Identification and Assessment of Antioxidant Capacity of Phytochemicals from Kiwi Fruits

Abstract

The kiwi fruit is the edible berry of a cultivar group of the woody vine of several Actinidia species. The most common commercially available, green-fleshed kiwi fruit is the cultivar 'Hayward', which belongs to the Actinidia deliciosa species. An antioxidative screening of kiwi fruit components (peel and pulp) crude extracts was carried out using specific assay media characterized for the presence of highly reactive species such as 2,2'-diphenyl-1-picrylhydrazyl radical (DPPH(•)), H(2)O(2), and O(2)(•-). The Mo(VI) reducing power of the samples was also determined. The phenol and flavonoid contents were quantified. Phytochemical analysis of kiwi peel crude extracts led to the isolation of vitamin E, 2,8-dimethyl-2-(4,8,12-trimethyltridec-11-enyl)chroman-6-ol, as well as α- and δ-tocopherol, 7 sterols, the triterpene ursolic acid, chlorogenic acid, and 11 flavonoids. Chemical fractionation of pulp crude extracts led to the isolation of two caffeic acid glucosyl derivatives and two coumarin glucosydes, besides the three vitamin E, β-sitosterol, stigmasterol, and its Δ(7) isomer, campesterol, chlorogenic acid, and some flavone and flavanol molecules. All of the compounds were tested for their radical scavenging and antioxidant capabilities by measuring their capacity to scavenge DPPH and anion superoxide radical and to reduce a Mo(VI) salt.

Effect of summer pruning on some fruit quality traits in Hayward kiwifruit

“…Summer pruning of kiwifruit vines, complementary to winter pruning, improves light distribution within the canopy, reduces the competition between the actively growing shoots and young developing fruitlets, and increases assimilate partitioning to the fruiting canes [4,5]. Fruit antioxidant components change with species, cultivar [6,7], environmental conditions, orchard management, fruit ripening stage and length of postharvest fruit storage [8,9]; little is known about kiwifruit variability in terms of antioxidant capacity [10,11]. Light distribution within the canopy can also play a role in fruit mineral composition [12] and total antioxidant capacity of fruits [13,14], which in 'Hayward' kiwifruits is strongly due to their content of ascorbic acid and R-tocopherol, that account for 40% of the fruit antioxidant capacity [15].…”

Beneficios nutricionales y sanitarios asociados al consumo de kiwi

“…Además, el kiwi contiene otras sustancias como son la vitamina E, luteí-na, zeaxantina y fitoquímicos, muchas de ellas con propiedades antioxidantes (12).…”

Actinidia callosapeel (kiwi fruit) ethanol extracts protected neural cells apoptosis induced by methylglyoxal through Nrf2 activation

“…Kiwi fruits (Actinidia callosa) contain a large amount of polyphenolic acid (Barberis et al, 2012) and show antioxidation activity (Fiorentino et al, 2009). Recently, A. callosa has been reported to down-regulate blood glucose and inhibits 3T3-L1 pre-adipocyte differentiation (Abe et al, 2010;Shirosaki et al, 2008).…”