摘要:

AbstractThe kinetics of growth of aTorulopsissp. was investigated in a continuous culture with glucose or hexadecane as the carbon source; growth was limited by either carbon or nitrogen. The relationship between the concentration of the limited substrate and the steady‐state growth rate of the organism was examined and tested against various models of growth. No existing model was found to describe the growth accurately and a new model has been proposed:\documentclass{article}\pagestyle{empty}\begin{document}$$ \mu = D_T \cdot \frac{s}{{K_s + s}} + as $$\end{document}It is postulated that this behavior would result from a simple first order reaction between the reactants of the rate‐limiting enzymic reaction of the organism's metabol

ISSN:0006-3592    

DOI:10.1002/bit.260181002

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

年代:1976

数据来源: WILEY

摘要:

AbstractFeather meal protein was prepared in granular form and used as a support for lactase using glutaraldehyde as the crosslinking agent. The support gave a high retention of activity and in column operation it yielded apparent half‐lives from 50 to 100 days. Because of its gel‐like consistency (water content of about 90%), there is some diffusional restricting of activity as indicated by the kinetic data of soluble and immobilized enzy

ISSN:0006-3592    

DOI:10.1002/bit.260181003

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

年代:1976

数据来源: WILEY

摘要:

AbstractA method for calculating the mass transfer coefficient in a biological film system, under turbulent flow conditions, is presented. It is experimentally found that fluid velocity has a positive effect on the rate of substrate utilization when the system is operated in other than the kinetic regime. A correlation is developed which indicates a dependence of the mass transfer coefficient on the fluid velocity raised to the 0.7 power.

ISSN:0006-3592    

DOI:10.1002/bit.260181004

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

年代:1976

数据来源: WILEY

摘要:

AbstractThe rate of heat evolution (kcal/liter‐hr) in mycelial fermentations for novobiocin and cellulase production with media containing noncellular solids was measured by anin situdynamic calorimetric procedure. Thermal data so obtained have proved significant both in monitoring cell concentration during the trophophase (growth phase) and in serving as a physiological variable in the fermentation process. The validity of this technique has been demonstrated by closing the overall material and energy balances.The maintenance energy in a batch fermentation can also be calculated by integrating heat evolution data. This integration method is applicable to a fermentation lacking a precise cell growth curve. The maintenance coefficient, obtained for the novobiocin fermentation byStreptomyces niveus, is equal to 0.028 g glucose equivalent/g cell‐hr. The production of novobiocin in the idio‐phase (production phase) also correlates well with the amount of energy catabolixed for maintenance and this results in an observed conversion yield of glucose to novobiocin of 11.8 mg of novobiocin produced per gram of glucose catabolized.A new physiological variable, kilocalories of heat evolved per millimole of oxygen consumed, has been proposed to monitor the state of cells during the fermentation. This method may provide a simple way to monitor on‐line shifts in the efficiency of cell respiration and changes in growth yields during a microbial

ISSN:0006-3592    

DOI:10.1002/bit.260181005

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

年代:1976

数据来源: WILEY

摘要:

AbstractReactor systems based on tapered fluidized beds are being developed for aqueous bioprocesses in which adhering microorganisms or immobilized active biological fractions are used. The use of a fluidized bed prevents biomass buildup, accommodates particulates in the feed stream, is compatible with gas sparging, and allows easy removal or addition of the active materials. The tapered reactor tends to stabilize the fluidized bed, thus allowing a much wider range of operating conditions. Preliminary experimental results and an empirical mathematical model of the tapered bed indicate that bed stability is associated with a decreasing velocity and void‐fraction profile up the bed and the pressure drop across the bed decreases with increasing flow rates.The tapered fluidized bed bioreactor is being evaluated for use in the enzymatic production of hydrogen, microbiological denitrification, and microbiological degradation of coal conversion aqueous waste streams. The enzyme catalyzed conversion of lactose to glucose and galactose was used in the evaluation of the reactor concep

ISSN:0006-3592    

DOI:10.1002/bit.260181006

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

年代:1976

数据来源: WILEY

摘要:

AbstractThe enzyme tyrosinase (E.G. 1.14.18.1) has been immobilized in a polyacrylamide gel and intermittently assayed for enzyme activity over a period of 19 days using phenol as the substrate. The results of these studies indicate that the immobilized enzyme could be incorporated into a system to detect phenol and related compounds that are found in industrial effluents and as surface water contaminants.

ISSN:0006-3592    

DOI:10.1002/bit.260181007

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

年代:1976

数据来源: WILEY

摘要:

AbstractWe have demonstrated the use of bacterial chromatophores for the continuous photosynthetic regeneration of ATP from ADP in an ultrafiltration reactor. Biphasic kinetics of the degradation of chromatophore activity are described. Using chromatophores in combination with the enzyme adenylate kinase, we have also demonstrated continuous regeneration of ATP from AMP.

ISSN:0006-3592    

DOI:10.1002/bit.260181008

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

年代:1976

数据来源: WILEY

摘要:

AbstractThe immobilization ofRhodospirillum rubrumchromatophores was successfully performed by entrapping them in polyacrylamide. Their photophosphorylating activity was about 40% of native chromatophores. The temperature and pH optima for immobilized chromatophores were similar to the native photosynthetic apparatus and kinetic parameters showed that the rate of photophosphorylation in polyacrylamide particles was diffusion controlled. Light penetration of the gel particles was not a limiting parameter. Immobilization considerably increased the stability of the chromatophores towards denaturation.

ISSN:0006-3592    

DOI:10.1002/bit.260181009

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

年代:1976

数据来源: WILEY

摘要:

AbstractThe construction and use of an automated membrane filtration system is described which produces 300 liters per day of sterile medium over at least four months of continuous fermentation. The capacity of the system is limited only by choice of filter type and has applications in continuous pilot plant work or medium‐scale batch fermentation, in the bulk supply of communally used laboratory medium, in supplying banks of small‐scale continuous fermentors, and for remote control of medium supply in hazardous fermentations (e.g., methane) with great savings in time and materials. Only two sterile storage jars are needed, irrespective of the total demand for the med

ISSN:0006-3592    

DOI:10.1002/bit.260181010

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

年代:1976

数据来源: WILEY

摘要:

Abstractα‐Chymotrypsin and acid phosphatase have been immobilized on chitosan, a polyaminosaccharide, without using any intermediate reagent; the immobilized enzymes are active and their activity is much higher than for chitin‐immobilized enzymes. The best pH conditions for operating chitosan columns have been determined and columns have been used to transform substrates in large amounts, with no decrease of activity or enzyme losses. Due to the nonconvalent interaction between chitosan and enzymes, the pure and active enzymes can be eventually recovered from the columns. The effects of metal ions, aldehydes, and salts are reported and discussed. Applications are foreseen in the food and biomedical sciences and indust

ISSN:0006-3592    

DOI:10.1002/bit.260181011

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

年代:1976

数据来源: WILEY