• Journal of the Korean Society of Marine Environment & Safety
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• v.26 no.1
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• pp.84-92
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• 2020

To supply a stable amount of standard material to detect paralytic shellfish toxin (PST), we examined possible increases in toxic content in Alexandrium catenella and A. pacificum using a light emitting diode (LED), which is one of the most eco-friendly and economical lighting method. When comparing the growth rates of organisms and wavelengths of light used, the half saturation constants (Ks) of red wavelength were higher than those of other wavelengths. In contrast, the Ks of blue wavelength were lower than those of other wavelengths. Moreover, when comparing the toxic contents and wavelengths of light used, red wavelength produced approximately 8 times more toxic content in A. catenella and approximately 3.2 times more toxic content in A. pacificum than other wavelengths. Thus, the toxic content present in the organism might be closely related to the Ks of light. The optimum light source to be used to ensure economically ef ective and productive growth in an Alexandrium culture system (photo-bioreactor) would likely consist of a two-phase culture, wherein a blue LED is used during the lag and exponential phases to increase growth rates, followed by the use of a red LED during late exponential and stationary phases to achieve increased PST yields.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.23 no.5
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• pp.255-264
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• 2013

Cobalt aluminate ($CoAl_2O_4$) is a highly stable pigment with excellent resistance to light, weather, etc., which has resulted in widespread use as a ceramic pigment. Due to the unique optical characteristics, $CoAl_2O_4$ is generally used as a coloring agent to decorate porcelain products, glass, paints and plastics. Here, $CoAl_2O_4$ pigments were synthesized by polymerized complex method and solid state reaction. Then $CoAl_2O_4$ pigment were grinded using the attrition milling with 1 mm size zirconia ball for 3 hours. The attrition milling process was performed at the constant speed of 800 rpm and ball to powder weight ratio (BPR) was 100 : 1. The characteristics of synthesized pigment were analyzed by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), particle size analyser (PSA) and CIE $L^*a^*b^*$. The XRD patterns of $CoAl_2O_4$ show single phase spinel structure. The particle size of $CoAl_2O_4$ measured by FE-SEM, TEM and PSA analysis was in the range of 100~200 nm. The blue color of obtained $CoAl_2O_4$ pigments could be confirmed through CIE $L^*a^*b^*$ measurement.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.17
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• pp.7229-7234
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• 2014

Trichoderma spp. are known as a rich source of secondary metabolites with biological activity belonging to a variety of classes of chemical compounds. These fungi also are well known for their ability to produce a wide range of antibiotic substances and to parasitize other fungi. In search for new substances, which might act as anticancer agents, the overall objective of this study was to investigate the cytotoxic effects of Trichoderma harzianum and Trichoderma asperellum cultural filtrates against human cervical and breast cancer cell lines (HeLa and MCF-7 cells respectively). To achieve this objective, cells were exposed to 20, 40, 60, 80 and 100 mg/ml of both T. harzianum cultural filtrate (ThCF) and T. asperellum cultural filtrate (TaCF) for 24h, then the cell viability and the cytotoxic responses were assessed by using trypan blue and 3-(4,5-dimethylthiazol-2yl)-2,5-biphenyl tetrazolium bromide (MTT) assays. Morphological changes in cells were investigated by phase contrast inverted microscopy. The results showed that ThCF and TaCF significantly reduce the cell viability, have cytotoxic effects and alter the cellular morphology of HeLa and MCF-7 cells in a concentration dependent manner. A concentration of 80 and 100mg/ml of ThCF resulted in a sharp decline in the cell viability percent of HeLa and MCF-7 respectively (25.2%, 26.5%) which was recorded by trypan blue assay. The half-maximal inhibitory concentrations ($IC_{50}$) of ThCF and TaCF in HeLa and MCF-7 were recorded as 16.6, 12.0, 19.6 and 0.70mg/ml respectively by MTT assay. These results revealed that ThCF and TaCF have a substantial ability to reduce the viability and proliferation of human cervical and breast cancer cells.

