• Journal of Plant Biology
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• 제10권1_2호
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• pp.21-30
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• 1967

The aim of present study is to elucidate the relationship between decay rate of soil organic matter, and the change of soil microbial population under the oak and pine forest soils in Kwang-nung plantation stand. The results obtained are as follows: 1) The correlation coefficient between decay rate and the soil bacteria is 0.84 and fungi 0.93. 2) The distribution of soil microbial population is higher in both F horizon of the oak forest soil, and F and H horizon of the pine forest soil. However, the number of soil microorganisms decreases with the depth in each forest soil. 3) The population of soil microbes is related to moisture content, total nitrogen, available phosphorus, and exchangeable calcium, except organic carbon in fungi. 4) The soil organic matter has been mainly decomposed by fungi, and the size of its population are governed by the factors such as moisture content, organic carbon, total nitrogen, available phosphorus, and exchangeable calcium.

• 미생물학회지
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• 제6권3호
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• pp.92-92
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• 1968

1) The aim of present investigation is to elucidate the relation of the balance of the production and decomposition of the fir litter. in Kwangnung plantation stands. 2) The decay constant, K, of litters was 0. 185 for the fir stand at Kwangnung. 3) The mode for the accumulation of organic carbon ($C_a$) is $c_a$= $610(1-e^{-0.185t})$), and for the decay of organic carbon (C) C = $610(1-e^{-0.185t})$. 4) The time required for the decay of half of the accumulated organic carbon in the fir stand is 3. 74 years and for 99% of elimination 27.02 years. 5) The litters of Abies holophylla killed by heat and washed with alcohol-benzol, with hot water, or with both alcohol-benzol and hot water were incubated after inoculated with suspension of firwood soil. Plate counts were made of fungi and bacteria from time to time. 6) Removal of the alcohol-benzol soluble substance stimulates at the beginning of the decay the growth of fungi and also of bacteria. 7) Removal of the water soluble fraction is detrimental to the growth of fungi in particular. 8) The distribution of soil microbial population is higher in both F and H horizon of the fir plantation soil in Kwangnung. However, the number of soil microorganisms decreases with the depth in forest soil.

• 미생물학회지
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• 제6권3호
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• pp.93-99
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• 1968

1) The aim of present investigation is to elucidate the relation of the balance of the production and decomposition of the fir litter. in Kwangnung plantation stands. 2) The decay constant, K, of litters was 0. 185 for the fir stand at Kwangnung. 3) The mode for the accumulation of organic carbon ($C_a$) is $c_a$= $610(1-e^{-0.185t})$), and for the decay of organic carbon (C) C = $610(1-e^{-0.185t})$. 4) The time required for the decay of half of the accumulated organic carbon in the fir stand is 3. 74 years and for 99% of elimination 27.02 years. 5) The litters of Abies holophylla killed by heat and washed with alcohol-benzol, with hot water, or with both alcohol-benzol and hot water were incubated after inoculated with suspension of firwood soil. Plate counts were made of fungi and bacteria from time to time. 6) Removal of the alcohol-benzol soluble substance stimulates at the beginning of the decay the growth of fungi and also of bacteria. 7) Removal of the water soluble fraction is detrimental to the growth of fungi in particular. 8) The distribution of soil microbial population is higher in both F and H horizon of the fir plantation soil in Kwangnung. However, the number of soil microorganisms decreases with the depth in forest soil.

• 상하수도학회지
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• 제30권1호
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• pp.9-17
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• 2016

Disinfectant/oxidation process is a crucial process in water treatment for supplying safe drinking water. Chlorination is still widely used for water treatment area due to its effectiveness on microbial inactivation and economic feasibility. Recently, disinfection concern in marine environment is increasing, for example, movement of hazardous marine organism due to ballast water, marine environmental degradation due to power plant cooling water discharge, and increase of the amount of disinfectant in the offshore plant. It is needed to conduct the assessment of disinfectant behavior and the development of disinfectant prediction model in seawater. The appropriate prediction model for disinfectant behavior is not yet provided. The objective of the study is to develop chlorine decay model in seawater. Various model types were applied to develop the seawater chlorine decay model, such as first order decay model, EPA model, and two-phase model. The model simulation indicated that chlorine decay in seawater is influenced by both organic and inorganic matter in seawater. While inorganic matter has a negative correlation with the chlorine decay, organic matter has a positive correlation with the chlorine decay.

