• Journal of Wetlands Research
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• v.15 no.1
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• pp.71-78
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• 2013

An exceptional case of inhabitation of a Sphagnum sp. was firstly confirmed at abandoned paddy terrace (APT) wetland in Ansan. Water sampling for analyzing of physicochemical conditions including nutrients such as NP, $Ca^{2+}$ and $Mg^{2+}$ was performed and the vegetation map for distribution of Sphagnum sp., topographical map, and flora list for companion species were made at field in June 2011. From the results, the Sphagnum sp. in the study site was identified as S. palustre and it covered about 8% of the wetland cover of 3,200 $m^2$. Most distributions of S. palustre were observed at tussock structures as micro-topography by sedges and grasses within a wetland (74%) and the shaded slope area under Pinus densiflora's canopy in wetland boundary (26%). Despite that APT in Ansan is relatively lower wetland in altitude than high moors, the contents of calcium ($0.45{\pm}0.2$) and magnesium ($1.48{\pm}0.6$) ion which are critical limiting factors for Sphagnum spp. were very low levels as well as NP ($PO_4$-P, $0.02{\pm}0.0$; $NO_3$-N, $0.25{\pm}0.3$; $NH_4$-N, $0.06{\pm}0.1$) and it could enable the inhabitation of S. palustre in lower APT.

• Korean Journal of Environmental Agriculture
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• v.40 no.4
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• pp.313-321
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• 2021

BACKGROUND: Ammonia is a causative substance for the fine particulate matters (PM_2.5) and generates dust through atmospheric reactions. Agricultural sector accounts for 79.3% of ammonia emissions in Korea. Urea and composted organic fertilizer (COF) are used in the soil for the purpose of supplying nutrients in grapevine orchards. This study was conducted to investigate estimates of ammonia emission and examine fruit quality from the rain proof cultivation of the 'Beni Balad', applied by urea and COF to the soil. METHODS AND RESULTS: Urea, COF1, and COF2 were applied at the rates of 119, 135, and 271 kg ha^-1 respectively. Ammonia emissionwas measured using a dynamic flow-through method. CONCLUSION(S): Ammonia emissions by urea and COF treatments to 'Beni Balad' soils under rain proof cultivation were calculated to be 2.63, 12.95, 2.05, and 3.97 kg NH₃-N ha^-1 day^-1, respectively for the control, urea, COF1, and COF2. Urea soil application increased soluble solids, firmness, and anthocyanin content in fruits at harvest, and COF1 application increased the soluble solids and anthocyanin content. For all the treatments, acidity increased in the harvested fruits.

• The Korean Journal of Mycology
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• v.52 no.1
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• pp.1-11
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• 2024

The present study aimed to screen unrecorded wild yeasts from Jeju lsland and Jangsado on the southern coast of Korea, and to investigate their microbiological characteristics. To date, Coniozyma leucospermi JJD37-2, Hanseniaspora thailandica JJD44-1, Kluyveromyces nonfermentans JJD15-1, Kockovaella fuzhouensis JJD47-3, Vishniacozyma heimaeyensis JJD8-4, Candida carpophila JSDH24-1, Wickerhamomyces strasburgensis JSDH34-2, Candida savonica HJD6-4, and Candida karawaiewii YP23-3 have not been previously recorded in Korea. In the present study, we investigated the microbiological characteristics of these previously unrecorded yeasts. Except for W. strasburgensis JSDH34-2 strain, none of the strains formed spores, and only the C. leucospermi JJD37-2 strain formed pseudomycelia. Almost all strains grew well in yeast extract-peptone-dextrose (YPD) medium, potato dextrose (PD) medium and yeast extract-malt extract (YM) media. C. carpophila JSDH24-1 and W. strasburgensis JSDH34-2 also grew well in YPD medium containing 10% NaCl. H. thailandica JJD44-1 is fermented to produce glucose, fructose and mannose.

• Korean Journal of Environmental Agriculture
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• v.18 no.1
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• pp.35-40
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• 1999

$N(^{15}N)$ and $P(^{32}P)$ absorption by 2 year-old Cymbidium Jungfrau in solution culture were investigated. Growth, photosynthesis rate, chlorophyll content and mineral composition of Cymbidium in the solution culture with bark or granular rockwool were compared with these parameters in the conventional pot culture. Nitrogen absorption by Cymbidium was higher in full sunlight than in 60% of sunlight while P absorption was higher in 60% of sunlight. Sixty seven % of N absorbed in plant was redistributed to the bulb(39%) and leaves(28%) while 46% of P absorbed was fund in the bulb (36.2%) and leaves (10.2%). Accumulation of P in leaves was 3-fold lower than that of N. N and P absorption in 0.5 or 1 year- old daughter plant Bowing vigorously were greater than in immature daughter or mother plant. The absorption rate of phosphorus in Cymbidium was 350-fold lower than that of barley. Greater shoot length and bulb diameter, and higher fresh weight, photosynthesis rate and chloroployll content were observed in the solution culture than in the conventional pot culture. Solution culture had-also more content of N, P, K and Mg in leaves, bulb and root than conventional pot culture but did not that of Ca. A large part of the nutrient absorption was occurred during vegetative growth. Also, There was no difference between bark and rockwool in the solution culture due to the improvement of poor dispersion of nutrient solution in bark.

