Dear Sony

Are you use alcohol for the extraction of chemical constituents from the plant parts?

If you are using the organic solvents, it is easily evaporate the organic solvents (any) under the room temperature on the large surface area plate (simply petridishes) with 1-2 days. No pathogens can grow on the extracts in this process, but pathogens can grow on the extract prepared from water.

Dear Sony,

A rotary evaporator has shear forces acting as the flask spins and the liquid tumbles, this can denature proteins and also create foams.  These may not be an issue for your extract, but are best avoided.  The advantage is the large surface area and good heating from the bath.  Other techniques that are commonly used are freeze drying or centrifugal evaporation, although the latter is generally only use where you have more than one sample, although if you have one large sample ... it works too.

The challenge for any drying technique is to preserve a large surface area.  Most of the alcohol will evaporate easily enough, but the water that comes with the plant material (and there will be some) generally is very difficult to remove, especially if the extract thickens and stars to form a film on the surface.

Kind regards

Rob

I agree with Dr Darrington.

I would also suggest to avoid the evaporation at room temperature. You may need to leave the flask open and also a high surface for evaporation for an efficient procedure. In a first time you may have a good evaporation but when the water content will be high the evaporation will be reduced. In addition below 10 % of ethanol several microorganism may survive (mainly yeasts or fungi) and their methabolism may change the original composition of the extract creating so several artifacts.