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        검색결과 827

        661.
        2016.01 KCI 등재 서비스 종료(열람 제한)
        The objective of this study is to investigate the potential use of MSW incineration fly ash as an economic material for the removal of heavy metals (Pb, Mn, Fe, and Cu) from AMD. Batch adsorption experiment was conducted to examine the effects of pH, adsorbent dosage and contact time on metal ions removal in synthetic AMD using MSW incineration fly ash. Precipitation of calcium hydroxide and sodium hydroxide was used for comparison with MSW incineration fly ash by adjusting the pH (5 ~ 11) by coagulation method with 20 min reaction time. Comparing the application of Ca(OH)2 and Na(OH), fly ash proves more efficient which may be due to its porosity and chemical composition. The results from adsorption studies showed that maximum adsorption rate was achieved at 0.4g dose when various fly ash dosages were added to the solution with 60 min optimum time and removal efficiency of heavy metals was over 96%. The effectiveness of fly ash can be related to its high calcium (CaO 55%) content. Efficiency of heavy metals removal was directly linked to the amount of fly ash in the reaction mixture and to the final pH attained. pH plays a significant role in heavy metal uptake. The main removal mechanism was adsorption at the surface of the fly ash together with the precipitation and co- precipitation from the solution with chemicals. Therefore the use of MSW incineration fly ash for treatment of AMD would represent a new market opportunity for this waste product. It can also be useful for neutralizing AMD and possibly reduce its adverse effects to the environment with efficient removal of metal ions from AMD.
        662.
        2015.12 KCI 등재 서비스 종료(열람 제한)
        This study investigated structure and function of the reproductive system in Aplysia kurodai by means of anatomical, histological, and histochemical observation. Reproductive system of this species is consisted of ovotestis, small hermaphroditic duct, ampulla, accessory genital mass and large hermaphroditic duct. The ovotestis is composed of a large number of follicles, and both oocytes and spermatocytes matured in the same follicle. The small hermaphroditic duct is a single tube and contains a swelling, the ampulla, which functions as a storage organ for endogenous sperm and an oviduct. The accessory genital mass is connected to both the small and large hermaphroditic duct, and consisted of three glands: albumen, membrane (winding) and mucus gland. The albumen gland is consisted of granular cells producing basophilic and neutral mucopolysaccharides. The membrane and mucus gland are consisted of granular cells producing acidophilc and sulfated mucopolysaccharides. The large hermaphroditic duct is a single tubular gonoduct linking the accessory genital mass to the common genital aperture but is consisted of two parallel compartments. Internally, these two compartments are incompletely divided by internal septum or fold, which are called as the red hemiduct and white hemiduct, respectively. The red hemiduct functions as an oviduct and the white hemiduct functions as a copulatory duct. The reproductive system of A. kurodai is externally comprised a single tube, i.e., monaulic type. However, internal structure of duct is incompletely divided into oviduct and copulatory duct, i.e., the oodiaulic type.
        663.
        2015.11 서비스 종료(열람 제한)
        Acid mine drainage (AMD) has emerged as one of the greatest environmental threats facing mining industry owing to its characteristic low pH, high acidity and elevated concentrations of metals and sulphate content. This study evaluates the efficiency of fly ash as a low cost material to remove heavy metals (Cu, Fe, Mn and Pb) from AMD. The effects of varying contact time, dosage and pH on adsorption were investigated using synthetically prepared AMD. The experiments was conducted in series of batches for adsorption using a mechanical shaker with 50mL AMD at various dosages of fly ash (0.1 - 0.8g/L) and coagulation using a standard jar tester of 1000mL AMD with chemical coagulant dosages (0.5 - 10g/L). Tests were also conducted with 50mL AMD without fly to evaluate the treatment efficiency of fly ash to chemicals. All tests were performed in duplicate for consistency and accuracy. The chemical composition of fly ash was characterized by X-ray fluorescence (XRF) and the result shows the fly ash is rich in calcium (CaO 54.9%). Leaching test of the fly ash was conducted using KLST and TCLP method to compare the results and evaluate the behavior of leaching ash in replenishing acidic media at low pH such as acid mine drainage. pH plays a significant role in heavy metal uptake in this study with increased in pH value the removal rate increased. The optimum dosage for Adsorption was found to be 0.4g/L with 60 min optimum contact time and coagulation 6mg/L with reduced metal concentrations much less than regulation standards for Cu, Fe, Mn and Pb. From all tests conducted fly ash proves more efficient with over 96% removal even at low dosages. The effectiveness of the treatment process will depend on the quality of the fly ash and the AMD. Therefore the use of fly ash for treatment of mine wastewater would represent a new market opportunity for this waste product. Recycling of fly ash will conserve the natural raw materials and abridge the disposal cost. It will also create new revenues and business opportunities while protecting the environment. Most significantly, the two waste products acid mine drainage and fly Ash could be neutralized and when reacted together to produce much cleaner water broadly compared to post process water derived from Lime treated AMD and sulfates removal rates were in the range of 90% in both experiments. Fly ash is more economical, sustainable.
