In Vitro antioxidant and antibacterial activity of leaf extracts of Measa lanceolata

Abstract

This study investigated total phenolic contents (TPC), total flavonoid contents (TFC), antioxidant activity, and antibacterial activities of different leaf extracts of Measa lanceolata. The TPC and TFC of the extracts were determined by Folin-Ciocalteu and aluminum chloride methods, respectively. The 2, 2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging, reducing power, and phosphomolybedinium assays were used to evaluate antioxidant activity. Antibacterial properties were assessed using the disc-diffusion assay based on minimum inhibitory concentration (MIC). Bacteria tested were three strains of gram-negative (Escherichia coli (ATCC-25922), Proteus vulgaris (ATCC-13315), and Pseudomonas aeruginosa (ATCC-43495)), and two strains of gram-positive (Staphylococcus aureus(ATCC-25923), and Enterococcus faecalis(ATCC-29212)). It was found that methanol extract contained the highest TPC (60.6 ± 4.4 mg of gallic acid equivalent/g of dried extract) and TFC (6.4 ± 6.0 mg of catechin equivalent/g of dried extract). Extract showed the strongest DPPH radical scavenging activity (EC 50 = 76.7 ± 7.3 µg/mL), iron reducing power (EC 50 = 74.0 ± 1.6 µg/mL), and total antioxidant activity (128 ± 4 mg of ascorbic acid equivalent per dried extract). Inhibition zones were observed in water and methanol extracts against bacterial strains, whereas Staphylococcus aureus (ATCC-25923), Escherichia coli(ATCC-25922), Pseudomonas aeruginosa (ATCC-43495), and Proteus vulgaris(ATCC-13315) were resistant against chloroform and ethyl-acetate extracts.

Comparative analysis of phenolic, flavonoid and antioxidant content in root vegetables from organic and conventional production

“…Determination of total phenolic contents (TPC). Total phenolic content was estimated by Folin-Ciocalteu method as described in Jundi et al (2021). To 0.1 mL of the extract, 1 mL Folin-Ciocalteu reagent (diluted ten times) was added and the mixture was left for 5 minutes and then 1 mL of sodium carbonate was added.…”

A comparative study on the antioxidant activity of <i>Gladiolus dalenii</i> Van Geel and nine commonly used substances to compare the antioxidant activity of foods and medicinal plants

“…The TPC was measured spectrophotometrically using the Folin-Ciocalteu (FC) method described by Ismael et al (2021), with some modifications, In brief, 500 µL of extract (1 mg/mL) (dissolved in methanol) was mixed with 500 µL of FC reagent (diluted 10 times). After 5 minutes, 1 mL of a 7.5% sodium carbonate and 3 mL of distilled water were added and mixed thoroughly.…”

“…TFC was measured following a method described by Ismael et al (2021), with some modifications, briefly, 500 µL of extract (1mg/mL), 2.5 mL of distilled water, 250 µL (5%) of NaNO 2 were mixed. After 6 min, 250 µL of 2% AlCl 3 reagent (methanol solution) was added.…”

In vitro antibacterial activity of fruit pulp extracts of Tamarindus indica against Staphylococcus aureus and Klebsiella pneumoniae

“…Although antibacterial activity of ethanol and aqueous extract of T. indica fruit pulp against some bacterial strains using agar well diffusion and macro broth dilution techniques have been reported in Nigeria [ 26 ]. However, the antibacterial activity of medicinal plant extracts dependent on various factors; namely the solvent that used for the extraction [ 27 ], the environmental and climate conditions under which the plant grew could affect the accumulation of bioactive pharmaceutical ingredients that are found in the plants [ 28 ], test concentration of the extract, the choice of the extraction method, the method of antibacterial activity test and the test microorganisms [ 29 ]. Disc diffusion assay offers many advantages over other methods: simplicity, low cost, the ability to test enormous numbers of microorganisms and antimicrobial agents, and the ease to interpret results [ 30 ].…”