• Korean Journal of Food Science and Technology
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• v.41 no.5
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• pp.578-586
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• 2009

This study was conducted to determine the effects of alkaline electrolyzed water (AIEW), acidic electrolyzed water (AcEW), 1% citric acid, and 100 ppm sodium hypochlorite, either alone or in combination with citric acid, in reducing the populations of spoilage bacteria and foodborne pathogens (Listeria monocytogenes and Escherichia coli O157:H7) on lettuce at various exposure times (3, 5, and 10 min) with different dipping temperatures (1, 20, 40, and $50^{\circ}C$). In addition, the inhibitory effect of alkaline electrolyzed water combined with citric acid on the browning reaction during storage at $4^{\circ}C$ for 15 days was investigated. Compared to the untreated control, electrolyzed water more effectively reduced the number of total bacteria, mold, and yeast than 100 ppm sodium hypochlorite under the same treatment conditions. All treatments exposed for 5 min significantly reduced the numbers of total bacteria, yeast, and mold on head lettuce. The inactivation effect of each treatment on head lettuce was enhanced as the dipping temperature increased from 1 to $50^{\circ}C$, but there was no significantly difference at temperatures greater than $40^{\circ}C$ (p<0.05). The total counts of yeast and mold in head lettuce were completely eliminated when a combination of 1% citric acid and AlEW treatment was used at temperatures greater than $40^{\circ}C$. However, decreased reduction in L. monocytogenes (2.81 log CFU/g), and E. coli O157:H7 (2.93 log CFU/g) on head lettuce was observed under these treatment conditions. In addition, enhanced anti-browning effect was observed when the samples were subjected to both 1% citric acid and AlEW treatment at temperatures greater than $40^{\circ}C$ compared to when single treatments alone were used. Thus, this combined treatment might be considered a potentially beneficial sanitizing method for improving the quality and safety of head lettuce.

• Applied Chemistry for Engineering
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• v.18 no.2
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• pp.148-154
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• 2007

This study was performed to evaluate the application of $TiO_2$ on the photocatalytic treatment of swine wastewater. $TiO_2$ sol was prepared by hydrothermal method with the agent ratio($(C_2H_5)_2NH_2\;mol/Ti(OC_3H_7)_4\;mol)=1$ and R ratio ($H_2O\;mol/Ti(OC_3H_7)_4\;mol)=42$. The effect of parameter on the removal efficiency of swine wastewater in a batch type immobilized photocatalyst system such as initial pH, intensity of UV, dosage of $TiO_2$, air flow rate, and concentration of $H_2O_2$ was examined. Wastewater was effectively eliminated in the presence of both UV light illumination and $TiO_2$. Photocatalytic activity was higher in acidic condition compared to neutral and alkaline conditions. In addition, photocatalytic activity increased with increasing UV light intensity, dosage of $TiO_2$, the flow rate of air and the amount of $H_2O_2$ added as an oxidant, but the excess amount of $H_2O_2$ dosage decreased the removal efficiency.

• Korean Journal of Food Science and Technology
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• v.44 no.5
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• pp.628-633
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• 2012

This study investigated the washing efficiency of electrolyzed water for the removal of microorganisms and pesticide residues from Chinese cabbage. Initial total bacteria and coliform counts were 6.64 and 3.56 log cfu/g respectively. After washing, total bacteria count of tap water (TW) were 5.97 log cfu/g and low alkaline electrolyzed water (LAlEW) and strong acidic electrolyzed water (SAcEW) were 1.63-4.67 log cfu/g. Especially SAcEW-100 was found to the most effective method of washing the cabbages. After washing, the coliform count was dramatically reduced. The removal rate of pesticide residues by NaClO treatment (36.93-50.13%) was greater than that of TW treatment (32.28-38.46%). The removal rate of LAlEW-100 and SAcEW-100 was 63.79 and 78.30% respectively, and was higher than those of TW and NaClO treatments. The vitamin C content of the Chinese cabbages after all treatments did not differ significantly. Consequentially, the electrolyzed water was found to be effective to remove bacteria and pesticide residues from Chinese cabbage without affecting quality.

