Background:
Phospholipase D (PLD)is closely related to browning and senescence of
postharvest longan fruit.
Objective:
This study investigated the effects of 2-butanol (a PLD inhibitor) on the expression and
regulation of PLD during storage of longan fruit at a low temperature.
Methods:
Senescence-related quality indices showed that the 2-butanol-treated fruit presented lower
pericarp browning index, pulp breakdown index and total soluble solid value than the untreated
fruit.
Results:
The fruit treated by 60 µL/L 2-butanol exhibited the strongest inhibition on senescence,
which significantly delayed changes in weight, titratable acidity content, total soluble solid content
and ascorbic acid content. This treatment maintained a high level of total phenolic content and
caused significant inhibition on pericarp browning and pulp breakdown. Through ELISA method,
60 µL/L 2-butanol treatment also reduced PLD activity. Real-time RT-PCR (RT-qPCR) results
showed that PLD mRNA expression level was inhibited by 60 µL/L 2-butanol within 15 days.
Western-blotting results further confirmed the differential expression of PLD during storage, and a
relatively higher expression for PLD protein was found in control compared to the 2-butanoltreated
fruit during 15-d storage.
Conclusion:
These results provided a scientific basis and reference to further investigating postharvest
longan quality maintenance by regulating the PLD gene expression.
Activation of phospholipase D by calmodulin antagonists and mastoparan in carnation petals
