• Korean Journal of Soil Science and Fertilizer
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• v.17 no.2
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• pp.125-133
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• 1984

To obtain the basic date for the improvement of cultural and managemental problems caused by soil characteristics and soil productivity in rice cultivation of Honam area, morphological characteristics of rice soils were investigated in Mangeng-Dongjin and Yeongsan Water-sheds, and compaired differences between two major Watersheds. The results obtained are summarized as follows: 1. According to U.S.D.A. Soil Taxonomy Classification System, eight great groups are distributed in rice soils of two major Watersheds. More than 50% of rice paddy soils are classified as Haplaquepts. 2. Two Watersheds are quite different in soil parent materials. In Mangeong-Dongjin Watershed, most soils (55.1%) are derived from fluvic-marine deposits. Remainders are derived from local alluvium (24.7%) and alluvium (14.2%). But in Yeongsan Watershed, the order is local alluvium>alluvium>fluvio-marine deposits. 3. Rice soils occur mostly in coastal and inland flat-site with the slope of less than 2% (57.8%) in Mangeong-Dongjin Watersheds. However, in Yeongsan Watershed, flat-site and low undulating terrace are mostly distributed (52.9%). 4. About 81.9, 61.4 and 53.3% of rice soils are classified as fine textured in Yeongsan, Dongjin, and Mangeong Watersheds, respectively. 5. More normal paddy soils and less sandy paddy soils are distributed in Yeongsan Watershed. The results indicate that more rice soils are classified as productivity classes of I and II in Yeongsan Watershed than in Mangeong-Dongjin Watersheds.

• Journal of Life Science
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• v.23 no.2
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• pp.167-174
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• 2013

Peroxiredoxin 6 (Prx 6) is a member of the thiol-specific antioxidant protein family, which may play a role in protection against oxidative stress and in regulating phospholipid turnover. The aim of this study was to determine whether a human Prx 6/Luc vector was stably expressed and responded to antioxidants in a lung cell line (NCI-H460). To achieve this, the luciferase signal, hPrx 6 mRNA expression, and superoxide dismutase (SOD) activity were measured in transfectants with a hPrx 6/Luc plasmid after treatment with four antioxidant extracts, including Korea white ginseng (KWG), Korea red ginseng (KRG), Liriope platyphylla (LP), and red Liriope platyphylla (RLP). First, the hPrx 6/Luc plasmid was successfully constructed with DNA fragments of human Prx 6 promoter, amplified by PCR using genomic DNA isolated from NCI-H460 cells, and cloned into the pTransLucent reporter vector. The orientation and sequencing of the hPrx 6/Luc plasmid were identified with restriction enzyme and automatic sequencing. A luciferase assay revealed significant enhancement of luciferase activity in the four treatment groups compared with a vehicle-treated group, although the ratio of the increase was different within each group. The KRG- and LP-treated groups showed higher activity than the KWG- and RLP-treated groups. Furthermore, the luciferase activity against RLP occurred roughly in a dose-dependent manner. However, the level of endogenous hPrx 6 mRNA did not change in any group treated with the four extracts. The SOD activity was in agreement with the luciferase activity. Therefore, these results indicate that the hPrx 6/Luc vector system may successfully express and respond to antioxidant compounds in NCI-H460 cells. The data also suggest that the Prx 6/Luc vector system may be effectively applied in screening the response of hPrx 6 to antioxidant compounds in transgenic mice.

• Journal of The Korean Society of Grassland and Forage Science
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• v.23 no.4
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• pp.247-254
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• 2003

A study was carried to compare two varieties of tall fescue(Festuca arundinacea Schr.): Fawn (endophyte infection) and Roa(endophyte-free). The study examined plant height, botanical composition, and dry matter yield of mixed pasture. The cattle grazed on a mixed pasture of tall fescue species and orchardgrass(Dactylis glomerata L.), perennial ryegrass(Lolium perenne L.) and white clover(Trifolium repens L.) during March 22, 1997, to September 21, 1997. The number of grazing animals was 4.3/ paddock(50m x50m) and was adjusted according to the condition of pasture. Dry matter yields determined on ungrazed pasture(7-time harvests) were 1,690 $\pm$407kg and 1,128 $\pm$ 238kg/ha on pastures consisting of Fawn and Roa, respectively. This difference was significant(P<0.01). There were 17.71 $\pm$ 1.27cm and 12.83$\pm$0.90cm in average plant lengths of Fawn and Roa(P<0.01), respectively The botanical composition of tall fescue and orchardgrass in the mixture treatment included in the Fawn variety were shown in 34.2 and 3.8％, comparing Roa with 17.1 and 9.6％, on the 21th of September, 1997, respectively. Tall fescue Roa represented a higher botanical composition than orchardgrass(a main species on Cheju). Crude protein content of Fawn was slightly less than that of Roa. From these results, we may conclude that Roa variety is nutritionally better, but is less adaptible to high temperature climate than Fawn. However, Roa variety is still better than orchardgrass in high temperature conditions.

