Variations in essential oil production and antioxidant system of Ocimum gratissimum after elicitation

Ocimum gratissimum L. is appreciated for its condiment and medicinal properties. Its essential oil has antifungal and antioxidant activity, being valuable for pharmaceutical and commercial applications. However, plants usually do not produce a large amount of essential oil. In this sense, studies have been conducted to shown that it is possible to increase essential oil synthesis through elicitation. Therefore, the aim of this work was to use the elicitor Salicylic acid (SA) on O. gratissimum to enhance its essential oil production. Plants were subjected to elicitation treatment with SA solutions of 0, 0.5, 1.0 and 1.5 mM. Fresh leaves were used for essential oil extraction after 10 days of elicitation, and antioxidant system analysis was performed throughout this period. Elicitation with SA promoted an increase in the percentage content of O. gratissimum essential oil by 39.8% compared to control plants. An increase of 4.2% in eugenol, its major compound, was also observed. Additionally, changes in signaling defense response were detected in elicited plants. There was an increase in enzymes activity, Superoxide Dismutase and Catalase, and also the content of hydrogen peroxide and lipid peroxidation were higher in elicited plants. Therefore, the elicitation with SA influenced O. gratissimum antioxidant system and its essential oil production.