• Journal of Conservation Science
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• v.27 no.4
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• pp.345-356
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• 2011

To remove metal stains of the ceramics, chemical cleaning is essential case by case. This study investigated the removal characteristics of iron stains by oxalic acid and citric acid including their application methods of soaking and poultice. The soaking method in cleaning agents showed removal process by color difference and released iron contents from iron stains on ceramics. Iron stains were removed successfully from ceramics, which soaked in oxalic acid for 60 hours. However, it is recommendable to soak in 0.25M oxalic acid for one to three hours because most iron stains were disappeared in 3 hours soaking. Citric acid is less effective than oxalic acid in removing iron stains because of heavy molecular weight and low acidity. Poultices (bentonite, sepiolite, activated carbon fiber and celite) with oxalic acid were applied on contaminated ceramics. After ten hours, iron stains on ceramics were removed successfully by poultice. Among them, bentonite and sepiolite have better application. Therefore, sepiolite with 0.25M oxalic acid was applied on the iron stains of whiteware and celadon from Ma Island, and then stains were removed. However, it is judged that the application methods can be varied according to the form and depth of contaminant. In addition, the residues of poultice on the ceramics will be considered for preventing contamination.

• Journal of Food Hygiene and Safety
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• v.27 no.2
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• pp.133-140
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• 2012

Movement and accumulation of cadmium in male Sprague-Dawley rats, fed with brown rice from nearby Janghang smeltery area were investigated. The rat fed with five different cadmium level diets made with Cd-polluted during 12 weeks. The brown rice-polluted with 0.87 ppm Cd (PBR) was sampled from products in the Janghang smeltery area. Diets of brown rice group were brown rice (BR, 0.002 ppm Cd), each 50% of BR and PBR (BR+PBR 50%, 0.44 ppm Cd) and PBR (PBR 100%, 0.87 ppm Cd). To compare with BR+PBR 50%, the another group diet composed the feed (FE, 0.002 Cd ppm) and each 50% of FE and PBR (FE+PBR 50%, 0.44 ppm Cd). Accumulation of Cd, Zn and Cu in blood, liver and kidney rats was measured by GF-AAS. The weight gain in BR groups and FE groups were different 0.22-0.26 and 1.08-1.26 g/day, respectively. Daily intake cadmium was 10.77 and 22.36 ${\mu}g/rat$ in BR+PBR 50% and PBR 100%, and 8.83 ${\mu}g/rat$ in FE+PBR 50%. Cadmium contents in diets were higher, and total intake of the heavy metals was more increased on the whole. Weights of liver and kidney in FE+PBR 50% group was 2.64 and 2.27 folds higher than those in BR+PBR 50% group. Cadmium contents in blood were increased with intake of BR diet, but Zn and Cu were decreased with them. In the diet groups with the same Cd concentration, Cd content of FE+PBR 50% was higher 1.27 times than that of BR+PBR 50%. In the diet group of BR, BR+PBR 50%, and PBR 100%, the increase of Cd concentration was significantly different to the increase of Cd content in the livers. In the same condition of Cd concentration, Cd contents were higher in the BR+PBR 50% group. In the diet groups of BR, BR+PBR 50%, and PBR 100%, the increase of Cd content in the kidneys led to the increase of Zn and Cu contents. In the same condition of Cd concentration, the diet group with the addition of BR was shown to be 3.11 times higher than with the addition of FE. In view of the results so far achieved, It was closely related with Cd, Zn, and Cu content.

• Korean Journal of Food Science and Technology
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• v.46 no.1
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• pp.108-114
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• 2014

To analyze the hazards associated with cucumber and hot pepper cultivation areas, a total of 72 samples were obtained and tested to detect the presence of biological (sanitary indicative, pathogenic bacteria and fungi) and chemical hazards (heavy metals and pesticide residues). The levels of sanitary indicative bacteria (aerobic plate counts and coliforms) and fungi were ND-7.2 and ND-4.8 log CFU/(g, mL, hand, or $100cm^2$) in cucumber cultivation areas, and ND-6.8 and 0.4-5.3 log CFU/(g, mL, hand, or $100cm^2$) in hot pepper cultivation areas. More specifically, the soil of hot pepper cultivation areas was contaminated with coliforms at a maximum level of 5.6 log CFU/g. Staphylococcus aureus was detected only in glove samples at a level of 1.4 log CFU/$100cm^2$ and Bacillus cereus was detected in the majority of samples at a level of ND-4.8 log CFU/(g, mL, hand, or $100cm^2$). Listeria monocytogenes, Escherichia coli O157:H7, and Salmonella spp. were not detected. Heavy metal (Zn, Cu, Ni, Pb, and Hg) chemical hazards were detected at levels lower than the regulation limit. Residual insecticides were not detected in cucumbers; however, hexaconazole was detected at a level of 0.016 mg/kg (maximum residue limit: 0.3 mg/kg) in hot peppers.

• 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.

• The Korean Journal of Malacology
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• v.32 no.4
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• pp.263-268
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• 2016

Metallothionein (MT) family of metal-binding proteins are involved in maintaining homeostasis and heavy metal poisoning. Recently, MT has been considered as a biomarker that can identify a particular species, very similar to the use of cytochrome oxidase I (COI) gene. Satsuma myomphala species of land snails have been reported from North-East Asia, including South Korea and Japan. In particular, the land snail species have been known from only a limited area of Geoje Island, Gyeongsangnam-do province of South Korea. Genetic studies of S. myomphala has been limited with only 6 nucleotide, 2 protein registered on the NCBI server. For elucidating the genetic information of S. myomphala, we conducted RNA sequencing analysis using Illumina HiSeq 2500 next-generation platform. We screened the MT gene from the RNA-Seq database to confirm the molecular phylogenetic relationship. After sequencing, the de novo analysis and clustering generated 103,774 unigenes. After annotation against PANM database using BLAST program, we obtained MT sequence of 74 amino acid residues containing the coding region of 222 bp. Based on this sequence, we found about 53 sequences using the BLAST program in NCBI nr database. Using ClustalX alignment, Maximum-Likehood Tree of MEGA program, we confirmed the molecular phylogenetic relationships that showed similarity with mollusks such as Helix pomatia and H. aspersa, Megathura crenulata.