        664.
        2015.09 서비스 종료(열람 제한)
        Light characteristics are very specific in the aquatic environment. Fish vision and different light spectra perception are related to each species’ natural habit. Light is one of the main environmental conditions and can be easily manipulated in artificial rearing settings. Mucus-secreting goblet cells are the main regulators of digestion. In this study, we established whether the light spectrum (natural condition, full spectrum: green, 520 nm; red, 590 nm, and blue, 480 nm) influences growth performance and digestive activity related to mucus-secreting goblet cell activity in order to develop a good management protocol and optimal rearing system for nursery stage of Epinephelus akaara. For each light spectrum, fish (11.5 ± 0.2 g in mean initial body weight, 9.0 ± 0.1 cm mean initial total length) were reared 16 weeks under a flow-through system and fed commercial pellet diets twice daily. At the end of the experiment, the final body weights differed among the fish reared under different light spectra. The highest growth performance value and feed efficiency were observed in fish reared under the green light condition. Mucus-secreting goblet cell activity was significantly higher in the fish under green light condition than in the fish under the natural, red, and blue light conditions. Rearing of E. akaara under the green light condition had positive effects on fish growth performance and digestion. We recommend that the appropriate light spectrum for nursery stage of E. akaara is the green light condition from the perspective of growth performance and the synergistic effects of mucus-secreting goblet cells. However, longer light treatment periods are needed in future investigations to clarify the effects of light spectrum on each growing stage of E. akaara.
        665.
        2015.09 서비스 종료(열람 제한)
        To overcome the risk of the ovarian hyperstimulation syndrome (OHSS) in patients have polycystic ovarian syndrome (PCOS) and to prepare emergency fertility preservation in patients undergoing anticancer treatment, several researchers have reported IVM of oocytes retrieved from ovaries exposed by only hCG priming. However, the maturation rate and the developmental potential of embryos from IVM oocytes are significantly lower than those of oocytes matured in vivo. Here, we investigated the optimal time point for immature oocyte collection at post hCG only injection for in vitro maturation, in vitro fertilization and blastocyst formation. Immature GV oocytes were collected from 25 days old B6D2F1 female mouse at 12 hr, 14 hr, 16 hr or 24 hr post hCG injection. Oocytes were collected from antral or late secondary follicle by puncturing with 26 G needle. Collected oocytes were cultured in G2 medium with 10% FBS, FSH, estradiol, and hCG for 16 hr in vitro and subjected in vitro fertilization and further embryonic development. To examine follicular maturation, we estimated the numbers of primordial, primary, secondary follicle and antral follicle on ovaries of each time point post hCG. To confirm the optimal time point post hCG injection for collecting immature oocytes, we recovered the oocytes from each time point. There is no difference in the number of oocytes per mice. Oocytes collected at 14 hr post hCG injection were shown higher maturation rate to MII stage and blastocyst formation compare to other three groups (p<0.01). However, there is no difference in the maturation rate on the other three groups. Also, apoptotic signal with TUNEL assay or anti-PARP staining was not change in ovaries from all experimental groups. Granulosa cell proliferation test with anti Ki-67 or anti AMH was not show any difference. According to these results, there are no significant differences in four different time points at 12 hr, 14 hr, 16 hr or 24 hr of collection of immature oocytes in hCG primed mouse. However, oocytes from 14 hr post hCG injection showed higher percentages of maturation rate, in vitro fertilization rate, blastocyst formation.
        666.