• Journal of Food Hygiene and Safety
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• v.15 no.2
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• pp.108-113
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• 2000

This study was carried out to propose a simple method for the extraction of seven tar dyes such as tartrazine, sunset yellow FCF, amaranth, erythrosine, allura red, brilliant blue FCF and indigo carmine using aminopropyl amine cartridge and to determine the content of the dyes in candies, soft drinks, ice bars and okchuns produced in Korea. The tar dyes were simultaneously analyzed by reverse phase high performance liquid chromatography(HPLC). The recovery rates of the dyes ranged from 65.8% to 99.6%. The contents of the dyes in candies, soft drinks, ice bars and octhuns were N.D.∼50.1 mg/kg, N.D.∼49.9 mg/kg, N.D.∼56.0 mg/kg and N.D.∼867.3 mg/kg, respectively. The types of the dyes used most frequently for candies, soft drinks and ice bars were tartrazine, brilliant blue and amaranth, respectively. Of the samples, tartrazine was used frequently, and indigo carmine was not used at all.

• Korean Journal of Medicinal Crop Science
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• v.16 no.6
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• pp.434-438
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• 2008

To selection of optimal shading material, two-year-old ginseng (Panax ginseng C. A. Meyer) of new cultivar, 'Cheonpoong' (CP), and native species 'Hwangsookjong' (HS) were cultured under three kinds of shading materials such as three-layered blue and a one-layered black PE (polyethylene) net (TBSB), blue PE sheet (BS), and aluminium coated PE sheet (AS) in imperfectly drained paddy soil. Growth characteristics, yield and ginsenoside contents were investigated under three shading materials. Yield and ginsenoside contents of ginseng were distinctly affected by intensity and quality of sunlight penetrated through shading materials. Light transmission ratio, air and soil temperature according to shading materials were higher in order of BS, AS, and TBSB. However, ratio of aerial phase and porosity of the soil were higher in order of AS, BS, and TBSB, respectively. There was no significantly difference in the ratio of rusty colored root by shading materials. CP showed higher stem length, leaf area, and root weight than that of HS, while the former showed distinctly lower discolored leaf ratio than that the other. Eight kinds of ginsenosides content of CP were higher than that of HS in $Rg_1$, Re, Rf, $Rb_1$ and Rc except $Rg_2$, $Rb_2$, and $Rb_3$. Total ginsenoside contents of CP was distinctly higher than that of HS. Total ginsenoside contents as affected by shading materials was higher in order of BS, TBSB, and AS in CP, while TBSB, BS, and AS in HS.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.9
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• pp.1201-1207
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• 2011

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) has been proposed as a potent tool to trigger apoptosis in cancer therapy. However, as many types of cancer cells remain resistant towards TRAIL-induced cytotoxicity, several combined therapy approaches aimed to sensitize cells to TRAIL have been developed. Genistein, a natural isoflavonoid phytoestrogen, has been shown to have anticancer activity by inducing cell cycle arrest at G2M phase as well as apoptosis in various cancer cell lines. In the present study, we showed that treatment with TRAIL in combination with subtoxic concentrations of genistein sensitized U937 human leukemia cells to TRAIL-mediated apoptosis. Combined treatment with genistein and TRAIL effectively activated caspases through Bid truncation (tBid) and down-regulation of cellular caspase-8 (FLICE)-like inhibitory proteinL ($cFLIP_L$). However, the apoptotic effects of co-treatment with genistein and TRAIL were significantly inhibited by specific caspase inhibitors, which demonstrates the important role of caspases in apoptosis induced by genistein and TRAIL. Overall, our results indicate that genistein can potentiate TRAIL-induced apoptosis through down-regulation of $cFLIP_L$ and up-regulation of pro-apoptotic tBid proteins.

• Journal of Acupuncture Research
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• v.17 no.2
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• pp.169-186
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• 2000

