of higher than 150 Gy. In the treatment of chemical mutagens, the rate of germination and survival were decreased as the increase of incubation time. The 50% lethal dose for germination rate were identified as the conditions of the 15 hours incubation in 0.07% colchicine, the 4 hrs in 10 mM sodium azide, and the 2 hrs in 10 mM NMU, in the three chemical mutagens treatments. Chemical mutagens had no influence on shoot growth, while root growth was increased, especially as the incubation time was extended. The highest root growth occurred in the NMU treatment at 6 hrs incubation time. The plant height was decreased as the increase of incubation time in the chemical mutagens treatments. Among the chemical mutagens, NMU was the most effective to induce the mutants with long-shaped or the least lobed leaves.

• Journal of agriculture & life science
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• v.46 no.1
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• pp.163-176
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• 2012

TTo increase productivity of a strong extracellular alkaline protease (BCAP), stable strains of Bacillus clausii I-52 carrying another copy of BCAP gene in the chromosome were developed. Integrative vector, pHPS9-fuBCAP carrying BCAP promoter, ribosome binding site, signal sequence and active protease gene was constructed and transferred into B. clausii I-52, and integration of the constructed plasmid into chromosome was identified by PCR. An investigation was carried out on BCAP production by B. clausii I-52 and transformant C5 showing the highest relative activity of alkaline protease using submerged fermentation. Maximum enzyme activity was produced when cells were grown under the submerged fermentation conditions at $37^{\circ}C$ for 48 h with an aeration rate of 1 vvm and agitation rate of 650 rpm in a optimized medium (soybean meal 2%, wheat flour 1%, sodium citrate 0.5%, $K_2HPO_4$ 0.4%, $Na_2HPO_4$ 0.1%, NaCl 0.4%, $MgSO_47H_2O$ 0.01%, $FeSO_47H_2O$ 0.05%, liquid maltose 2.5%, $Na_2CO_3$ 0.6%). A protease yield of approximately 134,670U/ml was achieved using an optimized media, which show an increase of approximately 1.6-fold compared to that of non-transformant (83,960 U/ml). When the stability of transformant C5 was examined, the integrated plasmid pHPS9-fuBCAP was detected in the transformant after cultivation for 8 days, suggesting that it maintained stably in the chromosomal DNA of transformant C5.

• FLOWER RESEARCH JOURNAL
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• v.19 no.2
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• pp.115-118
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• 2011

A light pink single freesia (Freesia hybrida Hort.) 'Bolero' was developed from a cross of breeding line ('Yellow Ballet' and 'Yellow Dream') and 'Sandra' followed by seedling and line selections at the National Institute of Horticultural and Herbal Science (NIHHS), Rural Development Administration (RDA) in 2007. Growth and flowering characteristic tests were conducted from 2003 to 2006. 'Bolero' has single type flower with light pink color (RHS, R55B). It has multiple florets, stable flower shape, upright leaves and stalks. The average cut flower yield of 'Bolero' observed in the greenhouse from 2005 to 2007 was 7.5 cuttings per plant. It has good production of cormlets and vigorous growth. 'Bolero' could be cultured under greenhouse conditions in Korea.