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lead to a substantial increase in the
anthocyanin, fl avonol and proantho-
cyanidin content of grapes through the
induction of enzymes implicated in the
phenylpropanoid biosynthetic pathway;
such compounds may gain interest in the
wine industry by improving grape quality
(Ruiz-García
et al.
, 2012).
Methyl jasmonate treatment of har-
vested loquat fruit followed by cold storage
for 35 days led to a reduced incidence of
chilling injury symptoms, evident as
decreased extractable juice and internal
browning. The alleviation of such
symptoms might be attributed to the sub-
stantial delay of increases in superoxide
radical (O
2
-
˙) production rate and H
2
O
2
content and the higher activities of SOD,
catalase and ascorbate peroxidase (Cao
et al.
, 2009).
affected by storage duration, oxidative
stress, ethylene action/ripening and storage
temperature (Rudell
et al.
, 2011). The
effi cacy of 1-MCP on superfi cial scald
symptoms in Asian pears was attributed to
the induction of catalase and peroxidase
activities but not of SOD activity (Yazdani
et al.
, 2011). 1-MCP treatment proved to be
particularly effective in 'Rocha' pear by
alleviating cold-storage disorders (brown-
ing and superfi cial scald), but without
affecting the free-radical scavenging
activity or the levels of fruit AsA and
glutathione contents. Therefore, it appears
that the effi cacy of 1-MCP is not directly
related to its effects on antioxidant levels
(Silva
et al.
, 2010).
Lately, the effect of 1-MCP on the
antioxidant systems of 'Empire' apple fruit
stored under controlled atmospheres for
prolonged periods has been studied with
special reference to the development of
chilling injury symptoms, evident as
internal browning; however, the data do
not justify a direct role for antioxidant
metabolism during the development of
internal browning (Lee
et al.
, 2012).
1-MCP-treated apricot fruit cold stored
for 3 weeks exhibited a greater resistance to
oxidative stress, postulated as a function of
the lower ion leakage values, higher
antioxidant capacity and higher SOD and
unspecifi c peroxidase activities (Egea
et al.
,
2010). The profi le of individual antho-
cyanins and hydroxycinnamic acids in
'Lambert Compact' sweet cherry was not
affected by cold storage or 1-MCP
treatment, although colour changes were
monitored (Mozetic
et al.
, 2006).
Application of 1-MCP inhibited the
production of H
2
O
2
and specifi c activities
of antioxidant enzymes (catalase, SOD and
ascorbate peroxidase) of cold-stored
'Tainong' mango fruit, suggesting its
putative role in positively regulating the
activated oxygen metabolic balance (Wang
et al.
, 2009a). However, a similar study in
mango fruit showed that 1-MCP treatment
led to decreased levels of H
2
O
2
and lipid
peroxidation, concomitant with increased
activities and isozymes of catalase and SOD
(Singh and Dwivedi, 2008).
7.5.6 Postharvest 1-MCP treatment
The application of 1-MCP is a success story
in the apple fruit industry with benefi cial
effects in terms of quality retention by
inhibition of climacteric ripening re-
sponses, whilst alleviating the chilling
injury symptoms in cold-stored apple fruit.
The effect of 1-MCP treatment on fruit
phytochemical profi le is another emerging
area for future research. Within this area,
Qiu
et al.
(2009) observed that the anti-
oxidant capacity of 1-MCP-treated 'Sunrise'
summer apples after short-term storage at a
range of temperatures (5-22°C) scored
higher values compared with controls.
Furthermore, the application of 1-MCP at
the optimum apple maturity stage has been
proposed as a means of retaining key
fl avonoid compounds during storage and
postharvest ripening (MacLean
et al.
,
2006).
Superfi cial scald is a cold-storage dis-
order of pome fruits attributed to oxidative
stress. Application of 1-MCP or immersion
in an antioxidant agent (diphenylamine)
prevents or alleviates these symptoms. A
recent study identifi ed a key class of
phytosterol metabolites and indicated that
peel phytosteryl conjugate metabolism was
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