posted on 2013-04-24, 00:00authored byPerla
A. Ramos-Parra, Carolina García-Salinas, Carmen Hernández-Brenes, Rocío I. Díaz de la Garza
Folates are essential micronutrients
for humans, and their deficiency
causes several detrimental effects on human health. Papaya fruit is
an important natural source of some micronutrients. This paper presents
a first complete characterization of folate derivatives accumulated
in cv. Maradol papaya during fruit development and ripening processes.
During postharvest ripening, the fruit accumulated up to 24.5% of
the daily folate recommended dietary allowance (RDA) for an adult
in a 1 cup (145 g) portion. Tetrahydrofolate (THF) and 5-methyl-THF
were the predominant folate classes observed. Surprisingly, an unusually
long polyglutamylation profile of tentatively up to 17 glutamates
linked to 5-methyl-THF was detected; to the authors’ knowledge,
this very long polyglutamyl tail has not been reported for any organism,
and it is probably characteristic of this plant species. This polyglutamylation
degree changed throughout fruit development and ripening, showing
the largest differences at the onset of ripening. This work raises
questions about the functional role of folate derivatives in fruit
development.