Details
| Original language | English |
|---|---|
| Pages (from-to) | 24-35 |
| Number of pages | 12 |
| Journal | Biotechnology and Bioengineering |
| Volume | 60 |
| Issue number | 1 |
| Publication status | Published - 5 Dec 1998 |
Abstract
A sensor is presented, which allows on-line microscopic observation of microorganisms during fermentations in bioreactors. This sensor, an In Situ Microscope (ISM) consists of a direct-light microscope with a measuring chamber, integrated in a 25 mm stainless steel tube, two CCD-cameras, and two frame-grabbers. The data obtained are processed by an automatic image analysis system. The ISM is connected with the bioreactor via a standard port, and it is immersed directly in the culture liquid - in our case Saccharomyces cerevisiae in a synthetic medium. The microscopic examination of the liquid is performed in the measuring chamber, which is situated near the front end of the sensor head. The measuring chamber is opened and closed periodically. In the open state, the liquid in the bioreactor flows unrestricted through the chamber. In closing, a defined volume of 2,2 · 10- 8 mL of the liquid becomes enclosed. After a few seconds, when the movement of the cells in the enclosed culture has stopped, they are examined with the microscope. The microscopic images of the cells are registered with the CCD- cameras and are visualized on a monitor, allowing a direct view of the cell population. After detection, the measuring chamber reopens, and the enclosed liquid is released. The images obtained are evaluated as to cell concentration, cell size, cell volume, biomass, and other relevant parameters simultaneously by automatic image analysis. With a PC (486/33 MHz), image processing takes about 15 s per image. The detection range tested when measuring cells of S. cerevisiae is about 106 to 109 cells/mL (equivalent to a biomass of 0.01 g/L to 12 g/L). The calculated biomass values correlate very well with those obtained using dry weight analysis. Furthermore, histograms can be calculated, which are comparable to those obtained by flow cytometry.
Keywords
- Biomass, Cell concentration, Cell morphology, Histogram, Image analysis, In situ microscopy
ASJC Scopus subject areas
- Biochemistry, Genetics and Molecular Biology(all)
- Biotechnology
- Chemical Engineering(all)
- Bioengineering
- Immunology and Microbiology(all)
- Applied Microbiology and Biotechnology
Cite this
- Standard
- Harvard
- Apa
- Vancouver
- BibTeX
- RIS
In: Biotechnology and Bioengineering, Vol. 60, No. 1, 05.12.1998, p. 24-35.
Research output: Contribution to journal › Article › Research › peer review
}
TY - JOUR
T1 - In situ microscopy for on-line determination of biomass
AU - Bittner, C.
AU - Wehnert, G.
AU - Scheper, T.
PY - 1998/12/5
Y1 - 1998/12/5
N2 - A sensor is presented, which allows on-line microscopic observation of microorganisms during fermentations in bioreactors. This sensor, an In Situ Microscope (ISM) consists of a direct-light microscope with a measuring chamber, integrated in a 25 mm stainless steel tube, two CCD-cameras, and two frame-grabbers. The data obtained are processed by an automatic image analysis system. The ISM is connected with the bioreactor via a standard port, and it is immersed directly in the culture liquid - in our case Saccharomyces cerevisiae in a synthetic medium. The microscopic examination of the liquid is performed in the measuring chamber, which is situated near the front end of the sensor head. The measuring chamber is opened and closed periodically. In the open state, the liquid in the bioreactor flows unrestricted through the chamber. In closing, a defined volume of 2,2 · 10- 8 mL of the liquid becomes enclosed. After a few seconds, when the movement of the cells in the enclosed culture has stopped, they are examined with the microscope. The microscopic images of the cells are registered with the CCD- cameras and are visualized on a monitor, allowing a direct view of the cell population. After detection, the measuring chamber reopens, and the enclosed liquid is released. The images obtained are evaluated as to cell concentration, cell size, cell volume, biomass, and other relevant parameters simultaneously by automatic image analysis. With a PC (486/33 MHz), image processing takes about 15 s per image. The detection range tested when measuring cells of S. cerevisiae is about 106 to 109 cells/mL (equivalent to a biomass of 0.01 g/L to 12 g/L). The calculated biomass values correlate very well with those obtained using dry weight analysis. Furthermore, histograms can be calculated, which are comparable to those obtained by flow cytometry.
AB - A sensor is presented, which allows on-line microscopic observation of microorganisms during fermentations in bioreactors. This sensor, an In Situ Microscope (ISM) consists of a direct-light microscope with a measuring chamber, integrated in a 25 mm stainless steel tube, two CCD-cameras, and two frame-grabbers. The data obtained are processed by an automatic image analysis system. The ISM is connected with the bioreactor via a standard port, and it is immersed directly in the culture liquid - in our case Saccharomyces cerevisiae in a synthetic medium. The microscopic examination of the liquid is performed in the measuring chamber, which is situated near the front end of the sensor head. The measuring chamber is opened and closed periodically. In the open state, the liquid in the bioreactor flows unrestricted through the chamber. In closing, a defined volume of 2,2 · 10- 8 mL of the liquid becomes enclosed. After a few seconds, when the movement of the cells in the enclosed culture has stopped, they are examined with the microscope. The microscopic images of the cells are registered with the CCD- cameras and are visualized on a monitor, allowing a direct view of the cell population. After detection, the measuring chamber reopens, and the enclosed liquid is released. The images obtained are evaluated as to cell concentration, cell size, cell volume, biomass, and other relevant parameters simultaneously by automatic image analysis. With a PC (486/33 MHz), image processing takes about 15 s per image. The detection range tested when measuring cells of S. cerevisiae is about 106 to 109 cells/mL (equivalent to a biomass of 0.01 g/L to 12 g/L). The calculated biomass values correlate very well with those obtained using dry weight analysis. Furthermore, histograms can be calculated, which are comparable to those obtained by flow cytometry.
KW - Biomass
KW - Cell concentration
KW - Cell morphology
KW - Histogram
KW - Image analysis
KW - In situ microscopy
UR - http://www.scopus.com/inward/record.url?scp=0032487328&partnerID=8YFLogxK
U2 - 10.1002/(SICI)1097-0290(19981005)60:1<24::AID-BIT3>3.0.CO;2-2
DO - 10.1002/(SICI)1097-0290(19981005)60:1<24::AID-BIT3>3.0.CO;2-2
M3 - Article
C2 - 10099402
AN - SCOPUS:0032487328
VL - 60
SP - 24
EP - 35
JO - Biotechnology and Bioengineering
JF - Biotechnology and Bioengineering
SN - 0006-3592
IS - 1
ER -