COMT and Parkinson disease: The overall analysis hypothesized, all of these nine phyochemicals (withaphysalin N, withaphysalin F, withaphysalin O, withaphysalin C, withaphysalin D, withanolideB, withaferinA, withacnistin, and withasomnine) of plant W. somnifera have potential binding efficiency and may be used as putative inhibitors against PD drug target COMT.