• Korean Journal of Medicinal Crop Science
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• v.9 no.2
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• pp.91-98
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• 2001

Scutellaria baicalensis G. was cultivated in plots of different soil textures which were sand loam(SL), loam(L) and clay loam(CL). Also three fertilizer conditions were used; non application (NA)treatment, rice straw manure(RSM) treatment and N-P-K, chemical fertilization(CF) treatment. The chemical-physical properties, such as organic matter, available phosphate, $K_2O$, CaO, clay contents and porosity ratio in CL plot with RSM application were the most proper in CL plot and RSM application for the culture of S. baicalensis plants. RSM had very high contents of total nitrogen, 2.25% and C/N ratios, 21.4. Thus the growth of shoot and root in loam plot with RSM treatment were greater compared to that of CL plot with NA treatment. Whereas, The highest baicalin, baicalein and wogonin contents in roots were found in CL plot with RSM treatment. There was significantly positive correlation between aerial and underground parts of plant, yield and contents of T-N, $K_2O$ but negatively correlated with the contents of baicalin, baicalein and wogonin in S. baicalensis roots.

• Korean Journal of Microbiology
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• v.51 no.2
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• pp.97-107
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• 2015

Wetlands constitute a transitional zone between terrestrial and aquatic ecosystems and have unique characteristics such as frequent inundation, inflow of nutrients from terrestrial ecosystems, presence of plants adapted to grow in water, and soil that is occasionally oxygen deficient due to saturation. These characteristics and the presence of vegetation determine physical and chemical properties that affect decomposition rates of organic matter (OM). Decomposition of OM is associated with activities of various extracellular enzymes (EE) produced by bacteria and fungi. Extracellular enzymes convert macromolecules to simple compounds such as labile organic carbon (C), nitrogen (N), phosphorus (P), and sulfur (S) that can be easily taken up by microbes and plants. Therefore, the enzymatic approach is helpful to understand the decomposition rates of OM and nutrient cycling in wetland soils. This paper reviews the physical and biogeochemical factors that regulate extracellular enzyme activities (EEa) in wetland soils, including those of ${\beta}$-glucosidase, ${\beta}$-N-acetylglucosaminidase, phosphatase, arylsulfatase, and phenol oxidase that decompose organic matter and release C, N, P, and S nutrients for microbial and plant growths. Effects of pH, water table, and particle size of OM on EEa were not significantly different among sites, whereas the influence of temperature on EEa varied depending on microbial acclimation to extreme temperatures. Addition of C, N, or P affected EEa differently depending on the nutrient state, C:N ratio, limiting factors, and types of enzymes of wetland soils. Substrate quality influenced EEa more significantly than did other factors. Also, drainage of wetland and increased temperature due to global climate change can stimulate phenol oxidase activity, and anthropogenic N deposition can enhance the hydrolytic EEa; these effects increase OM decomposition rates and emissions of $CO_2$ and $CH_4$ from wetland systems. The researches on the relationship between microbial structures and EE functions, and environmental factors controlling EEa can be helpful to manipulate wetland ecosystems for treating pollutants and to monitor wetland ecosystem services.

• Korean Journal of Environmental Agriculture
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• v.5 no.1
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• pp.48-54
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• 1986

Because of the drastic development of nuclear industries, the contamination of natural environments by the disposal of radioactive materials which are released from nuclear facilities have aroused a considerable concern in relation to agricultural practices. Therefore the present investigation, through pot experiment, was performed to find out the aspect of the uptake of $Sr^{90}$ by rice plants and its distribution in them in five different types(physicochemical and minerallogical properties) of paddy soils. The results obtained were as follows; 1) Visual toxic symptoms on the growth of rice plant due to treatment of $Sr^{90}$ up to $40{\mu}Ci/10㎏$ in a pot were not observed even though uptake of $Sr^{90}$ by rice plant was proportionally increased with the $Sr^{90}$ treatment. 2) Distribution of $Sr^{90}$ in the rice plant was the highest in the leaves (84.5%) followed in the order by stems (13.5%) and rough grain (2.0%). The ratio of $Sr^{90}$ to Ca was higher in the leaves (872) and stems (667) than in the rice grain (89). 3) $Sr^{90}$ absorption in the rice plant ranged $0.15{\sim}0.30%$ at harvesting time. Uptake of $Sr^{90}$ by rice plants decreased by the increase of soil pH and exchangeable canons in the soils, but $Sr^{90}$ uptake increased when nitrogen, organic matter and clay content in soil was high, and uptake of this nuclide in the rice plant was higher with low Illite and Vermiculite content in the soils.

