• Restorative Dentistry and Endodontics
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• v.10 no.1
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• pp.55-62
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• 1984

This experimental study was made to evaluate the efficacy of root canal preparation of engine reamer versus hand reamer. Eighty extracted human teeth were prepared with the following treatments and devided into 4 groups; Group 1: Canal preparation with hand reamer, and irrigation with normal saline solution. Group 2: Canal preparation with engine reamer, and irrigation with normal saline solution. Group 3: Canal preparation with hand reamer, and irrigation with 3% hydrogen peroxide and 3.5% sodium hypochlorite solution. Group 4: Canal preparation with engine reamer, and irrigation with 3% hydrogen peroxide and irrigation with 3% hydrogen peroxide and 3.5% sodium hypochlorite solution. After decalcification, 5p. sections at levels 1-, 3-, and 5-mm from the apex were evaluated microscopically. The results were as follows; The effectiveness of hand reamer and engine reamer were equal in preparing the root canal at all levels from the apex, and were equal in normal saline solution groups, and 3% $H_2O_2$ and 3.5% NaOCl solution groups. Both in hand reaming groups and in engine reaming groups, some canal walls had still untouched portion, and canal irregularities and debris were still remained.

• Journal of fish pathology
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• v.13 no.2
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• pp.97-102
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• 2000

In order to investigate the effect of chlorine disinfectant against white spot baculovirus (WSBV), 5, 10, or 30 ppm of sodium hypochlorite (NaOCl) was treated to the WSBV-infected shrimp, Penaeus chinensis. In contrast with the non-treated control, no shrimp was dead after of sodium hypochlorite treatment. This result indicated that WSBV was inactivated by chlorine treatment. No inactivation of WSBV was observed by 10, 20, 30 ppm of povidon-iodine treatment. WSBV was also inactivated by 2, 4 hr sunlight exposure and by 1, 2, 3 hr drying. WSBV was inactivated very effectively by addition of fresh water on sea water.

• Restorative Dentistry and Endodontics
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• v.7 no.1
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• pp.65-69
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• 1981

This study was conducted to evaluate the cleansing effect of RC-Prep (10% Urea-peroxide, 15% EDTA) on apical third of root canal. Thirty single rooted human teeth were divided into three groups, and ten canals in each group were all enlarged three sizes greater than their original diameter with K-type files and irrigated with each of three irrigants. The three used irrigants were RC-prep (Premier Co.) in combination with 3.5% Sodium hypochlorite, Normal saline, 3.5% Na OCL. In each group, one of three irrigants were used in conjunction with instrumentation as they would be during clinical condition. After final irrigation, the canals were dried with paper points and the teeth were split longitudinally. The cleanness of canal walls iii the apical region were examined with Scanning Electron Microscope. The following results were drawn. 1. The use of Rc-Prep in combination with 3.5% NaOCl showed more clean canal surface than the use of other two irrigants. 2. The canals used RC-Prep in combination with 3.5% NaOCl revealed remnants of pulp tissue and smeared layer, but the openings of dentinal tubules were relatively clean and wide. 3. There was no significant difference in the debridement effect of 3.5% NaOCl and Saline solution. 4. The use of Saline solution showed great amount of remnants of pulp tissue which couldn't find in the use of 3.5% NaOCl.

• Restorative Dentistry and Endodontics
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• v.6 no.1
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• pp.51-62
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• 1980

A Scanning Electron Microscope study was conducted to compare the effectiveness of mechanical preparation of the root canal in conjunction with a few number of canal irrigants that have been widely used for canal treatment. The irrigants used in this study were 5% sodium hypochlorite, 3% hydrogen peroxide, 15% EDTA, and 30% hydrochloric acid. The root canals of 84 freshly extracted teeth with single or multi root were conventionally prepared with Hedstroem files. 78 canals were irrigated with normal saline solution following each instrument number and 6 canals were prepared without irrigation. After instrumentation 72 canals were flushed with various irrigants for predetermined length of time as shown on the Table 1. Additional 20 teeth were kept uninstrumented and five of them were immersed in 15% EDTA for 5 minutes, five in 5% sodium hypochlorite for 5 minutes, five in 3% hydrogen peroxide for 20 minutes, and the last five were only rinsed with saline solution. The SEM examination revealed as follows: 1. The canal wall cannot be thoroughly prepared by means of files. 2. No typical structural changes occured on instrumented dentin surface by saline solution, 3% $H_2O_2$, 5% NaOCl, within 5 minutes. 3. 5% NaOCl Solution showed excellent solvent effect to organic substances in uninstrumented canal within 5 minutes and 15% EDTA and 3% $H_2O_2$ showed unsignificant changes. 4. 15% EDTA and 30% HCl dissolved calcified debris and dentin chips that obturated the dentinal tubules and showed patent orifices. 5. 15% EDTA affected on peritubular dentin more readily and showed concavity around dentinal tubules.

