• 한국미생물·생명공학회지
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• 제35권4호
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• pp.334-338
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• 2007

유기 염소계 소독제인 삼염화이소시아눌산(trichloroisocyanuric acid)에 의한 다양한 미생물의 사멸특성을 규명하기 위하여, 대장균, 고초균, 포도상구균, 레지오넬라균, 수도모나스균 등을 각각 증류수에 부유시킨 후, 접촉시간과 소독제의 농도를 변화시키면서 사멸률을 측정하였다. 삼염화이소시아눌산 8 ppm 수용액 하에서 미생물 99%의 사멸률에 도달하는 시간은 대장균 60초, 수도모나스균 368초, 포도상구균 372초, 고초균 506초, 레지오넬라균 812초 순으로 측정되었다. 특히 대장균 사멸률 99%에 도달하기 위한 같은 농도(8 ppm) 세 종류의 소독제 접촉시간은 삼염화이소시아눌산 60초, 단토브롬(BCDMH, Bromochlorodimethylhydantoin) 114초, 칼슘하이포(calcium hypochlorite) 7,100초 순으로, 대장균에 대한 삼염화이소시아눌산의 소독력이 가장 우수하게 측정되었다. 본 연구결과는 염소계 소독제에 의한 사멸특성이 미생물 종 특이적이며 또한 소독제의 종류, 농도, 접촉시간에 따라서 매우 다양하게 측정됨을 제시하고있다.

• 한국환경보건학회지
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• 제39권4호
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• pp.376-382
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• 2013

Objectives: The objectives of this study were to identify the virucidal efficacy against the viral hemorrhagic septicemia virus (VHSV) of an aquatic disinfectant tablet composed of calcium hypochlorite. Methods: Virucidal efficacy was determined through the viability of VHSV contacted with the disinfectant in a viral stock cultured in a fathead minnow cell line. An aquatic disinfectant tablet and VHSV were reacted under distilled water (DW), hard water (HW) or organic matter suspension (OM) conditions. Results: Under DW and HW conditions, VHSV was inactivated with 24,000- and 2000-fold dilutions of the aquatic disinfectant tablet, respectively. With the investigation of the antiviral effect of the disinfectant under OM conditions, VHSV was inactivated with a 16,000-fold dilution of the aquatic disinfectant tablet. Conclusions: The results from this study showed that the aquatic disinfectant tablet was a highly effective disinfectant against VHSV. In the future, a controlled field trial is required to determine whether the use of an aquatic disinfectant tablet will be able to reduce VHSV in a cultured marine fish farm.

• 한국작물학회지
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• 제40권4호
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• pp.487-493
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• 1995

본 실험은 콩나물 재배과정 중에 일어나는 부패문제를 해결하기 위하여 사용이 허가된 산성 식품 첨가제들을 대상으로 그 이용 가능성을 찾아보고자 수행되었다. 다소 노화된 은하콩을 재료로 콩나물 배축의 부패에 관여하는 균(부패균)을 순수 분리하여 그 특성을 조사하였고, propionic acid 등 8가지 약제처리가 부패균의 증식 억제효과를 인왕배지상에서 검토하였다. 또한 1% 이하의 약액처리가 콩나물 발아와 유묘생장에 미치는 영향을 조사하여 약해유발의 가능성도 검토하였으며 그 결과들을 요약하면 다음과 같다. 1. 부패균으로 확인된 3종류의 균계를 대상으로 Gram stain등 8가지 미생물학적 검정을 통하여 분석한 결과 상호 약간의 특성 차이는 있었으나 Pseudomonas속의 균계로 판단되었으며, 분리된 곰팡이류 중에는 부패균이 없었다. 2. 5% 이상의 농도에서는 공시약제 중 sodium hypochlorite의 부패균 증식억제 효과가 가장 컸으나 발아를 극심하게 저해하여 실용성이 없다고 판단되었다. 3. Propionic acid, acetic acid, calcium propionate, sodium propionate등의 약제 효과가 큰 것으로 나타났는데 propionic acid와 acetic acid의 효과가 상대적으로 더 뚜렷하였다. 4. Propionic acid, acetic acd, calcium propionate, sodium propionate 등의 선발된 4가지 약제는 1.0% 및 그 이하의 농도에서도 다소의 부패균 증식억제 효과가 나타나 부패경감제로서의 충분한 이용 가능성을 보였다. 5. 1%이하의 용액에 콩종자를 침지처리 하였을 때 무처리에 비해 선발된 4가지 약제처리에서 모두 발아율, 초기생육 및 비정상발아 개체율에서 차이를 나타내지 않아 약해는 문제시 되지 않을 것으로 판단되었다.

