Proc. of
Accumulation of Fluorescent Lipid-Peroxidation
Products During Ripening of ‘Fuerte' Avocado Fruit
Shimon Meir, Sonia Philosoph-Hadas, Giora Zauberman, Yoram Fuchs, Miriam Akerman, and Nehemia Aharoni
Department of Fruit and Vegetable Storage, Agricultural Research Organization, The Volcani Center, P.O. Box 6, Bet Dagan 50250, Israel
Abstract. Fluorescent
products (lipofuscin-like compounds) of lipid peroxidation were extracted from ‘Fuerte’ avocado (Persea
americana Mill.) peels, taken from fruit at different ripening stages and
following storage at 22C in the absence or presence of ethylene. Fractionation
and analysis of these fluorescent compounds (FCs) in
avocado peels was carried out by an improved method, based on separation of FCs from chlorophyll by Sep-Pak silica cartridges. Results
show that accumulation of these fluorescent compounds in avocado peels preceded
by several days the appearance of changes in ripening parameters such as
decrease in fruit firmness, increase in respiration, and ethylene emanation.
Ethylene-treated fruit showed a threefold increase in their FCs
content as compared with untreated fruit. A six-fold increase in FCs level could be detected also in avocado fruit stored
for two weeks at 5C, which did not show any detectable change in the ripening
parameters mentioned above. These data suggest that lipid peroxidation
may be regarded as one of the earliest detectable processes occurring during
fruit ripening. Hence, an increase in FCs in avocado
peel may be employed as a horticultural parameter for estimating initiation of
ripening processes in avocado fruit.