Phytochemical screening and in vitro antioxidant activity of extracts of Cordia macleodii Hook. F. & Thomson bark

Indian subcontinent is the native home of the small deciduous Cordia macleodii Hook. f. & Thoms (Boraginaceae) tree. The bark of C. macleodii is traditionally used in ethnomedicine to treat jaundice and wound. Previous studies have also documented its antioxidant, anti-bacterial, anti-fungal and anti-inflammatory properties. Sequential extraction with 70% ethanol (CMEE) and deionized water (CMAE) yielded 3.84% and 7.89% extract, respectively. Quantitative analysis showed that the ethanolic extract (CMEE) had higher total phenolic content (TPC: 15.43 ± 0.31 mg GAE/g) and total flavonoid content (TFC: 159.46 ± 0.002 mg QE/g) than the aqueous extract (CMAE; TPC: 14.30 ± 0.47 mg GAE/g, TFC: 101.20 ± 0.003 mg QE/g). The preliminary phytochemical screening revealed the presence of cardiac glycoside, alkaloid, saponin, phalbotanin, terpenoid, triterpenoid, phenol, carbohydrate, and coumarin. Quantitative analysis showed that the ethanolic extract (CMEE) had higher total phenol content (TPC: 15.43 ± 0.31 mg GAE/g) and total flavonoid content (TFC: 159.46 ± 0.002 mg QE/g) than the aqueous extract (CMAE; TPC: 14.30 ± 0.47 mg GAE/g, TFC: 101.20 ± 0.003 mg QE/g). Consistent with this, CMEE demonstrated superior antioxidant activity in DPPH (IC50 CMEE: 6.46 ± 0.73 µg/ml) and ABTS (IC50 CMEE: 2.75 ± 0.33 µg/ml) assay compared to CMAE (DPPH IC50: 7.18 ± 0.84 µg/mL; ABTS IC50: 5.73 ± 0.14 µg/mL). The FTIR analysis revealed that the presence of several functional groups like phenol, flavonoid, carboxylic acid, alkane, ketone, ester, ether, aromatic ring, sulphate ester, alkene and halogen group. The GC–MS analysis C. macleodii bark extacts showed presence of several bioactive compounds, including terpenoids, naphthalene derivatives, azulenemethanol, dioxopyridazines, and steroidal pregnane compounds. The drug-likeness evaluation conducted using ADME demonstrated that the compounds of C. macleodii bark have good water solubility, physicochemical properties and pharmacokinetic profile which make these compounds ideal for drug development.