• Journal of Life Science
• /
• v.28 no.8
• /
• pp.938-944
• /
• 2018

This study evaluated tyrosinase, elastase inhibitory, and antioxidant activities of fermented Rhododendron micranthum Turcz. extract using a lactic acid bacterium, Lactobacillus rhamnosus. The optimum conditions for fermentation of R. micranthum Turcz. extract were $37^{\circ}C$ and 3% R. micranthum Turcz. extract for 3 days based on the bacterial cell number, total phenolic compounds, DPPH radical scavenging activity, and tyrosinase and elastase inhibitory activity. After culture for 3 days using 3% R. micranthum Turcz. extract, the cell mass of L. rhamnosus reached $5.7{\times}10^9CFU/ml$. The results indicated that R. micranthum Turcz. extract can be used for industrial lactic acid bacteria culture. After fermentation under optimum conditions, the total content of phenolic compounds of the fermented R. micranthum Turcz. extract was 157 GAE mg/ml, and the $IC_{50s}$ of DPPH radical scavenging activity, ABTS radical scavenging activity, and tyrosinase and elastase inhibitory effects were 78.8, 79.8, 329.1, and $449.5{\mu}g/ml$, respectively. The fermented R. micranthum Turcz. extract exhibited 1.2-, 1.3-, 1.5-, 2.4-, and 5.6-fold higher total content of phenolic compounds, DPPH radical scavenging activity, ABTS radical scavenging activity, and tyrosinase and elastase inhibitory effects than the nonfermented R. micranthum Turcz. extract. These results indicated that fermented R. micranthum Turcz. extract using L. rhamnosus can be used for developing new natural functional ingredients for the health food or cosmetic industry.

• Food Science and Preservation
• /
• v.15 no.6
• /
• pp.915-921
• /
• 2008

This study was carried out to investigate the recognition, preference of mushrooms and mushroom processed foods among general consumers in order to develop new mushroom processed foods. The questionnaires are consists of general questions, health status, intake frequency of mushrooms, reason for prefer mushrooms, have purchased experience or not of mushroom processed foods and prefer mushroom processed foods to want development by age. A total 1173 questionnaires were analyzed for statistical analysis. The statistical analysis was completes using SPSS Win program (Version 14.0) for descriptive analysis and $X^2$-test. Main results of this study were as follow: Most of respondents prefer mushrooms and 28.5% of the respondents like Pleurotus eryngii most. The most reasons for the prefer mushrooms are freshness. The frequency of intake mushrooms was 6-8 times per months. The most consideration factor in purchasing mushrooms was freshness/hygiene. 55.6% of the respondents had purchasing experience of mushroom processed foods to eat. The most purchased mushroom processed foods were soup and hor cereal. The most consideration factor in purchasing mushroom processed foods was improvement of taste.

• Korean Journal of Food Science and Technology
• /
• v.46 no.1
• /
• pp.94-99
• /
• 2014

The present study aimed to evaluate the in vitro antimycobacterial effects of hop plant, Humulus japonicus. Methanol extract of H. japonicus (MeOH extract) showed strong direct bactericidal effects against Mycobacterium tuberculosis in vitro. Furthermore, the MeOH extract significantly inhibited M. tuberculosis growth in human macrophages. When five fractions obtained from MeOH extract were examined using the same methods, the hexane and ethyl acetate fractions showed bactericidal effects against M. tuberculosis in vitro, whereas the butanol and water fractions inhibited M. tuberculosis growth in macrophages. Because H. japonicus extract exhibited antimycobacterial activity against both free M. tuberculosis in culture medium and intracellular M. tuberculosis in human macrophages, this plant might be a good candidate for development of a new anti-tuberculosis drug.

• Journal of Korea Technology Innovation Society
• /
• v.20 no.1
• /
• pp.153-174
• /
• 2017

This study tried to suggest South-North Korea's S&T cooperative strategies and priority areas using mixed-methodology. First, survey research was conducted to analyze the understanding of scientists how they think about these issues. We surveyed scientists whose names are on the KOFST mailing list and analyzed 485 questionnaire responses. After that, experts who are participating in FGI discussed more deeply about the survey results and suggested the feasible strategies and projects. The results suggest some findings about priority cooperation area, new projects and strategies. Priority areas of S&T cooperation are following; agriculture, electricity & energy, and health care. However, more important thing than these priority areas is how to approach the inter-Korean S&T cooperation. More strategic approach is needed while promoting exchange and cooperation projects with north-korea. Also more long-term approach is needed to maintain the sustainability of this S&T cooperation.

