Enrichment of Olive Fruits in Antioxidant Content by Pre-Harvest Salicylic Acid Treatment

We here study the effect of the pre-harvest application of salicylic acid at two different concentrations on the olive phenolic composition. Influence of the cultivar and harvesting day were considered. As a result, the total phenol content increased significantly, particularly when using 200 mg mL(−1) of salicylic acid. However, the free radical scavenging activity was cultivar dependent. For instance, when the olives were harvested on day 3 and treated with 200 mg mL(−1) of salicylic acid, the antioxidant activity decreased from 161 to 278 µg mL(−1) for Arbequina, whereas it increased from 397 to 258 µg mL(−1) for Picual. Generally speaking, oleuropein and hydroxytyrosol contents enhanced with the application of 200 mg mL(−1) of salicylic acid. The results found suggest that exogenous salicylic acid is an interesting agronomic practice to enrich olive fruits in antioxidants.