• Title/Summary/Keyword: PO/$Bi_2$$O_3$

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The mechanism of Bi$_{0.5}Pb_3Sr_2Ca_2CuO_{\delta}$ and (Ca,Sr)$_2$(BiPb)O$_4$ phase as a flux-pinning center in (Bi,Pb)$_2Sr_2Ca_2CuO_{10}$ superconductor ((Bi,Pb)$_2Sr_2Ca_2CuO_{10}$ 초전도체에l서 flux-pinning center로서 Bi$_{0.5}Pb_3Sr_2Ca_2CuO_{\delta}$ 및 (Ca,Sr)$_2$(BiPb)O$_4$ 상의도입 기구)

  • Chung, Jun-Ki;Kim, Cheol-Jin;Lee, Sang-Hee;Yoo, Jae-Moo;Kim, Hae-Doo;Koh, Jae-Woong
    • 한국초전도학회:학술대회논문집
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    • v.9
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    • pp.300-304
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    • 1999
  • To tap the feasibility of exploiting the 2$^{nd}$ phases as flux-pinning centers in the (Bi,Pb)$_2Sr_2Ca_2CuO_{10}$ superconductor, the size and the distribution of the precipitates have been controlled by changing reaction temperature and time, oxygen partial pressure Po$_2$ and annealing condition. Various annealing heat treatments were also conducted on the as-received 61 filament Bi-2223 tapes with Bi$_{1.8}Pb_{0.4}Sr_2Ca_{2.2}Cu_3O_8$ starting composition and annealed specimen were analyzed with XRD, SEM, EDS and TEM.. The grain size of (Ca,Sr)$_2$(BiPb)O$_4$ or Bi$_{0.5}Pb_3Sr_2Ca_2CuO_{\delta}$ was controllable by optimizing the heat treatment condition and critical current density (J$_c$) showed dependence on the size of the 2$^{nd}$ phases.

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R-T characteristic of Bi2212 Epitaxial thin films by growth in MgO(100) substrate (MgO(100)기판에 성장시킨 Bi2212 에피택셜 박막의 R-T특성)

  • Yang, Seung-Ho;Lim, Jung-Kwan;Park, Yong-Pil
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2006.06a
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    • pp.537-538
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    • 2006
  • BSCCO thin films have been fabricated by epitaxy growth at an ultra-low growth rate. The growth rates of the films was set in the region from 0.17 to 0.27 nm/min. MgO(100) was used as a substrate. In order to appreciate stable existing region of Bi 2212 phase with temperature and ozone pressure, the substrate temperature was varied between 650 and $720^{\circ}C$ and the highly condensed ozone gas pressure ($PO_3$) in vacuum chamber was varied between $2.0{\times}10^{-6}$ and $2.3{\times}10^{-5}\;Torr$.

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Superconducting Characteristics of Bi Thin Films Fabricated by Ion Beam Sputtering (이온빔 스퍼터법으로 제작한 Bi 박막의 초전도 특성)

  • 이희갑;박용필;오금곤
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2000.07a
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    • pp.222-225
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    • 2000
  • BSCCO thin films have been fabricated by co-deposition at an ultralow growth rate using ion beam sputtering(IBS) method. Bi 2212 phase appeared in the temperature range of 750 and $795^{\circ}C$ and single phase of Bi 2201 existed in the lower region than $785^{\circ}C$. Whereas, $Po_3$ dependance on structural formation was scarcely observed regardless of the pressure variation. And high quality of c-axis oriented Bi 2212 thin film with $T_c$ (onset) of about 90 K and $T_c$(zero) of about 45 K is obtained. Only a smd amount of CuO in some films was observed as impurity, and no impurity phase such as $CaCuO_2$ was observed in d of the obtained films.

