• Journal of Food Hygiene and Safety
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• v.21 no.4
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• pp.250-257
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• 2006

The purpose of this study is to evaluate microbiological contamination of leafy vegetables. Total aerobic bacteria and coliforms were monitored to get the contamination levels and Staphylococcus aureus, Bacillus cereus, Clostridium perfringens, Escherichia coli, Escherichia coli O157:H7, Salmonella spp., Vibrio parahaemolyticus, Listeria monocytogenes, Yersinia enterocolitica, Campylobacter jejuni to detect pathogens with risk of foodpoisoning from fresh vegetables. The colony count of total aerobes and coliforms was also performed to determine the efficacy of washing with tab water by common consumers. 124 samples which are divided into 8 kinds of vegetables - Sesame leaf, Dropwort, Chinese cabbage, Korean leek, Lettuce, Crown daisy, Pimpinella brachycarpa, Chicory were sampled in 2 wholesale markets in Incheon. Mean counts of total aerobic bacteria for individual vegetables ranged from $2.2\times10^6\;CFU/g\;to\;6.0\times10^7\;CFU/g$ and total coliforms were from $4.1\times10^5\;CFU/g\;to\;9.8\times10^6\;CFU/g$. Both show the peaks in summer on this study from March to September. Decrease rates after washing with tab water averaged 81.0% and 82.5% in total aerobic bacteria and coliform counts respectively. Staphylococcus aureus was isolated 8.1%, Bacillus cereus 14.5%, Clostridium perfringens 5.6%, Escherichia coli 18.5%. 11 samples showed overlapped bacterial contamination. For respective vegetables Staphylococcus aureus isolated from 0.0% to 22.2%, Bacillus cereus from 0.0% to 29.4%, Clostridium perfringens from 0.0% to 23.1 %, Escherichia. coli from 0.0% to 35.0%. Escherichia coli O157:H7, Salmonella spp., Vibrio parahaemolyticus, Listeria monocytogenes, Yersinia enterocolitica, Campylobacter jejuni were not isolated. This study is expected to be available as the reference for the basal data of pathogens in fresh vegetables.

• Korean Journal of Soil Science and Fertilizer
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• v.38 no.2
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• pp.108-117
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• 2005

Pharmaceutical byproduct sludge and cosmetic industry wastewater sludge can be used as a raw material of compost. Effects of three types of pharmaceutical byproduct sludge and one type of cosmetic industry wastewater sludge on soil properties and red pepper growth were investigated in a field based concrete pot ($2{\times}2m$). These sludges and pig manure ($5Mg\;ha^{-1}$, dry basis) were incorporated into the upper of loam soil 30 days prior to transplanting red pepper. Changes in soil properties and contents of heavy metals and toxic organic compounds in soil and plant were measured. And also plant growth measurement and bioassay of soil phytotoxicity were included. Contents of heavy metals were increased in the soils treated with the sludges. Plant growth in the sludge treatments were mostly inferior to that of NPK treatment, especially in early stage. Content of N in plant was lower in all sludge treatments at early and middle growth stages, and it was especially caused by characteristics and concentration of nitrogen and organic matter of sludges. Total yield of red pepper was highest in the NPK treatment and followed by pharmaceutical sludge 3, pig manure, pharmaceutical sludge 1, and pharmaceutical sludge 2, and the yield of cosmetic sludge treatment was considerably lower than others. HEM and PAHs contents in soil of cosmetic sludge treatment were $4.80mg\;kg^{-1}$ and $2,263.2{\mu}g\;kg^{-1}$, respectively. Root elongation of lettuce exposed to the water extract of soil treated with cosmetic sludge was about 20% of that found in the test with soil extract of non fertilization treatment. At present, raw materials of compost were authorized according to the contents of organic matter, heavy metals and product processing. Toxic organic compounds analysis and bioassay would be helpful for authorization and assessment of suitability of raw materials of compost.

