Introduction. Cashew apple
is a rich source of sugars, vitamin C and polyphenols. In spite
of its nutritional value, this pseudo-fruit has been left unexploited
to a large extent in the crop-growing areas. Some reports of the
chemical characteristics of cashew apple have been published. However,
nothing is known about the changes in the composition of its bioactive compounds
in the course of ripening. Materials and methods. Cashew
apples at three different maturity stages were examined with respect
to their ascorbic acid content, phenolic compounds and antioxidant
capacity. Ascorbic acid was quantified by HPLC. Phenolic compounds
were identified and quantified by using HPLC-ESI-MS/MS by comparison
with authentic standard compounds. The antioxidant capacity was
measured by TOSC assay against peroxyl radicals and peroxynitrite.
Results. Amounts of identified phenolic compounds were
the highest in unripe cashew apple and decreased in the course of
ripening. Myricetin 3-O-rhamnoside, quercetin 3-O-galactoside and quercetin
3-O-rhamnoside turned out to be the main flavonoids in all maturity
stages. The antioxidant capacity and the concentration of ascorbic
acid increased in the course of ripening. The antioxidant activity
was considerably influenced by ascorbic acid, more than by the content of
phenolic compounds. Conclusion. This study provides, for
the first time, information on changes in bioactive compounds and
the antioxidant capacity in cashew apple during ripening. A dietary
or technological exploitation of ascorbic acid is useful in the
ripe condition. The unripe pseudo-fruits are a good source for the extraction
of polyphenols with regard to possible food technological purposes
or the preparation of food supplements.