• 한국식품저장유통학회지
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• 제6권1호
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• pp.43-47
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• 1999

To develop a wrapping film, which suppresses the microbial decay through the storage and distribute of greenhouse fresh produce, the antimicrobial packaging films were made and applied to the preservation of grapes(Campbell early). For the purpose the films were made by adding 1% grapefruit seed extract(GFSE) to LDPE film(Control). Graps were separately wrapped with packaging films in the state of closely-adhered packaging as well as modified atmosphere packaging(MAP). The wrapped grapes were stored at 5$^{\circ}C$ for 65 days and then the colony count of contaminated microorganims, decay ration of grapes, the gas component within the packages and chemical qualities were investigated. The antimicrobial film packaging showed the efficient results to suppress microbial growth as compared with control. The total number of containated microorganisms were decreased gradually through all the storage period. In the closely-adhered packaging and MAP the decay ratios of grapes was 31% and 19%, indivisually. After the storage period of 65 days, the interior gas components of MAP were 4.5% of O2 and 17.6% of CO2, which were efficient for the storage of grapes. In addition, no negative effects in sweetness and acidities occurred.

• 한국식품영양과학회지
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• 제23권2호
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• pp.315-321
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• 1994

In order to prevent the postharvest decay and to promote the freshness retention of fruits and vegetables grapefruit seed extract(GFSE), natural microorganism control agent, was applied to the preservation of fresh fruits and vegetables. Freshfruits and vegetables treated with GFSE and stored in polyethylene film (0.1mm) at 1$0^{\circ}C$-15$^{\circ}C$ of natural low temperature low kept better qualities in color and texture than the GFSE -not- treated control. The treatment using GFSE ina 250ppm to 500ppm concentration seemed to be an effective one for the control of Botrytis cinerea isolated in red wine grapes. After 4 weeks of storage the firmness rate of cucumbers treated with the dilute GFSE was four times higher than that of non-treated ones. GFSE showed effective inhibitory action towards plant pathological bacteria and fungi which were involved in the decay of fruits and vegetables. Minimum inhibitory concentrations of GFSE towards them were in the range of 250ppm to 500ppm .Direct visualization of microbial cells and spores using electron microscopy showed microbial cells and fungal spores the function of which was destroyed by treating with the dilute solutions of GFSE. It was observed that GFSE would reduced disease damages and have bactericide & fungicide properties during the storage of such fruits and vegetables as egg plant, wild edible greens , kumquat, and kiwi fruit.

• 한국식품저장유통학회지
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• 제5권1호
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• pp.13-21
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• 1998

Korean medicinal herb extracts(KMHE) were applied to the preservation of greenhouse produce in order to prove their effectiveness. KMHE showed remarkable antimicrobial effects against Bacillus cereus, Peudomonas syringae, and Corynebacterium xerosis causing the postharvest decay of greenhouse produce. Among KMHE the extracts of Rheum palmatum L. and Coptis chinensis Franch most obviously inhibited the growth of microorganims causing the Postharvest decay of greenhouse produce, which destroyed to undetectable levels when treated with more than 500ppm of KMHE. The activities of KMHE were stable in the wide spectrum of pH and temperature. Direct visualization of microbial cells by using both transmission electron microscope and scanning electron microscope showed microbial cell membrane the function of which was destroyed by treating with the dilute solutions of KMHE. This change of cellular membrane permeability could be identified in the experiment that O-nitrophenyl-$\beta$-D-galactopyranoside(ONPG), the artificial substrate of $\beta$-galactosidase, was hydrolyzed in the presence of KMHE, indicating that the membrane was perturbed by KMHE.

