著者
滝口 昇
出版者
日本生物工学会
雑誌
生物工学会誌 : seibutsu-kogaku kaishi (ISSN:09193758)
巻号頁・発行日
vol.89, no.12, pp.732-738, 2011-12-25
参考文献数
42
著者
山下 道雄 松田 充功 大畑 暢敬 神田 宗和 檜垣 知臣
出版者
日本生物工学会
雑誌
生物工学会誌 : seibutsu-kogaku kaishi (ISSN:09193758)
巻号頁・発行日
vol.83, no.3, pp.123-131, 2005-03-25
参考文献数
3
被引用文献数
1

In 1989, in the course of our screening for new antifungal antibiotics with cell wall synthesis inhibition activity, FR901379 (WF11899A) was discovered in the culture broth of Coleophoma empetri F-11899. The strain was isolated from a soil sample collected in Iwaki city, Fukushima-prefecture, Japan. Because FR901379 had hemolytic activity, we decided to screen for semi-synthesis derivatives with low toxicity and high antifungal activity and evaluated many derivatives with substituted side chains. We started by using Actinoplanes utahensis to replace the palmitoyl group of FR901379 with other organic acids. After synthesizing several hundred organic acids and making repeated derivatives, we discovered FR131535, which had similar antifungal activity to FR901379 in vitro and in vivo and low hemolytic activity. It was not however selected as a development candidate because of insufficient antifungal activity. In the search for a more potent compound, we hypothesized that a compound with a similar molecular structure to FR131535 might produce a good antifungal drug. We therefore began the screening of Fujisawa's original acylase using a specially devised and effective screening system. After discovering "FR901379 Acylase" produced by Streptomyces sp. No. 6907, we continued with our evaluation of derivatives. We finally selected FK463 as a candidate compound for commercial drug development. In 1990, to establish an industrial manufacturing method for Micafungin (FK463), our laboratories (Fermentation Development Laboratories) commenced the following development research : (1) strain improvement of Coleophoma, (2) screening of "FR901379 Acylase"-producing strains, (3) studies to increase the scale of fermentation of FR901379 and "FR901379 Acylase", (4) determination of effective purification procedures for FR901379, a key intermediate of FR179642 and FK463, and (5) development of a HPLC assay system to measure the amount of objective compounds and impurities. Micafungin (general name, Trade mark : Funguard, Development No. : FK463) was launched in Japan on December 6, 2002. Approval in the USA and EU is pending and expected shortly.
著者
添田 愼介 明石 健志 前田 清 川北 毅
出版者
日本生物工学会
雑誌
生物工学会誌 : seibutsu-kogaku kaishi (ISSN:09193758)
巻号頁・発行日
vol.76, no.9, pp.389-397, 1998-09-25
参考文献数
11
被引用文献数
2

Tacrolimus is an immunosuppressant macrolide isolated from Streptomyces tsukubaensis. It is used clinically to prevent the rejection of tissue transplants. To achieve the industrial production of tacrolimus, development research was aimed at breeding strains that efficiently produce tacrolimus, optimizing the cultivation conditions, determining an effective purification method, and establishing a means of rapid quantitative analysis. The wild-type S. tsukubaensis was sequentially treated with ultra violet light to furnish various types of morphologically altered mutants, from which a desired strain was selected and bred. For the fermentation of the new strain, a cultivation medium was formulated with a low viscosity and resistant to thermo-denaturation on sterilization. In a scale-up study, in which the fermentor size was increased from 30l to 25kl, the productivity of tacrolimus was found to be well reproduced by keeping both the dissolved oxygen and the agitation at low levels during the growth phase of the producing strain. As a result of these procedures, the concentration of tacrolimus in the fermentation broth was increased 300-fold over that obtaind in the early stages of the research with the wild strain. S. tsukubaensis produces many kinds of proteins and oligosacchalides as well as various types of tacrolimus related compounds. To remove these impurities effectively, the cultivation broth was directly extracted with acetone. The extract was successively purified with a high porosity absorbance resin, and acidic and natural silica gel column chromatography, followed by recrystalization in aqueous acetonitrile, to obtain tacrolimus monohydrate. Tacrolimus itself is readily converted to optical and steric isomers in an aqueous solution. When tacrolimus was analyzed by HPLC at lower temperatures, the peaks corresponding to the macrolide were complex because of cis-trans isomerization in the column. The problem was overcome by heating the column to 50℃, when the isomerization rate was so high that the peaks were fused into a single, sharp one. The epimerization ratio was found to depend on the concentration of water in the solution, but the ratio remained constant when a Brij-35 solution used as a diluent. By these procedures, a simple, rapid and reliable analytical method was established. The industrial production of tacrolimus was thus achieved by a combination of fermentation, purification, and analytical investigations.
著者
上野 義栄 平賀 和三 森 義治 小田 耕平
出版者
日本生物工学会
雑誌
生物工学会誌 : seibutsu-kogaku kaishi (ISSN:09193758)
巻号頁・発行日
vol.85, no.3, pp.109-114, 2007
参考文献数
30
被引用文献数
4