        2015.09 서비스 종료(열람 제한)
        Cryopreservation has become a powerful method of the assisted reproduction technology and supports fertility preservation of cancer and other indication patients. After controlled ovarian hyperstimulation, surplus oocytes and embryos were recommended to store using cryopreservation. Recently, vitrification is replaced with traditional slow freezing protocol, because of improved survival rates and clinical outcomes. Vitrification requires a high concentration of CPAs that may induce significant osmotic and metabolic damage to cells including oocytes even in a short exposure of a few minutes. Generally, MPF plays a crucial role in the cell cycle regulation and maintaining the meiotic arrest of oocytes. In fact, it has been observed to decline in MII ovine oocytes after vitrification and would be suggested that one of the main causes of low fertilization rate and developmental competence derived from cryoinjury during vitrification. Therefore, the aim of this study was to evaluate the effect of caffeine treatment on the activity of MPF, MAPK level in vitrified/warmed mouse mature eggs. Caffeine, Phosphataseinhibitor, may maintain active form of MPF. We evaluated their survival after warming procedure, fertilization, cleavage, and developmental rates. Ovulated MII eggs were retrieved from 6 weeks old B6D2F1 female mouse at 14hr post hCG injection. Collected MII eggs were maintained in HTF medium containing 10% KSR with or without caffeine for 1hr. Eggs were vitrified in 7.5%EG +7.5%DMSO equilibrium solution, 15%EG + 15%DMSO + 0.5M sucrose vitrification solution with or without caffeine. Also warming solution contained sucrose (0.5M, 0.25M, 0.125M, and 0M) with or without caffeine. After warming, eggs were cultured in HTF medium with or without caffeine for 2 hr then fertilized with epididymal sperm in vitro and cultured in KSOM for 5 days to analyze embryonic development. Survival rates were similar in all experimental groups. However, fertilization rate was higher in with caffeine group compare to without caffeine significantly (80% vs. 85%, p<0.05). 2-cell and blastocyst formation were increased in caffeine group (p<0.05). MPF activity and MAP kinase activity were recovered in with caffeine group after vitrification/warming process. In conclusion, Caffeine may maintain MPF and MAPK level in vitrified/warmed MII eggs, and enhance fertilization and further embryonic development.
        668.
        2015.07 서비스 종료(열람 제한)
        In this study, genetic diversity of wild Codonopsis lanceolata collected in Korea were analysed using SSR makers. Wild C. lanceolata roots were collected in Jeollanam-do Jangheung-gun Choentae Mountain as in roots. The wild C. lanceolata plants were cultivated in Chungbuk National University greenhouse and the leaves were sampled from 36 plants. The genomic DNA of C. lanceolata was extracted using CTAB. PCR was performed using a program of 35 cycles at 94℃ for 30 sec, 60℃ for 30 sec, and 72℃ for 30 sec with an pre-denaturation of 94℃ for 5 min and a final extension of 72℃ for 30 min. The PCR reaction mixture contains 5 pmole of primers and 20 ng of DNA template in a 20 μL reaction volume. The genotype of the analyzed samples were very different. Therefore, the wild C. lanceolata collected in Korea look genetically diverse.
        669.
        2015.07 서비스 종료(열람 제한)
        Codonopsis lanceolata is a perennial climber. The roots are used as medicinal materials or vegetables. Recently, demand for C. lanceolata is increasing as a healthy food. C. lanceolata is distributed in India and East Asia such as China, Japan as well as Korea. In South Korea, this plant is widely cultivated in Gangwon-do province. No C. lanceolata varieties were developed in Korea. The objective of this study is to analyze genetic diversity of C. lanceolata cultivated in Korea using SSR makers. C. lanceolata roots were collected in each region were cultivated in Chungbuk National University greenhouse. Samples were obtained from fresh leaves of 5 plants from each collection region. The genomic DNA was extracted using CTAB. Genetic diversity was analysed using 4 sets of C. lanceolata SSR makers. PCR was performed in total 20 μL reaction volume containing 20 ng of DNA template, 5 pmole of primers. The genotypes of the analyzed samples were very similar. That means that the genetic diversity of C. lanceolata cultivated in Korea is very low.
        670.
        2015.07 서비스 종료(열람 제한)
        FLOWERING TIME CONTROL PROTEIN, FPA gene encode RNA Recognition Motif (RRM) domain protein and plays important roles in flowering time control in Arabidopsis. Floral transition is significant for reproductive products in all flowering plants. However, little is known about the functions of Medicago autonomous pathway gene. We had cloned the FPA gene on Medicago based on the sequence similarity of Arabidopsis FPA sequence. The RT-qPCR analysis of MtFPA expression patterns showed that the MtFPA transcripts accumulated ubiquitously in roots, leaves, stems, flowers, and pods. When fused to the green fluorescence protein, MtPFA-GFP was localized in the nucleus as speckle pattern of protoplast from Arabidopsis. To examine the function of MtFPA, 35S::MtFPA transgenic plants were generated in Arabidopsis late flowering mutant background, fpa-2. Overexpression of MtFPA specifically caused early flowering under long day conditions compared with non-transgenic plants. In MtFPA transgenic lines, AtFLC expression were down-regulated whereas the floral integrators, AtFT and AtSOC1 were up-regulated as compare with control plant. As these results, MtFPA suggest that is a functional ortholog of the Arabidopsis and may play an important role in the regulation of flowering transition in Medicago.
