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        검색결과 9,938

        3921.
        2016.10 구독 인증기관·개인회원 무료
        Many species of braconids play an important role in controlling the populations of insects in agricultural and natural ecosystems, which parasitize pests. Nevertheless, the family Braconidae was scarcely research and DNA barcoding of Braconidae has not been studied in Korea. DNA barcoding can rapidly perform species identification, and classify difficult species in morphological identification. Because most braconids are very small and cryptic in morphology, DNA barcoding is useful in Braconidae taxonomy. In this study, genomic DNA of 280 individual samples were extracted, and, among them, 208 samples were obtained COI (cytochrome c oxidase I) barcode sequences. As a consequence of blast, 48 samples were identified in genus-level, and 51 sample were identified in species-level. Among them, 4 species were revealed as unrecorded in Korea.
        3922.
        2016.10 구독 인증기관·개인회원 무료
        Cycloamyloses (CA) from high-amylose rice starch (Dodamssal, 50.94% amylose) was produced to form a complex with anthocyanin extracted from black rice (sihtoheukmi). The effects of CA concentration (1, 5, 10 and 30%, w/v), pH (2, 4, 6, and 8), UVB irradiation time (~24h) and thermal treatment time (~24h) on the oxidant capacity of the complex were investigated. Anthocyanin consisting of 95% cyanidin-3-glucoside (C3G) was extracted from the black rice by suspending in 60%(v/v) ethanol containing 0.2%(v/v) hydrochloric acid for 90 min at 50°C. Cycloamyloses (CA) produced by 4-α-glucanotransferase (4αGTase) formed complexes with C3G by shaking the mixture for 48 hours at 30°C. Antioxidant activities (radical scavenging capacity) were determined by using ABTS [2,2'-azinobis-(3-ethylbenzothiazoline- 6-sulfonic acid)]. The antioxidant activities of the complexes increased with pH increasing. Upon UVB irradiation and heat treatment, the antioxidant activities were more retained for the complexes incorporating 10% CA concentration or above compared to the C3G control. Degradation rate constant (Kd) and half-life (T1/2) were obtained from degradation data of CA complex with cyanidin-3-glucoside. The effect of CA complex formation with C3G is significantly observed at pH4. The results suggest that the CA complex formed with C3G indeed has an enhanced antioxidant potential toward UVB and thermal degradation.
        3923.
        2016.10 구독 인증기관·개인회원 무료
        Ionic liquids (ILs) have been used in DNA extraction/separation, DNA preservation and PCR based on their characteristic affinity to DNA. However, few studies have been performed about how DNA-IL complex forms and its mechanism which would be essential to understand the role of ILs over the range of applications. Herein, we present that the differences in the structure of the DNA- IL complex are associated with the alkyl chain length of IL. The assumption was evidenced by Atomic force microscopy, DNA specific dye staining, gel-electrophoresis and real-time electrical measurement. We observed unique electrical signals with altered duration time and amplitude when DNA- ILs complexes pass through solid-state nanopore. We examined three types of ILs (EMIM-Cl, BMIM-Cl, and OMIM-Cl) for their characteristics to form DNA-ILs complexes. The results indicated that the length of hydrophobic alkyl group in respective ILs determines the form of DNA-IL complex. In conclusion, the morphology of DNA could be modified by the incorporation with different alkyl chain length of ILs, providing their further application in biosensor such as nanopore technique for DNA sequencing or understanding protein-DNA interaction.
        3924.
