• Journal of Applied Biological Chemistry
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• v.59 no.4
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• pp.299-304
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• 2016

When used for amplicon sequencing, Illumina platforms produce more than hundreds of sequence artefacts, which affects operational taxonomic units based analyses such as differential abundance and network analyses. Nevertheless it has become a major tool for fecal microbial community analysis. In addition, results from sequence-based fecal microbial community analysis vary depending on conditions of samples (i.e., freshness, time of storage and quantity). We investigated if freeze-drying samples could improve quality of sequence data. Our results showed reduced number of possible artefacts while maintaining overall microbial community structure. Therefore, freeze-drying feces prior to DNA extraction is recommended for Illumina-based microbial community analysis.

• Proceedings of the Korea Water Resources Association Conference
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• 2016.05a
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• pp.124-124
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• 2016

하천에서의 분변성대장균은 분변성 오염 정도를 나타내는 지표로서, 이 농도가 높을수록 오염된 하천수와의 접촉을 통한 호흡기, 소화기 및 피부 관련 질병의 발발 확률이 높다고 알려져 있다. 따라서 하천에서의 수영, 수상스키 등과 같은 입수형 친수활동을 할 때, 분변성대장균 농도가 농도 기준 이하인지를 확인하고 이러한 정보를 친수활동에 이용할 필요가 있다. 그러나 분변성대장균의 경우, 현재 자동수질측정망에서 측정되고 있는 다른 수질인자들과는 달리 실시간 측정이 불가능하다고 알려져 있다. 분변성대장균을 측정하는데 있어 최소 18시간 이상이 필요하며, 이러한 분변성대장균 측정 방식은 하천 이용자들이 안전한 친수활동을 영위하는데 있어 적절한 수질 정보를 제공하지 못한다. 그러므로 분변성대장균을 예측하는 모델을 개발하고, 이를 이용하여 실시간 분변성대장균 정보를 생성하여 하천 이용자들에게 제공할 필요가 있다. 본 연구에서는 친수활동이 활발하게 이루어지는 곳 중 하나인 북한강의 대성리 지점에 대해 데이터 기반 모델을 이용하여 분변성대장균을 예측하였다. 데이터 기반 모델은 물리 기반 모델에서 필요한 지형데이터나 비점오염원 등의 초기 오염물의 양에 대한 데이터를 필요로 하지 않고, 대신 독립변수로 사용되는 기상 및 수질데이터를 필요로 한다. 이러한 기상 및 수질데이터는 기존 기상관측소, 수질관측소에서 매일 자동으로 측정되기 때문에 데이터 기반 모델은 물리 기반 모델에 비해 입력데이터를 구성하기가 쉽다는 장점을 지닌다. 이러한 데이터 기반 모델 중 분류 모델은 회귀 모델과 달리 분변성대장균 농도가 일정 수질기준 이상을 넘는지를 바로 예측할 수 있다. 본 연구에서는 분류 모델 중 높은 예측력을 가진다고 알려진 랜덤포레스트(random forest) 기법을 이용하여 분변성대장균 예측 모델을 개발하였다. 분변성대장균 예측 모델은 주어진 기상 및 수질 조건에 대해 분변성대장균이 200 CFU/100ml가 넘는지를 예측하였다. 예측된 분변성대장균이 기준을 넘는 경우를 2등급, 넘지 않는 경우를 1등급으로 명명하였다. 모델을 개발하기 위하여 북한강 대성리 인근 측정소에서 2010년부터 2015년까지 측정된 기상 및 수질데이터를 수집하였다. 수집한 데이터를 훈련 및 검증데이터로 샘플링하였으며, 이 때 샘플링한 데이터가 기존 데이터가 가지고 있던 등급별 비율을 유지하기 위하여 층화샘플링을 하였다. 본 연구에서는 샘플링에 의한 불확실성을 줄이기 위하여 랜덤하게 50번 샘플링된 각각의 훈련데이터에 대해 모델을 개발하였다. 50개의 모델의 검증 결과를 종합한 결과, 전체 예측률은 0.139로 나타났다.

