Comparative evaluation of antimicrobial and antioxidant potential of ethanolic extract and its fractions of bark and leaves of Terminalia arjuna from north-western Himalayas, India

Abstract

The present study was aimed to evaluate the antimicrobial and antioxidant potential of ethanolic extract and its different solvent fractions (chloroform, ethyl acetate, n-butanol and aqueous fraction) of bark and leaves of Terminalia arjuna. The antimicrobial activity was determined by disc diffusion and minimum inhibitory concentration (MIC) methods against six bacterial stains. The antioxidant activity was evaluated by using DPPH, FRAP and Nitric oxide (NO) scavenging assay. The total phenolics and flavonoid content were found to be higher in n-butanolic fraction of bark (294.6 ± 8.1 mg/g GAE and 168.6 ± 12.3 mg/g RE, respectively) and leaves (203.7 ± 7.0 mg/g GAE and 144.8 ± 11.1 mg/g RE, respectively). The maximum antimicrobial activity was shown by n-butanolic fraction of bark and leaves. The zone of inhibition of 15.0 ± 0.7 mm, 15.5 ± 0.7 mm, 15.0 ± 1.5 mm, 15.5 ± 0.7 mm, 15.0 ± 0.7 mm, 15.0 ± 0.7 mm was observed against Bacillus subtilis, Staphylococcus aureus, Eschericia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa and Salmonella typhi respectively. In case of leaves extract, zone of inhibition of 13.5 ± 0.7 mm, 16.5 ± 0.7 mm, 14.0 ± 0.5 mm, 15.0 ± 0.5 mm, 13.5 ± 0.7 mm, 14.0 ± 0.7 mm was observed against B. subtilis, S. aureus, E. coli, K. pneumoniae, P. aeruginosa, S. typhi, respectively. The n-butanol fraction of bark [IC50-4.1 μg/ml (DPPH), 21.0 μM (FRAP), 3.3 μg/ml (NO)] and leaves [IC50-4.8 μg/ml (DPPH), 28.9 μM (FRAP), 3.2 μg/ml (NO)] showed more antioxidant potential as compared to that of crude ethanolic extract, ethyl acetate fraction, chloroform fraction, aqueous fraction and even ascorbic acid. These results clearly indicated comparative antioxidant potential and antimicrobial activity in extracts of bark and leaves of T. arjuna.

Variability of phenolic and alkaloid content in different plant parts of Carissa edulis Vahl and Zanthoxylum chalybeum Engl.

“…Through indigenous knowledge [ 4 , 6 – 8 ], plants and plant parts that confer more efficacy have been identified. However, studies indicate that the nature and quantity of phyto-compounds differs among and within plant species and can be organ dependent within an individual [ 2 , 9 ]. Quantitative or qualitative medicinal properties are also affected by post-harvesting processes [ 10 ].…”

Sequential Fractionation by Organic Solvents Enhances the Antioxidant and Antibacterial Activity of Ethanolic Extracts of Fruits and Leaves of Terminalia bellerica from North Western Himalayas, India

“…similar to present study, study on ethanolic extract and its fraction of T. arjuna showed that the fraction enriched with phenolic and flavonoid content showed more antimicrobial and antioxidant activity as compared to crude ethanolic extract. 51 The results suggested that antibacterial and antioxidant activity of plant extracts also depend on the type of solvent also.…”

Taraxacum Genus: Potential Antibacterial and Antifungal Activity

“…Similar extracts had antimicrobial effects on four species that induce acne (P. ovale, P. acnes, P. aeruginosa, and S. aureus)i n broth dilution tests with effects depending on the extract concentration, but no further information was available [49]. Moreover, a leaf extract (0.04 mg/well) was reported as a bactericidal agent against S. aureus and fungistatic against C. albicans [52]. Contrarily, extracts of 130 and 200 mg/mL from aerial parts were unable to prevent the growth of 34 microorganisms from genera Bacillus, Enterobacter, Klebsiella, Listeria, Pseudomonas, Salmonella, Staphylococcus, Aspergillus, and Candida, among others; therefore, it was considered inactive at these concentrations in a disc diffusion assay [66].…”