Ultrasound-assisted extraction of total phenols and flavonoids from dry tobacco (Nicotiana tabacum) leaves.

Yields of extracted substances, as well as total phenol and flavonoid compounds obtained by classical and ultrasonic extractions from dry leaves of two tobacco types (oriental and Virginia) by two different solvents (acetone and methanol) at two operating temperatures (25 and 40 degrees C) were compared. The yield of extractive, as well as total phenol and flavonoid compounds depended on the type of solvent, operational temperature and the tobacco type. The importance of these factors was assessed using 2(4) full factorial experiments without replication.