摘要:

AbstractPhotosynthetic ATP regeneration was measured in open reactors using immobilized Chromatophores fromRhodopseudomonas capsulata. The influence of several factors on both initial and long‐term ADP photophosphorylation was studied. The effect of phosphate salts and of bovine serum albumin on the organelle activity yield was studied. Photophosphorylation was initiated either with ADP or regenerated ATP and the roles of these nucleotides were compared. Different photoreactor configurations were tested for the production of a phosphorylated compound and a flat reactor selected. The presence of inorganic pyrophosphate in the reaction medium was shown to improve the synthesis of ATP 1.4 times. Using the optimal conditions described here, the total G‐6P production was 50‐fold higher than in batch rea

ISSN:0006-3592    

DOI:10.1002/bit.260290112

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1987

数据来源: WILEY

摘要:

AbstractThe effect of dissolved oxygen shock on the stability of recombinantEscherichia colicells containing plasmid pKN401 was investigated. The recombinant cells were stable in control batch experiments in media with and without ampicillin. However, these recombinant cells were highly unstable under conditions where a dissolved oxygen shock was induced. The results have implications for design of aerated reactors for recombinant cells.

ISSN:0006-3592    

DOI:10.1002/bit.260290113

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1987

数据来源: WILEY

摘要:

AbstractThe cellulase activity in cell‐free broths from the thermophilic, ethanol‐producing anaerobic bacteriumClostridium thermocellumis examined on both dilute‐acid‐pretreated mixed hardwood (90% maple, 10% birch) and Avicel. Experiments were conductedin vitroin order to distinguish properties of the cellulase from properties of the organism and to evaluate the effectiveness ofC. thermocellum cellulasein the hydrolysis of a naturally occurring, lignin‐containing substrate. The results obtained establish that essentially quantitative hydrolysis of cellulose from pretreated mixed hardwood is possible using this enzyme system. Pretreatment with 1% H2SO4and a 9‐s residence time at 220, 210, 200, and 180°C allowed yields after enzymatic hydrolysis (percentage of glucan solubilized/ glucan potentially solubilized) of 97.8, 86.1, 82.0, and 34.6%, respectively. Enzymatic hydrolysis of mixed hardwood with no pretreatment resulted in a yield of 10.1%. Hydrolysis yields of>95% were obtained from ∼0.6 g/L mixed hardwood pretreated at 220°C in 7 h at broth strengths of 60 and 80% (v/v) and in approximately 48 h with 33% broth. Hydrolysis of pretreated mixed hardwood is compared to hydrolysis of Avicel, a pure microcrystalline cellulose studied previously. The initial rate of Avicel hydrolysis saturates with respect to enzyme, whereas the initial rate of hydrolysis of pretreated wood is proportional to the amount of enzyme present. Initial hydrolysis rates for pretreated wood and Avicel at 0.6 g/L are greater for wood at low broth dilutions (1.25: 1 to 5 :1) by up to 2.7‐fold and greater for Avicel at high broth dilutions (5 : 1 to 50 : 1) by up to 4.3‐fold. Maximum rates of hydrolysis are achieved at<2 g substrate/L for both pretreated wood and Avicel. The substrate concentration at one‐half the maximum observed rate forC. thermocellumbroths is smaller for pretreated mixed hardwood than for Avicel and decreases with increasing broth dilution for both substrates. An initial activity per volume broth of approximately 11 μmol soluble glucose equivalent produced/L broth/min is observed for mixed hardwood pretreated at 220°C and for Avicel at high broth dilutions; the initial activity per volume broth for Avicel is lower at low broth dilutions. The results indicate that pretreated wood is hydrolyzed at rates comparable to Avicel under many conditions and at rates significantly faster than Avicel u

ISSN:0006-3592    

DOI:10.1002/bit.260290114

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1987

数据来源: WILEY

摘要:

AbstractA tube rheometer system has been constructed for aseptic study of the rheology and fundamental flow properties of mycelial fermentation fluids. The rheometer consists of a U‐formed tube circuit starting and ending inside the fermentor. The mash is pumped through the tubes with a lobe rotor pump. The flow is measured by an electromagnetic flow meter. Pressure drops have been measured with a system of differential membrane transducers for different flow rates. The rheometer system was tested with Newtonian and non‐Newtonian flu

ISSN:0006-3592    

DOI:10.1002/bit.260290115

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1987

数据来源: WILEY

摘要:

AbstractThe flow behavior of a penicillin mash has been investigated with a tube rheometer and compared with rotational viscometer observations. In the low‐shear regions plug flow and breakdown of the plug have been studied. For turbulent flow turbulence damping was demonstrated. The Theological development during the fermentation was followed. At low deformation rates the pressure drop increased during the fermentation. In turbulent regions the opposite tendency was observed. The possible underlying flow mechanisms are discussed, and the influence of a number of physical parameters have been investigate

ISSN:0006-3592    

DOI:10.1002/bit.260290116

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1987

数据来源: WILEY

摘要:

AbstractHydrodynamic phenomena in microcarrier cultures are investigated with regard to the development of improved reactor designs for large‐scale operations. New concepts and theoretical models that describe new data as well as previously published data are presente

ISSN:0006-3592    

DOI:10.1002/bit.260290117

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1987

数据来源: WILEY

ISSN:0006-3592    

DOI:10.1002/bit.260290118

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1987

数据来源: WILEY

ISSN:0006-3592    

DOI:10.1002/bit.260290119

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1987

数据来源: WILEY

ISSN:0006-3592    

DOI:10.1002/bit.260290101

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1987

数据来源: WILEY