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Analysis of Stacking-Fault Proportion on the Mixed Phase of the $Bi_2Sr_2Ca_{n-1}Cu_nO_x$(n=0, 1, 2) Superconducting Thin Films ($Bi_2Sr_2Ca_{n-1}Cu_nO_x$(n=0, 1, 2) 초전도 박막의 혼합상에 대한 고용비 해석)

  • Yang, Seung-Ho;Lee, Ho-Shik;Park, Yong-Pil
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2007.06a
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    • pp.486-487
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    • 2007
  • $Bi_2Sr_2Ca_{n-1}Cu_nO_x$(n=0, 1, 2) thin films have been fabricated by co-deposition at an ultra-low growth rate using ion beam sputtering(IBS) method. The growth rates of the films was set in the region from 0.17 to 0.27 nm/min. MgO(100) was used as a substrate. In order to appreciate stable existing region of Bi 2212 phase with temperature and ozone pressure, the substrate temperature was between 655 and $820^{\circ}C$ and the highly condensed ozone gas pressure in vacuum chamber was varied between $2{\times}10^{-6}{\sim}4{\times}10^{-5}$ Torr. Bi 2212 phase appeared in the temperature range of 750 and $795^{\circ}C$ and single phase of Bi 2201 existed in the lower region than $785^{\circ}C$. Whereas, $PO_3$ dependance on structural formation was scarcely observed regardless of the pressure variation.

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Study on the deposition Characteristics of Bi Thin Film (Bi 박막의 성막 특성에 관한 연구)

  • Yang, Dong-Bok;Park, Yong-Pil;Lee, Hee-Kab
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2003.05d
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    • pp.61-64
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    • 2003
  • This paper presents Bi thin films have been fabricated by atomic layer-by-layer deposition and co-deposition at an IBS method. The growth rates of the films was set in the region from 0.17 to 0.27 nm/min. Mg(100) was used as a substrate. In order to appreciate stable existing region of Bi 2212 phase with temperature and ozone pressure, the substrate temperature was varied between 655 and $820^{\circ}C$ and the highly condensed ozone gas pressure$(PO_3)$ in vacuum chamber was varied between $2.0{\times}10^{-6}$ and $2.3{\times}10^{-5}$ Torr. Bi 2212 phase appeared in the temperature range of 750 and $795^{\circ}C$ and single phase of Bi 2201 existed in the lower region than $785^{\circ}C$. Whereas, $O_3$ dependance on structural formation was scarcely observed regardless of the pressure variation. And high quality of c-axis oriented Bi 2212 thin film with $T_c$(onset) of about 90 K and $T_c$(zero) of about 45 K is obtained. Only a small amount of CuO in some films was observed as impurity, and no impurity phase such as $CaCuO_2$ was observed in all of the obtained films.

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Oxidative Dehydrogenation of 1-butene over BiFe0.65MoP0.1 Catalyst: Effect of Phosphorous Precursors (BiFe0.65MoP0.1 촉매 상에서 1-부텐의 산화탈수소화 반응 : 인 전구체의 영향)

  • Park, Jung-Hyun;Youn, Hyun Ki;Shin, Chae-Ho
    • Korean Chemical Engineering Research
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    • v.53 no.6
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    • pp.824-830
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    • 2015
  • The influence of phosphorous precursors, $NH_4H_2PO_4$, $(NH_4)_2HPO_4$, $H_3PO_4$, $(C_2H_5)_3PO_4$, and $P_2O_5$, on the catalytic performance of the $BiFe_{0.65}MoP_{0.1}$ catalysts in the oxidative dehydrogenation of 1-butene to 1,3-butadiene was studied. The catalysts were characterized by XRD, $N_2$-sorption, ICP, SEM and TPRO analyses. It was not observed big difference on the physical properties of catalysts in accordance with used different phosphorous precursors, however, the catalytic performance was largely depended on the nature of the phosphorous precursors. Of various precursors, the $BiFe_{0.65}MoP_{0.1}$ oxide catalyst, which was prepared from a phosphoric acid precursor, showed the best catalytic performance. Conversion and yield to butadiene of the catalyst showed 79.5% and 67.7%, respectively, after 14 h on stream. The cation of phosphorous precursors was speculated to affect the lattice structure of the catalysts during catalyst preparation and this difference was influenced on the re-oxidation ability of the catalysts. Based on the results of TPRO, it was proposed that the catalytic performance could be correlated with re-oxidation ability of the catalysts.