• Journal of the Korean Society for Marine Environment & Energy
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• v.4 no.3
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• pp.40-52
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• 2001

Using a biochemical indicator, the effects of fecal pollution in the estuary of the Nakdong river and in the Chinhae Hay were investigated from summer to winter in 1997-1998. The biochemical indicator used in this study was coprostanol (5-cholestan-3-ol) which is a kind of fecal sterol. It is a useful tracer of fecal pollution, as it is only found in feces of mammals including humans. Coprostanol was less affected by surrounding environments than other indicators of fecal pollution such as fecal coliform or ammonium and was proved to be a good indicator of fecal pollution. Therefore, long-term observations of coprostanol and related compounds could be used as useful indicators for the effects of feces on marine environments and ecosystems.

• Journal of Veterinary Clinics
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• v.19 no.3
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• pp.295-298
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• 2002

This study was conducted to develope noninvasive fecal PCR assay for detecting the Helicobacter species in dogs. From the DNA isolated from fecal samples, and a region of the 16S rRNA gene conserved among Helicobacter spp. was amplified In comparison with gastric biopsy test, the fecal PCR assay showed high specificity(100%) and sensitivity(96%). The prevalence of Helicobacter spp. infection in privately owned pet dogs in Korea detemined by the fecal PCR assay was 72.1%. the fecal PCR assay determined in this study can a new noninvasive test detecting Helicobacter spp. infection in dogs.

• Parasites, Hosts and Diseases
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• v.32 no.1
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• pp.7-12
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• 1994

A calf and 50 mice were infected with Cryptosporidium parvum and their fecal materials were collected and treated 10 ether extraction (EE), followed by discontinuous sucrose gradients (DSG) method. EE method was to remove some of fat or lipid from feces. Sediments were washed by centrifugation ($1,500{\;}{\times}{\;}g$ for 10 min., 3 times) In phosphate-buffered saline and then these washed sediments were sleeved sequentially through stainless steel screens with a final mesh of 250 ($61{\;}{\mu\textrm{m}}$ porosity) to remove other debris. After sieving, the materials were suspended in 2.5% potassium dlchromate solution. Oocysts were counted by using a hemocytometer and the recovery rate of pure oocysts was calculated on the basis of the count. Following centrifugation ($1,500{\;}{\times}{\;}g$ for 30 min.) by DSG method, most oocysts were recovered at the interface between a gravity of 1.103 and 1.064. The recovery rates of pure oocysts from the fecal suspension of the calf ($3.8{\;}{\times}{\;}10^7/ml$) and the mouse ($3.2{\;}{\times}{\;}10^6/ml$) treated with EE method were 81.6% and 51.6%, respectively. It is suggested that the recovery rate was dependent on the number of oocysts In each suspension treated with EE method. To get the 50% recovery rate, there must be more than $2{\;}{\times}{\;}10^6$ oocysts per ml of the fecal suspension treated with EE method. By the combination of the two methods it was possible to isolate C. parvum oocysts from normal feces of the calf and mouse as well as from dlarrhelc feces.

• Journal of the Korea Organic Resources Recycling Association
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• v.1 no.2
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• pp.237-258
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• 1993

Objectives in this study are to stabilize the organic sludges which were produced from papermill wastewater, nightsoil treatment facilities and utilized as foods for earthworm, to find the method for using the cast which was orginated by earthworm as fertilizer, and ultimately to develop the practical technique to solve the environmental problems by optimization of wastes treatment. The results of this study were summarized as follows. In the investigation for fertilizer effect of cast, germination rates of cucumber, tomato, and cabbage were investigated. The germination status of 3 types of plants was excellent as over 90% in the combination case of 30-45% cast. In the investigation for fertilizer effect of cast derived from nightsoil sludge, the growing status of cucumber, tomato, and cabbage was excellent in the combination case of 30-45% cast. In the experiment for fertilizer effect investigation of cast derived from papermill sludge, the growing status of cucumber, tomato, and cabbage was excellent in the combination case of 30-45% cast. Also, in the combination case of 60% cast, plants growth was not disturbed.

• Journal of Wetlands Research
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• v.16 no.4
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• pp.443-452
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• 2014

Feces contain nutrients such as nitrogen and phosphate, potassium and research of the impact on the environment from feces is very diverse. However, despite the importance of mammals to environment, studies of mammals into the terrestrial ecosystems are rare. Korean water deer (Hydropotes inermis) is an endemic species of Korea and China, and we conducted on factor of plant growth in relation to feces of Korean water deer depending on land use patterns. The analysis of growth, biomass and C/N ratio of Zea mays, amount of feces and land use patterns are strongly affecting the C/N ratio and growth of the Zea mays. The quantity of the feces also influences the growth of plants instead of the land use patterns. Furthermore, the feces of Korean water deer have a lower C/N ratio than that of other animals' feces. Being the process of composting, it is able to serve a suitable fertilizer for a crop growth. In this study, we investigated the impact of feces into the environment in the terrestrial ecosystems and we were able to provide the basic data to the resources of an efficient scheme of animal feces. Further research is needed to quantify the materials amongst the plant, soil and animal, and to understand the relationship ecosystem.