        671.
        2015.07 서비스 종료(열람 제한)
        All kinds of crops including foods, feeds and turf grasses are damaged frequently by various environmental stresses such as drought, salt, cold, and high temperature, which cause the loss of agronomic productivity. Plants cannot escape from environmental stresses. Thus, plants were evolving in the direction of overcoming environmental stresses. Some genes such as ARF, AB13, NAC, HSF, WRKY respond to environmental stresses have been reported in plants. The genes play a role in stress responses pathway of plants, the transcription factor in response to environmental stress. Typically OsWRKY76 increased the low temperature resistance, AtWRKY28 been reported to be related to the environmental stress. Zoysiagrass (Zoysia japonica Steud.) is used primarily useful for the garden or the golf course. But WRKY, environmental stress-related gene, is unknown in zoysiagrass. Here, we report the analyzing of WRKY genes and response by cold, dehydration and senescence stresses in zoysiagrass. Three WRKY gene (ZjWRKY3, ZjWRKY5, ZjWRKY7) cloning from zoysiagrass. It was transformed in arabidopsis and zoysiagrass. It will be a function analysis.
        672.
        2015.07 서비스 종료(열람 제한)
        Anthocyanin has antioxidant and radical-scavenging effects which may protect cells from oxidative damage and reduce risk of cardiovascular diseases and cancer. A new peanut variety “Heuksaeng”(Arachis hypogaea ssp. hypogaea L.) with dark purple peanut skin was developed at the Department of Southern Area Crop Science, NICS, in Milyang in 2014. This variety was developed from the crossing line between cultivar “Iksan 31” with short stem and erect plant type and “Iksan35” with large grain and purple skin. “Heuksaeng” which is semi erect Virginia plant type has 32cm of main stem length and 25 branch number per plant. This also show more resistant to late leaf spot, web blotch and lodging, compared with check variety “Daekwang”. Each pod has two grains with ellipse shape of purple testa and its yield components is composed of 60 mature pods of per plant, 69g of 100-seed weight, 77% of pod shelling ratio in the regional yield trials(RYT). For 3 year regional yield trials the average kernel yield of “Heuksaeng” had 4.25 MT/ha similar to that of check variety. Its seed quality show 26.9% of crude protein and 46.0% of crude oil and 53.4% of oleate in fatty acid composition. Peanut skin of variety “Heuksang” consist of 2 kind of anthocyanin compounds such as 4.67mg/100g of delpinidine-3-glucoside (D3G) and 1.18mg/100g of cyanidine-3-glucoside(C3G). Peanut variety with high anthocyanin conent in skin will be useful to the recent preference of colorful food with healthful functional compounds.
        673.
        2015.07 서비스 종료(열람 제한)
        Peanut is grown worldwide in the tropics and temperate zones primarily as an oilseed crop (38-54%) and protein source(25-30%). A new peanut variety “Daan”(Arachis hypogaea ssp. fastigiata L.) with the high yield potential was developed at the Department of Southern Area Crop Science, NICS, in Milyang in 2014. This was developed from the crossing line between cultivar “Sangpyeong” with short stem and high quality and “Dakwang” with large grain. “Daan” which is Shinpung plant type has 44cm of main stem length and 13 branch number per plant. Each pod has two grains with long ellipse shape of brown testa and yield components is composed of 34 mature pods of per plant, 127g of 100-seed weight, 75% of pod shelling ratio in the regional yield trials(RYT). Seed quality showed 47.8% of crude oil and 28.3% of protein content. This variety also showed more resistant to early leaf spot, late leaf spot, web blotch, stem rot and lodging compared with check variety “Daekwang”. In the regional yield trials “Daan” outyielded check variety by 16% with 5.00 MT/ha for kernel yield.
        674.