Fabrication of Bi-2223 high-Tc superconducting current lead (Bi-2223 고온초전도 전류리드의 제조)

  • Ha, D.W.;Oh, S.S.;Ryu, K.S.;Chang, H.M.
    • Proceedings of the KIEE Conference
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    • 1996.07c
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    • pp.1660-1662
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    • 1996
  • Superconducting current lead is one of the promising applications of the oxide high-Tc superconductors, because they have the advantage of decreasing heat conduction to low temperature region, comparing with a conventional cooper alloy lead. High critical current density is a key factor for the applications such as current lead. $(Bi,Pb)_{2}Sr_{2}Ca_{2}Cu_{3}O_{x}$ high Tc superconductor hase been investigated in terms of critical current density. Bi-2223 superconducting current lead made by CIP and solid state sintering process. Bi-2223 current lead that heat treated at $836\;^{\circ}C$ for 240 h in 1/13 $PO_2$ had over $500\;A/cm^2$ of critical current density at 77K. We knew that the superconducting properties of tube type current leads were better than rods type of them. And we investigated the relation of Bi-2223 formation and heat treatment condition by XRD and SEM analysis.

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The recent essay of Bijeung - Study of III- (비증(痺證)에 대(對)한 최근(最近)의 제가학설(諸家學說) 연구(硏究) - 《비증전집(痺證專輯)》 에 대(對)한 연구(硏究) III -)