• Journal of the Korean Applied Science and Technology
• /
• v.37 no.2
• /
• pp.374-384
• /
• 2020

This study was carried out to investigate the food value of Dae Hong(Prunus mume Siebold et Zucc), and also to analyzed contents of general component, free sugar, organic acid, amino acid, mineral element, and vitamins. The carbohydrate of Dae Hog showed the highest content of 46.8±0.92%, followed by crude protein(18.9±0.01%), moisture content(11.8±0.13%), and crude fiber, crude fat, ash(5.7±0.94~6.7±0.52%). In case of free sugar contents, 5 types were found. Most of them were mannitol and fructose. 6 mineral contents were also found, too; K and P showed the highest level. The total phenol content was 615.99±0.52 mg/100 g. Including seven different type of essential amino acids, the total amino acid content of Dae Hong was 121.42 mg/g. These results point out the potential of Dae Hong as innovative food for health or to be incorporated in new products as natural food preservatives and supplements.

• Journal of Digital Convergence
• /
• v.11 no.4
• /
• pp.221-227
• /
• 2013

RFID is an automatic identification technology that can control a range of information via IC chips and radio communication. Also known as electronic tags, smart tags or electronic labels, RFID technology enables embedding the overall process from production to sales in an ultra-small IC chip and tracking down such information using radio frequencies. Currently, RFID-based application and development is in progress in such fields as health care, national defense, logistics and security. RFID structure consists of a reader that reads tag information, a tag that provides information and the database that manages data. Yet, the wireless section between the reader and the tag is vulnerable to security issues. To sort out the vulnerability, studies on security protocols have been conducted actively. However, due to difficulties in implementation, most suggestions are concerned with theorem proving, which is prone to vulnerability found by other investigators later on, ending up in many troubles with applicability in practice. To experimentally test the security of the protocol proposed here, the formal verification tool, CasperFDR was used. To sum up, the proposed protocol was found to be secure against diverse attacks. That is, the proposed protocol meets the safety standard against new types of attacks and ensures security when applied to real tags in the future.

• Clean Technology
• /
• v.23 no.3
• /
• pp.302-307
• /
• 2017

This study was conducted to evaluate the feasibility of in situ soil flushing for TPH-contaminated soil remediation with column test. The soil texture of the soil was sand and the initial TPH concentration was $9,369mg\; kg^{-1}$. 0.1% Tween-80 was selected as surfactant solution. And the acrylic and the glass syringe columns were used as reactors. In the acrylic column test, 35% of the initial TPH was removed in 1 PV of flushing and approximately 40% in 5 PV and finally 7 PV showed about 60%. The glass column test showed 3 ~ 12% higher removal efficiency than that of acrylic test until 5 PV of flushing. However, there was no difference in TPH removal efficiency when 7 PV of surfactant was finally flushed. Both of alum only and alum+polymer mixed surfactants showed also the best coagulation efficiency in $150mg\;L^{-1}$ of concentraion. When Tween 80 was newly dissolved in 0.1% to the recovered solution after the coagulation treatment, the removal efficiency was increased from 32.0% to 41.0% in comparison to the new 0.1% Tween 80 solution without reuse by coagulation treatment.

• Journal of radiological science and technology
• /
• v.25 no.1
• /
• pp.63-71
• /
• 2002

The aim of this study Is to develop a simple and fast method which computes in-vivo doses from transmission doses measured doting patient treatment using an ionization chamber. Energy fluence and the dose that reach the chamber positioned behind the patient is modified by three factors: patient attenuation, inverse square attenuation. and scattering. We adopted a straightforward empirical approach using a phantom transmission factor (PTF) which accounts for the contribution from all three factors. It was done as follows. First of all, the phantom transmission factor was measured as a simple ratio of the chamber reading measured with and without a homogeneous phantom in the radiation beam according to various field sizes($r_p$), phantom to chamber distance($d_g$) and phantom thickness($T_p$). Secondly, we used the concept of effective field to the cases with inhomogeneous phantom (patients) and irregular fields. The effective field size is calculated by finding the field size that produces the same value of PTF to that for the irregular field and/or inhomogeneous phantom. The hypothesis is that the presence of inhomogeneity and irregular field can be accommodated to a certain extent by altering the field size. Thirdly, the center dose at the prescription depth can be computed using the new TMR($r_{p,eff}$) and Sp($r_{p,eff}$) from the effective field size. After that, when TMR(d, $r_{p,eff}$) and SP($r_{p,eff}$) are acquired. the tumor dose is as follows. $$D_{center}=D_t/PTF(d_g,\;T_p){\times}(\frac{SCD}{SAD})^2{\times}BSF(r_o){\times}S_p(r_{p,eff}){\times}TMR(d,\;r_{p,eff})$$ To make certain the accuracy of this method, we checked the accuracy for the following four cases; in cases of regular or irregular field size, inhomogeneous material included, any errors made and clinical situation. The errors were within 2.3% for regular field size, 3.0% irregular field size, 2.4% when inhomogeneous material was included in the phantom, 3.8% for 6 MV when the error was made purposely, 4.7% for 10 MV and 1.8% for the measurement of a patient in clinic. It is considered that this methode can make the quality control for dose at the time of radiation therapy because it is non-invasive that makes possible to measure the doses whenever a patient is given a therapy as well as eliminates the problem for entrance or exit dose measurement.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
• /
• 2004.10a
• /
• pp.145-149
• /
• 2004