To study anti-cancer effect and molecular biological mechanism of bee venom for aqua-acupuncture, the effects of bee venom on cell viability, apoptosis, and cell cycle were analyzed using MTT assay, tryphan blue assay, [3H]thymidine release assay, flow cytometric analysis, activity of caspase-3 protease activity assay, and immunocytometric analysis of PCNA. To explore whether anti-cancer effects of bee venom are associated with the transcriptional control of gene expression, quantitative RT-PCR analysis of apoptosis- and cell cycle-related genes was performed. The obtained results are summarized as follows: 1. The MTT assay demonstrated that cell viability was decreased by bee venom in a dose-dependant manner. 2. Significant induction of apoptosis was identified using tryphan blue assay, [$^3H$]thymidine release assay, and flow cytometric analysis of sub $G_1$ fraction. 3. In analysis of caspase-3 protease activity, the activity had increased significantly, in a dose-dependant manner. 4. Quantitative RT-PCR analysis of the apoptosis-related genes showed that Bcl-2 and $Bcl-X_L$ were down-regulated whereas Bax was up-regulated by bee venom treatment. 5. In flow cytometric analysis of cell cycle and immunocytometric analysis of PCNA expression, cell numbers of $G_1$ phase was increased by a dose-dependant manner. 6. In quantitative RT-PCR analysis of the cell cycle-related genes, p21, p27, and p57 were increased, while Cyclin D1, CDK4, c-Myc, c-Fos, and Histone H3 were decreased. In contrast, there were no remarkable changes in expression levels of CDC2 and c-Jun.

• Journal of the Korean Society of Radiology
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• v.15 no.3
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• pp.391-399
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• 2021

Eu²⁺ doped polyphosphate NaSr(PO₃)₃ blue-emitting phosphors were synthesized by the conventional solid state method in a reductive atmosphere. The phase formation of NaSr(PO₃)₃ phosphors were characterized by using the X-ray powder diffraction (XRD) measurement. The photoluminescence emission and excitation spectra of the NaSr(PO₃)₃:Eu²⁺ phosphor, and decay curves were measured. Under the near-UV excitation, the phosphor exhibits a band emission around 420 nm assigned to the 4f⁶5d→f7(8S^7/2) transition of Eu²⁺. The temperature dependent emission spectra and decay curves were measured to elevate the thermal properties of the Eu²⁺ doped phosphors. The as-prepared NaSr(PO₃)₃:Eu²⁺ phosphors show a strong temperature dependent performance, which can serve as a promising temperature sensor.

• Natural Product Sciences
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• v.11 no.3
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• pp.139-144
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• 2005

Bioflavone quercetin is believed to play an important role preventing bone loss by affecting osteoclastogenesis and regulating many systemic and local factors including hormones and cytokines. This study examined how quercetin acts on tumor necrosis factor-alpha ($TNF-{\alpha}$)-mediated apoptosis in MC3T3-E1 osteoblastic cells. Apoptosis assays revealed the dose-dependent acceleration of quercetin on $TNF-{\alpha}-induced$ apoptosis in MC3T3-E1 cells, which was demonstrated by the increased number of positively stained cells in the trypan blue staining and TUNEL assay, and the migration of many cells to the $sub-G_0/G_1$ phase in flow cytometric analysis. In particular, quercetin treatment alone increased the expression of p53 and p21 proteins in the cells. Consequently, this study showed that quercetin accelerates the $TNF-{\alpha}-induced$ apoptosis in MC3T3-E1 osteoblastic cells.

• Korean Journal of Materials Research
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• v.22 no.2
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• pp.91-96
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• 2012

AC and ZnS modified $TiO_2$ composites (AC/ZnS/$TiO_2$) were prepared using a sol-gel method. The composite obtained was characterized by Brunauer-Emmett-Teller (BET) surface area measurements, X-ray diffraction (XRD), energy dispersive X-ray (EDX) analysis, scanning electron microscope (SEM) analysis, and according to the UV-vis absorption spectra (UV-vis). XRD patterns of the composites showed that the AC/ZnS/$TiO_2$ composites contain a typical single and clear anatase phase. The surface properties as observed by SEM present the characterization of the texture of the AC/ZnS/$TiO_2$ composites, showing a homogenous composition in the particles showing the micro-surface structures and morphology of the composites. The EDX spectra of the elemental identification showed the presence of C and Ti with Zn and S peaks for the AC/ZnS/$TiO_2$ composite. UV-vis patterns of the composites showed that these composites had greater photocatalytic activity under visible light irradiation. A rhodamine B (Rh.B) solution under visible light irradiation was used to determine the photocatalytic activity. The degradation of Rh.B was determined using UV/Vis spectrophotometry. An increase in the photocatalytic activity was observed. From the photocatalytic results, the excellent activity of the Y-fullerene/$TiO_2$ composites for the degradation of methylene blue under visible irradiation could be attributed to an increase in the photo-absorption effect caused by the ZnS and to the cooperative effect of the AC.