Application of the wavelet image analysis technique to monitor cell concentration in bioprocesses

Abstract

-The growth of cells of great practical interest, such as, the filamentous cells of bacterium Streptomyces clavuligerus, the yeast Saccharomyces cerevisiae and the insect Spodoptera frugiperda (Sf9) cell, cultivated in shaking flasks with complex media at appropriate temperatures and pHs, was quantified by the new wavelet transform technique. This image analysis tool was implemented using Matlab 5.2 software to process digital images acquired of samples taken of these three types of cells throughoot their cultivation. The values of the average wavelet coefficients (AWCs) of simplified images were compared with experimental measurements of cell concentration and with computer-based densitometric measurements. AWCs were shown to be directly proportional to measurements of cell concentration and to densitometric measurements, making evident the great potential of the wavelet transform technique to quantitatively estimate the growth of several types of cells.

A Comprehensive Survey with Quantitative Comparison of Image Analysis Methods for Microorganism Biovolume Measurements

“…In [ 64 – 66 ], thresholding is applied for bacteria biovolume measurement. First, contour enhancement [ 64 ] is applied for pre-processing.…”

A Comprehensive Survey with Quantitative Comparison of Image Analysis Methods for Microorganism Biovolume Measurements

“…In [16,58,47], thresholding is applied for bacteria biovolume measurement. First, contour enhancement [16] is applied for pre-processing.…”

“…Finally, the quantity of elements can be measured. In [47], the useless particles are removed after thresholding segmentation. Then the wavelet transformation and densitometric techniques are applied to quantitatively estimate the growth of cells.…”

“…At first, thresholding based image segmentation methods are widely used for microorganism biovolume measurement. Global thresholding can easily segment the regions of colony after proper pre-processing, such as the works in [47]. The results of global thresholding on a benchmark dataset are shown in Fig.…”

Ozone Dosage is the Key Factor of Its Effect in Biological Systems

“…Figure 4 represents the specific areas that demonstrate the tumor activity by color variation. The red color corresponds to larger tumor activity, and, contrary to that, the blue areas describe the regions with smaller or even null activities [30][31][32][33]. Figure 4b corresponds to the mice dosed with dissolved oxygen, showing an area in red color that is larger than the one detected for the mice of the control group.…”