Antioxidants and Bioactive Compounds in Fruits - Fruit Ripening: Physiology, Signalling and Genomics - page 109

the data generated by laboratory methods
to in vivo (human) effects, and clinical
trials to test benefi ts of dietary antioxidants
have produced mixed results. Antioxidant
molecules in food have a wide range of
functions, many of which are unrelated to
the ability to absorb free radicals.

minor economic importance. Recently,
these fruits have received signifi cant
attention due to their superior phyto-
chemical profi les and antioxidant potency
(Pantelidis et al. , 2007; reviewed by
Szajdek and Borowska, 2008). Another
review work described the principal bio-
active compounds of berry fruits and
subsequent infl uence of growth conditions.
This work also offered the possibility of
new genotypes selected for enhanced
phytochemical content (Battino et al. ,
2009). The benefi cial health properties of
berry fruits are partly associated with the
presence of relatively high levels of
phenolic compounds (Seeram et al. , 2006).
Other 'forgotten' berries, such as sea
buckthorn ( Hippophae rhamnoides L.) are
currently of particular interest for their
high healthy phytochemical content of, for
example, tocopherols and tocotrienols. It
should be noted that the concentration of
such compounds is cultivar specifi c and
highly dependent on harvest date, while
seasonal year-to-year differences have been
monitored (Andersson et al. , 2008).
Pome and stone fruits are the most
extensively studied temperate fruit crops
because of their value in the marketplace.
Presently, fruit quality retention after
harvest is also perceived in terms of bio-
active compound content. This is particu-
larly important when new peach and apple
cultivars are launched into the market-
place. The main polyphenols in apples
are catechin, epicatechin, chlorogenic
acid, phloridzin, quercetin-3-glucoside,
quercetin-3-rhamnoside, kaempferol-3-
glucoside and procyanidins B1 and B2.
Measurement studies have shown a
relatively high content of such compounds
in indigenous or 'forgotten' cultivars.
Whilst apple has been studied adequately
in terms of its phytochemical profi le, a
scarcity of information exists regarding
other pome fruits, primarily pear. As
European and Japanese pears are also
characterized by different ripening
patterns, there is an emerging need to
clarify

7.4 Fruits as Reservoirs of
Antioxidants

Over the last decade, numerous screening
studies have monitored the antioxidant
profi le and phenolic, carotenoid and
vitamin C contents in an array of fruits at
their commercial maturity stage. Such
studies have focused on the genotype
variation among cultivars of the same
species grown under similar environmental
conditions and subjected to common
agricultural practices. Epidemiological
studies have already documented an
inverse association between fruit con-
sumption and chronic diseases, such as
different types of cancer and cardio-
vascular disease. In promotion of the con-
sumption of fresh horticultural products,
the fi ve-a-day campaign substantially
helped to deliver the message of a healthy
diet based on fruit consumption (Havas et
al. , 1994; Sorensen et al. , 1999).
Modern crop breeding has developed
many tomato cultivars with increased yield
performance, disease tolerance and ex-
tended shelf-life, paying little attention to
qualitative traits such as fl avour, nutrition
and human health (Dorais et al. , 2008). $
recent study compared the bioactive
content and antioxidant potency of tomato
cultivars with high lycopene content
during different maturity stages (green,
green-orange, orange-red and red-ripe) with
'Rio Grande', a common cultivar (Ilahy et
al. , 2011).
Determination of phytochemical profi les
has led to the reconsideration of some
overlooked commodities such as small
fruits (blackberries, blueberries, goose-
berries, red currants) based on their size
and also possibly due to their relatively

their phytochemical content

fl uctuations during storage.