        2016.10 구독 인증기관·개인회원 무료
        To increase the stability of anthocyanin from black rice, β-cyclodextrin (β-CD) formed a complex with anthocyanin, and thermal and UVB stability of the complex was investigated at various pH levels. The formation of β-CD complex with anthocyanin was confirmed by the decreased UV-Vis spectrophotometer absorbance (at 511nm) with increasing the concentration of β-CD at pH 2, 2.5, 3, 4, and 5. ABTS (2, 2’-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid)assay was conducted to measure radical scavenging capacity (RSC) of the complex at pH 2, 4, 6, and 8, after which the RSCs were recorded over the 24 h heating(95°C) and 24 h UVB irradiating periods. The RSC values of the complexes increased as the β-CD concentration increased (0.1-2%) at pH 6 and 8. Upon thermal treatment, the RSC readings of the complexes tended to decrease to a lesser extent compared to the anthocyanin control (without β-CD) at pH 2. This result suggests that the thermal stability of anthocyanin was more retained in the presence of β-CD at low pH (pH 2). However, in the case of UVB irradiation, the effect of β-CD complex on the anthocyanin RSC was not significant, though the RSC values for both the anthocyanin control and complexes trended downward as the UVB irradiation time increased at all pH ranges except for pH 8 (no downward trend). In short, this study suggests that the effect of β-CD complex on the stability of anthocyanin antioxidant capacity depends on pH and the susceptibility to the degradation process.
        3925.
        2016.10 구독 인증기관·개인회원 무료
        Although carnosic acid (CaA) is known as one of the useful polyphenolic compounds due to its antimicrobial and antioxidant activities, it is limited to use as aqueous solution because of its low solubility and unstability. The objective of this study was to investigate the capability of CA to improve the solubility of CaA by forming an inclusion complex in comparison with cyclodextrin (CD) and maltodextrin (MD). Enzymatically-produced CA was reacted with CaA in aqueous solution to form a complex using a freeze-drying. And the formation of complex between CaA and CA was identified by X-ray diffraction (XRD), differential scanning calorimeter (DSC) and field emission scanning electron microscope (FESEM). As a result of XRD and DSC analysis, disappearance of characteristics of CaA that was reacted with CA could be indicated the complex formation between CaA and CA. The formation complex of CaA with CA was also confirmed through the change in morphology of CaA and CA in the electron micrograph result. Aqueous solubility of CaA with various concentrations (1, 5, 10, 20, 30%) of CA was measured by absorbance change at 285 nm. As a result, the solubility of the CaA was significantly increased with increasing CA concentration. At 30% CA, the maximum solubility of CaA was 0.095% (w/v) in solution, which was approximately 3 times higher than that of free CaA (0.033%). The effect of inclusion complex with CA on the solubility of CaA was superior than that with CD (0.057%) and MD (0.066%). These results indicated that the effects on the solubility and formation abilities of inclusion complex were associated with host materials and its concentration rate. This study confirmed that the CA can be a viable solution to improve the aqueous solubility of CaA. Further investigation is still needed to understand the effect of inclusion complex with CA.
        3926.
        2016.10 구독 인증기관·개인회원 무료
        Various methods for the detection of E. coli O157:H7 in food have been developed in the past decades. However, current detection methods require specialized instruments and lengthy preparation time. In an effort to achieve a rapid and sensitive detection, we developed a radial chromatography (RC) biosensor integrated with gold nanoparticle (AuNP) conjugated with antibody for the detection of E. coli O157:H7. The immuno-AuNP binds to E. coli O157:H7 creating AuNP-E. coli O157:H7 complexes by specific antigen-antibody interaction. The AuNP-E. coli O157:H7 complexes can be identified clearly from free AuNP by RC based on their mobility on porous matrix. Thus, the AuNP complexed with target bacteria, E. coli O157:H7 could be discriminated from free AuNP by radial chromatography. The results showed that the developed RC biosensor is highly selective to E. coli O157:H7 over non-target bacteria, including Bacillus cereus, Staphylococcus aureus and Vibrio cholerae with a detection limit of 105 CFU/ml. When combined with a pre-concentration step using immunomagnetic beads, we could further enhance the detection limit down to 103 CFU/ml. In this study, we developed a novel method that is rapid, sensitive and applicable for qualitative and quantitative detection of E. coli O157:H7. The detection procedure is simple and the results can be easily determined by naked eyes, suggesting that this system is practical and can be applied to the field diagnosis in food industry for the detection of pathogenic bacteria.
        3927.