        2015.07 서비스 종료(열람 제한)
        Cucumber is a typical monoecious plant with individual male and female flowers, and sex expression in cucumber is mainly determined by three major genes: F/f, M/m and A/a. Gynoecy plays an important role in cucumber hybrid breeding and use of gynoecious lines as maternal parent ensures high productivity. The purpose of this study is to identify a co-dominant molecular marker linked to F locus to distinguish homozygous and heterozygous gynoecious plants for cucumber breeding programme. Firstly, we analyzed the sequence polymorphism of 5 gynoecious and 5 monoecious inbred lines to detect polymorphism to develop the marker linked to F locus. A pair of specific primer based on insertion/deletion polymorphism on branched-chain amino acid transaminase (BCAT) gene was designed and examined the polymorphism in the parents, F1 and F2 segregating population derived from gynoecious (WJEF11) and monoecious (WNEF8) inbred lines. The result showed that the specific fragment amplified with Cs-Female-F/Cs-Female-R, was identified as a co-dominant marker and co-segregated with sex phenotype in F2 population. Furthermore, we present a new linkage map for F locus using Indel markers. This is the first report for the development of F locus specific co-dominant marker which can distinguish homozygous and heterozygous gynoecious and it could be used in marker-assisted selection in cucumber breeding.
        675.
        2015.06 KCI 등재 서비스 종료(열람 제한)
        본 연구는 몽골 돈디고비(Dundgobi)지역에서 채취한 오일셰일과 석탄 시료들의 유기물 기원, 광물조성 및 분광학적 특징에 대해 조사하였다. 채취한 오일셰일 및 석탄시료들은 Rock/Eval과 총유기탄소(Total organic carbon; TOC) 분석을 통해 케로젠(Kerogen) 종류, 수소 함량, 열적 성숙도, 퇴적환경을 확인하였으며, X-선회절 분석과 분광분석을 이용하여 광물조성을 정의하였다. Rock/Eval과 TOC 분석결과, 에뎀트(Eedemt) 광상에서 채취한 샘플들은 미성숙-성숙 단계의 근원암에 해당하며, 풍부한 수소함량을 보이고, I-형, II-형 and III-형의 케로젠 종류를 가진다. 반면 샤인 어스 쿠닥(Shine Us Khudag) 광상에서 채취한 샘플들의 경우 성숙단계의 근원암으로써, I-형, II/III-형 또는 III-형의 케로젠을 함유하는 잠재성을 가진다. 또한 탄소와 황의 함량에 따르면 두 지점의 퇴적환경은 담수성의 퇴적환경인 것으로 확인되었다. X-선회절 분석으로부터 확인한 오일셰일과 석탄시료들의 광물조성은 석영, 방해석, 고회석, 일라이트, 고령토, 몬모릴로나이트, 아놀소클레이스, 조장석, 미사장석, 정장석, 방비석으로 확인되었다. 가시광선-근적외선-단파적외선 분광분석을 통해 오일셰일 시료로부터 1412 nm, 1907 nm의 점토광물 및 수산화성분에 의한 흡광특성, 2206 nm에서 고령토와 몬모릴로나이트에 의한 흡광특성, 탄산염광물인 고회석에 의한 흡광특성이 2306 nm에서 확인되었다. 그러나 오일셰일의 원격탐사적 탐사를 위해서는 유기물 함량에 따른 분광특성에 대한 연구가 수행되어야 할 것으로 사료된다.
        676.
        2015.05 서비스 종료(열람 제한)
        This study has intended to analyze the characteristics of Resource Circulation Networks: Focused on Chungbuk Eco-Industrial Park (EIP). To reach the goal, this study has divided the networks into such fields as energy, waste, and water, and analyzed the characteristics of each field's projects, already finished or in process, in accordance with network development process, environment, and economy. This study analyzed promotion system and treatment method of the network projects for network development process, and environmental pollution load decrease and air pollutants for environment, and treatment cost reduction, resource purchase cost reduction, etc. for economy. This study found the following results: 1) as for promotion system and business type in network development process field, 8 projects adopted corporate-led system and recycling network, and 3 projects governance system and value-added network project respectively; 2) as for environmental pollution load reduction, air pollutant reduction in environment field, both all projects in water and 6 projects in waste have reduced 92,800 t/year of pollution loads, and all projects in energy and 6 projects in waste have reduced 66,000 t/year of air pollutants, especially 48,000 t CO2/year; and3)as for economic benefits in economy field, it has been found that total economic benefits are 30 billion won.
        677.
