Comparative study of Bark and Leaves Extract of Prosopis cineraria on Antioxidant and Antimicrobial Activity through Quantitative Evaluation of Phytoconstituents

Abstract

Objective: The current scenario was aimed to evaluate the antioxidant and antimicrobial potential activities of bark and leaves crude extract of Prosopis cineraria.

Methodology: The assay was carried out for phytochemical screening, antibacterial and antioxidant activity. A spectrophotometric analysis was used to assess the total phenolic content (TPC), the total flavonoid content (TFC) and the total tannin content (TTC). The research was performed using various In vitro methods using 1, 1-diphenyl-2-picrylhydrazyl (DPPH), Hydrogen peroxide radical scavenging assays (H₂O₂) and Ferric reduction assay (FRAP) assay. The antimicrobial activity was determined by disc diffusion and minimum inhibitory concentration (MIC) methods against four bacterial and three fungal strains.

Results: The total phenolics and flavonoid content were found to be higher in Hydroalcohol solvent of bark (98.01 ± 1.80 mg GAE/g and 66.95 ± 1.66 mg RE/g respectively) and in methanolic extract of leaves (72.00 ± 1.35 mg GAE/g and 54.46 ± 0.97 mg RE/g respectively).While the tannin content in Hydroalcohol extract of bark (56.30 ± 0.514 mg TAE/g) is more than methanolic extract of leaves (22.65 ± 0.36 mg TAE/g). FRAP value was higher in the hydroalcoholic extract of Bark (537.161±8.31 mg equivalents Ascorbic acid /g of extract) than leaf methanolic extract (315.20±7.40 mg equivalents Ascorbic acid /g of extract) leaf. The hydroalcohol extract of bark [IC₅₀- 391.95 ± 0.008 µg/mL (DPPH), IC₅₀ - 220.44 ± 0.0005 µg/mL (H₂O₂)] and methanol extract of leaves [IC₅₀- 215.64 ± 0.333 µg/ mL (DPPH), IC50- 138.68±1.160 µg/mL (H₂O₂)] showed more antioxidant potential as compared to that of others crude extract and even ascorbic acid. The maximum antimicrobial activity was shown by Hydroalcoholic solvent of bark is high rather than methanol solvent of leaves. The zone of inhibition of Hydroalcohol bark extract is7.66 ±2.08 mm, 8.33±1.52 mm, 10±1 mm and 11.33± 1.52mm was observed against Bacillus subtilis, Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa respectively. In case of methanol extract of leaves , zone of inhibition  4.33 ±1.154 mm, 5.33 ± 2.081 mm, 7.66 ± 1.527 mm and 6.0 ± 3.0 mm was observed against B. subtilis, S. aureus, E. coli, and P. aeruginosa respectively.

Conclusion: The results of this systematic study show that clearly indicated comparative strong possible antioxidant potential and antimicrobial activity in extracts of bark and leaves of P. cineraria.