ISSN:
0006-3592
Keywords:
Chemistry
;
Biochemistry and Biotechnology
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Biology
,
Process Engineering, Biotechnology, Nutrition Technology
Notes:
A microcoaxial needle sensor with a tip diameter of ca. 0.7 μm was used as a microprobe to measure profiles of dissolved oxygen tension (DOT) within fixed pellets of Penicillium chrysogenum as a function of the DOT level around the pellet, in the presence and absence of bulk convective flow and turbulence. The investigations indicate that the oxygen transfer mechanism is complex. The results were interpreted by assuming the penetration convective flow into the entire pellet and penetration of turbulence into the outer range. A model was developed which was able to describe the measured DOT profiles very well. The model takes into account molecular and turbulent diffusion as well as convective flow as transfer mechanisms inside of the pellet. Structures of pellets used for microprobe measurements were evaluated by histological investigations. Considerable variations of mycelial density with radius within the pellets were found.
Additional Material:
20 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/bit.260280713
