ISSN:0009-286X    

DOI:10.1002/cite.330640602

出版商:WILEY‐VCH Verlag    

年代:1992

数据来源: WILEY

摘要:

AbstractAcetone‐butanol fermentation: basis of a modern biotechnological process?Acetone‐butanol fermentation was performed on a large industrial scale for about forty years. After the Second World War it was unable to compete with petrochemical processes and renewed interest in this fermentation has developed only during the last decade. It has led to a vast increase of our knowledge of the biochemistry of acetone‐butanol formation and of the genetics of the producing organism,Clostridium acetobutylicum.Considerable progress was also made in defining optimal fermentation conditions. However, the biotechnological process is not yet economically feasible, primarily because low final product concentrations engender high product recovery

ISSN:0009-286X    

DOI:10.1002/cite.330640603

出版商:WILEY‐VCH Verlag    

年代:1992

数据来源: WILEY

ISSN:0009-286X    

DOI:10.1002/cite.330640604

出版商:WILEY‐VCH Verlag    

年代:1992

数据来源: WILEY

摘要:

AbstractContinuous processes with soluble enzymes.This paper surveys the use of continuously operating enzyme‐membrane reactors with enforced flow where the retention of soluble enzymes in the reaction vessel is achieved by means of an ultrafiltration membrane. This technique has been commercialized in the acylase process for the synthesis ofL‐amino acids on a 200 ton/year level. It is especially useful for the application of multi‐enzyme systems with cofactor regeneration. The synthesis ofL‐tert‐leucine from the corresponding α‐keto acid has been achieved on a kilogram scale. Coenzymes coupled to water soluble polymers are retained in the membrane‐reactor together with the enzymes. Use of suitable conditions prevents loss of enzyme and coenzyme by passage through the membrane or by deactivation. Therefore the costs of enzymes and coenzymes are no longer limitations for economic processes. In the continuously operating enzyme‐membrane reactor regeneration of the coenzyme up to 600 000 times was achieved. In continuous peptide synthesis space‐time yields of 25 kg/(l d) were obtained. To suppress side reactions very high catalyst concentrations are possible, yielding residence

ISSN:0009-286X    

DOI:10.1002/cite.330640605

出版商:WILEY‐VCH Verlag    

年代:1992

数据来源: WILEY

ISSN:0009-286X    

DOI:10.1002/cite.330640606

出版商:WILEY‐VCH Verlag    

年代:1992

数据来源: WILEY

摘要:

AbstractOptical sensors for bioprocess control.Bioprocess techniques are an important field in biotechnology. To run processes with high yields of products, to ensure product quality and for process optimization it is essential to acquire relevant process and control parameters quickly with high reliability. Therefore, various types of sensors are used; recently, beside chemosensors, new emphasis has been placed on biosensors for bioprocess control. At the same time optical transducers are gaining in significance. One reason for the increasing interest in optical sensors is the ready availability of fiber optic technologies. The combination of sensor technologies with fiber optics offers many possibilities due to miniaturisation and remote control and therefore meets the special requirements of bioprocess techniques. This review introduces various classes of optical chemo‐ and biosensors for bioprocess contro

ISSN:0009-286X    

DOI:10.1002/cite.330640607

出版商:WILEY‐VCH Verlag    

年代:1992

数据来源: WILEY

摘要:

AbstractMicrobial sensors based on respiration measurements.Microbial sensors based on the direct contact of microbe and a transducer convert the chemical composition of the sample into a quantitative electrical signal. They are useful for the determination of a wide range of substrates but also of “group effects” for bioprocess control and environmental protection. Starting from the physiological fundamentals – including various ways of influencing sensor performance ‐ this paper reviews the present state of the development of microbial sensors. Different sensor types developed by the authors's group are pr

ISSN:0009-286X    

DOI:10.1002/cite.330640608

出版商:WILEY‐VCH Verlag    

年代:1992

数据来源: WILEY

摘要:

AbstractQuality assurance in process development.Important decisions pertaining to quality assurance in the chemical industry are already made during process development for new products and improvement of existing processes. This article describes new methods for achieving quality assurance in various phases of process development, both for the process itself and for the desired products. Examples from process engineering with fluids and solids serve to demonstrate the contributions of process engineers to the development of stable and robust processes with regard to quality assurance.

ISSN:0009-286X    

DOI:10.1002/cite.330640609

出版商:WILEY‐VCH Verlag    

年代:1992

数据来源: WILEY

ISSN:0009-286X    

DOI:10.1002/cite.330640610

出版商:WILEY‐VCH Verlag    

年代:1992

数据来源: WILEY

ISSN:0009-286X    

DOI:10.1002/cite.330640611

出版商:WILEY‐VCH Verlag    

年代:1992

数据来源: WILEY