• Journal of the Korea Organic Resources Recycling Association
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• v.4 no.2
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• pp.55-62
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• 1996

The purpose of this study is the evaluation of adsorption capacity of casts for heavy metals comparing with the activated carbon. The casts was obtained from vermicomposting of the mixed organic sludges which were generated from the treatment facilities for leather wastewater and cattle wastewater. The physico-chemical characteristics of cast was investigated. Also, the batch adsorption experiments of cast and activated carbon for heavy metals were carried out, and the results were analyzed by Freundlich isotherm. The buffering capacity to the acidic wastewater was founded in the cast, and the cation exchange capacity of cast impling adsorption capacity for soluble substances was evaluated as about 55me/100g. Those were implied that the cast have a large potential as a good adsorbent for soluble pollutants in wastewater. From the results of batch experiments, the removal efficiencies of tested various heavy metals including Pb, Cu, Cd, and Cr were very high value as 89-98% for the activated car-bon, and 80~95% for the casts except for Zn. The adsorption equilibriums for the two materials were achieved within 90 minutes. The order of preferable metals in the adsorption was found to be Pb>Cu>Cd>Cr>Zn on the cast and to be Pb>Cd>Cu>Cr>Zn on the activated carbon, respectively. From the above results, it might be con-cluded that cast is effectively available as a good adsorbent to treating the heavy metal bearing wastewater.

• Korean Journal of Environmental Biology
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• v.26 no.3
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• pp.264-269
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• 2008

This study was intended to test the feasibility of genetic analysis of wintering population of geese using their feces samples. This noninvasive approach is quite significant and effective because we do not need to capture or harm geese to obtain the samples. We collected the feces from two different populations of wintering geese in Korea in 2007. Finally thirty two feces were analyzed through a molecular genetic method. As a result, 14 haplotypes were identified and classified into two groups, white-fronted geese (Anser albifrons) and bean geese (Anser fabalis). We established the method to make molecular genetic experiment more efficient using the feces. This study has a significance as the first genetic result on wintering population of geese in Korea using noninvasive sampling method.

• Journal of Wetlands Research
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• v.17 no.1
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• pp.1-10
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• 2015

The bleaching phenomenon of otter spraints is indicates that the age of spraints (fresh or old spraints). As previous studies on the old otter faeces (spraint) have focused only on the external changes of spraints, it has been difficult to explain the difference of the decomposition rates among old spraints. We hypothesized that the micrometeorology difference caused by various characteristics of sprainting sites such as porosity and consistency of soil could affect the extent of the decomposition rate, the solar bleaching phenomenon of spraints used as a measure of the patterns of old spraints. Sprainting sites were classified into four types (Clay, Sand, Rock and Concrete spot) and each type was divided into two groups according to the sunlight condition (Sunny site and Shady site) to measure the effect of solar radiation. Micrometeorology of the sites were evaluated by measuring temperatures and humidities of the sites during the whole season. The variations in micrometeorology of the sunny sites according to the sprainting site types were examined with correlation analyses between the factors of micrometeorology. The analyses on the bleaching phenomenon of the spraints by micrometeorology showed that the highest rate of bleaching was found at the 'Rock spot' and 'Concrete spot' of the sunny site and especially in summer, the highest rate of bleaching ($63.4{\pm}7.6%$) was found at the 'Clay spot' of the sunny sites. The lowest rate of bleaching was found at the 'Sand spot' of the sunny sites. The above findings show that the difference in bleaching rates among sprainting sites was due to the seasonal or sunny condition. In addition, we found that the differences in thermal conductivity among sprainting site characteristics have resulted in different sprainting site temperature which have affected the rate of bleaching of spraints. In conclusion, this study suggests that studies of otters on their population size and home ranges using spraints as an indirect sign, should consider the effects of sprainting site characteristics and weather conditions.