Firstly, powders of tomato leaves (5g) were dissolved in an
appropriate volume of ethanol. Then the extraction were
carried out using NJC equipment, microwave power, extraction
time, temperature and ratio of raw material-to-solvent (g/ml)
were recorded in the whole process. When the extraction was
completed, the system were cooled to room temperature with
cold water and filtered. Then, the entire extract was transferred
to a 1000 ml volumetric flask, and the reaction vessel was
rinsed 3 times with 50 ml of ethanol each. The above procedure
was repeated three times. Finally, the extract in ethanol was
evaporated under reduced pressure at 50OC. The residue was
weighed and analyzed. The extraction yield was calculated as
follows: the content of solanesol in the extract / the content of
solanesol in the powders × 100%. The content of solanesol = the
weight of the extract or powders × the HPLC purity of solanesol.
The MAE conditions were optimized according to an
orthogonal design [L16 (44)] as shown in Table 1. All of
experiments were repeated three times