• Korean Journal of Soil Science and Fertilizer
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• v.38 no.2
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• pp.92-100
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• 2005

This study was conducted to find suitable methods for screening organic resources useful for compost. Twenty-seven industrial and domestic sludges were collected from various cities and industrial areas. Contents of organic matters in the sludges were in the range of 79.3-98.0%, and the contents were much higher than the regulation level (60%) for raw materials of compost. Contents of total nitrogen were in the range of 0.8-2.6%. Contents of Fe and Al were very high. Content of HEM was highest in textile sludge ($257mg\;kg^{-1}$) and the contents in the others were in the range of $12.6-90.3mg\;kg^{-1}$. Content of PAHs was lowest in food sludge ($739.1{\mu}g\;kg^{-1}$ and pulp-mill sludge had the highest PAHs content ($3461.8{\mu}g\;kg^{-1}$). $Microtox^{(R)}$ $EC_{50}$ values were higher in the sludges which were classified as a possible material in composting after analysis and investigation. Lettuce root elongation and $EC_{50}$ values were relatively lower in pulp-mill sludge, sewage sludge 3 (Large city), food sludge and leather sludge. Therefore, mineral nutrients, heavy metals, organic compounds (HEM, PAHs, PCBs), and bioassay ($Microtox^{(R)}$ $EC_{50}$, Relative root elongation test) are recommended to be included in the screening system of raw material of compost in addition to the current regulation with organic matter and 8 heavy metals.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.6
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• pp.1027-1034
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• 2011

In order to provide the basic information on the agricultural environment in Daegwallyeong Highland, the characters of weather, water, and soil quality were investigated. The meteorological characteristics was monitored by automatic weather system (AWS) at 17 sites. The quality of water for samples were collected monthly at 24 sites depending on landuse style. Soil samples were collected from a forest, grassland, and the major vegetable cultivation areas such as potato, carrot, Chinese cabbage, onion, head lettuce, and welsh onion field. The weather showed the mountain climate, and the average yearly temperature is $6.4^{\circ}C$, the average temperature in January is $-7.6^{\circ}C$ and the average temperature in July is $19.1^{\circ}C$, and the change of temperature on the districts of Daegwallyeong is severe. The yearly record of precipitation shows 1717.2 mm. The water quality of crop field was worse than forest or grassland in Daewallyeong highland. In 2005, annual T-N, T-P, SS distribution of Chinese cabbage field showed 7.4~11.3, 0.061~0.1, and $3.0{\sim}53.0mg\;L^{-1}$. The potato field showed 3.1~7.2, 0.019~0.056 and $0.5{\sim}3.0mg\;L^{-1}$, respectively. Being compared of water quality between potato field and chinese cabbage field, it showed that the water quality of Chinese cabbage field was worse than potato field. On farming, the soil of crop cultivation showed pH 5.6 to 6.8, $18.0{\sim}42.4g\;kg^{-1}$ of OM, $316{\sim}658mg\;kg^{-1}$ of Avail. $P_2O_5$. The content of cations showed $0.41{\sim}0.88cmol_c\;kg^{-1}$ of Exch. K, $3.73{\sim}7.07cmol_c\;kg^{-1}$ of Exch. Ca and $1.17{\sim}1.90cmol_c\;kg^{-1}$ of Exch. Mg.

• Korean Journal of Environmental Agriculture
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• v.37 no.4
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• pp.251-259
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• 2018

BACKGROUND: Various culture media have been used for hydroponic cultures of horticultural plants under the smart greenhouses with natural and artificial light types. Management of the culture medium for the control of medium amounts and/or necessary components absorbed by plants during the cultivation period is performed with ICT (Information and Communication Technology) and/or IoT (Internet of Things) in a smart farm system. This study was conducted to develop the cloud-based data analysis system for effective management of culture medium applying to hydroponic culture and plant growth in smart greenhouses. METHODS AND RESULTS: Conventional inorganic Yamazaki and organic media derived from agricultural byproducts such as a immature fruit, leaf, or stem were used for hydroponic culture media. Component changes of the solutions according to the growth stage were monitored and plant growth was observed. Red and green lettuce seedlings (Lactuca sativa L.) which developed 2~3 true leaves were considered as plant materials. The seedlings were hydroponically grown in the smart greenhouse with fluorescent and light-emitting diodes (LEDs) lights of $150{\mu}mol/m^2/s$ light intensity for 35 days. Growth data of the seedlings were classified and stored to develop the relational database in the virtual machine which was generated from an open stack cloud system on the base of growth parameter. Relation of the plant growth and nutrient absorption pattern of 9 inorganic components inside the media during the cultivation period was investigated. The stored data associated with component changes and growth parameters were visualized on the web through the web framework and Node JS. CONCLUSION: Time-series changes of inorganic components in the culture media were observed. The increases of the unfolded leaves or fresh weight of the seedlings were mainly dependent on the macroelements such as a $NO_3-N$, and affected by the different inorganic and organic media. Though the data analysis system was developed, actual measurement data were offered by using the user smart device, and analysis and comparison of the data were visualized graphically in time series based on the cloud database. Agricultural management in data visualization and/or plant growth can be implemented by the data analysis system under whole agricultural sites regardless of various culture environmental changes.

