Chemical composition, antioxidant and allelopathic activities of essential oil of salvia officinalis L.

This study assessed the chemical composition, antioxidant and allelopathic activities of essential oil of Salvia officinalis L. Twenty-eight compounds were found (corresponding to 98.82% of the essential oil). The majors compounds were: camphor (27.59%), camphene (23.70%), α-pinene (13.75%), β-pinene (6.28%), and limonene (5.38%). Monoterpenes (68%) predominated in the essential oil. The essential oil exhibited 85.3% of DPPH radical scavenging activity and the IC50 value was 3.67 µg/mL, which characterized this oil as a great antioxidant.The essential oil was tested at concentrations of 0, 100, 200, 400, 600, 800, 1000, and 2000 mg/L (w/v) to assess the allelopathic effect on germination of tomato (Lycopersicum esculentum Mill.), guinea grass (Panicum maximum Jacq.), and chia (Salvia hispanica L.). The final germination percentage of the three species was not inhibited by the essential oil at the concentrations tested. However, the germination speed index, time, and germination rate were adversely affected in most concentrations tested, with a significant difference in comparison with the control treatment for tomato and chia seeds. The same behavior was not observed for guinea grass seeds.