Evaluation of Antioxidant Activity, Phytochemicals and ESR Analysis of Lavandula Stoechas

Abstract

The antioxidant activity of phytochemicals and of the methanolic extract of Lavandula stoechas was evaluated by β-carotene-linoleate bleaching, DPPH radical scavenging, ferric reducing/antioxidant power (FRAP). The obtained results were compared with antioxidant activities of synthetic antioxidants, such as BHT and BHA. The highest antioxidant activity of the extract was observed by DPPH radical scavenging assay, which was 84.45 ± 5.1% at 1 mg ml −1 . Rutin, rosmarinic acid, and caffeic acid were main phenolics in the extract. The total phenolic content of the methanolic extract of Lavandula stoechas was found to be 105.5 ± 2.7 mg gallic acid equivalent (GAE). Electron spin resonance (ESR) measurements were also performed on the samples. Free radicals were determined by ESR method. g value was found to be 2.0034 for the Lavandula stoechas; 2.0052 for quercetin.

Identification of radical structures on 1-pentamethylbenzyl-3-ethylimidazoliumsilver(I)bromide and 1,3-bis(pentamethylbenzyl)-4,5-dimethylbenzimidazoliumsilver(I)bromide exposed to gamma rays: an EPR study

“…In recent years, electron paramagnetic resonance (EPR) technique has been widely used for characterization of various materials . Researchers have investigated compounds containing Ag and Br by using EPR method.…”

Antibacterial, antioxidant and anti-proliferative properties and zinc content of five south Portugal herbs

“…These results indicate that phenolics are not responsible for the DPPH scavenging activity and seem to in fact hamper it, since lower phenolic content extracts have a lower DPPH IC 50 . Finally, the L. stoechas studied by Ceylan et al (2015) had a higher caffeic and rosmarinic acids and lower ferulic acid concentrations (87.5 versus 3.94 mg/100 g; 834.7 versus 301.71 mg/100 g and 3.3 versus 17.30 mg/100 g, respectively). In addition they also identified quercetin, rutin and coumaric acid.…”

Phytochemical profiling of anti‐inflammatory Lavandula extracts via RP–HPLC–DAD–QTOF–MS and –MS/MS: Assessment of their qualitative and quantitative differences

“…On the contrary, more polar fractions were mainly prepared by conventional SLE with pure solvents, including ethanol, methanol, aqueous solutions of them, etc. . In these works phenolic compounds were determined by LC‐DAD .…”

“…GC‐MS has been applied to determine Lavandula phenolic compounds, but it required previous extraction and derivation steps . Other studies have also used LC coupled to UV‐Vis and DAD . Only up to 21 phenolic compounds were characterized; a number lower than that of volatile compounds reported in EOs when using GC‐MS.…”