• Journal of agriculture & life science
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• v.46 no.4
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• pp.141-153
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• 2012

Samples collected from six tomato farms(A, B, C : soil culture, D, E, F : Nutriculture) located in Gyeongsangnam-do were tested for the analyses of biological(sanitary indications, major foodborne pathogens, fungi), chemical(heavy metals, pesticides) and physical hazards. The highest levels of total bacteria(7.5 log CFU/g) and coliforms(5.0 log CFU/g) in soil culture farms were higher than those of nutriculture farms(total bacteria: 2.5 log CFU/mL, coliforms: 0.6 log CFU/mL). In crops and personal hygiene soil culture farms showed a slightly higher contamination levels. From all farms, the levels of fungi in soil farms were higher than those of nutrient solution. In case of major pathogens, Bacillus cereus and Staphylococcus aureus were detected in all sample with the exception of nutrient solution. Meantime, Escherichia coli, Listeria monocytogenes, E.coli O157 and Salmonella spp. were not detected. For airborne bacteria, soilculture farms showed less contamination than nutriculture farms. A piece of glass and can was confirmed asphysical hazards. Heavy metal(Cd, Pb, Cu, Cr, Hg, Zn, Ni and As) and pesticide residues as chemical hazards were detected, but their levels were lower than the regulation limit. These results demonstrate that potential hazards on harvesting stage of tomato fam were exposed. Therefore, proper management is needed to prevent biological hazards due to cross-contamination, while physical and chemical hazards were in appropriate levels based on GAP criteria.

• Journal of Food Hygiene and Safety
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• v.36 no.5
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• pp.447-453
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• 2021

In this study, the effectiveness of physical control technology, a combined light sterilization (LED, UV) and hot water treatment in reducing Aspergillus ochraceus for food production environment was investigated. In brief, 1 mL aliquot of A. ochraceus spore suspension (10^7-8 spore/mL) was inoculated onto stainless steel chips, which was then dried at 37℃, and each was subjected to different physical treatment. Treatments were performed for 0.5, 1, 2, 5, 8, and 11 hours to reduce the strains using a light-emitting diode, but no significant difference was confirmed among the treatments. However, a significant reduction was observed on the chips treated with UV-C exposure and hot water immersion. After being treated solely with 360 kJ/m² of UV-C on stainless steel chip, the fungi were significantly reduced to 1.27 log CFU/cm². Concerning the hot water treatment, the initial inoculum amount of 6.49 log CFU/cm² was entirely killed by immersion in 83℃ water for 5 minutes. Maintaining a high temperature for 5 minutes at the site is difficult. Thus, considering economic feasibility and usability, we attempted to confirm the appropriate A. ochraceus reduction conditions by combining a relatively low temperature of 60℃ and UV rays. With the combined treatments, even in lukewarm water, A. ochraceus decreased significantly through the increases in the immersion time and the amount of UV-C irradiation, and the yield was below the detection limit. Based on these results, if work tools are immersed in 60℃ lukewarm water for 3 minutes and then placed in a UV sterilization device for more than 10 minutes, the possibility of A. ochraceus cross-contamination during work is expected to be reduced.