        2016.10 구독 인증기관·개인회원 무료
        Recently, there is a growing interest of consumers in natural products thus a large number of natural preservatives have been studied as food additives. Among those natural preservatives, rosemary extract are commonly used by the food industry to extend the shelf life of several products. Nevertheless, the incorporation of the rosemary extract in food matrix is highly limited due to the low water solubility and poor chemical stability of constituents of rosemary extract. In this context, it is needed to find a way that can improve the water solubility to incorporate rosemary extract into aqueous system like foods. Hence, in this study we added surfactants that have a relatively high hydrophilic-liphophilic balance number into rosemary extract solution to increase the water solubility of rosemary extract and then investigated the microbial activities of rosemary extract with surfactants. Tween 20, decaglycerol monooleate, decaglycerol laurate and decaglycerol myristate were used in a range 0.1~4% and rosemary-surfactant solution was prepared by dissolving rosemary in surfactant added phosphate buffer (pH 7) as much as extract can be dissolved. Water solubility of rosemary-surfactant solution were examined by observance of the UV-vis spectra. The antimicrobial effects rosemary-surfactant solution on B.subtilis were also examined by paper disc diffusion method. Rosemary extract showed poor solubility in normal phosphate buffer but its water solubility was highly increased when surfactant was added. This tendency was lasted at all types of surfactant. This is because of amphipathic property of surfactant. Antimicrobial effect to B.subtilis was observed when a relatively lower concentration of surfactants were used, however, not in high concentrations. This result might be attributed to the formation of surfactant micelles containing rosemary extract when a relatively higher concentration of surfactants were used. The information presented may be useful for the development of a new rosemary-loaded delivery systems.
        3928.
        2016.10 구독 인증기관·개인회원 무료
        Heavy metals are typical contaminant in water and need to be removed because they are non-biodegradable and can accumulate in human body. To remove metal and other contaminants from water, chemical absorbents are widely used due to their low cost. Herein, hybrid materials comprised of amylose and single wall carbon-nanotube (swCNT) was developed as the absorbent for water purification. A high adsorption properties of carbon-nanotubes have been utilized in designing effective absorbent but its poor dispersity in water is a limiting factor for practical use. Single wall carbon-nanotube was hybridized with amylose chain produced by enzyme reaction of amylosucrase and their tendency to self-assemble in aqueous environment. The amylose-swCNT microparticles were characterized by FE-SEM and turned out to be spherical structure with CNTs embedded throughout the amylose matrix. The ability of amylose-CNT microparticles to remove copper was examined. Concentration of copper was decreased after reaction with amylose-swCNT microparticles. Although amount of decreasing copper was less than swCNT on same total mass, Adsorption efficiency of amylose-swCNT microparticles was good because their swCNT content was only 10% of total mass.
        3929.
        2016.10 구독 인증기관·개인회원 무료
        Opuntia is a cactus with fruits and is also called prickly pear. Extraction process of water soluble fiber from opuntia stem powder was optimized by applying various conditions such as ethanol concentration, temperature and pH. Fiber extraction was highest in 0% ethanol and lowest in 100% ethanol, indicated that hot distilled water extraction produced maximum water soluble fiber. Among temperature range from 50 to 90°C, water soluble fiber was extracted mostly at 50°C and leastly at 90°C, showing decrease in fiber with increase in temperature. On the other hand, pH higher than 7 did not show any significant difference in fiber extraction, while fiber extraction decreased in lower pH 7. Conclusively ethanol hampered extraction of water soluble fiber from opuntia stem powder and extraction was not stable with higher heat and low acidic condition.
        3930.
        2016.10 구독 인증기관·개인회원 무료
        Differences in sugar and salt diffusion rates of cabbage depending on size and part were examined. Whole, 3x3 and 5×5 cube sliced cabbage examined indifferent pickling condition (salt 2, 4, 6, 8% and sugar 5, 10, 15, 20% brix). After 12hr storage, salt absorption depending on part was determined to be higher in leaf, followed by stem in all salt solution. Sugar distribution was also determined to be higher in leaf, followed by stem, showing same trend with salt diffusion. Salt diffusion was found to be highest in 3×3 sliced cabbage. Where as 5×5 sliced cabbage and then whole cabbage showed lower diffusion rate in all brix sugar solution. Size dependent sugar diffusion showed same tendency with size dependent salt diffusion. Also, increase in salt and sugar concentration led to increase in salt and sugar permeation rate.
        3931.