• Journal of The Korean Society of Grassland and Forage Science
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• v.28 no.2
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• pp.139-154
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• 2008

The nearly 75% of animal feed materials used for livestock production are imported every year in Korea. Most of imported feed ingredients are concentrated feeds such as com, wheat, soybean, soybean meal, etc. and they are used as the source materials for the production of assorted feed. The imported concentrated feeds are high in nitrogen and phosphorus. Therefore, the consistent import of feed ingredients may cause an increase of nutrient deposit in our agricultural ecosystem. In the current review, it was discussed with the situation of the feed importation and its nutritional composition to evaluate the nutrient load by the imported feeds onto agricultural ecosystem. The nutrient load caused by imported feeds in agricultural environment was compared with the nutrient demand for crop production. The amounts of N, $P_2O_5\;and\;K_2O$ introduced by the imported fteds in Korea were 371, 140 and 143 Ktons. And, the N, $P_2O_5\;and\;K_2O$ loads excreted from imported feeds in livestock were 148, 84 and 86 Ktons of N, $P_2O_5\;and\;K_2O$ and These nutrient loads by the imported feeds are at the percentage of N 52%, $P_2O_5$ 52% and $K_2O$ 42% in the comparison of total nutrient amounts excreted from livestock animals in Korea. The 82.3% of nutrients excreted from livestock was recycled to crop land as compost and liquid fertilizer, and the others were discharged to river after water treatment processing or disposed to ocean. Also, passing through the recycling process far the production of compost and liquid fertilizer, the amount of nutrients was reduced by the ammonia vaporization of livestock feces and urine. Accordingly, N 81, $P_2O_5$ 74 and $K_2O$ 76 Ktons in the nutrients excreted from livestock were estimated to be utilized in the crop land. Consequently, it was estimated that 44, 48 and 69 Ktons of N, $P_2O_5\;and\;K_2O$ were taken up with crops in the consideration of the ratio of mineralization, and the amounts of leached or deposited N, $P_2O_5\;and\;K_2O$ in crop land were estimated to be 37, 27 and 7 Ktons, respectively. It is estimated that 12%, 34% and 48% of N, $P_2O_5\;and\;K_2O$ introduced by the imported feeds were used by crops, and 10%, 34% and 5% of N, $P_2O_5\;and\;K_2O$ were leached or deposited in agricultural ecosystem. Therefore, considering the leached and deposited amounts of N, $P_2O_5\;and\;K_2O$ originated from the imported feed ingredients, the consistent import of feeds may gradually increase the nutrient load onto agricultural ecosystem.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.35 no.5
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• pp.455-461
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• 2002

limiting nutrients for phytoplankton were determined by dissored inorganic nitrogen/phosphorous (DIN/DIP) in situ and algal bioassay experiment in the Seomjin River estuary during a study period from March 1999 to October 2001. DIN/DIP ranged from 14.7 to 681.1 during the study period. DIN/DIP was over 16 at the upper and middle estuarine region where salinity was lower than 25 psu and chlorophyll a concentration was high, probably indicating P-limitation in this region while the ratio was less than 16 at the high saline (> 25 psu) region, reflecting the supply of DIP from Gwangyang Bay and thereby indicating N-limitation at the lower estuarine region. These results suggested that the spatial distribution of DIN/DIP in the study region was controlled by the high supply of phosphate from Gwangyang Bay, the low input from Seomjin River and the active uptake by phytoplankton within the estuarine system. The bioassay experiments using Skeletonema costatum, Thalaasiosira rotula and in situ phytoplankton assemblage displayed relatively higher growth of phytoplankton in the P-added culture media, indicating P-limitation. This result was well consistent with the spatial distribution of inorganic nutrients. S. costatum showed a rapid adaptation to the low salinity compared to other phytoplankton species. This phenomenon seemed to account for the strong (> $90\%$ in total cell number) S. costatum bloom in autumn in this estuary. Moreover, although phytoplankton growth rate was higher in the P-added culture media at the end of culture experiment of in situ phytoplankton, the fast growth in the trace metal-added media at the beginning of the experiment suggested a possibility of limitation by other micro-nutrients such as trace metal and vitamin etc.

