• Journal of the Korea Organic Resources Recycling Association
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• v.17 no.4
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• pp.36-47
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• 2009

Microbial and related biochemical mass of composts are important for optimization of its process and end-products. This study was carried out to assess the specific microbial and related biochemical mass which could be used as an indicator for compost maturity during composting stages. The samples from five compost plants were collected at three stages (Initial, Thermophilic and Mature) and analyzed for total aerobic bacteria (TAB), Coliforms, Escherichia coli, Actinomycetes and fungi. Significantly, the coliforms and E.coli counts decreased during the thermophilic stage and were completely eliminated during mature stage. However, the other microbial mass were completely eliminated during mature stage. Which disclosed that Coliforms and E.coli communities can be used as compost maturity indicator. Interestingly, the microbial biomass carbon and nitrogen ratio (MBC/MBN) were decreased a little during the thermophilic stage due to the decreasing number of coliforms, Ecoli and fungi, while the ratio increased during the mature stage due to increasing fungal and aerobic bacterial counts. In addition the heavy metals were shown strong negative correlation with Actenomycetes. This study provides insight to the evaluation of compost maturity as well as the quality by the metal-microbial interactions.

• Journal of Food Hygiene and Safety
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• v.32 no.5
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• pp.396-403
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• 2017

The purpose of this study was to investigate water quality for irrigation water used in Napa cabbage cultivation. The water samples were analyzed for physiochemical and microbiological quality for a total of 111 samples including surface water (n = 75) and groundwater (n = 36) collected from five different regions where Napa cabbage is massively grown. As a conclusion, the levels of fecal indicators for surface water were higher than those for groundwater. The numbers of coliform from surface water and groundwater were 1.96-4.96 and 0-3.98 log MPN/100 mL, respectively. Enterococci were detected in 95% (72/75) of surface water samples and 22% (8/36) of groundwater samples. Besides, 97% (73/75) of surface water samples were observed being contaminated with Escherichia coli, and 22% (8/36) of groundwater sample was positive for E. coli. In the case of surface water, E. coli and coliform correlate to T-P, and enterococci showed relevance to the suspended solid (SS) and biochemical oxygen demand (BOD). In groundwater, fecal indicator bacteria showed relevance to the SS and chemical oxygen demand (COD). These results could be provided as fundamental date for establishing microbial standard of water used in leafy vegetables cultivation.

• Restorative Dentistry and Endodontics
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• v.30 no.1
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• pp.16-21
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• 2005

The purpose of present study was to compare the speed of coronal leakage before and after post space preparation using Streptococcus mutans. Forty straight extracted human teeth were selected. The crowns were removed to a uniform remaining root length 14 mm. Canals were enlarged by 06 taper $Profiles^{(R)}$ to a size $\#40$ as a master apical file. And these were filled with gutta percha point and $Tubuliseal^{(R)}$ sealer, using continuous wave technique. Groupings are as follows. Group 1 - These teeth were obturated without sealer. Group 2 - These teeth were obturated and covered the surface of the root completely with sticky wax. Group 3 - These teeth were obturated. Group 4 - These teeth were obturated and prepared for post space remaining 5 mm of gutta percha. The teeth were suspended in plastic tubes. The upper chamber received the bacterial suspension everyday to simulate clinical situation. The lower chamber consisted of BHI added Andrade's indicator. All roots in the positive control group (Group 1) turned yellow within 24 h and those of negative control group (Group 2) remained red throughout the experimental period (70 days) The samples of group 3 were contaminated within an average of 27.2 days. The samples of group 4 were contaminated within an average of 15.7 days, ranging from 9 to 22 days. There was significant difference between group 3 and group 4 statistically (p < 0.05).

• Journal of Environmental Health Sciences
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• v.40 no.1
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• pp.63-70
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• 2014

Objective: The purpose of this study was to investigate the occurrence of indicator organisms in essential sanitary ware in public restrooms. Methods: Twelve public restrooms were randomly selected. Samples at three locations (toilet seat, toilet flush handle/lever, and faucet handle) in the restrooms were collected with moistened-sterile cotton swabs and applied to media in order to determine aerobic colony count (ACC), total coliforms, and Escherichia coli. Results: Most of the samples taken in summer showed a higher level of ACC than those taken in winter (p<0.05). Female restrooms showed higher ACC levels on faucet handles and male restrooms on toilet flush handles/levers (p<0.05). Overall, faucet handles contained the greatest level of ACC, followed by toilet seats, whereas the least load was found on toilet flush handles/levers. The ACC level of samples in the restrooms in public parks, subway stations, and educational institutions varied. Total coliforms were identified in about 20% of toilet seats and faucet handles in male restrooms and faucet handles in female restrooms in summer. These locations were also the sites of positive results of E. coli isolation. Conclusions: The public restrooms were significantly more contaminated in summer than in winter. Overall, the most contaminated locations in the restrooms were toilet seats in male restrooms, and faucet handles in female restrooms. Poor hygienic status was indicated by the positive results of total coliforms and E. coli on samples from some sites. Therefore, sanitary control of restrooms should be improved. These results should be confirmed in a larger study that includes more public restrooms.