• Korean journal of applied entomology
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• v.48 no.1
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• pp.67-72
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• 2009

The kairomonal activity of the aggregation pheromones of Riptortus clavatus for the egg parasitoid, Gryon japonicum, were investigated in soybean field. The parasitism rate of G. japonicum gradually decreased when the distances between pheromone traps and egg sites were increased from 0 to 15 m. The active distance of pheromone source for parasitoid attraction was estimated to be ca. 15 m. Under field conditions, the parasitoid wasp population peaked during the late August and early September, and the parasitism rate increased when the number of pheromone traps was increased from one to three per $165\;m^2$. However, insecticide-treated plots, the level of parasitism recorded is relatively low. Sex ratios in field populations of G. japonicum were female-biased.

• Journal of the Korean Society of Food Culture
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• v.4 no.1
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• pp.103-108
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• 1989

Effects of different processes or texture of cucumber pickles fermented in 7% NaCl solution were studied. Cucumbers were treated with different processes: control; preheating in 7% NaCl, 0.04M $CaCl_2$ solution ($60^{\circ}C$, 1hr); combination of preheating and post microwave heating (5 min, midium high level, 2450 Mhz); preheating in the solution which was adjusted to pH 8.5. In each process the pH and total acidity of brine solution, total pectin contents in alcohol insoluble solids (AIS), hot water soluble pectin (HWSP) contents and firmness of cucumber pickles were determined at 0, 5, 10, 15 and 25 days of storage periods. Total pectin contents and the firmness of pickles were decreased during 25 days of storage. Control group showed the lowest value and post microwave heating group marked the highest value in total pectin contents and firmness retention of cucumber pickles. The results of this study indicated that total pectin content seems to correlate with the firmness of cucumber pickles. However, HWSP content did not show any correlation with firmness of cucumber pickles. Post microwave heating method could be used to retain firmness of fermented cucumber pickles.

• Korean journal of food and cookery science
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• v.4 no.2
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• pp.31-38
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• 1988

The chicken cooked by three different methods were put and sensory evaluation, mechanical and chemical composition test. The results were as following : 1. Standard recipe were as followig : \circled1 Kettle cooking was chicken 700 g, waxyrice 100 g, garlic 30 g, water 2000 cc, time 60 min. \circled3 Pressure cooking was chicken 700 g, waxyrice 100 g, garlic 30 g, water 2000 cc, time 30 min. \circled3 Microwave cooking was chicken 700g, waxyrice 100 g, garlic 30 g, water 1000 cc, time 30 min. 2. Sensory evaluation \circled1 There were no typical difference of the color of soupstock with in the three cooking methods. \circled2 The turbidity of soupstock was from Kettle cooking, microwave cooking and pressure cooking in turn. \circled3 There were no typical difference of the viscosity of soupstock with in the three cooking methods. \circled4 The kettle cooking was the best of mouthfeel and taste. \circled5 There were no typical difference of muscle, with in the three cooking methods. 3. Mechanical Test \circled1 The result of the cutting force of muscle which measured by rheomether were the leg muscle was more tough than breast muscle. \circled2 The viscosity of boiled rice was from kettle cooking, pressure cjooking and microwave cooking in turn. \circled3 The result of the turbidity of soupstock which measured by spectrophotmeter was from kettle cooking, pressure cooking and microwave cooking in turn. 4. Proximate chemical composition \circled1 Protein of muscle was 20.30-25.67%, Soupstock was 0.29-0.72% \circled2 Fat of muscle was 27.29-47.15% , Soupstock was 37-68.38%. \circled3 Potasium of muscle was 2.75-3.6 mg, Soupstock was 1.15-6.3 mg. \circled4 Iron of muscle was 1.17-1.39 mg, Soupstock was 0.96 mg.