• Asian-Australasian Journal of Animal Sciences
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• v.30 no.2
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• pp.192-197
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• 2017

Objective: The study was conducted to evaluate the stability of commercial coated lipase (CT-LIP) in vitro. Methods: The capsules were tested under different conditions with a range of temperature, pH, dry heat treatment and steaming treatment, simulated gastric fluid (SGF) and simulated intestinal fluid (SIF) in this work, respectively. Free lipase (uncoated lipase, UC-LIP) was the control group. Lipase relative activities measured in various treatments were used as a reference frame to characterize the stability. Results: The lipase activities were decreased with increasing temperatures (p<0.05), and there was a markedly decline (p<0.01) in lipase comparative activities of UC-LIP at $80^{\circ}C$ compared with CT-LIP group. Higher relative activities of lipase were observed in CT-LIP group compared with the free one under acidic ambient (pH 3 to 7) and an alkaline medium (pH 8 to 12). Residual lipase activities of CT-LIP group were increased (p<0.05) by 5.67% and 35.60% in dry heat and hydrothermal treatments, respectively. The lipase relative activity profile of CT-LIP was raised at first and dropped subsequently (p<0.05) compared with constantly reduced tendency of UC-LIP exposed to both SGF and SIF. Conclusion: The results suggest that the CT-LIP possesses relatively higher stability in comparison with the UC-LIP in vitro. The CT-LIP could retain the potential property to provide sustained release of lipase and thus improved its bioavailability in the gastrointestinal tract.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.10 no.1
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• pp.17-22
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• 1977

In the present paper, the effect of sodium sulfite treatment on tile inhibition of browning reactions occurring in the storage of dried oyster was tested and the supplementary effect of antioxidantsaddedwasalsomentioned. Dried oysters treated with sodium sulfite solutions as described in the previous paper(Lee and Choi, 1977) were stored in the bottles with silica gel bags at room temperature with or without the application of antioxidants. The ethanol solution of an antioxidant mixture(BHA, BHT, plus, synergists) was sprayed on the surface of cooked oyster before drying. The density of brown pigment was determined spectrophotometrically by measuring the absorbance at 420 and 440 nm of both fractions of pigment extract, namely chloroform-methanol and water soluble fractions, which represent the brown color developed by fat oxidation and Maillard reactions respectively. TBA value was also measured for the oxidative rancidity in oysters during the storage. It appeared from the results that the 0.5 M sodium sulfite-60minute treated samples showed better effect after 150 day storage at room temperature. Controlling tile pH of treating solutions, did not reveal so much different in inhibitory effect in the aspect of color but a more reduction of tyrosine and reducing sugar was resulted with acidic solution than with alkaline solution. The development of brown color in dried oyster seemed to be leaded rather by the oxidative rancidity of lipids than sugar-amino reactions particularly in a long-term storage since the browning of chloroform-methanol fraction progressed more rapidly than of water. soluble fraction. The application of antioxidant, therefore, could largely retard the browning of the product as appeared in the results that sodium sulfite treated oyster with addition of antioxidant kept the best color during the storage.

• Applied Chemistry for Engineering
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• v.23 no.4
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• pp.399-404
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• 2012

The objective of this study was to investigate the efficient pretreatment method for bioethanol production from rice hull. Ammonia and sodium hydroxide as an alkaline solution and dilute sulfuric acid as an acidic solution were used in a batch reactor under high-temperature and high-pressure conditions. The highest enzymatic saccharification efficiency of 82.8% and ash removal rate of 94.7% were obtained in the dilute sulfuric acid treated sample after the sodium hydroxide solution treatment. The enzymatic saccharification efficiencies and ash removals of pretreated rice hull samples have very similar variation tendency. This means that the maximum obstructive factor for the enzymatic saccharification of rice hull is the ash (silicate) content in biomass. The findings suggest that the combined sodium hydroxide-dilute sulfuric acid treatment system under high-temperature and high-pressure conditions is a promising pretreatment method to enhance the enzymatic saccharification of the silica-rich biomass.