• Korean Journal of Food Science and Technology
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• v.54 no.2
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• pp.218-223
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• 2022

This study, conducted during 2018-2021 in Gangseo, Seoul, monitored residual pesticides in 14 types of fresh-cut produce, including lettuce, tomato, and celery, in wholesale market and supermarkets. A total of 589 cases (2.9%) were inspected; 17 cases (2.9%) were detected within the criteria, and 2 cases (0.3%) exceeded the maximum residual limit (MRL). When assessing the distribution stage of the pesticide violation, there were two violations in the wholesale market (before distribution), which differed from the supermarkets (during distribution). The detected pesticides, mainly insecticides and fungicides, appeared in the order of flubendiamide, flufenoxuron, and diazinon. A violation rate of 0.3% was found for wholesale market, which is collection area dedicated to fresh-cut produce, and this was lower than that for general agricultural products (1.4-2.5%). Since fresh-cut produce are consumed immediately after simple processing, residual pesticides significantly affect the human body; therefore, continuous monitoring of pesticide residues is required.

• Journal of the East Asian Society of Dietary Life
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• v.25 no.5
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• pp.739-751
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• 2015

This study investigated the table settings used in Bul-chun-wi sacrificial rituals in Sangju, Gyeongpook Province. This study took place from May 2014 to April 2015 and incorporated field research and literature review. The subjects of the study were Sojae jongga (family head), Wolgan jongga, Ubook jongga and Ipjae jongga. There were four rows in the table setting of the Wolgan, whereas there were five rows in the other jonggas. In row 5, there were fruits, seeds and confections. In row 4, there were vegetables. In row 3, there was tang (stew); in row 2, juk (steamed meats or fishes) and pyun (rice cake); and in row 1, meh (boiled rice), geng (soup) and myun (noodles). The common food setting was arranged in the order of meh, geng, myun, ganjang (Korean soy sauce), poh (dried meat/fish), chimchae (water kimchi), dates, chestnuts, pears, persimmons, walnuts, bracken, bellflowers, croaker, pyun, and ssam (rice wrapped in lettuce leaves). Ubook jongga had the most number of stews at seven. Sojae and Ipjae jongga each had five stews, and Wolgan jongga had three. The smaller Wolgan jongga had gehjuk (boiled chicken), uhjuk (steamed fish) and yookjuk (boiled meat) arranged in a neat pile on one dish used for rituals, whereas Ubook jongga had gehjuk, uhjuk and yookjuk arranged separately. Sojae and Ipjae jongga had gehjuk arranged separately while yookjuk and uhjuk were arranged as dojuk (gehjuk, uhjuk, yookjuk). The uhjuk was arranged separately. In Wolgan jongga, po was arranged on the right while in the other jonggas, it was arranged to the left. For raw meat Ubook jongga, raw mackerel; Ipjae jongga, raw croaker, and Sojae jongga Yukhoe (beef tartare) were set. However, pork, chicken and croaker were cooked. Other ritual food were used in seasoning and boiling. In the geng Wolgan and Ipjae jongga used miyeokguk (seawood soup), whereas Sojae and Ubook jongga used tangguk (meat soup with vegetables). For the ritual food, most jongga ordered yoogwa, yakgwa and bonpyun as one part, rice cakes (steamed rice cake, glutinous rice cake, jeungpyun, gyungdan), and jehju (alcohol). The other ritual food was prepared on the day by jongga.