• 한국식품저장유통학회:학술대회논문집
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• 한국식품저장유통학회 2003년도 제23차 추계총회 및 국제학술심포지움
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• pp.187-187
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• 2003

To examine the effect of packaging method on strawberry, tomato, and plum quality, the rate of weight loss, Hunter a value, decay rate, anthocyanin contents, and microbial (total bacterial counts, mold and yeast, and pseudomonas) changes were determined during storage. Strawberry was packaged with low density polyethylene (LDPE). Tomato and plum were packaged with high density polyethylene film (HDPE). Strawberries, tomatoes, and plums were then stored at 4$^{\circ}C$ and 20$^{\circ}C$, respectively. LDPE package was the most effective on the decrease of decay rate of strawberry and the rate of weight loss for packaged strawberry was lower than that of the non-packaged. HDPE package was the most effective on the rate of weight loss during storage of tomatoes and plums regardless of storage temperature. Hunter a value increased during storage. Anthocyanin contents of plums increased overall with increasing storage time, and plums stored without package were changed more than those with package. Microbial changes of strawberry, tomato, and plum stored at 4$^{\circ}C$ and 20$^{\circ}C$ were monitored during storage. Packaging method did not affect the microbial change, yet temperature did affect the microbial change significantly. These results indicate that storage of these commodities at 4$^{\circ}C$ should be recommended in terms ,of microbial safety as well as quality and shelf-life.

• 한국식품저장유통학회지
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• 제11권1호
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• pp.7-11
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• 2004

저장조건이 딸기 “미녀봉”의 저장 중 품질 및 미생물학적 변화에 미치는 영향을 연구하기 위하여 저장 중 중량감소율, 부패율, pH 및 적정산도, 총균수 및 곰팡이와 효모 수의 변화가 측정되었다. 딸기 시료는 LDPE로 포장하여 4$^{\circ}C$와 2$0^{\circ}C$에서 각각 저장하였다. LDPE포장은 대조구에 비해 중량감소율 및 부패율을 감소시켰다. 또한 포장방법은 저장중 미생물학적 변화에 영향을 끼쳤는데 저장온도와 상관없이 대조구와 비교해서 효모와 곰팡이뿐만 아니라 총균수의 감소를 야기시켰다. 본 연구결과는 딸기 “미녀봉”의 유통기한을 고려할 때 4$^{\circ}C$에서 LDPE 포장으로 저장하는 것이 바람직하다는 것을 나타냈다.

• 한국문화재보존과학회:학술대회논문집
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• 한국문화재보존과학회 2001년도 제14회 발표논문집
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• pp.27-34
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• 2001

화재를 예방하고자 방염 처리 한 일부 고건축재에서 발견된 미생물에 의한 고목재의 분해를 전자현미경을 사용하여 관찰하였다. 방염 처리한 고건축 부재는 2차벽 중층에 마이크로배열 방향과 동일한 동공을 가지고 있는 전형적인 연부후를 보였다. 또한 주사형 및 투과형 전자현미경을 사용하여 관찰한 결과 일부 세포벽은 세균에 의해 분해된 것으로 나타났다. 방염 처리한 고건축재에서 나타난 이같은 부후형태는 수분으로 포화된 수침 고목재에서 나타나는 전형적인 부후 형태이다. 부후 형태로부터 본 연구에 사용된 고건축 부재는 방염 처리 후 흡수성이 급격히 증가하였으며, 이같은 함수율의 증가는 사용된 방염제 때문인 것으로 생각된다. 본 연구 결과 사찰 및 궁질 등 고건축물에 사용하고 있는 방염제에 대한 보다 더 체계적이고 심도있는 연구가 필요함을 보여주었으며 아울러 방염제가 목재의 흡수성과 강도에 미치는 영향에 대한 연구가 뒤따라야함을 제시하였다. 본 논문은 또한 기상 열화에 의한 일부 목재의 표층부에 나타난 중간층의 분해에 대해서도 논의하였다.