• Korean journal of applied entomology
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• v.19 no.4 s.45
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• pp.212-220
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• 1980

The purpose of this study is to establish a standard amount of pesticide per unit area of the lumber over the sea level. This establishment is required in applying the sea water dipping disinfection method to the imported soft woods to control the pests living on the surface of the lumber. The major findings of this study are as follows; 1. The average length and diameter of the imported soft wood was respectively 11.12m and 76.46Cm. 2. The average cubic content of the lumber over the sea level to the whole cubic content was 20.82 percent. 3. The ratio of the lumber over the sea level to the whole cubic content was 2.3356 at the $95\%$ significance level. 4. The sampling error of the ratio of the area of the lumber over the sea level to the cubic content was lower in the case of the pieces of lumber in a vessel than the average between ten tressels. 5. The optimum amount of pesticide spray per $1\;M^2$ of the soft wood was 0.298 cc in the case of using the hand spray, but 0.245 cc the motor spray. 6. For example, in the case of applying the sea water dipping disinfection method to the 5,000 $M^3$ of the imported soft wood, the required amount of pesticide with a motor spray can be estimated as follow. $$5,000\;M^3\times2.333=11,678\;M^2$$ $$11,678M^2\times0.295=3,445cc$$.

• Journal of Life Science
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• v.29 no.12
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• pp.1378-1385
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• 2019

The nutritional composition and optimal eating stage of the super mealworm, Zophobas atratus (Coleoptera : Tenebrionidae), were investigated to explore its use as a food ingredient. It was determined that 10^th instar larvae were most suitable for eating in terms of nutritional value as well as economic aspects. To improve the quality of powder production, the nutritional value of 10^th instar larvae before and after degreasing was analyzed. After drying the larvae powder, crude protein was the most abundant nutrient both before (52.3%) and after (60.6%) degreasing while crude fat measured 36.3% and 21.7% before and after degreasing, respectively. In terms of essential amino acids, leucine levels were highest and 1.3 times greater after degreasing (4.5%) than before (3.5%). Oleic acid, the highest unsaturated fatty acid in larvae, was 31.7% after degreasing which was 1.1 times higher than before (33.2%). Among various major minerals, potassium was most abundant and 1.4 times higher after degreasing (1267.0 mg/100 g) than before (879.3 mg/100 g). Harmful substances were 1.3 to 2.0 times lower in the degreased larvae, although mercury or pathogenic bacteria were not detected in either group. We therefore conclude that degreased Z. atratus larvae are more suitable for eating than before degreasing.

• Journal of Sericultural and Entomological Science
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• v.29 no.2
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• pp.73-81
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• 1987

This investigation was carried cut to obtain the reeling water conditions in Korea. The analyzed items of water were pH, colority, turbidity, acidity, alkalinity, solids electric conductibity hardness and heavy metal ions. About 40% of the reeling water were found to be agreeable, 30% were acceptable provided with some quality control and the others were out of acceptable range mainly based on the M-alkalinity, acidity, pH and total hardness. It was found that there was a following relationship between total hardness and electric conductibity with the relative correlation coefficient r=0.9145. y=15.967+0.22774x Where x, y are electric conductivity and total hardness respectively.

• Journal of Korean Society of Archives and Records Management
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• v.1 no.1
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• pp.231-243
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• 2001

The sterilization method of records by fumigation using mixed gas of methyl bromide(MB) and ethylene oxide(ETO) has been generally used as a way to protect biological deterioration by microorganisms and insects. In this study, we confirmed sterilization effect of MB and ETO [86 : 14(Vol.%)] on and analyzed toxicity on microorganisms isolated from records. To analyze sterilization effect of fumigation on microorganisms and insect, we have fumigated microorganisms and insect with a various amounts mixed gas of MB and ETO, and various exposure time. Insect was sterilized at all experimental conditions. In microorganisms, sterilization effect was detected only when the mixed gas was treated at $120g/m^3$ concentration for at least 24 hrs. To test the possibility of isolated microorganisms as a threat to human health, it was investigated that toxicity test using yeast, radish and cancer cells on microorganisms. Only Aspergillus oryzae had an inhibition effect on growth of yeast. radish and cancer cells, respectively. These results demonstrate that sterilization effect can occur at low concentrations of the mixed gas on insect but requires higher concentrations of the mixed gas on microorganisms. In addition to, it is suspected that the possibility of the microorganism as a threat to human health is little.

