sorry i forgot an important step - to dessicate the solid formed when adding NaHCO3 n' Na2SO4 before putting on soxhlet to extract with hexane... well i sad that i'd translate it and post here but it is 5 pages and and its not good. the main is:
they extract the rb with tartaric alcohol by maceration and shakes for 48h, filter. reduce the volume of the filtrate add NaHCO3 (excess) and Na2SO4 ,dessicate the stuff. make a soxhlet extrac. with ether evap. the solvent dissolved in dil.HCL adjust pH to 5-6, filter and make tests in rats.
the problem that i can see is to use ether in final extraction -carrying some polar compounds- and they don't defat first. the final product is a little crude i think cause it has a pinkish color(most of the rats died-i.v. s.c.).so to improve this way i'll made a defat w/ hexane first, extract w/ ethanol or meoh and in final step use hexane, note that little solvent is required on my modifications and it'll take 1-2 days to finish
K-boclo