1. Gumul, D.*; Kruczek, M.**; Ziobro, R.; Ziec, G.; Berski, W.
The content of phenolic compounds in different buckwheat lines
Gumul, D.*; Kruczek, M.**; Ziobro, R.; Ziec, G.; Berski, W.
Department of Carbohydrate Technology, Faculty of Food Technology, University of Agriculture in Krakow, Krakow, ul. Balicka 122, Poland
ABSTRACT
Among grain-like seeds buckwheat has a special place in view of its health benefits. Buckwheat has a higher antioxidative activity than other cereals, because it contains the broad spectrum of polyphenols, particularly flavonoids. It is not surprising then, that there is a growing interest in obtaining new buckwheat lines and cultivars.
Table 2 Total Flavonoids Content of different lines of buckwheat
Samples
TFC (mg rutin/ g dm)
PA-13
6,96±0,09
PA-14
6,39±0,07
PA-15
5,76±0,07
PA-16
6,32±0,13
21/2002
5,60±0,23
5/2006
5,55±0,32
6/2006
6,20±0,18
8/2008
6,57±0,12
13/2008
5,61±0,08
Figure 1 Total antioxidant activity of different lines of buckwheat
Samples
%RSA
PA-13
97,81%
PA-14
98,35%
PA-15
PA-16
97,88%
21/2002
98,50%
5/2006
83,35%
6/2006
77,96%
8/2008
98,90%
13/2008
AIM
The aim of this research work was to study total polyphenol content, flavonoids content and antioxidant activity of different buckwheat lines.
MATERIALS AND METHODS
Study material consisted of nine lines of buckwheat, cultivated in Mazury in Poland. The samples were analyzed for free polyphenols, free and bound polyphenols, and content of flavonoids. Antioxidant activity was also studied by spectrophotometric measuring of synthetic free radicals ABTS·+(2,2'-azino-bis(3-ethylbenzthiazoline-6-sulphonic).
Abbreviations: TFC- Total Flavonoids Content
RESULTS
Table 1 Total Polifenolic Content of different lines of buckwheat
Samples
TPC (mg catechin/g dm)
methanol and acetone extracts
ethanolic extracts
PA-13
6,96±0,85
6,52±0,23
PA-14
6,39±0,07
5,47±0,22
PA-15
5,76±0,07
4,84±0,06
PA-16
6,32±0,13
5,24±0,26
21/2002
5,60±0,23
5,44±0,06
5/2006
5,55±0,32
5,05±0,15
6/2006
6,20±0,18
5,49±0,07
8/2008
6,57±0,12
5,11±0,11
13/2008
5,61±0,08
4,96±0,07
Abbreviations:
TPC- Total Polifenolic Content
dm- dry matter
Abbreviations:
%RSA- Radical Scavenging Activity
ABS0- absorbance of DPPH (2, 2-diphenyl-1-picrylhydrazyl ) radical + ethanol
ABS6 min- absorbance of DPPH radical + buckwheat exctract after 6 min
Results are means ± standard error
CONCLUSIONS
The highest content of free and bound polyphenols among the investigated buckwheat lines was found in the PA13 line, but the observed differences were not statistically significant. PA13 line has been characterized by the highest content of free polyphenols compared to other buckwheat lines, and the result varied in a statistically significant way.
The lowest content of free and bound polyphenols among the investigated buckwheat lines were found in the samples: PA15; 21/2002; 5/2006; 13/2008. While the content of free polyphenols were the smallest in samples: PA15 and 13/2008. Line PA13 has been characterized as having the highest content of flavonoids, whilst the lowest content was found in the samples: PA15; 21/2002; 5/2006; 13/2008.
It was observed that, the lowest content of antioxidant activity was found in line: 6/2006 and the highest in line: 8/2008. The highest content of free and bound polyphenols, free polyphenols and total flavonoids in the line PA13 did not guarantee high antioxidant status of its buckwheat line.
Additionally the differences of antioxidant activity between new lines were small, but in spite of that the antioxidant activity were still very high.