• KSBB Journal
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• v.14 no.6
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• pp.665-671
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• 1999

In this study, enhanced production of 10-deacetylbaccatin III(10-DAB), a precursor of taxol in semisynthesis, was investigated in Taxus cuspidata cell suspension cultures. The effects of initial inoculum size and sugar concentration were examined to prove the relationship between the production of 10-DAB and cell growth. The cell growth was found to be stimulated in Schenk and Hildebrandt(SH) medium. The lower the inoculum size as well as initial sugar concentration, the faster the cell growth rate. When the initial sugar concentration was dept low, the production of 10-DAB into medium was increased. By using perfusion culture, continuous cell growth was possible until the end of culture and more than 34.67 g/L of cell concentration could by obtained. This is about 2.5 times higher level than that of control batch culture.

• KSBB Journal
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• v.9 no.2
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• pp.186-190
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• 1994

The content of taxol and related compounds in various tissues of native yews( T. cuspidata var. latifolia) grown in 5 locations of Ullung Island were analyzed. A considerable range of vanation in the content was observed in the needle and bark collected from different trees located at the same area as well as at five different areas. Taxol content was much higher in the needle(0.017% on the dry weight basis) than those in the bark, whereas the content of 10-deacetyl baccatin III(10-DAB III) was slightly higher in the bark(0.073%), regardless of the location of the trees collected. Particuayly, the needle collected from the Hyunpo area, which located in North-west part of Ullung Island, contained the highest level of taxol(0.024%) exceeding the reported level in dried barks of Pacific yew and also somewhat higher level of its Precusor, 10-DAB III(0.049%). These results suggested that the needle of the yew at the Ullung Island could be suitable materials as a renewable source for the mass production of taxol.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.18 no.2 s.117
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• pp.227-232
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• 2007

In this paper, we propose Triple-band antenna, which is practicable for the transmission and the reception of the frequency band used in mobile broadcast and mobile internet. We choose T-DMB(Band-III), DAB(L-Band) for a mobile broadcast and Wibro for a mobile internet. The size of proposal antenna measures $10{\times}74{\times}0.6[mm^3]$. Although being defective in that T-DMB bandwidth is rather narrow, the antenna, considering the reception environment, has an advantage of a realistic possibility of reception in 8 channel($180{\sim}186$ MHz)and 12 channel($206{\sim}210$ MHz) of T-DMB band, being given broadcast services. Also It has gains similar characteristics of ideal dipole antenna in DAB and Wibro band.

• Journal of the Korean Wood Science and Technology
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• v.27 no.3
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• pp.91-98
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• 1999

The content of taxol and related compounds in needle and stem tissues of exotic yews growing in the Chollipo Arboretum which located in the West Sea of Korea were determined by HPLC. A considerable variation in contents of taxol and the related compounds within species and among cultivars were observed. The content of taxol was much higher in the needles than those in the young stem tissues except T. X media cv. Vermuleun, T. baccata cv. Washingtonii, and T. X cuspidata cv. Nana, and the content of 10-deacetyl baccatin III(10-DAB III) was also slightly higher in the needle. The needle of T. cuspidata cv. Nigra collected from April was contained the high amount of taxol(1,027 ${\mu}g$ per g dry weight) and also contained high quantity in 10-DAB III(267 ${\mu}g$ per g dry weight). Concentration of taxol in needle was significantly greater than those of meristemic and ovary tissues, Exotic yews growing at the Chollipo Arboretum containing T. cuspidata cv. Nigra could be suitable materials as a source for the tissue and cell cultures for production of taxol.

• ETRI Journal
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• v.33 no.6
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• pp.969-972
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• 2011

This letter presents a CMOS RF front-end operating in a subthreshold region for low-power Band-III mobile TV applications. The performance and feasibility of the RF front-end are verified by integrating with a low-IF RF tuner fabricated in a 0.13-${\mu}m$ CMOS technology. The RF front-end achieves the measured noise figure of 4.4 dB and a wide gain control range of 68.7 dB with a maximum gain of 54.7 dB. The power consumption of the RF front-end is 13.8 mW from a 1.2 V supply.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.21 no.4
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• pp.443-451
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• 2010

This paper describes a fully integrated CMOS low-IF mobile-TV RF tuner for Band-III T-DMB/DAB applications. All functional blocks such as low noise amplifier, mixers, variable gain amplifiers, channel filter, phase locked loop, voltage controlled oscillator and PLL loop filter are integrated. The gain of LNA can be controlled from -10 dB to +15 dB with 4-step resolutions. This provides a high signal-to-noise ratio and high linearity performance at a certain power level of RF input because LNA has a small gain variance. For further improving the linearity and noise performance we have proposed the RF VGA exploiting Schmoock's technique and the mixer with current bleeding, which injects directly the charges to the transconductance stage. The chip is fabricated in a 0.18 um mixed signal CMOS process. The measured gain range of the receiver is -25~+88 dB, the overall noise figure(NF) is 4.02~5.13 dB over the whole T-DMB band of 174~240 MHz, and the measured IIP3 is +2.3 dBm at low gain mode. The tuner rejects the image signal over maximum 63.4 dB. The power consumption is 54 mW at 1.8 V supply voltage. The chip area is $3.0{\times}2.5mm^2$.

• Proceedings of the Korea Society of Environmental Toocicology Conference
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• 1996.12a
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• pp.61-61
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• 1996

Taxol is used as cancer therapeutic agent. It has been known as weak posotive of chromosome aberration assay in vitro in our previous results (Ryu et al., 1996) and potent clastogens in the mouse bone marrow micronucleus (Tinwell and Ashby, 1994). We performed microgel electrophoresis to determine the effect of taxol and it's precursor 10-deacetyl baccatin III(DAB) on DNA. Microgel electrophoresis is useful, rapid, simple, visual, and sensitive technique for measuring DNA breakage and repair mechanisms in mammalian 근ells. The range of concentration used for taxol were 854, 427, 213.5, 106.8, 53.4 Ug/ml, for DAB 910 ,455, 227.5 U9/ml, Cell viability always exceed 85%. We analyzed the results by using the special software of image analyzer for this comet assay (Komet 3.0). By using this image analyzer software , we can get the result as the tail moment ((mean of tail length - mean of head lengh) x tail%DNA/100). A slight increase in DNA migration was observed for taxol at the concentration of 854 Ug/m4 in the absence of S9 mixture. No increased DNA migration was observed after treatment with DAB.

• Journal of Microbiology and Biotechnology
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• v.19 no.11
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• pp.1342-1347
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• 2009

We have isolated endophytic fungi from the Indian yew tree, Taxus baccata, and then screened for taxol production. Out of the 40 fungal cultures screened, one fungus Gliocladium sp. was found to produce taxol and 10-DABIII (10-deacetyl baccatin III). These compounds were purified by TLC and HPLC and characterized using UV-spectroscopy, ESI-MS, MS/MS, and proton NMR. One liter of Gliocladium sp. culture yielded $10\;{\mu}g$ of taxol and $65\;{\mu}g$ of 10-DABIII. The purified taxol from the fungus showed cytotoxicity towards cancer lines HL-60 (leukemia), A431 (epidermal carcinoma), and MCF-7 (breast cancer).

• Bulletin of the Korean Chemical Society
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• v.30 no.1
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• pp.25-26
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• 2009