Phenolic production and antioxidant properties of some Macedonian medicinal plants

Abstract

Investigations have been made to study the production of phenolic compounds (total phenolics, flavonoids and phenylpropanoids) and total antioxidant capacity in 27 Macedonian traditional medicinal plants to improve its potential as a source of natural antioxidants. Antioxidant potential of plant extracts was analyzed by five different assays: cupric reducing antioxidant capacity (CUPRAC), phosphomolybdenum method (PM), reducing power (RP), 2,2-diphenyl-1-picrylhydrazyl (DPPH·) and 2,2′-azinobis(3-ethylbenzothiazoline-6-sulphonic acid (ABTS·+) radical scavenging activity. Origanum vulgare extract consistently exhibited the highest content of phenolic compounds and the strongest antioxidant capacity based on the tests performed, and can be proposed as a promising source of natural antioxidants. Melissa officinalis and Salvia ringens were also identified as valuable sources of antioxidant compounds. A positive linear correlation between antioxidant activity and total phenolics, flavonoids and phenylpropanoids indicates that these compounds are likely to be the main antioxidants contributing to the observed activities of evaluated plants. These findings suggest that the medicinal plants studied in this paper are good sources of bioactive compounds for the food and pharmaceutical industries.

RP-HPLC/MS/MS Analysis of the Phenolic Compounds, Antioxidant and Antimicrobial Activities of Salvia L. Species

“…Hence there are multiple ways of measuring the antioxidant effect of a source to have complete understanding of the mechanism of action. Furthermore, an extract showing low antioxidant activity could not be labelled as a poor source of antioxidant, since an extract is composed of chemicals with different functional groups and polarities and may behave differently depending on the reaction mixture [50]. We used ethanol as well as water as extraction solvents to dismiss the possibility that some of the polyphenols are not extractable in water due to poor solubility [51].…”

“…The CUPRAC assay is widely used for measurement of the antioxidant capacity of plant extracts, due to the requirements of standard equipment, as well as fast and reproducible results [50]. This assay is based on the measurement of the absorbance of a complex that results from the reaction of antioxidant with Cu 2+ -neocuproine reagent [52].…”

Evaluation of antioxidant capacity of 13 plant extracts by three different methods: cluster analyses applied for selection of the natural extracts with higher antioxidant capacity to replace synthetic antioxidant in lamb burgers

“…These findings are in agreement with those reported by Shan et al (2005) who noticed higher antioxidant activity from oregano extracts (1.01 mmol trolox/g dw) compared with sage (0.52 mmol trolox/g dw), rosemary (0.38 mmol trolox/g dw) and sweet basil (0.30 mmol trolox/g dw) extracts. In addition, Tusevski et al (2014), also observed higher antioxidant activity in extract of Origanum vulgare (714.15 μmol trolox/g dw) than in lemon balm (406.03 μmol trolox/g dw).…”

Antioxidant and α-glucosidase inhibitor activities of natural compounds isolated from Quercus gilva Blume leaves

“…Therefore, antioxidants are considered important because of their many health benefits. Plants such as vegetables, fruits, herbs, and spices contain a wide variety of free radical scavenging molecules, such as phenolic compounds, nitrogen compounds, vitamins, and terpenoids, which have high antioxidant activities [3,4]. In view of these potential health benefits, intensive research has been conducted on natural antioxidants derived from plants.…”