        2016.10 구독 인증기관·개인회원 무료
        Quality characteristics such as texture and sensory properties of garaetteok(Korean rice cake)made with organic rice flour treated withcitric acid were investigated. Compared to rice flour without addition of citric acid,rice flour treated with citric acid showed a significantly lower viscosity and viscoelasticity level as the concentration of citric acid increased. Hardness of garaetteokmade with citric acid showed a similar trend in viscoelasticity changes, whereas cohesiveness was not significantly affected by the pretreatment of citric acid.Garaetteok of 0.5% citric acid pretreatment showed the highest scores in hardness, springiness, chewiness and overall acceptability.However,flavor and taste of garaetteokof citric acid pretreatment were lower than those of the control.
        3932.
        2016.10 구독 인증기관·개인회원 무료
        The objective of this study was to determine rheological properties of cold water-soluble potato starch. Scanning Electron Microscopy (SEM) study showed that granule size of cold water-soluble potato starch was 10-60 μm, and shape was dimple in the middle, likely due to starch shrinkage after swelling during treatment. Cold water-soluble starch was prepared by ethanol (60%) and 3 M NaOH. The cold water solubility of native potato starch was low at 4.43±2.9%, whereas the solubility of cold water-soluble starch was high at 81.01±0.9%. The DSC diagram showed a gelatinization peak temperature of native starch but no such peak for treated starch. In dynamic tests, cold water-soluble starch showed decreased storage modulus (G') and loss modulus (G'') with increasing temperature, while native starch showed a continuous increase in G' and G''. This results indicated that cold water-soluble starch showed different granule structure and rheological properties.
        3933.
        2016.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The antioxidant activity of 70% methanol, 70% ethanol and chloroform-methanol (CM, 2:1, v/v) extracts from turmeric (Curcuma longa L.) was investigated in this study. The antioxidant potential of various extracts of turmeric was evaluated by using different antioxidant tests, namely DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging activity, ABTS [2,2’-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt] radical scavenging activity, ferric reducing antioxidant power and β-carotene bleaching assays as well as total phenol content and total flavonoid content. All extracts exhibited abundant total phenol content, total flavonoid content and strong antioxidant activity. Particularly, higher activity was exhibited by CM extract with 46.32±0.35 mg CAE/g and 15.58±0.39 mg QE/g of total phenol content and total flavonoid content. Generally, antioxidant activity of various extracts from turmeric increased in the following order: 70% methanol extract, 70% ethanol extract and CM extract, respectively. Results suggested that turmeric could be widely used as a source of antioxidant and a kind of functional material in food.
        4,000원
        3934.
        2016.09 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        Tungsten (W) thin film was deposited at 400 oC using pulsed chemical vapor deposition (pulsed CVD); film was then evaluated as a nucleation layer for W-plug deposition at the contact, with an ultrahigh aspect ratio of about 14~15 (top opening diameter: 240~250 nm, bottom diameter: 98~100 nm) for dynamic random access memory. The deposition stage of pulsed CVD has four steps resulting in one deposition cycle: (1) Reaction of WF6 with SiH4. (2) Inert gas purge. (3) SiH4 exposure without WF6 supply. (4) Inert gas purge while conventional CVD consists of the continuous reaction of WF6 and SiH4. The pulsed CVD-W film showed better conformality at contacts compared to that of conventional CVD-W nucleation layer. It was found that resistivities of films deposited by pulsed CVD were closely related with the phases formed and with the microstructure, as characterized by the grain size. A lower contact resistance was obtained by using pulsed CVD-W film as a nucleation layer compared to that of the conventional CVD-W nucleation layer, even though the former has a higher resistivity (~100 μΩ-cm) than that of the latter (~25 μΩ-cm). The plan-view scanning electron microscopy images after focused ion beam milling showed that the lower contact resistance of the pulsed CVD-W based W-plug fill scheme was mainly due to its better plug filling capability.
        4,000원
        3935.
