Phytochemical Characterization, Antioxidant and Antimicrobial Evaluation of Medicinal Plants for Polyherbal Gel Development

Four authenticated medicinal plant materials—stems of Tridax procumbens, Andrographis paniculata and Tinospora cordifolia, and bark of Aegle marmelos—were compared using hydroalcoholic extraction (ethanol–water, 70:30, v/v). Extraction yield, qualitative phytochemical reactions, thin-layer chromatography (TLC), total phenolic content (TPC), total flavonoid content (TFC) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging activity were evaluated. Two extracts were subsequently examined by high-performance TLC (HPTLC) and agar-well diffusion against four bacterial species. Extraction yields ranged from 14.91% to 20.13%. Tinospora cordifolia gave the highest TPC (89.77 ± 1.72 mg gallic acid equivalents/g), TFC (89.43 ± 1.59 mg quercetin equivalents/g) and DPPH inhibition at 100 µg/mL (90.35 ± 1.75%); its reported DPPH IC50 was 46.18 ± 1.04 µg/mL. Tridax procumbens ranked second for these measurements. HPTLC analysis at 254 nm identified three recorded peaks for T. procumbens and six for T. cordifolia, whereas ten were recorded for each extract at 366 nm. In agar-well diffusion testing, T. cordifolia produced larger recorded inhibition zones than T. procumbens for Staphylococcus aureus, Bacillus subtilis, Escherichia coli and Pseudomonas aeruginosa. A separate F3 gel dataset showed recorded zone diameters of 14.20–17.40 mm. The findings offer a strong basis for selecting formulations for further development, optimisation, and validation in future studies.