• Korean Journal of Environmental Agriculture
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• v.36 no.4
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• pp.241-248
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• 2017

BACKGROUND: RNA interference (RNAi) eliminates or decreases gene expression by disrupting the target mRNA or by interfering with translation. Recently, RNAi technique was applied to generate new crop traits which provide protection against pests. To establish the environmental risk assessment protocol of RNAi LMO in lab scale, we developed dsRNA expression system using E. coli and tested acute oral toxicity assay to honey. METHOD AND RESULTS: The dsRNA expression vector, L4440, was chosen and cloned 240 bp of Snf7 and GFP gene fragment. To develop the maximum dsRNA induction condition in E. coli, we tested induction time, temperature and IPTG concentration in media. To estimate the risk assessment of dsRNA to honey bee, it has been selected and cultured with dsRNA supplement for 48 hours according to OECD guideline. As a result, the optimum condition of dsRNA induction was $37^{\circ}C$, 4 hours and 0.4 mM IPTG concentration and the difference between Snf7 and GFP dsRNA molecules from E. coli was not significant in survival and behavior to honey bee. Furthermore, blast search results indicated that effective match of predicted dsRNA fragments were not existed in honey bee genome. CONCLUSION: In this study, we developed and tested the acute oral toxicity of dsRNA using E. coli expression system to honey bee.

• Journal of Sericultural and Entomological Science
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• v.50 no.2
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• pp.76-81
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• 2012

Silk protein has been explored to be used for biomedical applications for several decades. However, it has not been used in this field cause to their irreversible crystallization after dissolving in water. The existing methods of silk protein hydrolysis using silkworm cocoon were used with harmful solvents and through a very complicated process. Therefore, we have developed novel methods for the production of water-soluble hydrolysate using silkworm gland. We manufactured two types of silkworm gland-derived hydrolysate (water-soluble SGH, SSGH; total SGH, TSGH) and compared the characteristics with commercial cocoon-derived sericin hydrolysate (CSH). The molecular weight of SGH ranged from 7 to 50 kDa (SSGH) and 5 to 15 kDa (TSGH) within glycine, alanine, and aspartic acid as a main amino acid composition. In contrast, CSH ranged from 15 to 50 kDa within serine and aspartic acid. The results of FTIR implied that SGH was more soluble form than CSH, as shown by the decrease in the ${\beta}$-sheet structure at $1630cm^{-1}$ on amide I peak. In comparison with 10% fetal bovine serum, 0.1% (1 mg/ml) SSGH had equivalent effect on the proliferation of human dermal fibroblasts and mesenchymal stem cells. All results of the SSGH made by novel manufacturing process indicate the SSGH is more preferable as a culture medium supplement than cocoon-derived sericin.

• The Korean Journal of Mycology
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• v.5 no.1
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• pp.7-12
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• 1977

For this study 3 samples of the home-made meju and 3 samples of the improved meju were selected according to their characteristics. A total of 25 strains of true fungi were isolated from the samples of the home-made meju and identified by the Key of Alexopoulos and Raper, using a strain Aspergillus oryzae A-113 as a control. Amylolytic and proteolytic enzyme activities of the isolated strains were investigated ana the results obtained were as follows. 1. The 25 strains from the home-made meju were identified into 2 Aspergillus oryzae, 14 Asp. flavus, 6 Penicillum spp. 1 Candida sp 1 Spicaria sp and 1 Rhizopus sp. 2. The 3 strains from the improved meju were all identified as Aspergillus oryzae. 3. Aspergillus flavus, A-B, from the home-made meju was found to he the strongest strain in ${\alpha}-amylase$ activity and also to be similar to the strains of Aspergillus orzae from improved meju. 4. Aspergillus flavus, A-7, from the home-made meju was found to be the strogest strain in ${\beta}-amylase$ activity and stronger than that from the improved meju. 5. Aspergillus flavus B-3, was found to be the strongest strain in protease activity and stronger than that from the improved meju. 6. Some of the strains from the home-made meju turned out to be harmful strains, such as Penicillium spp. which secrete antibiotics, Asp. flavus which secretes mycotoxin, Candida sp which causes skin diseases, Spicaria sp. which is a insect pathogen. 7. Rhizopus sp was also found but it has not been proved to be harmful.

• Korean Journal of Heritage: History & Science
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• v.54 no.2
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• pp.194-215
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• 2021

