Oral Bioavailability Screening and Drug-Likeness Prediction

Oral bioavailability (OB) prescreening, which indicates the fraction of the oral dose of drug that reaches the bloodstream, is one of the important stages of drug discovery and development. In this work, the OB values were calculated by a robust in silico model OBioavail 1.131 (link)32 (link). In addition, drug-likeness is a qualitative concept used in drug screening for evaluating the structural similarity between the compounds and the drugs in the DrugBank database, which is estimated at the early stage of drug discovery11 (link). The drug-likeness prediction method was shown as follows:

where a represents the herbal ingredients, and b represents the average molecular drug-likeness index of all drugs in the DrugBank database. Finally, OB ≥ 30% and drug-likeness index ≥0.18 were set as the threshold to select candidate compounds. Additionally, several compounds, such as icariside I, bergenin, tangeretin, naringin, hesperidin, paeonioflorin, and paeonolide initially were omitted according to these screening rules; however, these compounds were supported by experimental evidence and, therefore, also were obtained as candidate compounds for further analysis13 (link)33 (link)34 35 (link)36 (link)37 (link)38 (link).