Polyphenol content and antiradical activity in different apple varieties

Abstract

Polyphenols are important antioxidant constituents of apples and they contribute positively to human health because they possess an antiradical activity. Fifteen apple varieties were analysed for their total polyphenol content (TP) by two methods -by Folin-Ciocalteau reagent (FC) and by EBC method with carboxylmethylcellulose/sodium ethylendiamintetraacetate (CMC/EDTA) and their antiradical activity (ARA) by DPPH method using stable free radical 1,1-diphenyl-2-picrylhydrazyl (DPPH·). TP and ARA were determined in freshly expressed apple juice and apples and obtained results were statistically evaluated. The differences between varieties were significant. The correlation between TP content determined by FC method determining all free aromatic hydroxyls and EBC method determining mainly ortho-aromatic hydroxyls was found with r = 0.73. The highest differences among analysed varieties were found for ARA values in both, juice and apples and for TP content determined by FC in apples. High polyphenol content was found in Jonagold, Jonalord, Melodie and Melrose varieties both, in apples and juices; on the contrary low TP contents were estimated in Gloster and Rosana varieties. The highest ARA levels were found in Rajka, Bohemia and Melrose varieties, compared to low ARA levels found in apple fruits of Šampion and Topaz varieties. phenolic acids, and flavonoids and correlated well with polyphenols and flavonoids (0.9207) (Leontowicz et al. 2003). Also Lee et al. (2003) confirm that flavonoids such as quercetin, epicatechin, and procyanidin B-2 rather than vitamin C contribute significantly to the total antioxidant activity of apples. A highly linear relationship (R 2 > 0.97) was attained between concentrations and total antioxidant capacity of phenolics and vitamin C. Among individual compounds the estimated contribution of major phenolics and vitamin C to the total antioxidant capacity of 100 g of fresh apples expressed in vitamin C equivalent antioxidant capacity (VCEAC) was: quercetin (40.39) > epicatechin (23.10) > procyanidin B-2 (22.07) > vitamin C (12.80) > phloretin (9.11) > chlorogenic acid (8.75). In apples five major polyphenolic groups with the total of sixteen individual compounds were found, among which the dihydroxycinnamic acid esters, phloretin glycosides, and flavan-3-ols were found in both flesh and peel, whereas quercetin glycosides were almost exclusively found in the peel (Tsao et al. 2003). In both apple peel and flesh, the predominant group of polyphenolics was the procyanidins, followed by quercetin glycosides in the peel and hydroxycinnamic acid esters in the flesh. Compared to the pulp of the apples, skin-extracts show a higher antioxidant potential (Schirrmacher, Schempp 2003). Wolfe et al. (2003) confirmed that within each variety, the total phenolic and flavonoid contents were significantly the highest in the peels, followed by the flesh. As Chinnici et al. (2004) discovered, among the single classes of compounds, procyanidins (in peels and pulps) and flavonols (in peels) statisti...

Chemical Composition, Antioxidant Capacity, and Sensory Quality of Dried Sour Cherry Fruits pre-Dehydrated in Fruit Concentrates

“…In the other two assays, the antioxidant activity in the concentrates before the OD process differed significantly but showed the same relative ranking. The antioxidant activity determined by means of FRAP and ORAC assays ranged from 1.14 and 3.14 mmol (apple) to The antioxidant activity was consistent with the characteristics of the fruits from which the concentrates were obtained and with the literature data (Wojdyło et al 2013a;Ou et al 2002;Kołodziejczyk et al 2013;Lachman et al 2006;Oszmiański and Wojdyło 2005;Tsuneya et al 1983). After 90 min of the OD process, a significant (p<0.05) drop in antioxidant activity was noticed in all the analyzed solutions, except for the sucrose solution and apple concentrate.…”

“…The color of the sour cherries is an important quality trait, and it is modulated by anthocyanins. Sour cherries have a relatively high anthocyanin content, compared with red berries and other fruits (Blando et al 2004;Wojdyło et al 2013aWojdyło et al , 2014bLachman et al 2006;Oszmiański and Wojdyło 2005). Dehydration processes often affect color quality in foods, thus reflecting a loss of anthocyanins and other phytochemicals specific to fruits, vegetables, and herbs (Lin et al 1998).…”

Antioxidant Activity and Phenolic Content of Apple Cider

“…Total phenolic contents of AS and CAM samples were 459.31 mg/L and 1026.74 mg/L, respectively (Figure 3). Lachman et al (2006) determined that total phenolic content of apple juice samples obtained from different varieties were between 760.03-1343 mg/L. In our study, total phenolic content of ASM and AS samples were 777.83 and 733.61 mg/L.…”

Rootstock genotype determines phenol content in apple fruits

“…Several times more phenolic compounds are found in the peel than in apple flesh (Wolfe et al 2003, Drogoudi et al 2008, Leccese et al 2009). High content of phenols was detected in apple juices as well (Lachman et al 2006). In our trial, we examined a whole fruit.…”