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Physical & Chemical properties

Partition coefficient

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Administrative data

partition coefficient
Type of information:
calculation (if not (Q)SAR)
Adequacy of study:
key study
Study period:
December 2020
1 (reliable without restriction)

Data source

Reference Type:
other: Expert statement
Report date:

Materials and methods

Test guideline
no guideline available
other: Expert statement
Principles of method if other than guideline:
The expert statement is based on the composition of this UVCB subtance which does not allow to perform any test or calculation to estimate the log Kow
GLP compliance:
Type of method:
other: It is demonstrated that the methods available are not applicable to this complex UVCB substance.
Partition coefficient type:

Test material

Constituent 1
Reference substance name:
Saccharomyces cerevisiae cell wall, extracted
EC Number:
Molecular formula:
Not applicable (UVCB substance)
Saccharomyces cerevisiae cell wall, extracted
Test material form:
solid: particulate/powder

Study design

Analytical method:
other: Substance specific analytical methods cannot be developed due to the complex nature of this UVCB substance. And non-specific analytical methods, like TOC, provide sum parameters that are not relevant for log Kow determination.

Results and discussion

Partition coefficient
Key result
log Pow
20 °C
Remarks on result:
not measured/tested
Based on the composition of the substance "Saccharomyces cerevisiae cell wall, extracted" it is technically not feasible to perform an experimental test because the cell wall fraction does not dissolve in water and in octanol. So according to REACH, the study does not need to be conducted. The non-testing approach for the log Kow determination are not applicable to the constituents of this UVCB substance, since the exact structure of the biological macromolecules (e.g. proteins) are not known. Moreover, the main constituents do not fit in the applicability domain of the QSARs due to their high molecular weight (e.g.polysaccharides)

Applicant's summary and conclusion

The log Kow of the substance SACCHAROMYCES CEREVISIAE CELL WALL, EXTRACTED cannot be estimated based on all available experimental and calculation methods.
Executive summary:

Due to the complex composition of the substance constituted by the insoluble cell wall of yeast extract, it is not feasible to determine its partition coefficient experimentally. Indeed, the shake flask method, the HPLC method and the slow-stirring method are not applicable to this substance. QSARs calculations are not possible due to the complex composition and the unknown precise structure of the constituents. Even the estimation of log Kow based on the solubility in water and in n-octanol is technically not feasible because the cell walls extracted during the process, are naturally neither soluble in water, nor soluble in octanol.