Take your samples into R.B. attach it with condensor and boil on water bath upto 2 hrs. After cooling filter it and then concentrate the filtrate. Now you will have extract.

see these paper please contains 6 approaches of extraction

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4446625/

regards

Rotatory evaporator can be a suitable option

Powder the sample in very small size (less than 100 microns). then 2- 3 hr stirring with the solvent in hot plate.