• Tuberculosis and Respiratory Diseases
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• v.46 no.4
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• pp.489-499
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• 1999

Background: The patient with bronchiectasis may have obstructive ventilatory impairment combined with mild restrictive ventilatory impairment due to fibrosis of surrounding lung parenchyme and pleural adhesions caused by chronic recurrent pulmonary infections. Since hyperinflation or emphysematous change can be occured in bronchiectasis, pulmonary functions such as lung volumes and diffusing capacity may also vary with associated emphysema. Methods: For the evaluation of lung volumes and diffusing capacity in bronchiectasis with respect to the anatomic types and severity of bronchiectasis, a total of 40 cases comprising 24 cases of tubular, and 16 cystic type of bronchiectasis were analyzed retrospectively. Correlation between lung functions and extent of bronchiectasis or associated emphysema detected in HRCT were also evaluated. Results: Vital capacity(VC) tended to decrease in cystic type than in tubular type. As the severity of bronchiectasis became serious, the VC were significantly reduced, whereas the total lung capacity(TLC), residual volume(RV) and its ratio to the total lung capacity(RV/TLC) had no significant difference. Lung clearance index(LCI) was significantly increased in cystic type than in tubular type, whereas the slope of phase III in single breath nitrogen curve($\triangle$N2/L) was not significantly changed regard to the type and severity of bronchiectasis. DLCO and DLCO/VA reflecting diffusing capacity were significantly decreased in cystic type and also as the severity of bronchiectasis became serious. The correlation coefficient of VC, DLCO and LCI with the extent of bronchiectasis were -0.322, -0.339 and 0.487, respectively, whereas other parameters were not significantly correlated with the extent of bronchiectasis. VC and DLCO correlated negatively with the extent of emphysema while RV, RV/TLC, LCI and $\triangle$N2/L correlated positively. Conclusion: These findings suggest that the reduction of VC and diffusing capacity or uneven distribution of inspired gas in bronchiectasis are related to both the extent of bronchiectasis and associated emphysema while increased residual volume be related to the extent of associated emphysema alone.

• The Korean Journal of Mycology
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• v.39 no.3
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• pp.164-170
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• 2011

Amanita hemibapha is a kind of mycorrhizal mushroom which has a relation with host plants and environmental factors. For the purpose of studying the relationship between environmental factors and mushrooms, in this study we conducted to investigate the soil physicochemical properties, the distribution of plants and the diversity of mushrooms in Gwangyang, Chungdo and Daegu. Soil texture in habitate of Amanita hemibapha was Sandy Loam and Sandy Clay Loam which contains a high rate of sand. Soil pH was approximately 5.0 in all study sites. Total nitrogen contents, C/N ratio and available phosphate($P_2O_5$) were the highest at the Chungdo. However, Gwangyang and Chungdo represent similar Cation Exchange Capacity(C.E.C) and Daegu has much less than other areas. Exchangeable cations, $Ca^{2+}$ content was higher at Gwangyang and Chungdo than Daegu and $Na^+$ content was the highest at Chungdo among three sites. Daegu has much $Mg^{2+}$ contents followed by Chungdo and Gwangyang. Interestingly, $K^+$ content listed in reverse order of $Mg^{2+}$ at Gwangyang, Chungdo and Daegu. The main woody plants in study sites are confirmed as Carpinus laxiflora, Quercus mongolica, Q. serrata and Pinus densiflora. Quercus species are found as a common species in three study sites. Lastly, 8 family and 12 species of mushrooms are emerged in Gwangyang, also 8 family and 12 species and 5 family and 10 species are found in Chungdo and Daegu, respectively. Amanita pantherina, Boletus edulis, Tylopilus felleus and Marasmius maximus, which found in study sites, are also kind of mycorrhizal mushroom same as A. hemibaph. By using correspondence analysis, Q. mongolica, Q. serrata, Q. variabilis and C. laxiflora are expected to as a host plant of A. hemibapha.