• Korean Journal of Ichthyology
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• v.32 no.4
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• pp.210-221
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• 2020

Since the introduction of Israeli carp into Korea for farming in 1973, there are no breeding studies on developing Korea Israeli carp (domestic) so far. This study performed gene-based cross-breeding studies to restore genetic diversity of lowered Israeli carp through continuous inbreeding, and for rapid growth and better scales. This study produced four cross-breeding groups (F1) using Koean Israeli carp and Chinese Songpu mirror carp for the improvement of growth and scale of Israeli carp in Korea. And mating scheme for breeding groups was set in consideration of the morphological analysis and genetic distance of broodstock. In addition, this study used microsatellite markers and genotype data to analyze genetic diversity and parentage analysis. As a result, the average N_A and H_E values of Korean select broodstock are 8.3 and 0.743, and F1 is 13.0 and 0.764. This study shows that the genetic diversity of F1 has been recovered over Korean Israeli carp through breeding between Korean Israeli carp and Chinese Songpu mirror carp. Common Israeli carp in Korea reached 1.7 kg in 17 months, and improved Israeli carp reached to 2.2 kg. The KC (Korea×China, KC) group was 2.52 and broodstock group was 3.15. F1 showed lower scale score (0.63) than broodstock. The improved carp (F1; CK, KC) had 20% better scales than the parent group (F0), which improved 27% in weight and 25% in scales compared to common Israeli carp. The Israeli carp developed by the genetics-based breeding grew quicker and had improved genetic diversity and fewer scales, which will be of great value for Korean Israeli aquaculture industry due to good marketability.

• Korean Journal of Heritage: History & Science
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• v.40
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• pp.73-104
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• 2007

Centering around ruins recognized of being relatively early stage related to flat tile and brick, excavated in Silla capital area, the study attempted elementary approach to seek the appearance time of every remain through comparing them from the excavated cases and production methods of Short beating, Medium beating plate, Long beating plate and Stamped-roof tile. Gyeongju began to use the short beating plate made of tile-less plates or tile plate and increased its quantity. That is deemed to be due to efficiency of beating plate making methods, and moreover to be limited only for use in the palace castle and offices. That is, making short beating plates is presumed to be made merely under some definite objectives. Medium beating plate has been spread to the whole country since Silla and Baekje united. Differently from Koguryo and Baekje, Silla had its unique Beating-plates making technology available for mass-production, which was spread to the whole country and resulted in disappearing of Koguryo and Baekje technology. Long beating plate was not nearly founded in Gyeongju area, but flat tile and common tile excavated in Sachunwang Temple site and Samrang Temple 3rd remains are known. In the outskirts of Gyeongju, long beating plate appeared between the latter half of 8C and the beginning of 9C. Until now, different views have raised to appearance of long beating plate of Unified Silla, which is expected to be clarified under the situation excavated by position relations. Stamped-roof title in Gyeongju is estimated as used after the datum point year 679. While in Baekje area, five stems and branches were involved, in Silla area, code or sign was shown much. The difference between two areas would be due to each other factory, and especially the marked contents werenot letters, which means it had been changed from Baekje s existing-methods. That is, it says the production environment changed owing to Silla's merging. And stamped-roof tile was temporarily used in Gyeongju but soon disappeared, which was because Silla beating plates made under cylinder-shaped tile barrel(圓筒瓦桶) and hitting-pressing of Medium beating plate had beenspread to the whole country, so the production technology of Koguryo and Baekje was naturally dismissed. In consequence, the mergence by Silla brought about unification of each nation's special technology.

• The Korean Journal of Mycology
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• v.49 no.1
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• pp.87-100
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• 2021

This study aimed to isolate wild yeasts obtained from flowers and soil of the Wolpyung park, Daejeon city and Gykpo beach, Buan, Jeollabuk-do in Korea, and to further characterize previously unrecorded wild yeast strains. In total, 88 strains of 62 different species of wild yeasts were isolated from 75 samples obtained from the Wolpyung park. Among these, six strains of Trichosporon moniliiforme and four strains each of Papiliotrema flavescens and Candida melibiosica were isolated. Additionally, 39 strains of 30 different species of wild yeasts were isolated from 35 samples collected from the Gykpo beach. Among the 127 isolated wild yeast strains, 10 strains, including Apiotrichum porosum ASCM32-1, were previously unrecorded. All the 10 previously unrecorded yeasts were oval or global in shape, and three strains, including Candida athensensis WP4-90-3, formed spores. Three strains, including Vishniacozyma taibaiensis WP13-2, were halophilic yeasts which grew in 15% NaCl-containing YPD(yeast extract-peptone-dextrose) medium. Five strains, including C. athensensis WP4-90-3, showed 15% ethanol resistance. Cell-free extracts from Candida oleophila WP5-19-1 and Wickerhamomyces anomalus HO9-2 showed the highest β-glucuronidase inhibitory activity (49.0%) and neutrophil elastase inhibitory activity (38.4%), respectively.

