The influence of organic/integrated production on the content of phenolic compounds in apple leaves and fruits in four different varieties over a 2-year period.
BACKGROUND
Phenolics in fruit may be influenced by the fruit type, cultivation conditions of a plant, climatic conditions, growing season, storage conditions, and industrial processing. The aim of this study was to compare single phenolic compounds, total phenolics and antioxidant capacity of four varieties of apple grown under organic and integrated conditions over a 2-year period.


RESULTS
Several different phenolic compounds belonging to the groups of hydroxycinnamic acids, flavanols, dihydrochalcones, flavonols and anthocyanins were quantified. The levels of all analysed groups of phenolics were higher (not always significantly) in the organically grown apple leaves and fruit than in the leaves or apples from integrated production. Leaves from organic trees had 10-20% higher content levels of total phenols than the leaves from trees in the integrated growing system. In both years, organic production affected the increase in the antioxidant activity of apple peel. Organic apples have higher total phenolic content than the integrated grown ones.


CONCLUSIONS
Cultivation type had an important influence on the polyphenolic level and antioxidant capacity of the apple fruits and leaves. Apples from organic production showed a higher content of hydroxycinnamic acids, flavanols, dihydrochalcones, quercetins and total phenolics than apples from integrated cultivation.
Mikulic Petkovsek
Maja
M
Biotechnical Faculty, Agronomy Department, University of Ljubljana, SI-1000 Ljubljana, Slovenia. maja.mikulic-petkovsek@bf.uni-lj.si
Slatnar
Ana
A
Stampar
Franci
F
Veberic
Robert
R
D000975:Antioxidants / Q000032:analysis*; D005419:Flavonoids / Q000032:analysis*; D058870:Food, Organic / Q000032:analysis*; D005638:Fruit / Q000737:chemistry*; D027845:Malus / Q000737:chemistry* / Q000145:classification / Q000254:growth & development; D058871:Organic Agriculture / Q000379:methods; D010636:Phenols / Q000032:analysis*; D018515:Plant Leaves / Q000737:chemistry; D059808:Polyphenols; D013045:Species Specificity
D000975:Antioxidants; D005419:Flavonoids; D010636:Phenols; D059808:Polyphenols