• Korean Journal of Microbiology
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• v.47 no.2
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• pp.117-123
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• 2011

The purpose of this study was to evaluate and compare different elution and concentration methods for optimization of human rotavirus (HRV) detection method using real-time RT-PCR and cell culture techniques. The leafy vegetable samples (lettuce, Chinese cabbage) were artificially inoculated with HRV. Viruses were extracted from the vegetables by two different elution buffers, buffer A (100 mM Tris-HCl, 50 mM glycine, 3% beef extract, pH 9.5) and buffer B (250 mM Threonine, 300 mM NaCl, pH 9.5), and the extracted viruses were concentrated by filtration and PEG precipitation sequentially. To determine infectivity of the viruses, the viruses recovered from the samples were infected to the MA-104 cells, and integrated cell culture real-time RT-PCR was performed at 1, 48, 72, 96, 120, 144, 168 h post-infection (p.i.). The elution buffer A was more efficient in extracting the virus from the produce samples tested than the buffer B, 29.54% and 18.32% of recoveries, respectively. The sensitivity of real-time RT-PCR method was markedly improved when the virus was concentrated by the filtration method. When the viruses were eluted and concentrated by buffer A and filtration, respectively, the average recovery rate was approximately 51.89%. When the viruses recovered from samples were infected to MA-104 cell, infectious HRV was detected within 48 h p.i. by ICC/real-time RT-PCR, whereas cytopathic effects were not observed until 72 h p.i. The optimized detection method evaluated in this study could be useful for rapid and reliable detection of HRV in fresh produce products and applied for detection of other food-borne viruses.

• Journal of Food Hygiene and Safety
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• v.27 no.2
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• pp.169-175
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• 2012

Five kinds of selective media, such as mannitol salt agar (MSA), Baird-Parker agar (BPA), Baird-Parker supplemented with rabbit plasma fibrinogen (BPA+RPF), CHROMagar Staphylococcus aureus (CSA), and Petrifilm Staph Express count system (Petrifilm), were compared to recommend the optimum selective media for isolation of Staphylococcus aureus from agricultural products. Seventy four target and non target bacteria were inoculated on five selective media to analyze sensitivity and specificity. In the recovery test of injured S. aureus cells, S. aureus was exposed to acid (1% lactic acid for 10 min), heat ($60^{\circ}C$ for 90s), and cold ($-20^{\circ}C$ for 1h) conditions. And artificially contaminated agricultural products (iceberg lettuce, green pepper, and cherry tomato) was enumerated on five selective media. The sensitivity of BPA+RPF, CSA, Petrifilm, MSA, and BPA were 100%, 100%, 100%, 90.5%, 90.5%, respectively. In addition, the specificity of BPA+RPF, CSA, MSA, BPA and Petrifilm were 100%, 100%, 84.6%, 75.0%, 67.3%, respectively. However, no difference among five selective media was observed in recovery on injured S. aureus cell and enumeration from agricultural products. This results suggest that BPA+RPF and CSA are the optimum media for detection of S. aureus from agricultural products.

• Korean Journal of Plant Resources
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• v.27 no.5
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• pp.546-555
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• 2014

The final aim of this study is to develop a biofiltration system integrated with plant vegetation for improving indoor air quality effectively depending on indoor space and characteristics. However, to approach this final goal, several requirements such as constant pressure drops (PDs) and soil moisture contents (SMCs), which influence the capacity design for a proper ventilation rate of biofiltration system, should be satisfied. Thus, this fundamental experiment was carried out to adjust a proper wind speed and to ensure a stabilization of initial SMCs within biofilter for uniform distribution of SMCs and PDs, and for normal plant growth, especially avoiding root stress by wind. Therefore, we designed horizontal biofliter models and manufactured them, and then calculated the ventilation rate, air residence time, and air-liquid ration based on the biofilter depending on three levels of wind speed (1, 2, and $3cm{\cdot}s^{-1}$). The relative humidity (RH) and PD of the humidified air coming out through the soil within the biofilter, and SMC of the soil and plant growth parameters of lettuce and duffy fern grown within biofilter were measured depending on the three levels of wind speed. As a result of wind speed test, $3{\cdot}sec^{-1}$ was suitable to keep up a proper RH, SMC, and plant growth. Thus, the next experiment was set up to be two levels of initial SMCs (low and high initial SMC, 18.5 and 28.7%) within each biofilter operated and a non-biofiltered control (initial SMC, 29.7%) on the same wind speed ($3cm{\cdot}sec^{-1}$), and measured on the RH and PD of the air coming out through the soil within the biofilter, and SMC of the soil and plant growth parameters of Humata tyermani grown within biofilter. This result was similar to the first results on RHs, SMCs, and PDs keeping up with constant levels, and three SMCs did not show any significant difference on plant growth parameters. However, two biofiltered SMCs enhanced dry weights of the plants slightly than non-biofiltered SMC. Thus, the stability of this biofiler system keeping up major physical factors (SMC and PD) deserved to be adopted for designing an advanced integrated biofilter model in the near future.