  • Yang, Tae-Hoon;Oh, Min-Suk
    • Journal of Haehwa Medicine
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    • v.9 no.1
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    • pp.513-545
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    • 2000
  • I. Introduction Bi(痺) means blocking. It can reach at the joints or muscles or whole body and make pains. Numbness and movement disorders. BiJeung can be devided into SilBi and HeoBi. In SilBi there are PungHanSeupBi, YeolBi and WanBi. In HeoBi, there are GiHyeolHeoBi, EumHeoBi and YangHeoBi. The common principle for the treatment of BiJeung is devision of the chronic stage and the acute stage. In the acute stage, BiJeung is usually cured easily but in the chronic stage, it is difficult. In the terminal stage, BiJeung can reach at the internal organs. BiJeung is one kind of symptoms making muscles, bones and jonts feel pain, numbness or edema. For example it can be gout or SLE etc. Many famous doctors studied medical science by their fathers or teachers. So the history of medical science is long. So I studied ${\ll}Bijeungjujip{\gg}$. II. Final Decision 1. BanSuMun(斑秀文) thought that BiJeung can be cured by blocking of blood stream. So he insisted that the important thing to cure BiJeung is to improve the blood stream. He usually used DangGuiSaYeokTang(當歸四逆湯), DangGuiJakYakSanHapORyeongSan, DoHong-SaMulTang(桃紅四物湯), SaMyoSanHapHeuiDongTang and HwangGiGyeJiOMulTang. 2. JangGeonBu(張健夫) focused on soothing muscles and improving blood seam. So he used many herbs like WiRyeongSeon(威靈仙), GangHwal(羌活), DokHwal(獨活), WooSeul(牛膝), etc. Especially he pasted wastes of the boiled herbs. 3. OSeongNong(吳聖農) introduced four rules to treat arthritis. So he usually used SeoGak-SanGaGam(犀角散加減), BoYanHwanOTang(補陽還五湯), ODuTang(烏頭湯), HwangGiGyeJiOMulTang. 4. GongJiSin thought disk hernia as one kind of BiJeung. And he said that Pung can hurt upper limbs and Seup can hurt lower limbs. He used to use GyeJiJakYakJiMoTang(桂枝芍藥知母湯). 5. LoJiJeong(路志正) introduced four principles to treat BiJeung. He used BangPungTang(防風湯), DaeJinGuTang) for PungBi(風痺), OPaeTang(烏貝湯) for HanBi(寒痺), YukGunJaTang(六君子湯) for SeupBi(濕痺) and SaMyoTang(四妙湯), SeonBiTang(宣痺湯), BaekHoGaGyeTang(白虎加桂湯) for YeolBi(熱痺). 6. GangChunHwa(姜春華) discussed herbs. He said SaengJiHwang(生地黃) is effective for PungSeupBi and WiRyungSun(威靈仙) is effective for the joints pain. He usually used SipJeonDaeBoTang(十全大補湯), DangGuiDaeBoTang(當歸大補湯), YoukGunJaTang(六君子湯) and YukMiJiHwanTang(六味地黃湯). 7. DongGeonHwa(董建華) said that the most important thing to treat BiJeung is how to use herbs. He usually used CheonO(川烏), MaHwang(麻黃) for HanBi, SeoGak(犀角) for YeolBi, BiHae) or JamSa(蠶沙) for SeupBi, SukJiHwang(熟地黃) or Vertebrae of Pigs for improving the function of kidney and liver, deer horn or DuChung(杜沖) for improving strength of body and HwangGi(黃?) or OGaPi(五加皮) for improving the function of heart. 8. YiSuSan(李壽山) devided BiJeung into two types(PungHanSeupBi, PungYeolSeupBi). And he used GyeJiJakYakJiMoTang(桂枝芍藥知母湯) for the treatment of gout. And he liked to use HwanGiGyeJiOMulTangHapSinGiHwan 枝五物湯合腎氣丸) for the treat ment of WanBi(頑痺). 9. AnDukHyeong(顔德馨) made YongMaJeongTongDan(龍馬定痛丹)-(MaJeonJa(馬錢子) 30g, JiJaChung 3g, JiRyong(地龍) 3g, JeonGal(全蝎) 3g, JuSa(朱砂) 0.3g) 10. JangBaekYou(張伯臾) devided BiJeung into YeolBi and HanBi. And he focused on improving blood stream. 11. JinMuO(陳茂梧) introduced anti-wind and dampness prescription(HoJangGeun(虎杖根) 15g, CheonChoGeun 15g, SangGiSaeng(桑寄生) 15g, JamSa(蠶絲) 15g, JeMaJeonJa(制馬錢子) 3g). 12. YiChongBo(李總甫) explained basic prescriptions to treat BiJeung. He used SinJeongChuBiEum(新定推痺陰) for HaengBi(行痺), SinJeongHwaBiSan(新定化痺散) for TongBi(痛痺), SinJeongGaeBiTang(新定開痺湯) for ChakBi(着痺), SinJeongCheongBiEum(新定淸痺飮) for SeupYeolBi(濕熱痺), SinRyeokTang(腎瀝湯) for PoBi(胞痺), ORyeongSan for BuBi(腑痺), OBiTang(五痺湯) for JangBi(臟痺), SinChakTang(腎着湯) for SingChakByeong(腎着病). 13. HwangJeonGeuk(黃傳克) used SaMu1SaDeungHapJe(四物四藤合制) for the treatment of a acute arthritis, PalJinHpPalDeungTang(八珍合八藤湯) or BuGyeJiHwangTangHapTaDeungTang(附桂地黃湯合四藤湯) for the chronic stage and ByeolGapJeungAekTongRakEum(鱉甲增液通絡飮) for EumHeo(陰虛) 14. GaYeo(柯與參) used HwalRakJiTongTang(活絡止痛湯) for shoulder ache, SoJongJinTongHwalRakTank(消腫鎭痛活絡湯) for YeolBi(熱痺), LiGwanJeolTang(利關節湯) for ChakBi(着痺), SinBiTang(腎痺湯) for SinBi(腎痺) and SamGyoBoSinHwan(三膠補腎丸) for back ache. 15. JangGilJin(蔣길塵) liked to use hot-character herbs and insects. And he used SeoGeunLipAnTang(舒筋立安湯) as basic prescription. 16. RyuJangGeol(留章杰) used GuMiGangHwalTang(九味羌活湯) and BangPungTang(防風湯) at the acute stage, ODuTang(烏頭湯) or GyeJiJakYakJiMoTang(桂枝芍藥知母湯) for HanBi of internal organs, YangHwaHaeEungTang(陽和解凝湯) for HanBi, DokHwalGiSaengTang(獨活寄生湯), EuiYiInTang(薏苡仁湯) for SeupBi, YukGunJaTang(六君子湯) for GiHeoBi(氣虛痺) and SeongYouTang(聖兪湯) for HyeolHeoBi(血虛痺). 17. YangYuHak(楊有鶴) liked to use SoGyeongHwalHyelTang(疏經活血湯) and he would rather use DoIn(桃仁), HongHwa(紅花), DangGui(當歸), CheonGung(川芎) than insects. 18. SaHongDo(史鴻濤) made RyuPungSeupTang(類風濕湯)-((HwangGi 200g, JinGu 20g, BangGi(防己) 15g, HongHwa(紅花) 15g, DoIn(桃仁) 15g, CheongPungDeung(靑風藤) 20g, JiRyong(地龍) 15g, GyeJi(桂枝) 15g, WoSeul(牛膝) 15g, CheonSanGap(穿山甲) 15g, BaekJi(白芷) 15g, BaekSeonPi(白鮮皮) 15g, GamCho(甘草) 15g).