• Journal of Mushroom
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• v.18 no.4
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• pp.331-338
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• 2020

This study was conducted to cultivate new Lepista nuda varieties with shorter cultivation period and better fruiting body compared to that of wild strains, for mass production and commercial application. Eighteen genetic resources of L. nuda were collected and grown in boxes using rice straw-fermented growth medium. Four lines with fruiting bodies were formed and selected as cross-breeding lines. Although 657 combinations were crossed through monospore crossing, only 17 combinations were bred between the 'CBMLN-19' line and the 'CBMLN-30' line. Among them, 8 lines with fast mycelial growth and high density were selected. After inoculating the rice straw-fermented growth medium with 14 genetic resources and 8 cross-breeding lines, their incubation period was investigated. Six of the cross-breeding lines completed their incubation in 20 days, while 7 of the 14 genetic resources took more than 40 days to complete their incubation, reducing the incubation period by more than 20 days in most cross-breeding lines. After the incubations were completed, the clay loam soil was covered with for post-cultivation, and when the mycelial cultivation was complete, the formation of fruiting bodies was induced after scraping the mycelial bodies under these environmental conditions: 14℃, 95% relative humidity or higher, and 1,500 to 2,000 ppm CO2 concentration. The temperature was reduced to 6℃ at night, resulting in a low temperature shock. Thus, 4 lines of fruiting bodies occurred from two genetic resources 'CBMLN-31' and 'CBMLN-44' and two cross-bred lines 'CBMLN-96' and 'CBMLN-103'. After inoculation, the longest period for fruiting bodies to occur was 100 days for the control:, the genetic resource 'CBMLN-31', and the shortest period (45 days) was observed for the cross-breeding line 'CBMLN-103'. The result of the investigation of the fruiting body characteristics shows that the cross-bred line 'CBMLN-103' showed a small form with 1.9 g of individual weight and 123validstipes per box, which was the highest incidence among the four lines. Another cross-bred line, 'CBMLN-96', had an individual weight of 5.5 g, which is larger than that of 'CBMLN-103'; however, the number of valid stipes per box was 30 less than that of 'CBMLN-103'. Quantity analysis showed that the control, 'CBMLN-31', had the highest quantity of 783 g per box, followed by the cross-bred line, 'CBMLN-96' with 165 g per box, and then the 'CBMLN-103' with 232 g. The quantity of the two crossbred lines was lower than that of the control 'CBMLN-31'; however, the amount of fruiting bodies was higher, and the cultivation period was shortened by 32 to 33 days. Therefore, these two lines would be selected as superior lines.

• Journal of Food Hygiene and Safety
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• v.37 no.6
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• pp.400-410
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• 2022

This study was performed to analyze the microbial contamination levels of three non-heated rice cake manufacturers in terms of seasonal manufacturing process and to investigate the effects of summertime soaking on contamination levels and temperature-controlled soaking in water on reduction in microbial levels. The total aerobic bacteria (TAB) ranged from 2.69 log CFU/g to 5.08 log CFU/g in the produce, but the microbial contamination increased sharply during soaking. The levels of TAB and coliforms during summer soaking were 7.01 and 3.96 log CFU/g, respectively, and this was significantly higher than those in other seasons. The contamination level was high in the subsequent freezing, with the TAB level (6.24 log CFU/g) exceeding the legal standard. The temperature of soaking water in summer increased from 19.1℃ to 26.8℃ after 12 h of soaking. The microbial contamination was significantly high commensurate with increased soaking time, and the TAB level in the frozen process exceeded the legal standard from 9 h of soaking. The use of ice packs to prevent the increase in temperature of the soaking water in summer resulted in maintenance of temperature at 20.1℃ for up to 12 h. The average TAB value in the freezing process was 4.42 log CFU/g after 12 h of soaking, and this is 1.77 log CFU/g lower than that before. Based on these results, it was determined that controlling the soaking time and water temperature are essential for the production of a safe unheated frozen rice cake. The safety of the HACCP system could be established by applying these preventive management standards.