• Membrane Journal
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• v.30 no.2
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• pp.138-148
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• 2020

The purpose of this study was to identify the cleaning efficiency of fouled multi-bore hollow fiber membranes after purification of contaminated water. The PSf (polysulfone) based hollow fiber membrane manufactured by Pure & B Tech Co., Ltd. Was used in this study. The antifouling characteristics during the water treatment were studied using bovine serum albumin (BSA) as a model compound and the chemical resistance was evaluated after long-term impregnation in sodium hypochlorite (NaOCl) solution and Citric acid to understand the long term stability of the membranes. Water permeability and mechanical strength of the membranes after prolonged chemical exposure was measured to observe the change in mechanical stability and long term performance of the membrane. moreover, the recovery efficiency was also evaluated after chemical enhanced backwashing of a membrane contaminated with bovine serum albumin. The PSf hollow fiber membrane exhibited excellent chemical resistance, and it was confirmed that the efficiency of sodium hypochlorite was high as a result of chemical enhanced backwashing.

• Journal of Dairy Science and Biotechnology
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• v.41 no.4
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• pp.203-210
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• 2023

Bacterial contamination negatively affects the quality, functionality, and safety of dairy products. Adherent populations of bacteria, referred to as biofilms, grow on the surfaces of dairy processing equipment and are the primary cause of dairy contamination. In addition, microorganisms present in the farm environment and dairy factory can contaminate the Clear-In-Place (CIP) line through raw milk transport pipes; therefore, exhaustive management is required. In dairy manufacturing facilities, biofilm formation is controlled using CIP systems that primarily require sodium hydroxide and nitric acid. However, the leakage or incomplete removal of these potently active compounds can be harmful to humans. In the present study, we compared the eradication of Escherichia coli and other bacteria using commercially available combinations of sodium hypochlorite (NaClO) and citric acid, which are recognized by the Korean Ministry of Food and Drug Safety (MFDS) as food disinfectants. When considered in the CIP system of the field manufacturing process, E. coli was not detected (compared to detection before treatment), and other bacteria were detected at 0-32 culture-forming units (CFU)/cm². The residual amount of chlorine ions after CIP treatment was similar to that in tap water, and there was no significant difference in the overall components of the fermented dairy products. Therefore, the NaClO/citric acid CIP system can be safely applied in dairy manufacturing processes.

• Restorative Dentistry and Endodontics
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• v.49 no.3
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• pp.25.1-25.9
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• 2024

Objectives: This study aimed to evaluate the color stability and solubility of Biodentine and NeoPutty in contact with different irrigation solutions. Materials and Methods: Biodentine and NeoPutty were set in cylindrical molds with 7 mm diameter and 1.5 mm high and immersed in distilled water, 17% ethylenediaminetetraacetic acid (EDTA), 2% chlorhexidine (CHX), 9% 1-hydroxyethylidene 1,1-diphosphonate (HEDP), and 5% sodium hypochlorite (NaOCl) solutions for 24 hours. The color change was measured with a spectrophotometer. The solubility values were calculated as the mass loss was expressed as a percentage of the original mass using an analytical balance with 10^-4 g accuracy. Data were analyzed with Kruskal-Wallis followed by Mann-Whitney U tests, and 2-way analysis of variance test followed by Bonferroni corrections for pairwise comparisons for solubility and color stability with a 5% significance threshold, respectively. Results: Biodentine exhibited higher color changes compared to the NeoPutty contact with all solutions except distilled water (p < 0.05). Both hydraulic cements (HCs) showed higher discoloration values immersion in CHX followed by NaOCl. No statistically significant difference was found between Biodentine and NeoPutty regardless of irrigation solution in terms of solubility (p > 0.05). Solubility values were lower in the distilled water group compared to EDTA and CHX (p < 0.05). Conclusions: Tested HCs showed solubility and color changes at various rates. NeoPutty could be an appropriate material in aesthetic areas. The usage of HEDP as an irrigant solution can be considered suitable for various endodontic treatments due to its relatively lower solubility and discoloration values.

