• Bulletin of Food Technology
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• v.13 no.2
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• pp.3-13
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• 2000

신선 과일, 채소 편의식품의 주요 특징으로는 박피, 절단 등에 의한 식물조직의 손상, 최소가공에 따른 제품의 불확실한 미생물 안전성, 식물 조직의 활발한 물질대사, 제품 종류의 제한 등을 들 수 있다. 따라서 이들 제품에서는 미생물이 증식하기 쉬우나 실제 미생물의 거동은 식물조직의 대사에 의해 영향을 받으며, 또한 생체의 호흡과 필름 포장재의 기체투과도에 의해 좌우되는 포장내부 환경기체에도 영향을 받는다. 수확후 감염은 과일, 채소와같은 원료 농산물의 주요 손실요인으로(Harvey, 1978;Lund, 1983) 신선 과채류 편의식품의 경우 절단면의 노출과 포장내부의 고수분 함량 등에 의해 미생물 감염의 위험은 더욱 더 증가할 수 있다. 특히 대부분의 신선 편의식품이 어떠한 가열처리도 없이 그대로 이용되므로 식품유래 병원균의 오염과 저장중 이들의 증식은 각별한 관심의 대상이 되고 있다. 이에 본고에서는 현재 과채류 편의식품에 주로 사용되고 있는 미생물 오염 방지 또는 조절 방법에대해 설명하고 이의 적용과 관련한 주의사항을 살펴보고자 한다.

• Microbiology and Biotechnology Letters
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• v.16 no.5
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• pp.374-378
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• 1988

Treatability and maximum no inhibitory effect concentration of benzene were measured in the synthetic wastewater medium by the activated sludge in the continuous activated sludge reactor. The maximum no inhibitory effect concentration was 1, 600mg per liter. Benzene concentration over 500mg per liter inhibited the growth of microorganims by the measurment of E/BOD, and the treatability of benzene at the maximum no inhibitory effect concentration was over 95%.

• Journal of Korean Society of Water and Wastewater
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• v.18 no.2
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• pp.113-120
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• 2004

The biodegradability of organics has become essential for the design and modeling of a biological nutrient removal process. Respirometry for the batch test just with wastewater has been conducted to estimate active biomass and readily biodegradable organics in municipal wastewater simultaneously. Municipal wastewater contains significant active biomass, which is estimated about 17% of COD. Compared to the batch test seeded with sludge, the batch test just with wastewater represents a little higher readily biodegradable organics. This might be due to the different environment of the logarithmic growth of active biomass. The nitrate uptake rate test has been also performed for the estimation of the readily biodegradable organics. The nitrate uptake rate test results in a little higher readily biodegradable organics compared to the batch test seeded with sludge and similar organics compared to the batch test just with wastewater. This might be caused by the different sludge of a sequencing batch reactor process. Taking the result of the previous research into account, the readily biodegradable, slowly biodegradable, active biomass, soluble inert, and particulate inert organics are estimated about 11%, 49%, 17%, 11%, and 12% of COD, respectively.

• Journal of the Korean Society for Marine Environment & Energy
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• v.12 no.1
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• pp.1-8
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• 2009

EMMC(Entrapped Mixed Microbial Cell) process which is a kind of active cell immobilizing method was applied to treat fisheries processing wastewater biologically. Kinetic constants were calculated for organic and nitrogen removal and effect of effluent recycling on system performance was evaluated also. Yield coefficient, Y showed relatively low value compared with Y value obtained from conventional activated sludge process. It means that EMMC process can reduce amount of excess sludge significantly compared with conventional activated sludge process. Endogenous respiration coefficient $k_e$ of EMMC process also showed relatively low value compared with that of conventional activated sludge process. Yield coefficient Y, endogenous respiration coefficient $k_e$ and half saturation constant $k_s$ obtained from EMMC process in terms of nitrification were compared with reported value from literature based on suspended growth nitrification system. The value of Y obtained from this study has no difference compared with values obtained from literature review and $k_e$ of this study was low but $k_s$ of this study was high compared than values obtained from suspended growth nitrification system. To evaluate the effect of internal recycling on system performance, system was operated with internal recycling ratio of 1.5Q, 2.0Q, 2.5Q and 3.0Q. increase of internal recycling ratio effect more greatly on improvement of denitrification efficiency than that of nitrification efficiency. Accordingly, optimization of internal recycling ratio has to be based on improvement of anoxic reactor performance.

• Proceedings of the Ginseng society Conference
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• 1984.09a
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• pp.141-144
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• 1984

With microorganism as a single cell model to investigate the cellular effect of total extract of ginseng powder, it was found that ginseng affects cellular respiration biphasically (Tso and Fung, 1980; Tso, 1981). As ginseng is recognized to be a tonic medicinal herb, this finding suggests a possible role of ginseng in altering cellular energy metabolism. Along this line, the same effect on mitochondrial oxygen consumption was studied. It was found that under a controlled pH condition, a significant stimulation of the mitochondrial respiration was observed. This stimulation was ginseng dose-dependent. However, when ginseng was applied at an above threshold concentration, an inhibitory effect was noted. This confirms the previous observation with single cell organism and suggests a universal regulation of energy metabolism effect that transcends cell origin.

