Dear Muhammed,

a method for all cases does not exist. We are using both a sequence of solvents from the apolar one (esane) to chloroform, ethanol and water, and pure methanolic extract. The results atre very interesting comparing the mass spectra of all the extracts. Best wishes, Sabino

I think the following paper may help!

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3218439/

By using soxhlet we first extract by pet ether 60-80 and this fraction is rich in fats (Extract A). Then by chloroform or methylene chloride (collected as Extract B). Followed by butanol (Extract C) and finally with methanol (Extract D). You can then use water to extract salt radicals and ions.

You can use the way microwave power at 300 w , temperatures 80 c and the time of 45 minutes and the use of methanol solution of 80%

there is no general method for isolation of all classes of compounds. however it depends on your approach of isolation either you are targeting certain class of compounds or you are doing bioassay guided fractionation or even aiming to study metabolomics.

in the first case the extraction method depends on the chemistry of the target compound,for example; if you aim to isolate alkaloids you can perform acid base extraction, if you aim to isolate hydrocarbons, non oxygenated terpenes or sterols you can carry out saponification of the least polar extract (hexane). for oxygenated terpenes the chloroform extract is suitable. the ethyl acetate extract contains a large variety of compounds, the butanol extract contains polar compounds like saponins.

meanwhile miscellaneous examples can happen

Thanks to all...