Effect of ethylene treatment on kiwifruit bioactivity.
The consumption of fruits and vegetables with high antioxidant activities leads to best healthful results. Therefore, in the present investigation we tried to find the peak of the kiwifruits antioxidant activity during the first 10 days of ethylene treatment (100 ppm at 20 degrees C). In order to receive the most reliable data five different antioxidant assays were used: ferric-reducing/antioxidant power (FRAP); cupric reducing antioxidant capacity (CUPRAC); trolox equivalent antioxidant capacity (TEAC); 1, 1-diphenyl-2-picrylhydrazyl radical (DPPH); and Folin-Ciocalteau. It was found by all applied methods that kiwifruit samples have the highest contents of polyphenols and flavonoids and the highest antioxidant activity on the 6-th day of the ethylene treatment. The correlation coefficients between polyphenols, flavonoids and antioxidant activities of kiwifruit methanol extracts with TEAC and CUPRAC, were as followed: 0.81 and 0.63, and 0.23 and 0.17, respectively, and showed that the free polyphenols correlation coefficients were higher than that of the flavonoids.


CONCLUSIONS
during ethylene treatment the bioactivity of kiwifruit is increasing and reaches its maximum at the 6th day and therefore it is the optimum time for kiwifruit consumption; total polyphenols were the main contributor to the overall antioxidant activity of kiwifruit; the most sensitive test for antioxidant activities determination is FRAP.
Park
Yong-Seo
YS
Department of Horticultural Science, Mokpo National University, Muan Jeonnam, Korea.
Jung
Soon-Teck
ST
Kang
Seong-Gook
SG
Delgado-Licon
Efren
E
Katrich
Elena
E
Tashma
Zev
Z
Trakhtenberg
Simon
S
Gorinstein
Shela
S
D029042:Actinidia / Q000737:chemistry / Q000187:drug effects*; D000975:Antioxidants / Q000032:analysis / Q000737:chemistry* / Q000378:metabolism*; D005030:Ethylenes / Q000494:pharmacology*; D005419:Flavonoids / Q000032:analysis / Q000737:chemistry / Q000378:metabolism; D006801:Humans; D009753:Nutritive Value; D010084:Oxidation-Reduction; D010636:Phenols / Q000032:analysis / Q000737:chemistry / Q000378:metabolism; D010937:Plant Growth Regulators / Q000494:pharmacology*; D059808:Polyphenols; D013997:Time Factors
D000975:Antioxidants; D005030:Ethylenes; D005419:Flavonoids; D010636:Phenols; D010937:Plant Growth Regulators; D059808:Polyphenols; C036216:ethylene