Medicinal plants are an important source of bioactive secondary metabolites that are responsible for the development of new drugs. The main aim of this study was to explore Pistacia integerrima J. L. Stewart ex Brandis phytochemically and biologically explore P. integerrima . The defatted methanolic extract of P. integerrima galls was subjected to column chromatography, which yielded six flavonoids including 3,5,7,4/-tetrahydroxy-flavanone ( 1 ), naringenin ( 2 ), 3,5,4/-trihydroxy,7-methoxy-flavanone ( 3 ), sakuranetin ( 4 ), spinacetin ( 5 ), and patuletin ( 6 ). The defatted extract and the isolated compound ( 1–6 ) were assessed for in- vitro xanthine oxidase (XO). The samples to be tested were applied at a concentration of 0.5 mM and demonstrated a variable degree of XO inhibitory potential. The maximum inhibitory effect was observed for compound 6 (93.09%), followed by compounds 5 (89.02%) and 3 (87.92%). Six flavonoids from P. integerrima galls showed favorable drug-likeness, good gastrointestinal (GI) absorption (except for compound 6 ), and safe oral toxicity profiles. Docking and in vitro assays identified compounds 3 , 5 , and 6 as potent XO inhibitors that outperformed allopurinol. Density functional theory (DFT) analysis revealed that compound 3 was stable but less reactive, whereas compounds 5 and 6 were more reactive, with strong electrophilic properties. Furthermore, MD simulations confirmed the stable binding of these three compounds within the XO active site, with compound 6 demonstrating the highest interactions and structural stability. In conclusion, P. integerrima flavonoids, particularly compound 6 , are significant XO inhibitors that may be used to treat hyperuricemia and hypoxic-ischemic encephalopathy (HIE).
Rauf et al. (Fri,) studied this question.