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Surface Protection Obtained by Anodic Oxidation of New Ti-Ta-Zr Alloy

  • Vasilescu, C.;Drob, S.I.;Calderon Moreno, J.M.;Drob, P.;Popa, M.;Vasilescu, E.
    • Corrosion Science and Technology
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    • v.17 no.2
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    • pp.45-53
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    • 2018
  • A new 80Ti-15Ta-5Zr wt% alloy surface was protected by anodic oxidation in phosphoric acid solution. The protective oxide layer (TiO2, ZrO2 and Ta suboxides and thickness of 15.5 nm) incorporated $PO{_4}^{3-}$ ions from the solution, according to high resolution XPS spectra. The AFM analysis determined a high roughness with SEM detected pores (20 - 50 nm). The electrochemical studies of bare and anodically oxidized Ti-15Ta-5Zr alloy in Carter-Brugirard saliva of different pH values and saliva with 0.05M NaF, pointed to a nobler surface for the protected alloy, with a thicker electrodeposited oxide layer acting as a barrier against aggressive ions. The oxidized alloy significantly decreased corrosion current densities and total quantity of ions released into the oral environment in comparison with the bare one, at higher polarisation resistance and protective capacity of the electrodeposited layer. The impedance data revealed a bi-layered oxidation film formed by: a dense, compact, barrier layer in contact with the metallic substrate, decreasing the potential gradient across the metal/oxide layer/solution interface, reducing the anodic dissolution and a more permissive, porous layer in contact with the electrolyte. The open circuit potential for protected alloy shifted to nobler values, with thickening of the oxidation film signifying long-term protection.