• 한국식품위생안전성학회지
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• 제27권3호
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• pp.290-294
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• 2012

Vibrio spp. and Streptococcus spp. have caused a considerable disease of farmed fish and economic loss in fish farming and seafood industry. In this study, the efficacy of an aquatic disinfectant tablet composed to calcium hypochlorite was evaluated against V. anguillarum and S. iniae. A bactericidal efficacy test by broth dilution method was used to determine the lowest effective dilution of the disinfectant following exposure to test bacteria for 30 min at $4^{\circ}C$. An aquatic disinfectant tablet and test bacteria were diluted with distilled water (DW), hard water (HW) or organic matter suspension (OM) according to treatment condition. V. anguillarum on the DW, HW and OM condition was completely inactivated with 16,000 15,000 and 13,000 fold dilutions of the disinfectant, respectively. On the DW, HW and OM condition, S. iniae was absolutely inactivated with 17,000 16,000 and 14,000 fold dilutions of the disinfectant, respectively. As an aquatic disinfectant tablet possesses bactericidal efficacy against fish pathogenic bacteria such as V. anguillarum and S. iniae this disinfectant solution can be used to control the spread of fish infective bacterial diseases.

• 펄프종이기술
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• 제32권3호
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• pp.65-74
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• 2000

This study was carried out to acquire basic data necessary for the use of rice-straw chemical pulp. It investigated the proper bleaching conditions when rice-straw chemical pulps(alkaline sulfite-Na2S2O4 pulp) were bleached with the various kinds of bleaching agents. And physical properties of bleached pulps were tested. The results of this study were as follows; 1, The proper conditions of chlorine sequence were determined to be 4% concentration of chlorine 25$^{\circ}C$ of reaction temperature and 50 minutes of reaction time. 2. For calcium hypochlorite sequence the proper conditions of chemical concentration reac-tion temperature and reaction time were 3% 25$^{\circ}C$ and 20 minutes respectively. 3. For chlorine dioxide sequence the proper conditions were 1% concentration of chlorine dioxide 70$^{\circ}C$ of reaction temperature and 2hr. of reaction time. 4. The proper conditions of hydrogen peroxide sequence were 1.5% concentration of hydro-gen peroxide 70$^{\circ}C$ of reaction temperature and 1hr. of reaction time respectively. 5. When the rice-straw chemical pulp were bleached with four kinds of bleaching agents methioned above in the proper conditions respectively brightnesses were the order of chlorine dioxide calcium hypochlorite, chlorine, hydrogen peroxide. And strengthes of pulps bleached with chlorine dioxide and hydrogen peroxide were higher than those of pulps bleached with other bleaching agents.

• Restorative Dentistry and Endodontics
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• 제40권3호
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• pp.216-222
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• 2015

Objectives: To evaluate the effects of copolymer of acrylic acid and maleic acid (Poly[AA-co-MA]) and calcium hypochlorite ($Ca(OCl)_2$) on root canal dentin using scanning electron microscope (SEM). Materials and Methods: Twenty-four single-rooted teeth were instrumented and the apical and coronal thirds of each root were removed, leaving the 5 mm middle thirds, which were then separated into two pieces longitudinally. The specimens were randomly divided into six groups and subjected to each irrigant for 5 min as follows: G1, $Ca(OCl)_2$; G2, Poly(AA-co-MA); G3, $Ca(OCl)_2$ + Poly(AA-co-MA); G4, sodium hypochlorite (NaOCl); G5, ethylenediaminetetraacetic acid (EDTA); G6, NaOCl+EDTA. The specimens were prepared for SEM evaluation. Smear layer, debris and erosion scores were recorded by two blinded examiners. One image from G3 was analyzed with energy dispersive spectroscopy (EDS) on suspicion of precipitate formation. Data were analyzed using the Kruskal-Wallis and Dunn tests. Results: G1 and G4 showed the presence of debris and smear layer and they were statistically different from G2, G3, G5 and G6 where debris and smear layer were totally removed (p < 0.05). In G1 and G4, erosion evaluation could not be done because of debris and smear layer. G2, G3 and G5 showed no erosion, and there was no significant difference between them. G6 showed severe erosion and was statistically different from G2, G3 and G5 (p < 0.05). EDS microanalysis showed the presence of Na, P, and Ca elements on the surface. Conclusions: Poly(AA-co-MA) is effective in removing the smear layer and debris without causing erosion either alone or with $Ca(OCl)_2$.