        2015.04 KCI 등재 서비스 종료(열람 제한)
        아바타는 <나의 분신>이라 불리는 사이버상에서 캐릭터를 이르는 단어로, 본 연구에서는 MMORPG 게임에서 자신을 치장하며 실제 자기표현과 이상화(理想化) 기능을 하는 캐릭터로 정의하 였다. 본 연구를 통해 멀티 아바타와 성별 전환 사이에서 작동하는 유병률(有病率)을 설명하는 것을 목적으로 하였다. 본 실험을 위하여 선행된 방법은 유저에게 지정된 게임 연습과 질문을 미리 제공하 였고, 이는 선행적으로 사용자에게 게임 동기를 발생하여 아바타 생성에 도움을 주고자하는 것이 목 적이었다. 본 연구를 통해 연령, 성별과 성전환 사이에 상관관계를 살펴보았고, 비 전형적인 방식에서 는 성전환 가능성이 높아졌고 일반 참가자 또한 절반의 성전환 선택의 경향을 보여주었다. 마지막으 로, 경험의 성격 특성에 대한 경험에 대한 개방성은 성별과 유사한 상관관계를 보였다.
        678.
        2015.03 KCI 등재 서비스 종료(열람 제한)
        This study investigated possible involvement of photoperiodic regulation in reproductive endocrine system of female olive flounder. To investigate the influence on brain-pituitary axis in endocrine system by regulating photoperiod, compared expression level of Kisspeptin and sbGnRH mRNA in brain and FSH-β, LH-β and GH mRNA in pituitary before and after spawning. Photoperiod was treated natural photoperiod and long photoperiod (15L:9D) conditions from Aug. 2013 to Jun. 2014. Continuous long photoperiod treatment from Aug. (post-spawning phase) was inhibited gonadal development of female olive flounder. In natural photoperiod group, the Kiss2 expression level a significant declined in Mar. (spawning period). And also, FSH-β, LH-β and GH mRNA expression levels were increasing at this period. However, in long photoperiod group, hypothalamic Kiss2, FSH-β, LH-β and GH mRNA expression levels did not show any significant fluctuation. These results suggest that expression of hypothalamic Kiss2, GtH and GH in the pituitary would change in response to photoperiod and their possible involvement of photoperiodic regulation in reproductive endocrine system of the BPG axis.
        679.
        2015.02 서비스 종료(열람 제한)
        Clogging of the filter media which is brought by physical, chemical, and biological factors tend to reduce the lifespan of filters and remains a challenge. In this study, a laboratory column test method was used to investigate the evolution of physical and biological clogging in a non-vegetated filter media system with layers of sand, gravel, and woodchip. Blank column tests using either sand or gravel were conducted and investigated. Several column setups with varying arrangements and particle sizes of sand and gravel were also prepared to identify the best filter media combination that is least susceptible to clogging without compromising the treatment capacity. Artificial stormwater runoff was introduced in the system at a specific hydraulic loading rate (HLR) and influent characteristics. The degree of clogging was quantified by monitoring the variations in the hydraulic head at different levels of the columns. Water samples were also collected, tested, and analyzed at the end of each test run in order to measure the treatment efficiency of the filter. The insights and results of this study can justify the physical and biological clogging formation in filter media and therefore be used to suggest some filter media particle size modifications that can help to improve the sediment removal and treatment performance. Moreover, it can also aid to reduce the maintenance frequency and costs of a stormwater filter system.
        680.
        2014.12 KCI 등재 서비스 종료(열람 제한)
        Autophagy is a homeostatic degradation process that is involved in tumor development and normal development. Autophagy is induced in cancer cells in response to chemotherapeutic agents, and inhibition of autophagy results in enhanced cancer cell death or survival. Chloroquine (CQ), an anti-malarial drug, is a lysosomotropic agent and is currently used as a potential anticancer agent as well as an autophagy inhibitor. Here, we evaluate the characteristics of these dual activities of CQ using human colorectal cancer cell line HCT15. The results show that CQ inhibited cell viability in doseand time-dependent manner in the range between 20 to 80 uM, while CQ did not show any antiproliferative activity at 5 and 10 uM. Cotreatment of CQ with antitumor agent NVP-BEZ235, a dual inhibitor of PI3K/mTOR, rescued the cell viability at low concentrations meaning that CQ acted as an autophagy inhibitor, but CQ induced the lethal effect at high concentrations. Acridine orange staining revealed that CQ at high doses induced lysosomal membrane permeabilization (LMP). High doses of CQ produced cellular reactive oxygen species (ROS) and cotreatment of antioxidants, such as NAC and trolox, with high doses of CQ rescued the cell viability. These results suggest that CQ may exert its dual activities, as autophagy inhibitor or LMP inducer, in concentration-dependent manner.