• Korean Journal of Soil Science and Fertilizer
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• v.20 no.4
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• pp.375-385
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• 1987

This study was carried out to investigate the effects of pesticides on soil respiration, microflora and enzymes in loam soil, and on pathogenic microorganisms in continuous pepper cropping soil. The results are summarized as follows. No significant effect of pesticides on soil respiration was shown, with the exception of propoxur which slightly increased at $10{\mu}g\;g^{-1}$ treatment. When pesticides were treated, the amount of soil microorganisms generally decreased at the early stage of incubation and the number of microflora was much more decreased at 60-day incubation. When pesticides were treated, the amount of soil enzyme activity was inhibited at the early stage of incubation and gradually recovered at the last stage of incubation. The amount of polygalacturonase activity was increased at the 20-and 30-day incubation in propoxur treatment plot. The amount of ${\beta}$-glucosidase and dehydrogenase activity was increased at 20-and 60-day incubation in carbofuran and acephate treatment plot. The amount of phosphatase activity was increased at 60-day incubation in propoxur and isoprocarb treatment plot. The amount of Fusarium generally decreased in continuous pepper cropping soil, with the exception of isoprocarb and acephate treatment plot which significantly increased. The amount of Pythium increased at 60-day incubation with the exception of captan treatment plot which significantly decreased.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2001.09a
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• pp.57-60
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• 2001

미생물 활성도와 그에 따른 유기물의 분해율은 미생물의 호흡률과 직접적인 관계가 있다. 본 연구는 매립종료후 경과기간이 1년인 Y 매립지와 10년인 C 매립지의 오염특성을 조사하였고, 오염토양 미생물의 산소소비속도를 이용하여 매립종료기간에 따른 오염토양의 산소소비율을 비교 평가 하고자 하였다. C 매립지의 오염토양에 대한 SCO $D_{cr}$ TOC는 Y 매립지에 비해 낮은 함량으로 나타났으나 T-N, N $H_3$-N의 함량은 큰 차이를 보이지 않았다. TOC/T-N비로 보았을 때 Y 매립지에 비해 C 매립지가 낮은 것으로 나타나 연령이 많은 경우 분해성 유기물의 함량은 적은 것으로 판단된다. 산소소비율 실험결과 Y 매립지가 산소소비율이 높은 것으로 나타났으며, C 매립지도 대조토양에 비해 높은 산소소비율을 보였다. 따라서 매립종료 후 경과기간이 10년인 매립지의 미생물의 산소소비율을 보았을 때 여전히 생물학적 안정화가 종료되지 않은 것을 알 수 있었다.

• Korean Journal of Food Science and Technology
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• v.38 no.1
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• pp.47-51
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• 2006

Microorganisms involved in decaying Fuji apples during storage were investigated. Seven pathogens were isolated from the rotted fruits. Penicillium spp. was derived from 65-75% of decayed apples with P. expansum being dominant species. Effects of mild heat treatment on microbial reduction, respiration, and texture characteristics in Fuji apples were examined through hot water dipping at $40-65^{\circ}C$ for varied timε periods. Initial counts of total microorganisms and moulds in fresh fruits s showed 4.75 and 4.66 log CFU/g in a stem, as well as 5.35 and 4.32 log CFU/g in a calyx, respectively. The heat treatment at $40^{\circ}C$ for 180 min significantly reduced the population of total microorganisms and moulds in the fruits. Respiration rate of the apple fruits increased immediately after heat treatment and then returned to the normal level during storage. The rates of ethylene production in the fruits treated at $40-50^{\circ}C$ were maintained lower than that of the untreated control. The fruits treated at $40^{\circ}C$ showed slightly greater flesh firmness than the other apple samples during storage.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.12
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• pp.2175-2185
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• 2000

Respiration rate should be a reasonable state variable for the activated sludge and could be used to simulate the performance of the activated sludge process. Toxic materials are classified into three groups, competitive, noncompetitive and uncompetitive. They increase/decrease the half saturation coefficient or specific growth rate. that means decreasing of the substrate removal capacity. In this research, a pilot-scale activated sludge process was operated under extended aeration method, and a representative noncompetitive inhibitor, acidic wastewater was applied to establish a respirometry-based toxicity model. Using this model. the correlation coefficient between measured and calculated respiration rate was 0.96 when acidic wastewater(pH 3.9~5.5) was introduced continuously to the aeration tank. Even though respiration rate was decreased by toxic effect of acidic wastewater, effluent substrate concentration represented to COD was deteriorated just a little bit. It might be caused by the low ratio of readily biodegradable substrate in the input substrate. Reduction of respiration rate by decreasing of input substrate concentration was much lower than that by acidic wastewater, and hence it was estimated that the possibility of false toxic alarm caused by decreasing of substrate concentration should be low.

• Journal of Wetlands Research
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• v.16 no.3
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• pp.315-325
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• 2014

Valuation of ecosystem services through organic carbon distribution and cycling in the Quercus mongolica forest at Mt. Worak national park were investigated from May 2012 through April 2013. The amount of carbon allocated to above and below ground biomass was 81.94 and 20.53 ton C/ha. Amount of organic carbon in litter layer was 6.49 ton C/ha. Amount of organic carbon within 50 soil depth was 141.23 ton C $ha^{-1}$ $50cm-depth^{-1}$. Total amount of organic carbon in this Quercus mongolica forest was estimated to 250.19 ton C $ha^{-1}$. The estimated amount of won in this Quercus mongolica forest in terms of total organic carbon was about 5.27 million won $ha^{-1}$. The amount of carbon evolved through soil respiration was 7.31 ton C $ha^{-1}yr^{-1}$. The amount of carbon evolved through microbial respiration and root respiration was 3.58 and 3.73 ton C $ha^{-1}yr^{-1}$, respectively. The amount of organic carbon absorbed from the atmosphere of this Quercus mongolica forest was 1.61 ton C $ha^{-1}yr^{-1}$ when estimated from the difference between net primary production and microbial respiration. This amount will come to about 33,000 won $ha^{-1}yr^{-1}$ in Korean currency.