|Authors: ||A. Hajdari, B. Mustafa, CH. Franz, J. Novak|
|Keywords: ||DPPH, FRAP, antioxidant activity, Betonica officinalis, wood betony|
Betonica officinalis (Lamiaceae) commonly known as purple betony or wood betony has a wide variety of free radical scavenging molecules, like flavonoids, phenolic compounds, etc., making the species an interesting candidate as a natural antioxidant.
To study the natural variability of the antioxidant activity and compound groups related to this activity (flavonoids, phenolics) leaves and roots of three populations of B. officinalis were collected from different localities in Kosovo.
First locality was a location in Malet e Sharrit national park (Mushtisht), the second was a location near a main road (Duhle) and the third was located close to a power plant (Gazimestan). The extraction was made with methanol.
Total flavonoids, total phenolics and two anti-oxidative tests (DPPH and FRAP) were performed by spectrophotometric methods.
The total phenolics ranged from 22.86 to 80.50 mg caffeic acid/g dm, whereas total flavonoid contents ranged between 9.63 and 39.70 mg catechin/g dm.
Concentration of total phenolics and total flavonoids in leaves was about 3-fold more than in roots.
Consequently the highest antioxidant activity was found in leaves, than in roots (about 2.5-fold for DPPH; and: 2.8-fold for FRAP). Total flavonoids differences between the localities were not significant for both leaves and roots.
Regarding the total phenolics in leaves the population from Duhle differed significantly from the two other populations.
DPPH activity in leaves, however, was significantly higher in the locality Gazimestan, whereas FRAP activity in the Duhle locality.
Total flavonoids, total phenolics and antioxidative activity (DPPH and FRAP) of roots did not show any significant difference between the localities.
The concentrations of the flavonoids and phenolic compounds in the leaves showed a very high positive correlation in both antioxidative systems.
In the roots, different compound groups seem to participate to the antioxidant activity.
Download Adobe Acrobat Reader (free software to read PDF files)