Sesquiterpenoids Bioconversion Analysis by Wood Rot Fungi

  • Lee, Su-Yeon;Ryu, Sun-Hwa;Choi, In-Gyu;Kim, Myungkil
    • 한국균학회소식:학술대회논문집
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    • 2016.05a
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    • pp.19-20
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    • 2016
  • Sesquiterpenoids are defined as $C_{15}$ compounds derived from farnesyl pyrophosphate (FPP), and their complex structures are found in the tissue of many diverse plants (Degenhardt et al. 2009). FPP's long chain length and additional double bond enables its conversion to a huge range of mono-, di-, and tri-cyclic structures. A number of cyclic sesquiterpenes with alcohol, aldehyde, and ketone derivatives have key biological and medicinal properties (Fraga 1999). Fungi, such as the wood-rotting Polyporus brumalis, are excellent sources of pharmaceutically interesting natural products such as sesquiterpenoids. In this study, we investigated the biosynthesis of P. brumalis sesquiterpenoids on modified medium. Fungal suspensions of 11 white rot species were inoculated in modified medium containing $C_6H_{12}O_6$, $C_4H_{12}N_2O_6$, $KH_2PO_4$, $MgSO_4$, and $CaCl_2$ for 20 days. Cultivation was stopped by solvent extraction via separation of the mycelium. The metabolites were identified as follows: propionic acid (1), mevalonic acid lactone (2), ${\beta}$-eudesmane (3), and ${\beta}$-eudesmol (4), respectively (Figure 1). The main peaks of ${\beta}$-eudesmane and ${\beta}$-eudesmol, which were indicative of sesquiterpene structures, were consistently detected for 5, 7, 12, and 15 days These results demonstrated the existence of terpene metabolism in the mycelium of P. brumalis. Polyporus spp. are known to generate flavor components such as methyl 2,4-dihydroxy-3,6-dimethyl benzoate; 2-hydroxy-4-methoxy-6-methyl benzoic acid; 3-hydroxy-5-methyl phenol; and 3-methoxy-2,5-dimethyl phenol in submerged cultures (Hoffmann and Esser 1978). Drimanes of sesquiterpenes were reported as metabolites from P. arcularius and shown to exhibit antimicrobial activity against Gram-positive bacteria such as Staphylococcus aureus (Fleck et al. 1996). The main metabolites of P. brumalis, ${\beta}$-Eudesmol and ${\beta}$-eudesmane, were categorized as eudesmane-type sesquiterpene structures. The eudesmane skeleton could be biosynthesized from FPP-derived IPP, and approximately 1,000 structures have been identified in plants as essential oils. The biosynthesis of eudesmol from P. brumalis may thus be an important tool for the production of useful natural compounds as presumed from its identified potent bioactivity in plants. Essential oils comprising eudesmane-type sesquiterpenoids have been previously and extensively researched (Wu et al. 2006). ${\beta}$-Eudesmol is a well-known and important eudesmane alcohol with an anticholinergic effect in the vascular endothelium (Tsuneki et al. 2005). Additionally, recent studies demonstrated that ${\beta}$-eudesmol acts as a channel blocker for nicotinic acetylcholine receptors at the neuromuscular junction, and it can inhibit angiogenesis in vitro and in vivo by blocking the mitogen-activated protein kinase (MAPK) signaling pathway (Seo et al. 2011). Variation of nutrients was conducted to determine an optimum condition for the biosynthesis of sesquiterpenes by P. brumalis. Genes encoding terpene synthases, which are crucial to the terpene synthesis pathway, generally respond to environmental factors such as pH, temperature, and available nutrients (Hoffmeister and Keller 2007, Yu and Keller 2005). Calvo et al. described the effect of major nutrients, carbon and nitrogen, on the synthesis of secondary metabolites (Calvo et al. 2002). P. brumalis did not prefer to synthesize sesquiterpenes under all growth conditions. Results of differences in metabolites observed in P. brumalis grown in PDB and modified medium highlighted the potential effect inorganic sources such as $C_4H_{12}N_2O_6$, $KH_2PO_4$, $MgSO_4$, and $CaCl_2$ on sesquiterpene synthesis. ${\beta}$-eudesmol was apparent during cultivation except for when P. brumalis was grown on $MgSO_4$-free medium. These results demonstrated that $MgSO_4$ can specifically control the biosynthesis of ${\beta}$-eudesmol. Magnesium has been reported as a cofactor that binds to sesquiterpene synthase (Agger et al. 2008). Specifically, the $Mg^{2+}$ ions bind to two conserved metal-binding motifs. These metal ions complex to the substrate pyrophosphate, thereby promoting the ionization of the leaving groups of FPP and resulting in the generation of a highly reactive allylic cation. Effect of magnesium source on the sesquiterpene biosynthesis was also identified via analysis of the concentration of total carbohydrates. Our current study offered further insight that fungal sesquiterpene biosynthesis can be controlled by nutrients. To profile the metabolites of P. brumalis, the cultures were extracted based on the growth curve. Despite metabolites produced during mycelia growth, there was difficulty in detecting significant changes in metabolite production, especially those at low concentrations. These compounds may be of interest in understanding their synthetic mechanisms in P. brumalis. The synthesis of terpene compounds began during the growth phase at day 9. Sesquiterpene synthesis occurred after growth was complete. At day 9, drimenol, farnesol, and mevalonic lactone (or mevalonic acid lactone) were identified. Mevalonic acid lactone is the precursor of the mevalonic pathway, and particularly, it is a precursor for a number of biologically important lipids, including cholesterol hormones (Buckley et al. 2002). Farnesol is the precursor of sesquiterpenoids. Drimenol compounds, bi-cyclic-sesquiterpene alcohols, can be synthesized from trans-trans farnesol via cyclization and rearrangement (Polovinka et al. 1994). They have also been identified in the basidiomycota Lentinus lepideus as secondary metabolites. After 12 days in the growth phase, ${\beta}$-elemene caryophyllene, ${\delta}$-cadiene, and eudesmane were detected with ${\beta}$-eudesmol. The data showed the synthesis of sesquiterpene hydrocarbons with bi-cyclic structures. These compounds can be synthesized from FPP by cyclization. Cyclic terpenoids are synthesized through the formation of a carbon skeleton from linear precursors by terpene cyclase, which is followed by chemical modification by oxidation, reduction, methylation, etc. Sesquiterpene cyclase is a key branch-point enzyme that catalyzes the complex intermolecular cyclization of the linear prenyl diphosphate into cyclic hydrocarbons (Toyomasu et al. 2007). After 20 days in stationary phase, the oxygenated structures eudesmol, elemol, and caryophyllene oxide were detected. Thus, after growth, sesquiterpenes were identified. Per these results, we showed that terpene metabolism in wood-rotting fungi occurs in the stationary phase. We also showed that such metabolism can be controlled by magnesium supplementation in the growth medium. In conclusion, we identified P. brumalis as a wood-rotting fungus that can produce sesquiterpenes. To mechanistically understand eudesmane-type sesquiterpene biosynthesis in P. brumalis, further research into the genes regulating the dynamics of such biosynthesis is warranted.

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