Abstract

The growing concern of antibiotic resistance has enhanced researchers’ focus on phytotherapeutics. Euphorbia hirta and E. hyssopifolia have had and still have considerable importance in the tradition of medicinal East Africa, and to date, they continue to attract numerous pharmacological claims, particularly for their antioxidative potential. This study is a comparative analysis of the chemical constituents and bioactivities of the methanol extracts of the two species. In particular, we evaluated their antioxidant and antibacterial activities and their potential inhibition of important enzymes. Specimens of E. hirta and E. hyssopifolia were collected from Rabat, Morocco and were later macerated in methanol. We conducted qualitative phytochemical analysis and quantitative spectrophotometry analysis for total polyphenols, flavonoids, and tannins. For more detailed analysis, Gas Chromatography-Mass Spectrometry (GC-MS) was used. The DPPH radical scavenging assay was used to evaluate antioxidant activity, while the antibacterial activity against seven pathogenic bacteria was evaluated using the agar diffusion method. Finally, we performed molecular docking studies to evaluate the binding affinities of key metabolites against DNA gyrase subunit B (GyrB) and human Glutathione S-transferase A1 (hGSTA1). For both E. hirta (3.80%) and E. hyssopifolia (3.20%) the extraction yield was comparable, but E. hirta had a slightly higher yield. We also performed a phytochemical screening, which showed that E. hirta was rich in triterpenes and sterols (~40%) while 9,19-cyclolanost-24-en-3-ol (29.71%) was the most dominant compound. On the other hand, E. hyssopifolia had a substantial amount of unsaturated fatty acids, particularly linoleic acid (8.51%). Additionally, E. hyssopifolia had a noticeably higher total polyphenols and total gallic acid equivalents concentration and a greater antioxidant capacity (IC50 = 0.069 mg/mL) than E. hirta (IC50 = 0.180 mg/mL) and standard ascorbic acid. Both extracts had considerable antibacterial properties, particularly versus Staphylococcus aureus. β-sitosterol and 9,19-cyclolanost-24-en-3-ol were the most potential ligands in the molecular docking analysis, having high binding affinities to the active sites of the target enzymes. This study highlights the clinical potential of E. hirta and E. hyssopifolia including their varying biochemical and biological attributes. As E. hirta outweighs with higher triterpenes and sterols, it constitutes better anti-inflammatory potential. On the other hand, E. hyssopifolia, with strong potential as an antioxidant, is best to work on. This potential supports their traditional ethnobotanical uses and shows its potential as a new natural bioactive compound E. hyssopifolia.