Software for coding, generation and selection of UVCB constituents
UVCB explorer software, developed by LMC, is software for coding, generation and selection of constituents of substances of unknown or variable composition, complex reaction products, or biological materials (UVCBs). It includes two computer-interpretable formats: Generic Simplified Molecular-Input Line-Entry System (GSMILES) and Generic Graph (GGRAPH). GSMILES is a SMILES-based single line notation coding fixed and variable structural features of UVCBs, whereas GGraph represents the entire workflow. The GGraph allows coding of the generic description of UVCB in G SMILES followed by generation of constituents, selection of representative structures and storage of the generated/selected representatives.
There are two main types of selection of constituents. The first one is an endpoint driven selection based on ranges of a characteristic physicochemical property, e.g. logKow values are critical when assessing bioaccumulation potential. The second approach is a statistical selection of the minimum number of generated constituents representing a UVCB. This representative sample is selected in such a way that the structural variability and the properties of concern of the UVCB are approximated within a predefined tolerable error. The aim of the statistical selection is to enable the assessment of UVCB substances by decreasing the number of constituents that need to be evaluated. The procedure, which is shown to be endpoint independent, was validated theoretically and on real case studies.