Prickly Pear Fruit and Cladodes - Crop Post-Harvest: Science and Technology - page 302

et al . 1994). These positive health effects of Opuntia
stems might be associated to dietary fibres, since similar
results can be achieved by Plantago psyllium or other
sources of dietary fibres (Frati 1992). Ethanol extract of
Opuntia ficus-indica shows potential analgesic and anti-
inflammatory effects (Park et al . 1998). Ingestion of raw
and cooked Opuntia ficus-indica extracts presents benefi-
cial effects on growth and total cholesterol, without any
secondary effect on glucose and lipoproteins amounts in
blood (Medellin et al . 1998).
The consumption of prickly pear fruits is recommended
for their beneficial and therapeutic properties (Barbera &
Inglese 1993). Recently there has been a surge in interest in
Opuntia because of nutritional and health benefits, including
among others, improving platelet function (Wolfram et al .
2003); reducing blood lipid and total cholesterol, low-
density lipids and triglycerides (Wolfram et al . 2003; Wolfram
et al . 2002; Palumbo et al . 2003); lowering isoprostane con-
centrations in blood indicating lower oxidative injury
(Budinsky et al . 2001); antiulcerogenic activity (Galati et al .
2003a, 2003b) and as a source of antioxidants (Butera et al .
2002). Aqueous extracts of cactus pear ( O. ficus-indica
L. Mill) possess a high total antioxidant capacity, expressed
as trolox equivalents, and exhibit a marked antioxidant
capacity in several in vitro assays, including the oxidation of
red blood cell membrane lipids and the oxidation of human
LDLs induced by copper and 2,2′-azobis(2-amidinopro-
pane-hydrochloride) (Butera et al . 2002). Antioxidant com-
ponents reported by these authors included vitamin C,
negligible amounts of carotenoids and vitamin E and no
polyphenols. The fruit of some types of prickly pear contain
2 betalain pigments, the purple-red betanin and the yellow
indicaxanthin, both with radical scavenging and reducing
properties (Forni et al . 1992; Fernandez-Lopez & Almela
2001; Stintzing et al . 2002). Daily supplementation with
500 g cactus fruit ( O. ficus-indica ) pulp for 2 weeks greatly
improved the oxidation stress status of healthy humans
(Tesoriere et al . 2004). The effects included remarkable
reduction in plasma markers of oxidative damage to lipids,
such as isoprostanes and malondialdehyde (MDA), an
improvement in the oxidative status of LDL, considerably
higher concentrations of major plasma antioxidants, and
improvement in the redox status of erythrocytes. The nutri-
tional and health benefits of cactus fruit are believed to stem
from their alleged antioxidant properties related to ascorbic
acid, phenolics including flavonoids, and a mixture of yel-
low betaxanthin and red betacyanin pigments (Galati et al .
2003b; Gurrieri et al . 2000; Tesorieri et al . 2003). Total anti-
oxidant activity of differently coloured cactus fruit (nine
Opuntia ficus-indica clones and one O. robusta clone)

(measured by Trolox-equivalent antioxidant capacity TEAC,
and oxygen radical absorbance capacity, ORAC, assays)
were very highly correlated among each other and also with
total phenolic contents, betalains contents and ascorbic acid
concentrations (Stintzing et al . 2005). Total phenolic content
had the greatest contribution to ORAC and TEAC values.
Total antioxidant activity measured by six assays highly cor-
related with the content of vitamin C (Corral-Aguayo et al .
2008). However, these correlations would depend on many
factors such as the different type of cactus, growing region,
harvesting time and so on. Generally, nutritional and health
benefits of the different cactus fruit can be contributed by
diverse components such as pigments (Butera et al . 2002;
Tesoriere et al . 2003), colourless phenolic compounds
(Galati et al . 2003b; Kuti, 2004; Pellegrini et al . 2003),
mucilages, fibres and other constituents (Stintzing et al .
2001, 2005; Gurrieri et al . 2000).
Reports indicate that other parts of this plant are also
used in folk medicine as emollient, moisturizing, cicatri-
zant, hypocholesterolemic, hypoglycemic agent and in
gastric mucosa diseases (Cruse 1973; Meyer & McLaughlin
1981; Harvala et al . 1982; Camacho-Ibanez et al . 1983;
Brutsch 1990; Frati et al . 1990a; Hegwood 1990; Pimienta
1990; Fernandez et al . 1992, 1994; Rosado & Diaz 1995).
In Sicilian folk medicine, a flower infusion has an effect
generally defined as depurative, and in particular it is used
because of its diuretic and relaxant action on the renal
excretory tract (Arcoleo et al . 1961, 1966; Sisini 1969).
Therefore, it is stipulated that a flower infusion may help
the expulsion of renal calculus. The fruit also enhances
renal function (Cacioppo 1991). Galati et al . (2002)
reported that flower infusion shows a modest increase in
diuresis and natriuresis. Treatment with cladode infusions
increases diuresis but does not significantly influence the
uric acid pattern. The fruit infusion instead had diuretic and
antiuric activity. The diuretic action observed may depend
on stimulation of the urinary tract and is linked to the acti-
vation of neurohumoral mechanism, mediators of stimuli
acting on glomerules, tone acid on the pyelo-uretral peri-
staltis. These effects might be due to the influence that the
electrolytes, present in considerable quantities on the plant,
exert on renal epithelium. In particular, O. ficus-indica is
rich in K + ions, which are present in concentration of
548 mg kg ¯ 1 in the cladodes, 21.7 mg kg ¯ 1 in the flowers
and 18 mg kg ¯ 1 in the fruit (d'Aquino 1998). Galati et al.
(2001) reported preventive and curative effects of O. ficus-
indica Mill. cladodes preparations on rats affected by etha-
nol-induced ulcers. The cactus consumption gives rise to
cytoprotection phenomena by breaking up the epithelial
cells and stimulating an increase in mucus production.