It is necessary for managing a perfect process for degasing aluminum molten metal according to the increase of a grade of aluminum and its alloy products. There are some methods that have been used to manage a degasing process in recent years, such as an injection method that uses aluminum molten metal powder and chemicals supplier and input method that supplies argon and nitrogen, or chlorine gas by using a gas blow-tube. However, these methods show some problems, and it shows that it is a difficult process to handle. pollution due to the producing a lot of toxic gases like chlorine and fluoride gas. irregular effects, and lowering work efficiency due to the excessive processing time. The problems that are the most fatal are the producing a lot of sludge due to the reaction of aluminum molten metal with chemicals. loss of metals, and decreasing the life of refractory materials. In order to solve these problems. this paper develops a technology that is related to aluminum continuous casting molten metal and monolithic degasing apparatus. A degasing apparatus developed in this study improved the exist ing methods and prevented environmental pollution wi th smokeless. odor less, and harmlessness by using a new method that applies argon and nitrogen gas in which the methods used in the West and Japan are eliminated. The developed method can significantly reduce product faults that are caused by the production of gas and oxidation because it uses a preprocessed molten metal with chemicals. In addition. the amount of the produced sludge can also be reduced by 60-80% maximum compared with the existing methods. Then. it makes it possible to minimize the loss of metals. Moreover. the molten metal processing and settling time is also shortened by comparing it with the existing methods that are applied by using chemicals. In addition, it does much to improve the workers' health, safety and environment because there is no pollution. The improvement of productivity and prevent ion effects of disaster from the results of the development can be summarized as follows. It will contribute to the process rationalization because it does not have any unnecessary processes that the molten metal will be moved to an agitator by using a ladle and returned to process for degasing like the existing process due to the monolithic configuration. There are no floating impurities due to the oxidation caused by the contact with the air as same as the existing process. In addition. it can protect the blending of precipitation impurities. Because it has a monolithic configuration. it can avoid the use of additional energy to compensate the temperature decreasing about 60t that is caused by the moving of molten metal. It is not necessary to invest an extra facilities in order to discharge the gas generated from a degasing process by using an agitator. The working environment can be improved by the hospitable air in the factory because the molten metal is almost not exposed in the interior of the area.

• Journal of the Korean Applied Science and Technology
• /
• v.32 no.4
• /
• pp.758-766
• /
• 2015

Dextran is a generic term for a bacterial exopolysaccharide synthesized from sucrose and composed of chains of D-glucose units connected by ${\alpha}$-1,6-linkages by using dextransucrases. Dextran could be used as vicosifying, stabilizing, emulsifying, gelling, bulking, dietary fiber, prebiotics, and water holding agents. We isolated new strain capable of producing dextran from Korean traditional kimchi and identified as Leuconostoc sp. strain JYY4. Batch fermentation was conducted in bioreactor with a working volume of 3 L. The media was MMY and 15% (w/v) sucrose. Mineral medium consisted of $3.0g\;KH_2PO_4$, $0.01g\;FeSO_4$, $H_2O$, $0.01g\;MnSO_4$, $4H_2O$, $0.2g\;MgSO_4\;7H_2O$, 0.01 g NaCl, $0.05g\;CaCl_2$ per 1 liter deionized water. The pH of media was initially adjusted to 6.0. The inoculation rate was 1.0% (v/v) of the working volume. Temperature was maintained at $28^{\circ}C$. The agitation rate was 100 rpm. The production pattern of dextran was associated with the cell growth. After 24 hr dextran reached its highest concentration of 59.4 g/L. The sucrose was consumed completely after 40 hr. Growth reached stationery phase when sucrose became limiting, regardless of the presence of fructose or mannitol. When the specific growth rate was 0.54 hr-1, utilization averaged 5.8 g/L-hr. The yield and productivity of dextran were 80% and 2.0 g/L-hr, respectively. Dextrans produced by were separated to two different size by an alcohol fraction method. The size of high molecular weight dextran (45% alcohol, v/v), less soluble dextran, was between MW 500,000 and 2,000,000. Soluble dextran (55% alcohol, v/v) was between 70,000 and 150,000. The molecular weight average of total dextran (70% alcohol, v/v) was between 150,000 to 500,000. The enzymatic hydrolyzates of total dextran of ATCC 13146 showed branched dextrans by Penicillium dextranase contained of glucose, isomaltose, isomaltotriose, and isomaltooligosaccharides greater than DP4 (degree of polymerization) that had branch points. Compounds greater than DP4 were branched isomaltooligosaacharides. Hydrolysates by the Lipomyces dextranase produced the same composition of oligosaccharides as those by Penicillin dextranase.