• Asian Journal of Turfgrass Science
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• v.19 no.2
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• pp.115-123
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• 2005

The effect of sodium hypochlorite treatment on the germination of cattail (Typha spp.) seeds was investigated in growth chambers maintained on a 14-h photoperiod with various temperatures and light intensities. Germination rates of seeds were, in general, enhanced by the increase of light intensity and temperature regardless of cattail species. Seeds of T. oreientalis had 4.3, 13.0 and $7.3\%$ germination at temperatures of 20, 25 and $30^{circ}$C, respectively, under light intensity of 7.5${\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$. T. angustata showed higher germination rate, thus, 10.7, 22.7 and $50.7\%$ under same temperature and light environment. Under high light intensity of 79.5${\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$, the germination rates of T. oreintalis and T angustata were $78.3\%$ and $88.7\%$ at $30^{circ}$C, respectively. Scarification of seeds with NaOC1 ($4\%$, available chlorine) increased germination rate in both species, especially even at low temperature of $20^{circ}$C. Germination speed was also enhanced by NaOC1 treatment. High light intensity further increased the germination rate. When NaOC1 treated seeds were sowed on the soil surface in plastic house, the seedling emergence was nearly $100\%$. Untreated seeds of T. oreintalis and T. angustara showed 40 and $50\%$, respectively, in germination under same condition. However, when the depth of soil covering was over 1.0 cm, seedling emergence was retarded more than 1 month. On the process of seedling development, emergence of mesocoty1 occurred firstly and after than primary root and first leaf were developed on the end of elongated mesocotyl. These results suggest that the promotion of seed germination by NaOC1 pretreament may be induced from the increase of light absorptivity as well as water permeability through scarifying and bleaching the seed coat.

• Journal of Life Science
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• v.7 no.3
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• pp.212-218
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• 1997

The studies were conducted to explore the dffects of growth or survival against various factors and plasmid profiles of 49 Y. enterocolitica isolated from springs water. In the presence of calcium hypochlorite, y. enterocolitica was entirely extinguished by exposure for 33 hours at 0.8 ppm concentration, and was grown up to 7% NaCl, but not at 95 NaCI. Y. enterocolitica was presented optimal growth at pH 7.0 anad 9.0, and not allowth the growth at pH3.0, 5.0 and 11.0. The optimal temperature for growth of Y. enterocolitica was 25$\circ$C and 35$\circ$C, and allowed the growth at refrigerant temperature, 5$\circ$C. Y. enterocolitica was remarkably decreased by exposure for 30 seconds under UV light, and entirely extinguished by exposure for 90 seconds. Therefore, UV light was effective for sterilization of Y. enterocolitica. Fourty-nine strains of Y. enterocolitica were harbor plasmid DNA of approximately 46 Kb molecular weight.

• Journal of Plant Biotechnology
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• v.40 no.1
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• pp.43-48
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• 2013

Oreorchis coreana Finet is threatened globally by over-collection from its natural habitats for horticultural purposes. Its rarity in nature makes this plant one of the most endangered species in Korea. In this study, we investigated the effects of sodium hypochlorite (NaOCl) on orchid seed viability and seed germination. An in vitro bioassay swelling test using immature seeds was compared with a standard chemical procedure using triphenyl tetrazolium chloride (TTC) to test seed viability. In general, the bioassay was more appropriate for estimating embryo viability after a prolonged pre-treatment (more than 1 h) in 1% NaOCl, a surface sterilant often used to enhance germination of seeds of terrestrial plants. Therefore, an efficient method for investigating in vitro swelling of immature seeds is urgently needed. We established a method for determining the viability and swelling of O. coreana seeds via in vitro examination of immature seeds. Treatment of immature seeds with 1% NaOCl for 10 min greatly enhanced the extent of swelling of immature zygote embryos when compared to untreated seeds. These data obtained here appear to be comparable to viability and swelling that occurs in O. coreana seeds via asymbiotic germination.