Antioxidant and antibacterial activities of leaves and branches extracts of Tecoma stans (L.) Juss. ex Kunth against nine species of pathogenic bacteria

Abstract

Tecoma stans of the Bignoniaceae family, is an important medicinal plant. Different extracts of the leaves and branches of T. stans were evaluated as antibacterial potential against the growth of some human bacterial strains using the disc diffusion and minimum inhibitory concentration (MIC) methods as well as the antioxidant activity by 2,2-diphenyl-1-picrylhydrazyl (DPPH) method. Total phenolic and total flavonoid contents were determined. The different extracts of T. stans were obtained by successive solvent extraction with methanol and its fractions; ethyl acetate (EtOAc), chloroform (CHCl 3 ), n-butanol and aqueous. The methanol, EtOAc and CHCl 3 extracts of T. stans showed significant effect against the tested bacteria (Bacillus subtilis, Micrococcus luteus, Sarcina lutea, Staphylococcus aureus, Escherichia coli, Serratia marcescens, Salmonella typhi, Proteus vulgaris and Pseudomonas aeruginosa). The methanol extract of the leaves exhibited the highest amount of total phenolics (50.3±3 mg gallic acid equivalents/g extract) and flavonoids (40.66±5.03 mg catechin equivalents/g extract). The EtOAc fraction of leaves and branches extracts showed the highest total antioxidant activity (%) with 83.4±0.31 and 82.06±0.54%, respectively followed by CHCl 3 fraction of leaves extracts (79.17±0.20%). These findings provide scientific evidence to support traditional medicinal uses of T. stans and indicate a promising potential for the development of an antibacterial and antioxidant agent from T. stans trees.

Phytochemistry Profile, Antimicrobial and Antitumor Potential of the Methanolic Extract of Tabernaemontana catharinensis A DC and Eragrostis plana NEES

“…Our results, using crude extract, present antimicrobial activity at lower concentrations than that indicated in the cited study, being less than 500 µ g/mL for both extracts, emphasizing the potential use of plants as an antimicrobial agent. The solvent chosen for preparing and obtaining the crude extract seems to be closely related to the increase or decrease in antimicrobial activity [ 52 , 53 ].…”

Evaluation of antioxidant activity and toxicity in Artemia salina of the ether extract and fractions from Tecoma stans seeds

“…Dry leaves extract, obtained by percolation with water/ethanol (1:1), and the fractions of petroleum ether, ethyl acetate and methanol showed antioxidant activity, being hydroethanolic extract the most active, with 64.32% of DPPH inhibition (Larbie, Nyarkoh & Adjei, 2019). Leaves and branches extracts obtained by maceration exhibited IC50 values between 10 and 100 µg/mL (Larbie, Nyarkoh & Adjei, 2019;Salem et al, 2013). The results obtained for the seeds were more promising than for the other plant parts.…”

“…Ex Kunth is a species belonging to the Bignoniaceae family, popularly known as yellowing, yellow bell and garden little ipe (Kranz & Passini, 1997). This species exhibits antibacterial, antioxidant, antinociceptive, antiinflammatory, antidiabetic and larvicidal activities; and these effects are correlated to presence of alkaloids, anthraquinones, phenolic compounds, steroids, glycosides, hydrocarbons, essential oils, tannins, terpenes and saponins (Alonso-Castro et al, 2010;Prasanna et al, 2013;Salem et al, 2013). Studies with T. stans seeds are scarce and it have potential in the search for natural compounds with biological activities.…”

Microencapsulation of Tecoma stans Extracts: Bioactive Properties Preservation and Physical Characterization Analysis

“…In México, it is mainly used to treat diabetes through leaf infusion intake [1,2]. As a result of its broad usage in traditional medicine, the bark, flower, and leaves of the plant have been subject to in vivo and in vitro analysis, showing pharmacological properties that include antidiabetic and hypoglycemic [3][4][5], antioxidant [6][7][8], antimicrobial and antifungal [9][10][11][12], anti-inflammatory [13,14], cardioprotective [15], hepatoprotective [16], antiulcer [17], and anticancer [18].…”