• Korean journal of food and cookery science
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• v.32 no.4
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• pp.390-399
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• 2016

Purpose: The objective of this study was to examine the effect of plant scale and cooking conditions on the quality characteristics of sausages during refrigerated storage. Methods: Sausages used in this study were classified into two groups: those submitted to $1^{st}$ cooked treatments and those submitted to $2^{nd}$ cooked treatments. The pH, volatile basic nitrogen (VBN), gas production ratio, and microorganisms were measured in triplicate. Results: The change of quality in the products was assessed every 7 days by measuring pH, VBN levels, total microbes, coliform bacteria, Escherichia coli, and pathogenic bacteria in the products. Pathogenic bacteria such as Staphylococcus aureus, Listeria monocytogenes, Clostridium perfringens, and E. coli were not detected in the sausages with $1^{st}$ cooked treatments. The results showed that the pH of the sausages decline as storage time increased. The pH value of the sausages with $2^{nd}$ cooked treatments changed gradually. VBN levels were generally lower in products with $2^{nd}$ cooked treatments than in those with $1^{st}$ cooked treatments, but they varied with the type of products. On the $35^{th}$ day, the number of total microbes ranged between 6.13-7.12 log CFU/g in products with $1^{st}$ cooked treatments and 3.44-6.92 log CFU/g in products with $2^{nd}$ cooked treatments, showing fewer bacteria in the latter products. Conclusions: $1^{st}$ cooked treatments were effective in microbial control, but $2^{nd}$ cooked treatments could prolong the shelf life of the sausages, indicating a need for differential management of each product.

• Ocean and Polar Research
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• v.32 no.3
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• pp.269-289
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• 2010

In Summer 2008, a multidisciplinary survey was conducted onboard R/V Haeyang 2000 to understand plankton response to the three distinct physico-chemical settings that developed in the Ulleung Basin of the East Sea. Baseline settings of hydrographic conditions included the presence of the thin (<20 m) Tsushima Surface Water (TSW) on top of the Tsushima Middle Water (TMW). It extends from the Korea Strait to $37^{\circ}N$ along the $130^{\circ}E$ and then turns offshore and encompasses the relatively saline (T>$26^{\circ}C$, S>33.7) Ulleung Warm Eddy surface water centered at $36.5^{\circ}N$ and $131^{\circ}E$. A relatively colder and saline water mass appeared off the southeastern coast of Korea. It was accompanied by higher nutrient and chlorophyll-a concentrations, suggesting a coastal upwelling. Most of the offshore surface waters support low phytoplankton biomass (0.3 mg chl-a $m^{-3}$). A much denser phytoplankton biomass (1-2.3 mg $m^{-3}$) accumulated at the subsurface layer between 20-50 m depth. The subsurface chlorophyll-a maximum (SCM) layer was closely related to the nutricline, suggesting an active growth of phytoplankton at depth. The SCM developed at shallow depth (20-30 m) near the coast and deepened offshore (50-60 m). A fucoxanthin/zeaxanthin ratio was high in coastal waters while it was low in offshore waters, which indicated that diatoms dominate coastal waters while cyanobacteria dominate offshore waters. The community structure and biomass of phytoplanktonare closely related to nitrogen availability. Zooplankton biomass was higher in the coastal region than in the offshore region while species richness showed an opposite trend. Zooplankton community structure retained a coastal/offshore contrast. These suggest that summer hydrography is a stable structure, lasting long enough to allow a hydrography-specific plankton community to evolve.

• Applied Biological Chemistry
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• v.29 no.3
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• pp.288-293
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• 1986

The washed fresh ginsengs packed with air, vaccum and nitrogen gas were irradiated at the levels of 1,2 and 3kGy gamma radiation and then stored at $4{\sim}5^{\circ}C$ for 90days to investigate the effects of gamma radiation on microbial inactivation, eelworm disinfestation and physicochemical changes. After a 90 day storage, $2{\sim}3kGy$ irradiated groups showed 20% of weight loss and 10% of rot while non-irradiated group 100% and 20% or more, respectively. Also the irradiated groups showed somewhat lower values of specific gravity, color density and hardness immediately after irradiation, thereafter higher value of them with storage time than those of non-irradiated group. The irradiation increased the yields of ginseng extract and crude saponins but no effects on the proximate composition and TLC and HPLC patterns of saponin. The food-borne microorganisms decreased in viable cell counts by $2{\sim}3$ log cycles with $2{\sim}3kGy$ radiation and the eelworms were completely disinfested with 1 kGy radiation.