• Resources Recycling
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• v.8 no.1
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• pp.11-17
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• 1999

This study was carried out to investigate the efficiency of stcclmaldng slag and sludge in removing metals existing in wastewater or leachate. Laboratory experiments were performed as a function of initial concentration of metals. pH a and temperature of the background solution and the presence of che1ating agent, EDTA. The test conditions were temperatures r ranging from $25^{\circ}C$ to $50^{\circ}C$; initial concentrations varying from 5mg/L to 50 mg/L; pH between 3 and 11; and Cu. Cd‘ and Pb a as adsorbates. The results of tests showed that overall rates of metals removal were 20~30% at pH 3 and greater than 90% at p pH 7 and 11. Metals were removed from the solution predominantly via adsorption in acidic conditions, and the combined e effects of adsorption and precipitation in neutral and alkaline conditions. In view of the test results and other engineering c characteristics of steelmaking slag and sludg$\xi$, these industrial by-products from steel industry have a high potential to be used l in wastewater treatment and are particularly beneficial when used as landfill liner additives due to thelJ ability to remove heavy m metals from leachate.

• Resources Recycling
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• v.13 no.4
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• pp.23-31
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• 2004

Basic studies have been conducted regarding the attempt of the utilization of waste Undaria pinnatifida as an adsorbent for the adsorption treatment of lead-containing wastewater. Undaria pinnatifida was found to be chiefly composed of hyo-carbonaceous compounds and have a fairly high specific surface area, which suggesting the possibility of its application as a Potential adsorbent. The electrokinetic Potential of Undaria pinnatifida particles was observed to be negatively highest at around pH 8 and the fact that its electrokinetic potentials are negative at the whole pH range supported it might be an efficient adsorbent especially for cationic adsorbates. Under the experimental conditions, $Pb^{2+}$ was found to mostly adsorb onto Undaria pinnatifida within a few minutes and reach the equilibrium in adsorption within ca. 30 minutes. The adsorption of $Pb^{2+}$ was exothermic and explained well by e Freundlich model. Acidic pretreatment of Undaria pinnatifida enhanced its adsorption capacity for $Pb^{2+}$ , however, the reverse was observed for alkaline pretreatment. The formation of organometallic complex between $Pb^{2+}$ and some functional groups on the surface of Undaria pinnatifida was considered to be one of the main drives for adsorption. Finally the adsorbability of$ Pb^{2+}$ was examined to be rather affected by several solution features such as the coexistence of other adsorbate, the variation of ionic strength, and the concentration of complexing agent.

• Journal of Korea Foresty Energy
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• v.21 no.2
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• pp.25-33
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• 2002

One of the critical problems to preserve books and documents in libraries and archives is the deterioration. Some of previous results showed that the major cause of paper deterioration was the acid-catalyzed hydrolysis of the cellulose in paper fibres and aging rate of acidic paper was faster than that of alkaline paper. Therefore, It is necessary to remove the acid in the paper for reducing the rate of paper deterioration. It has been reported to extend the useful life of acidic paper by three to five times. Recently, It has been recognized the need for an effective method of deacidifying large quantities of books and document. However, in the previous many reports little attention was paid to the effect of paper additives. In this paper, We carried out experiment about the effect of additives on paper aging and the effect of deacidification by the gaseous ethanolamines (monoehtanolamine, diethanolamine, triehtanolamine). In result, it was found that the strength of aging was in the order of the alum＋rosin＞alum ＞AKD＞ control and the rate of deacidification was in the order of the monoethanolamine＞diethanolamine＞triethanolamine. The treatment with the gaseous ethanolamines caused decreasing of brightness and dropping of fold endurances. However, deacidification by combination treatment of the various gaseous ehtnaolamines prevented from decreasing of brightness and dropping of folding endurances.

• Korean Journal of Clinical Laboratory Science
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• v.47 no.4
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• pp.243-250
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• 2015

A bone marrow biopsy that has undergone decalcification with 10% nitric acid could not be used for various pathological tests and had extremely limited reproducibility. The fixing solution of each experimental group was differentiated in usage, one solution including acid and the other not. The use of the decalcification solution was separated into either acidic or alkaline (EDTA), and further experiments were conducted with differing time phases. When using a fixing solution and decalcification solution which included acid, the specimens were faulty to the extent that all pathological tests were impossible. However specimens that were processed with an EDTA type decalcification solution did not display a non-specific reaction in EBV ISH and were even able to produce results that were at a level suited to various studies or a pathological diagnosis in the FISH, DNA, RNA tests. By improving the fixing and decalcification of bone marrow biopsy, the study was able to make possible ISH, FISH, DNA tests as well as RNA study, and secured the sensitivity, specificity, and reproducibility of various test methods. The stabilization of various test methods that use bone marrow biopsy contributes to the diagnosis, prognosis, prediction, treatment of the patient and provide guidelines for decision-making.