Abstract
The present study investigated the phytochemical composition, antioxidant activity, and antimicrobial activity of successive bark extracts of Tamarix brachystachys. Dried bark was sequentially extracted with hexane, chloroform, and methanol using a Soxhlet apparatus. Total phenolic and flavonoid content were determined by microplate-based colorimetric assays, and antioxidant activity was evaluated using the DPPH radical-scavenging assay with ascorbic acid as the reference. The methanol extract contained the highest total phenolic (19.216 ± 1.1 mg GAE/g) and flavonoid contents (7.901 ± 0.6 mg CE/g). The methanol extract showed the strongest DPPH scavenging activity among the extracts (IC50 = 17.32 µg/mL), followed by chloroform (22.67 µg/mL), while the hexane extract was weaker (estimated IC50 ≈ 68.26 µg/mL); ascorbic acid showed an IC50 of 7.68 µg/mL. Antimicrobial activity was evaluated against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Streptococcus pneumoniae, and Candida albicans using a 96-well microplate assay. The methanol extract showed the strongest overall activity, with a minimum inhibitory concentration (MIC) of 500 µg/mL against all tested microorganisms. Concentration–response analysis also showed lower IC50 values for the methanol extract, particularly against S. aureus (47.7 µg/mL), C. albicans (62.6 µg/mL), and S. pneumoniae (85.5 µg/mL). GC–MS profiling of the hexane extract showed p-camphorene as the dominant detected constituent (57.563% area), while the chloroform extract was characterized by several lipophilic constituents, with 1,3-benzenedicarboxylic acid, bis(2-ethylhexyl) ester giving the largest chromatographic area (23.59%). HPLC analysis of the methanol extract was used for qualitative identification of selected phenolic and flavonoid constituents by comparison with authentic standards. These findings indicate that solvent polarity markedly influenced both the chemical profile and antimicrobial response of the bark extracts.
| Has the manuscript been published | not published |
|---|---|
| Intend to be published in the IJPS ? | Yes |