• Restorative Dentistry and Endodontics
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• 제40권1호
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• pp.44-49
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• 2015

Objectives: This study compared the ability of several techniques to remove calcium hydroxide (CH) from the root canal and determined the influence of CH residues on the accuracy of the electronic apex locator. Materials and Methods: Root canals of 90 human maxillary lateral incisors with confirmed true working length (TWL) were prepared and filled with CH. The teeth were randomly assigned to one of the experimental groups according to the CH removal technique (n = 14): 0.9% saline; 0.9% saline + master apical file (MAF); 17% ethylenediamine tetraacetic acid (EDTA); 17% EDTA + MAF; 5.25% sodium hypochlorite (NaOCl); 5.25% NaOCl + MAF. Six teeth were used as negative control. After CH removal, the electronic working length was measured using Root-ZX (Morita Corp.) and compared with TWL to evaluate Root-ZX accuracy. All specimens were sectioned longitudinally, and the area of remaining CH (CH) and total canal area were measured using imaging software. Results: The EDTA + MAF and NaOCl + MAF groups showed better CH removal than other groups (p < 0.05). Root-ZX reliability to prevent overestimated working length to be > 85% within a tolerance of ${\pm}1.0mm$ (p < 0.05). There was strong negative correlation between amount of CH residues and EAL accuracy (r = -0.800 for ${\pm}0.5mm$; r = -0.940 for ${\pm}1.0mm$). Conclusions: The mechanical instrumentation improves the CH removal of irrigation solutions although none of the techniques removed the dressing completely. Residues of CH medication in root canals affected the accuracy of Root-ZX adversely.

• Restorative Dentistry and Endodontics
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• 제23권1호
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• pp.379-390
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• 1998

In endodontic treatment, calcium hydroxide has been used as intracanal medicament. Although calcium hydroxide should be removed thoroughly before permanent root canal filling, no effective method for its removal has been reported. Because of irregularity of root canal walls, root curvatures and anatomic variations, it is insufficient to remove calcium hydroxide from the canal wall only by mechanical instrumentation Considering the chemical effects of irrigants on calcium hydroxide, $Ca^{++}$ dissolving effect from two calcium hydroxide products is investigated, using dis- tilled water, NaOCl, citric acid and EDTA. Vitapex$^{(R)}$ 0.1g and calcium hydroxide 0.03g were dissolved in distilled water, 5% NaOCl, 50% citric acid and 17% EDTA respectively, at 1, 3, 5, 10min. time interval. The solution was filtered using filter paper(pore size $5{\mu}m$) and $Ca^{++}$ concentration was determined by ion chromatography. The result were as follows : 1. Distilled water, NaOCl, citric acid and EDTA abstracted more $Ca^{++}$ from calcium hydroxide than Vitapex$^{(R)}$ except NaOCl 1, 5, 10 time interval. 2. EDTA and citric acid abstracted more $Ca^{++}$ from Vitapex$^{(R)}$ and calcium hydroxide than distilled water or NaOCl. The overall result support the view that water-based calcium hydroxide product is easily removed than oil-based calcium hydroxide product and EDTA, citric acid are more effective in $Ca^{++}$ elution than NaOCl or distilled water.

• 한국식품위생안전성학회지
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• 제28권3호
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• pp.227-233
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• 2013

신선편의 샐러드와 유기농 채소에 오염되어 있는 식중독균인 B. cereus, S. aureus 그리고 E. coli를 대상으로 살균소독제와 유기산에 대한 감수성을 평가하여 신선편의 식품의 미생물학적 안전성의 확보를 위한 올바른 세척제와 사용량을 제시하고자 하였다. S. aureus는 2% acetic acid, malic acid, tartaric acid와 1% CaO에 대하여 고농도의 염소계, 과산화수소계 보다 높은 살균 효과를 보였고 E. coli의 경우에는 1% acetic acid와 CaO처리에 의해 80%의 분리주가 감소하여 50% 에탄올과 400 ppm 차아염소산나트륨과 대등한 감소율을 보였다. B. cereus 분리주에 대한 1% CaO, 0.5% acetic acid, 2% malic acid와 tartaric acid 처리는 200 ppm의 차아염소산나트륨보다 높은 감소율을 나타내었고, 1%의 과산화수소와 대등한 감소율을 나타내었다. 본 연구에 따라 천연 물질 유래 살균 소독제인 CaO와 유기산은 기존의 화학적 살균제를 대체할 수 있는 천연 살균 소독제로 활용될 수 있을 것이고 특히 환경 친화적이고 안전한 유기산은 고품질의 신선편의 채소를 안전성으로 공급하는데 효과적인 것으로 판단되었다.

• Bulletin of the Korean Chemical Society
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• 제25권8호
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• pp.1251-1252
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• 2004