The preparation of N. speciosa flower extraction and nanoencapsulation (Naufalin and Herastuti, 2013). N.
speciosa flowert powder was extracted twice with ethanol (1:4 w / v). The extraction process is done by maceration
at 37°C, with a rotation speed of 150 rpm for 24 hours every level. Filtrat separated from the solvent by evaporation
in a rotary evaporator until no solvent dripping again. The solvent was evaporated at a temperature of 50oC.
Residual solvent is removed with nitrogen gas to produce an essential oil (Naufalin et al., 2013).