Comparative Phytochemical, Antioxidant, and Antibacterial Study of Different Solvent Extracts of Cissus hastata Leaves

Introduction: Plants have long been utilized in traditional medicine for treating a variety of diseases. Plant-derived extracts are a rich source of phytochemicals with documented antibacterial and antioxidant properties. Objective: This study aimed to investigate and compare the phytochemical profiles, antioxidant capacities, and antibacterial activities of various crude extracts from the leaves of Cissus hastata. Methods: Leaf extracts of C. hastata were prepared using hexane (Hex), ethyl acetate (EtOAc), 95% ethanol (EtOH), and 50% ethanol (AqE). These extracts were analyzed for preliminary phytochemical constituents, total phenolic content (TPC), total flavonoid content (TFC), antioxidant activity (DPPH, ABTS, and FRAP assays), and antibacterial activity against five bacterial strains: Staphylococcus aureus (TISTR 517), methicillin-resistant Staphylococcus aureus (MRSA 142), Bacillus cereus (ATCC 11778), Escherichia coli (ESBL 182), and Salmonella typhimurium (TISTR 292). Results: Phytochemical screening of different solvent extracts of C. hastata leaves revealed the presence of diverse bioactive compounds. The EtOAc and AqE extracts exhibited the highest TPC (65.31 ± 1.85 and 61.45 ± 3.34 mg GAE/g extract, respectively) (p < 0.05). In contrast, the EtOH extract showed the highest TFC (29.92 ± 3.42 mg QE/g extract) (p < 0.05). The EtOH and AqE extracts also demonstrated the strongest antioxidant activities in the DPPH (IC50: 307.07 ± 7.18 μg/mL and 316.86 ± 11.78 μg/mL), ABTS (IC50: 160.21 ± 5.43 μg/mL and 208.45 ± 3.84 μg/ mL) (p < 0.05), and FRAP (4.69 ± 0.08 and 4.96 ± 0.07 mM FeSO4/mg extract) assays. The antibacterial activity was observed exclusively against Gram-positive bacteria. Among all the extracts, the AqE extract at a concentration of 100 mg/mL exhibited significant antibacterial effects against Staphylococcus aureus, methicillin-resistant Staphylococcus aureus, and Bacillus cereus, with zones of inhibition measuring 15.43 ± 0.46 mm, 14.76 ± 0.58 mm, and 15.66 ± 1.04 mm, respectively. Conclusion: Ethanol-based extracts of C. hastata leaves demonstrate high antioxidant and antibacterial activities and represent a promising source of bioactive compounds for developing natural therapeutic agents.