Total wax and n-alkane profiles from fruit and leaf waxes of Malpighia glabra L.

Abstract

Malpighia glabra L., popularly known as "acerola" or Barbados cherry, is an economically important species due the high levels of ascorbic acid (vitamin C) in its fruits. Cuticular wax affects post-harvest storage. Nevertheless, no data are available for wax composition on this species. Crude wax amount and n-alkane profiles have been evaluated for three distinct genotypes of acerola. The total amount of wax ranged from 11 µg.cm-2 to 24 µg.cm-2 on leaves and 10 µg.cm-2 to 30 µg.cm-2 on fruits. Two of the three genotypes presented statistically distinct totals for leaf and fruit-wax. Type A (yellow epicarp) presented the highest amounts of crude wax on both leaves and fruits. n-Alkanes ranged from C18 to C34 in fruits, with n-pentacosane (C25) as the main homologue of most individuals. Narrower n-alkane distribution was found in cuticular foliar wax, with C22-C33, with n-hentriacontane (C31) as the major component of most individuals. The environmental and economical aspects related to total wax amounts and n-alkane profiles are discussed herein.