• The Korean Journal of Quaternary Research
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• v.19 no.2
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• pp.35-37
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• 2005

Sediment samples from five stations at the Shihwa Lake sewage outfall, west coast of Korea, were collected to evaluate the effect of the outfall on benthic foraminifera. Heavy metal (Cu and Zn) polluted eastern part of the Shihwa Lake, adjacent to the Shihwa-Banwol Industrial Complexes, shows barren or nearly barren of benthic foraminifera, and the lowest number of species both at the core top and downcore. Excepting for the barren zone, pyritized benthic foraminifera abundantly occur both at the surface and downcore sediments in the western part of the Shihwa Lake, suggesting that foraminiferal disease by anoxic bacteria. Recent intrusion of pollutants from the Shihwa-Banwol Industrial Complexes and adjacent six major streams severely polluted the Shihwa Lake as shown by the low abundance (number/10 g) of benthic foraminifera, low number of A. beccarii, low species diversity, and absence of both Elphidium spp. and ostracodes at the surface sediments compared to the downcore. Except the barren zone, both pyritized and non-pyritized Ammonia beccarii occur dominantly in the surface sediments and downcore. Elphidium spp. (either pyritized or non-pyritized) do not occur in the surface sediments of whole stations. However, they occur from the entire downcore sediments except in the eastern part of Shihwa Lake. Arenaceous foraminifera do not inhabit in the heavily polluted areas as evidenced by the occurrence of relatively deep core depth (11-50 cm). Ostracodes occur at the downcore sediments, but they do not occur at the surface sediments. Ostracodes also do not occur at the heavily polluted areas in the eastern part of the Shihwa Lake both at the surface and downcore sediments, indicating that the abundance of ostracodes also can be used for a pollution indicator.

• Journal of Microbiology and Biotechnology
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• v.16 no.11
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• pp.1706-1712
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• 2006

Because of the need for new antimicrobial substances with novel mechanisms of action, we report here the use of an Acinetobacter reporter system for high-throughput screening of active antimicrobial agents. The bioreporter Acinetobacter strain DF4/PUTK2 carrying luciferase genes luxCDABE was chosen because of its ecological importance and it is widespread in nature. This bioreporter is genetically engineered to emit light constitutively that can be measured in real time by luminometry. Hence, this reporter system was employed to determine the bacteriostatic actions of spent-culture supernatants derived from twelve bacterial isolates. Out of the results, the strongest bioluminescence inhibitory effect of the supernatants was recorded with Bacillus cereus strain BAC (S5). Subsequently, ethyl acetate extracts of extracellular products of strain BAC (S5) were separated by a thin-layer chromatography (TLC). Based on the bioluminescence inhibitory assay, three fractions were found to have antimicrobial activity. One fraction (C) having the strongest antimicrobial activity was further purified using TLC and characterized by IR, $^1H$ NMR, mass spectrometry, SDS-PAGE, and amino acid composition analysis. The results predicted the presence of 2-pyrrolidone-S-carboxylic acid (PCA) and the octadeconic-acid-like fatty acid. Fraction C also demonstrated a broad inhibitory activity on several Gram-negative and Gram-positive bacteria. In conclusion, the Acinetobacter reporter system shows great potential to be a reliable, sensitive, and real-time indicator of the bacteriostatic actions of the antimicrobial agents.

• International Union of Geodesy and Geophysics Korean Journal of Geophysical Research
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• v.26 no.1
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• pp.59-73
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• 1998

Sediment samples from five stations at the Shihwa Lake sewage outfall, west cost of Korea, were collected to evaluate the effect of the outfall on benthic foraminifers. Heavy metal (Cu and Zn) polluted the eastern part of the Shihwa Lake, adjacent to the Shihwa-Banwol Industrial Complexes, shows barren or nearly barren of benthic foraminifers, and the lowest number of species both at the core top and downcore. Excepting for the barren zone, pyritized benthic foraminifers abundantly occur both at the surface and downcore sediments in the western part of the Shihwa Lake, suggesting that foraminiferal disease by anoxic bacteria. Recent intrusion of pollutants form the Shihwa-Banwol Industrial Complexes and adjacent six major streams severely polluted the Shihwa Lake as shown by the low abundance (number/10 g) of benthic foraminifers, low number of Ammonia beccarii, low species diversity, and absence of both Elphidium spp. and ostracodes at the surface sediments compared of both downcore. Except the barren zone, both pyritized and non-pyritized Ammonia beccarii occur dominantly in the surface sediments and downcore. Elphidium spp. (either pyritized or non-phyritized) do not occur in the surface sediments of whole stations. However, they occur from the entire downcore sediments except in the eastern part of Shihwa Lake. Arenaceous foraminifers do not inhabit in the heavily polluted areas as evidenced by the occurrence of relatively deep core depth (11-15 cm). Ostracodes occur at the downcore sediments, but they do not occur at the surface sediments. Ostracodes also do not occur at the heavily polluted areas in the eastern part of the Shihwa Lake both at the surface and downcore sediments, indicating that the abundance of ostracodes also can be used for a pollution indicator.

