Industrial Biotransformations

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7 Quantitative Analysis of Industrial Biotransformations
When the substrate or product is not a liquid but a solid with a low solubility, the high
product titers required for industrial processes may also lead to suspension reactions.
Product precipitation occurs in at least 15 industrial processes, usually in aqueous solvents.
In about half of these cases, a suspension of a substrate is converted into a suspension
of a product.
The product titer has been found for a minority of the processes (see Figure 7.8), but
this may be sufficient to draw some interesting conclusions. Only in rare cases is the
product titer below 10 g L –1 . In most cases it is well above 100 g L –1 , with occasional values
of about 500 g L –1 , irrespective of the product type. Thus, achievement of high product
titers could be one of the strong points of biotransformation processes.
product titer in
g/L
> 300
100 to 300
30 to 100
10 to 30
3to10
1to3