Termites are important decomposers in the ecosystem. They are also economically significant structural pests. In this study, we reviewed the developments of termite control and recent research on termite management to provide information on the prevention and control of termites. In Korea, most of the damage to wooden historical buildings is caused by subterranean termites. Reticulitermes speratus kyushuensis is the main species, which is widely found throughout the country. In the early 1900s, inorganic insecticides, such as arsenic dust, were used for termite control. After the synthesis of chlorinated hydrocarbon pesticide in the 1940s, it was widely utilized and demonstrated high termite control efficacy. However, chlorinated hydrocarbon insecticides were later banned, disappearing from markets after reports emerged concerning environmental contamination and toxicity to humans. Therefore, the termite control industry sought a new termiticide; hence many pesticides were utilized for termite control. Organophosphate (1960s), carbamate (1970s), pyrethroid, and insect growth inhibitor (1980s) were newly synthesized and adopted. In the 1990s, the first commercial baits using chitin synthesis inhibitors (CSI) were developed, providing a means to eliminate an entire colony of subterranean termites around a structure. Many studies have been carried out on soil termiticides (liquid termiticides) and CSI baits to increase their efficacy, and different baits such as aboveground bait stations, fluid bait, and high-durability bait were also developed in the 2000s. In addition, the paradigm of termite control has shifted from localized treatments using soil termiticides to area-wide pest management using CSI baits to create termite-free zones and protect buildings over time. Termite infestations in wooden historical buildings in Korea have been reported since 1980, and considerable attention was drawn in the 1990s when several UNESCO world heritages such as the Jongmyo Shrine and the Janggyeong Panjeon Depositories of Haeinsa Temple were infested by subterranean termites. Since then, a survey of termite infestation in wooden architectural heritage has been conducted, and the National Research Institute of Cultural Heritage and Heritage Care Program regularly monitors those properties. Finally, we suggest termite management using primarily CSI baits, selective application of various soil treatments applied to the object, foundation soil treatment, research and development of durable termite baits, application of area-wide programs for wooden-building complexes, application of integrated termite management (ITM), and regular education for owners and managers to prevent and reduce termite damage.

• Journal of Soil and Groundwater Environment
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• v.11 no.1
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• pp.54-64
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• 2006

Chromated copper arsenate (CCA), a wood preservative, has been widely used to protect wood products from attacks by bacteria, fungi and insects. However, the use of CCA is currently forbidden or limited to some applications in many countries because the toxic elements (Cr, Cu, and As) of CCA are released into the environments during outdoor uses, which may cause adverse health effects on humans and ecological systems. This study was conducted to investigate the distributions of chromium, copper and arsenic in soils adjacent to two CCA-treated wood structures. In a 7 month old pond entry structure, ten surface soil samples (0-2.5 cm) were collected at lateral distances of 0, 0.5, and 1 m from the stairway, and nine surface soil samples were collected beneath the deck. Nine top soil samples were taken from a 2 year old sound barrier structure at lateral distances of 0, 1, and 2 m. Background surface soil samples were also collected from each structure. Samples were analyzed for some physicochemical properties such as pH, electrical conductivity, organic matter content, and soil texture. Following the extraction of the elements with a microwave digestion system, samples were analyzed for Cr, Cu, and As. The concentrations of the three elements in soils adjacent to the structures were significantly elevated compared to the background levels, indicating that the elements have been leached out of the structures. Released e1ements showed lateral concentration gradients within 1 m. The elevations of the three elements in soils underneath the deck did not seem different (background-corrected concentrations: Cr, 5.01 mg/kg; Cu, 5.50 mg/kg; As, 4.91 mg/kg), while the elements in soils near the sound barrier were elevated in the order of As>Cu>Cr with measured concentrations of 49.7, 44.7 and 52.5 mg/kg, respectively. Background As, Cu, and Cr concentrations near the sound barrier were 9.88, 30.8, and 46.5 mg/kg, respectively. These results showed that CCA constituents are released into the environment and it is suggested that risk assessment need to be conducted to investigate harmful effects of the released elements on humans and ecological systems.

• Korean Journal of Microbiology
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• v.54 no.4
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• pp.410-419
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• 2018

It is urgently required to construct safety data on agricultural by-products imported for use as medium materials for domestic mushroom production. However, research on microorganisms is insufficient. This study was conducted to investigate the presence of bacteria that have the possibility of harmful effects on human, plants and mushroom in wheat straw, peatmoss, cottonseed hull, cottonseed meal, and beet pulp imported from Australia, Canada, China, Egypt, Germany. Bacteria were found in the range of $1.35{\times}10^2$ to $8.34{\times}10^6CFU/g$. As a result of 16S rDNA sequence analysis, total of 19 genera and 45 species of bacteria were identified. Bacillus genus was dominant, followed by Paenibacillus genus. At the species level, diverse species was in the order of Firmicute, Proteobacteria and Actinobacteria. Regarding the agricultural by-products, straw and peat moss had more diverse bacteria than other agricultural by-products. Among the indentified bacteria, 6 species of 5 genera (Enterobacter asburiae, Enterobacter ludwigii, Stenotrophomonas maltophilia, Pseudomonas monteilii, Bacillus anthracis, and Cellulosimicrobium funkei) were present as potent harmful bacteria to human. Surprisingly, both the human and plant pathogenic Klebsiella pneumoniae subsp. pneumonia was present. Bacillus altitudinis was present as a plant pathogen. Lysinibacillus sphaericus, an insect pathogen, and Ochrobactrum pseudogrignonense, a mushroom pathogen, were also present. The results of this study confirmed that several kinds of pathogenic bacteria were present in the agricultural by-products for the mushroom cultivation medium imported into Korea. Our work suggests that hygiene inspection and management is urgently needed for imported agricultural by-products to be safely used for mushroom production.