        2016.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Nanosized hollow silica was prepared by Stӧber method in the presence of aluminum isopropoxide. The mixture of polyelectrolytes such as poly(sodium 4-styrene sulfonate)(PSS) and polyacrylic acid(PAA) were used as templates. Tetraethylorthosilicate(TEOS) and aluminum isopropoxide were used as precursors for silica and alumina, respectively. The function of aluminum isopropoxide is to increase the porosity of silica shell. The characterizations of hollow silica were examined by TEM(transmission electron microscopy), TGA(thermogravimetric analysis), BET(Brunauer Emmett Teller), Energy-dispersive X-ray spectroscopy(EDS), and FT-IR spectrum. It was found that the shell thickness of hollow silica was around 8 nm and the core diameter was around 20 nm by TEM.
        4,000원
        3936.
        2016.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        목 적: 저습환경 근로자들은 환경적인 요인으로 건성안이 증가하는 실정이다. 따라서 건성안 선별검사방 법에 따른 유병률을 알아보고, 비교분석하여 이에 따른 기준을 알아보고자 한다. 방 법: 충남지역 이차전지(리튬이온) 생산 공정에서 환경적으로 밀폐된 공간인 클린룸(상대습도 1%미만) 에 근무하는 근로자 543명을 대상으로 하였다. 자각적으로 McMonnies 설문지와 일반적 특성을 설문 조사하 였고, 타각적으로 눈물막 안정성검사와 눈물량 검사를 실시하였다. 결 과: 4개의 건성안 선별검사에서 모두 양성으로 진단 받은 사람은 72명이었고 음성으로 진단 받은 사 람은 471명이었으며, 양성으로 진단 받은 사람 72명과 일반적인 특성과의 상관관계를 분석해 본 결과 수면 시간과 음의 상관관계가 있었다. 건성안 검사방법에 따른 신뢰도 분석한 결과 맥모니 검사가 0.53으로 가장 일치도가 높았으며 타당도 분석인 ROC곡선을 비교결과도 0.90으로 가장 높았다. 건성안 선별검사에서 모두 양성으로 진단받은 환자여부에 관한 예측 적합 모형 분석결과 1차 맥모니검사 후 맥모니검사에서 양성으로 진단받은 환자에 대해 2차 눈물량 검사를 하는 방법이었다. 결 론: 저습 환경 근로자들의 건성안 판정은 수면시간과 유의한 관계를 보였다. 따라서 저습환경 근로자 들의 수면시간을 일반적으로 권고되고 있는 8시간 수면으로 교육하여 수면량 조절을 할 필요가 있다. 본 연 구에서 4개의 건성안 선별검사방법을 비교분석해본 결과 가장 신뢰도와 타당도가 높은 맥모니검사를 눈 건강 검진 시행시 문진에 추가하여 건성안 환자 여부를 판별하는데 도움이 되리라 사료된다.
        4,000원
        3937.
        2016.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Plant nutrition one of the most important factors that increase plant production. Thus, the present study was carried out to investigate the effects of NPK (three main macro elements of fertilizer) and their interactions on morphological and biochemical contents of Deodeok (Codonopsis lanceolata). Results exhibited that application of different fertilization treatments had a considerable effect on the different vegetative growth characteristics of C. lanceolata compared to the non fertilizer control. Plant height showed significant results towards all fertilization group compared to non fertilizer group, and the highest value (266.8 cm) for plant height was observed from the N+P+K group. The growth of internode was converted to vine after node 5, no fertilizer effects were found on internode elongation. Chlorophyll content showed a high amount in the range of 42.8 to 46.6 against all fertilization treatment groups, except P+K group. The highest values (57.0 g) for the fresh weight of roots were obtained from the N+P+K groups compared to non fertilizer group. The mineral nutrient content of Na, Mg, Cu and Al of the roots of C. lanceolata showed the lowest amount from in P+K groups compared to other groups. In addition, P from N+K group, Mn from N+P group and Ca, Fe, Zn from N+P+K group also exhibited the lowest mineral content compared to other groups respectively.
        4,000원
        3938.