古来の発酵法を用いて製造した京漬物,千枚漬けよりγ-アミノ酪酸(GABA)を高生産する乳酸菌が分離され,Lactobacillus sp. L13と同定,命名した.本菌は,増殖にグルタミン酸を要求し,高濃度のグルタミン酸存在下でGABAを高生産した.培養液のpHを酸性(pH5)に維持すると, 800mMのグルタミン酸ナトリウムより81%の変換率で,最大650mM (6.7%)のGABAを生産した.この乳酸菌をスターター菌として使用し,GABAを0.1%含有した千枚漬けを試作した.官能評価の結果,従来の製品よりも風味のすぐれた千枚漬けの製造が可能であることが示された.

1 0 0 0 OA けいじばん

雑誌
生物工学会誌 (ISSN:09193758)
巻号頁・発行日
vol.72, no.6, pp.507-515, 1994-11-25
著者
佐々木 健 岸部 貴 竹野 健次 三上 綾香 原田 敏彦 大田 雅博
出版者
公益社団法人日本生物工学会
雑誌
生物工学会誌 : seibutsu-kogaku kaishi (ISSN:09193758)
巻号頁・発行日
vol.91, no.8, pp.432-446, 2013-08-25

光合成細菌,Rhodobacter sphaeroides SSIを,電磁石で回収可能な多孔質セラミックに固定化して,放射性核種であるU,SrおよびCoと重金属または有害金属のHg,Pb,Cr,CdおよびAsの除去実験を行った.ほぼ100%のU,82%のSr,58%のCoと,ほぼ100%の重金属または有害金属が,2-4日間,人工下水中で好気処理することにより除去された.廃棄ガラスで作製した多孔質セラミックにSSI株を固定化したところ,CsとSrの同時除去が達成された.1トンタンクを用いた屋外実証実験では,ほぼ100%のCsと,62%のSrが,2-3日の処理後に除去されていた,アルギン酸を用いて約2cmのビーズ状に固定化したSSI株を用いて,福島市中の学校の水泳プールの放射性Cs除去を行った.3日の好気処理で水泳プールの底の底質(ヘドロ)中に蓄積された放射性Csの約90%が除染された.このビーズは少なくとも3回は繰り返し使用が可能であった.回収したビーズは,低温(約600℃)で乾燥と灰化を行うと,重量と容量がそれぞれ,99.3%と97.3%に,放射能を大気中にまき散らすことなく減容できた.さらに,福島の放射能汚染された土壌について,乳酸発酵と嫌気消化を前処理として行い,引き続き固定化SSIビーズで追加処理を行ったところ,約19日のSSI株追加処理で放射能汚染土壌の放射能の約70%が除染された.このように,乳酸発酵と嫌気消化と固定化SSI処理を新規に組み合わせることにより,土壌に対する実用的かつ効果的な放射性Csの除染技術が開発された.