• Journal of Korean Society on Water Environment
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• v.22 no.2
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• pp.271-276
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• 2006

The outbreak cases of Cryptosporidium or Giardia from drinking water in abroad have drawn attentions on the public health. It is well known that Cryptosporidium is the most resistant organism against chlorine disinfection. To guesstimate the levels of Cryptosporidium and Giardia in Korean surface water, 1~2 samples from 22 drinking water sources in four Korean major rivers of Han, Keum, Nakdong, and Youngsan were monitored. In addition, two sites in Kyunganchon, a contaminated river were monitored for comparison. In source waters, detection rates of Cryptosporidium and Giardia were 15% (6/39) and 21% (5/24) with the range of 1~3 oocysts/10 L and 1~6 cysts/10 L, respectively. In Kyunganchon, they were 60% (6/10) and 70% (7/10) in the range of 1~9 oocysts/10 L and 10~72 cysts/10 L, respectively. When one of the source waters in Han river was monitored monthly, Cryptosporidium were found mostly in cold season. Matrix of the samples gave influence on the recoveries of the spiked protozoa. The recoveries of both Cryptosporidium and Giardia increased in the samples of Kyunganchon, known as contaminated area. However, protozoan recovery did not show significant relation with turbidity, the index of matrix contamination, which implies that there are additional unveiled features of matrix affecting the recoveries of the protozoa. The protozoan distribution in Kyunganchon showed significant relations with Cl. perfringens, anaerobic and spore forming indicator bacteria of fecal contamination by regression analysis, but not with turbidity, the general indicator of water quality.

• Asian-Australasian Journal of Animal Sciences
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• v.23 no.10
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• pp.1319-1324
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• 2010

The objectives of this study were to compare the effectiveness of different indicators of mammary inflammation in buffalo and to evaluate the association of the indicators with buffalo milk yield, composition, and rennet coagulation properties. This study was carried out at four buffalo farms in central Italy using a total of 50 lactating buffalo. Milk from each buffalo was tested at the beginning, middle, and end of lactation. To evaluate the relationship between mastitis markers and milk components, three classes were defined for each of the following markers: total somatic cell count (TSCC), differential somatic cell count (DSCC), and bacteriological results The regression coefficient for the reference method and the alternative method of determining TSCC was 0.81, indicating that the method routinely used to analyze buffalo milk consistently underestimated actual TSCC. The milk samples positive for udder-specific bacteria also had higher TSCC values than the samples that were negative for bacteria ($872{\times}10^3$/ml vs. $191{\times}10^3$/ml). In samples that were positive for udder-specific bacteria, polymorphonuclear leukocytes (PMN) made up greater than 50% of the cells. Moreover, only 1% of the samples in the lowest TSCC class were positive for bacteria. The correlation between TSCC and PMN was stronger (0.70), and PMN values in buffalo milk increased significantly when the TSCC class changed from low (38%) to medium and high (56% and 64%). Milk yield was negatively related to TSCC. Significant changes in lactose (4.87%, 4.80% and 4.64%) and chloride content (0.650 mg/ml, 0.862 mg/ml and 0.882 mg/ml) were also observed with increasing TSCC values. Higher TSCC was associated with impaired rennet coagulation properties: the clotting time increased, while the curd firming time ($p{\leq}0.05$) and firmness decreased. We concluded that in buffalo as in dairy cows, TSCC is a valid indicator of udder inflammation; we also confirmed that a value of $ 200{\times}10^3 cells/ml should be used as the threshold value for early identification of an animal affected by subclinical mastitis. In addition to its association with significantly decreased milk yield, a TSCC value above this threshold value was associated with changes in milk composition and coagulating properties.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.2
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• pp.328-332
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• 2014

A survey was conducted on the isolation of lactic acid bacteria with antibacterial activity to extend kimchi shelf-life. Antibacterial activity was tested against bacteria associated with acidification of kimchi, including Lactobacillus plantarum, Pediococcus pentosaceus, and Lactobacillus sakei, using agar-well diffusion assay. Two isolates from kimchi were identified as Lactococcus lactis subsp. lactis and Lactobacillus brevis by 16S rRNA gene sequence analysis and API 50 CHL assay, and they showed antibacterial effects against indicator strains. The isolates displayed acid tolerance at pH 3.5, salt tolerance in 5% NaCl, and growth at $4^{\circ}C$. These result imply that the selected strains might be used to extend kimchi shelf-life as a potential starter.