        2016.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study was conducted to examine the effects of medium composition on organogenesis towards in-vitro cultured diploid and tetraploid Codonopsis lanceolata and obtain in-vitro mass propagation of superior species of C. lanceolata. Regarding MS medium composition for each concentration, diploid C. lanceolata was found to be declined. However, shoot and adventitious root formation were suppressed with higher mineral salt concentration, and active growth of shootand adventitious root was exhibited as 4.9 cm and 3.2 cm respectively in 1/2 MS medium. While in tetraploid C. lanceolata, it showed 2.9 cm and 3.2 cm respectively in 1/4 MS medium. In the case of sucrose concentration, no consistent decrease was observed for growth of shoot and adventitious root of diploid both at high and low concentration. The growth of shoot (at 3% concentration) and adventitious root (at 7% concentration) was 2.3 cm and 2.0 cm respectively. Although there was no difference in shoot formation of tetraploid C. lanceolata in all concentrations with the range of 1.7 ~ 1.8, there was a slight decrease in shoot growth at high concentration. Results revealed that the adventitious root formation was suppressed at high concentration. Concentration of agar exhibited no significant difference in shoot formation of diploid C. lanceolata at all concentrations. The highest result of adventitious growth (4.1 cm) was observed at 0.8% concentration. Slight inhibition of shoot formation and root formation of tetraploid C. lanceolata was observed at higher concentration. Shoot formation of diploid C. lanceolata also exhibited inhibition at higher concentration. Shoot formation of diploid C. lanceolata was increased at lower pH and shoot growth was the highest (2.3 cm) at pH 3.8. Adventitious root formation was higher at lower pH. Although there was no difference in shoot formation of tetraploid C. lanceolata presenting 1.7 ~ 1.8 regardless of high and low pH, growth inhibition was showed at higher pH. Adventitious root formation and growth showed a little higher result at pH 5.8.
        4,000원
        3939.
        2016.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The hazards associated with the polycyclic aromatic hydrocarbons (PAHs) are known to be recalcitrant by their structure, but white rot fungi are capable of degrading recalcitrant organic compounds. Phlebia brevispora KUC9045 isolated from Korea was investigated its efficiency of degradation of four PAHs, such as phenanthrene, anthracne, fluoranthene, and pyrene. And the species secreted extracellular laccase and MnP (Manganese dependent peroxidase) during degradation. P. brevispora KUC9045 demonstrated effective degradation rates of phenanthrene (66.3%), anthracene (67.4%), fluoranthene (61.6%), and pyrene (63.3%), respectively. For enhancement of degradation rates of PAHs by the species, Remazol Brilliant Blue R (RBBR) was preferentially supplemented to induce ligninolytic enzymes. The biodegradation rates of the three PAHs including phenanthrene, fluoranthene, and pyrene were improved as higher concentration of Remazol Brilliant Blue R was supplemented. However, anthracene was degraded with the highest rate among four PAHs after two weeks of the incubation without RBBR addition. According to the previous study, RBBR can be clearly decolorized by P. brevispora KUC9045. Hence, the present study demonstrates simultaneous degradation of dye and PAHs by the white rot fungus. And it is considered that the ligninolytic enzymes are closely related with the degradation. In addition, it indicated that dye waste water might be used to induce ligninolytic enzymes for effective degradation of PAHs.
        4,000원
        3940.
        2016.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The objective of this study was to determine the effect of nitrification inhibitor dicyandiamide (DCD) and urease inhibitor hydroquinone (HQ) on ammonia (NH3) and nitrous oxide (N2O) emission from pig slurry applied to Timothy (Phleum pretense L.) sward. The daily emission of ammonia (NH3) and nitrous oxide (N2O) was monitored for 9 days in three different treatments; 1) control (only pig slurry application), 2) DCD treatment (pig slurry + DCD), and 3) HQ treatment (pig slurry + HQ). Most NH3 emission occurred after 4~5 days in three treatments. Total NH3 emission, expressed as a cumulative amount throughout the measurement time, was 1.33 kg N ha 1 in the control. The DCD and HQ treatment decreased total NH3 emission by 16.3% and 25.1%, respectively, compared to the control. Total N2O emission in the control was 47.1 g N ha 1. The DCD and HQ treatment resulted in a reduction of 67.9% and 41.8% in total N2O emission, respectively, compared to the control. The present study clearly indicated that nitrification and urease inhibitor exhibited positive roles in reducing N losses through NH3 and N2O emission.
        4,000원