...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Applied Microbiology and Biotechnology >Enzymatic (R)-phenylacetylcarbinol production in benzaldehyde emulsions
【24h】

Enzymatic (R)-phenylacetylcarbinol production in benzaldehyde emulsions

机译：苯甲醛乳液中的酶促（R）-苯基乙酰甲醇生产

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

(R)-Phenylacetylcarbinol [(R)-PAC)] is the chiral precursor for the production of the pharmaceuticals ephedrine and pseudoephedrine. Reaction conditions were improved to achieve increased (R)-PAC levels in a simple batch biotransformation of benzaldehyde emulsions and pyruvate, using partially purified pyruvate decarboxylase (PDC) from the filamentous fungus Rhizopus javanicus NRRL 13161 as the catalyst. Lowering the temperature from 23°C to 6°C decreased initial rates but increased final (R)-PAC concentrations. Addition of ethanol, which increases benzaldehyde solubility, was not beneficial for (R)-PAC production. It was established that proton uptake during biotransformation increases the pH above 7 thereby limiting (R)-PAC production. For small-scale studies, biotransformations were buffered with 2–2.5 M MOPS (initial pH 6.5). High concentrations of MOPS as well as some alcohols and KCl stabilised PDC. A balance between PDC and substrate concentrations was determined with regards to (R)-PAC production and yields on enzyme and substrates. R. javanicus PDC (7.4 U/ml) produced 50.6 g/l (337 mM) (R)-PAC in 29 h at 6°C with initial 400 mM benzaldehyde and 600 mM pyruvate. Molar yields on consumed benzaldehyde and pyruvate were 97% and 59%, respectively, with 17% pyruvate degraded and 24% converted into acetaldehyde and acetoin; 43% PDC activity remained, indicating reasonable enzyme stability at high substrate and product concentrations.
机译：（R）-苯基乙酰基甲醇[[R-PAC]]是用于生产麻黄碱和伪麻黄碱的手性前体。使用来自丝状真菌爪哇根霉NRRL 13161的部分纯化的丙酮酸脱羧酶（PDC），通过简单的批量苯甲醛乳液和丙酮酸的生物转化，提高了反应条件，以提高（R）-PAC含量。将温度从23°C降低到6°C降低了初始速率，但增加了最终（R）-PAC浓度。添加乙醇会增加苯甲醛的溶解度，对（R）-PAC生产无益。已经确定，生物转化过程中质子的吸收使pH增加到7以上，从而限制了（R）-PAC的产生。对于小规模研究，生物转化用2-2.5 M MOPS（初始pH 6.5）缓冲。高浓度的MOPS以及一些醇和氯化钾稳定了PDC。关于（R）-PAC的产生以及酶和底物的产率，确定了PDC和底物浓度之间的平衡。爪哇爪哇PDC（7.4 U / ml）在29°C下于6小时内于29小时内产生50.6 g / l（337 mM）（R）-PAC，最初含400 mM苯甲醛和600 mM丙酮酸。消耗的苯甲醛和丙酮酸的摩尔产率分别为97％和59％，其中17％的丙酮酸降解，24％的转化为乙醛和丙酮。保留了43％的PDC活性，表明在高底物和产物浓度下酶具有合理的稳定性。

著录项

  • 来源
    《Applied Microbiology and Biotechnology》 |2002年第2期|94-100|共7页
  • 作者

    B. Rosche; N. Leksawasdi; V. Sandford; M. Breuer; B. Hauer; P. Rogers;

  • 作者单位

    School of Biotechnology and Biomolecular Sciences University of New South Wales Sydney NSW 2052 Australia;

    School of Biotechnology and Biomolecular Sciences University of New South Wales Sydney NSW 2052 Australia;

    School of Biotechnology and Biomolecular Sciences University of New South Wales Sydney NSW 2052 Australia;

    BASF-AG Hauptlaboratorium 67056 Ludwigshafen Germany;

    BASF-AG Hauptlaboratorium 67056 Ludwigshafen Germany;

    School of Biotechnology and Biomolecular Sciences University of New South Wales Sydney NSW 2052 Australia;

  • 收录信息
  • 原文格式 PDF
  • 正文语种 eng
  • 中图分类
  • 关键词

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号