• The Korean Journal of Ecology
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• v.27 no.3
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• pp.165-171
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• 2004

Weight loss and nutrients dynamics during decomposition of oak roots (diameter classes: R₁〈0.2㎝, 0.5㎝〈R₂〈1㎝, 1㎝〈R₃〈2㎝, 2㎝.〈R₄〈4㎝) (Quercus acutissima) were studied for 33-months in Kongiu, Korea. After 33-months, decomposition rate of R₁, R₂, R₃ and R₄ was 49.6%, 47.5%, 66.4% and 66.1%, respectively. The decomposition constant(k) for R₁, R₂, R₃, and R₄ was 0.249/yr, 0.234/yr, 0.397/yr and 0.393/yr, respectively. Larger diameter class of the root lost more weight than smaller diameter class. N concentration in decomposing oak roots increased in all diameter classes. After 33-months, remaining N in R₁, R₂, R₃ and R₄ was 66.5%, 80.7%, 84.4% and 44.4%, respectively. K concentration in decomposing oak roots decreased in early part of decomposition and then increased in later stage of decomposition. After 33-months, remaining P in R₁, R₂, R₃ and R₄ was 64.7%, 62.4%, 93.1% and 30.7%, respectively. K concentration in decomposing oak roots decreased rapidly in early stage of decomposition. Remaining K in R₁, R₂, R₃ and R₄ was 11.6%, 10.6%, 5.9% and 7.7%, respectively. Ca concentration in decomposing oak roots showed different among diameter classes. After 33-months, remaining Ca in R₁, R₂, R₃ and R₄ was 66.2%, 51.0%, 39.1% and 48.3%, respectively. Initial concentration of Mg in oak root was higher in smaller diameter class. After 33-months, remaining Mg in R₁, R₂, R₃ and R₄ was 15.3%, 29.9%, 24.5% and 69.4%, respectively.

• Korean Journal of Environmental Agriculture
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• v.13 no.1
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• pp.1-9
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• 1994

To investigate differences in Cu contents in paddy soils and rices, being affected by air pollutants from the Janghang Smelter, soil samples at the different directions and surface (0-15cm) and subsurface (15-30cm) were collected in 1982 and 1990, and rice plants at the soil corresponding sampling sites in 1990 were also at separately collected from the Janghang Smelter area. Soil samples were extracted with $4M-HNO_3$ and plant samples were digested with a mixture of $HNO_3$ and $HClO_4$ for analyzing Cu, Zn, Cd and Pb by atomic absorption spectrophotometry. The Cu contents in soils ranged from 5.1 to 391.0 mg $kg^{-1}$. The average content of Cu in 1990 was higher than that in 1982. The Cu content in soils nearer to the center of the smelter was higher than that farther from the center. The Cu content was highest at the east direction, and was in order of east > north-north east = north east > north. The variation of Cu levels in soil at east sites was more considerable than other directions. The Cu level in surface soils was higher than that in subsurface soils. The Cu contaminated area was within 5 km at east, and 3 km at north-north east and north east. A significant correlation was found between Cu content in surface soils of 1982 and that in surface and subsurface soils of 1990, and between Cu content in soils and soil properties such as organic matter(OM), available phosphate, available silicate, exchangeable $Ca^{++}$ and $Na^+$ in 1982. The Cu content in brown rice ranged from 0.4 to 3.6 mg $kg^{-1}$, and was the lowest in parts of rice plant, and Cu content in a part of plant was 13.75 times higher than that in brown rice. The Cu content of leaf sheath, stem and brown rice was correlated with the levels of Cd, Zn, Cu and Pb in soils. The Cu content in soil regardless of years and soil depths was correlated with Zn and Pb in soil in the area affected by waste gas.

• Applied Biological Chemistry
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• v.15 no.1
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• pp.19-25
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• 1972

A kind of peptide which posseses an yeaststatic activity was isolated from Astragalus membranaceus Bunge and following characteristics was obtained. 1. The isoelectric pH of this peptide was 8.2 and histidine, an alkaline amino acid, was identified from this peptide. 2. This substance showes conspicuous heat stability and does not indicate any remarkable reduction of yeaststatic activity even for 5 hours treatment at $100^{\circ}C$. or for 30 minutes at $121^{\circ}C$. 3. The inhibitory activity of the yeast growth is not originated from the yeastcidal action but yeaststatic effect of this sample. 4. The sample shows strong stability ranging from pH 2 to 10. 5. The saccharide; glucose, sucrose, maltose, gives no effect on the yeaststatic activity of the sample even high concentration, 15 percent, and also no effect gives by magnesium, calcium and phosphate salts. 6. The available concentration of this sample on the inhibition of yeast growth was located at the ppm extent, for example, the concentration of fifty percent growth inhibition to Saccharomyces cerevisiae or S. carsbergensis was 4 ppm and 3 ppm to Candida pulcherrima, 13 ppm to S. coreanus, 18 ppm to S. sake and 38 ppm to C. tropicalis. 7. On the alcohol fermentation of S. coreanus, the peptide, an yeast growth inhibitor, gives no effect at all. 8. This substance is named as Astradix-P (Astragalus membranaceus, Radix, Peptide).