Hi, Aderonke,

You may consider using a rotary evaporator to separate the solvent from the plant crude extract. As long as the crude extract is mixed with the solvent, freezing properties of the extract are still affected.

Please below link. This might help.

https://www.jove.com/science-education/5501/rotary-evaporation-to-remove-solvent

Hope this helps.

Best,

Arizaldo

You could use stove for that, after rotary evaporator using for concentrating.

Dear Aderonke,

Drying will depend on the nature of your extract and, what you what to do with the exract when it is dry. Some drying methonds will affect the properties of elements of your extract as Arizaldo has said. For example, lots of head can boil or oxidise lighter fractions of the extract, but if these are not of interest, you may not be concerned. If you are looking for protein activity post extract drying, then take great care and keep everything cold - this will mean drying under vacuum (low pressure = low boiling point of solvent = cold sample) without mechanical action - so a freeze dryer and not a rotary evaporator (the mechanical action of the rotation can damage proteins). The problem with a freeze dryer is that few commercial systems can freeze dry ethanol so a simply try freezing the sample and using this as a way to separate the ethanol (which doesn't freeze so easily) before moving to the freeze dryer. This is not a 100% type of method, but helps.

Typically - you should use a drying method where you can keep the surface area of the extract as large as possible. Plant extracts are often complex mixtures, with fats, oils, sugars, cell debris and other things which can form a skin and trap solvent into the sample.

Kind regards

Rob

Thank you Rob, but i want to know if the samples will eventually freeze if kept for a longer period in the freezer. because it has been there for over 24hours without freezing (its just very cold and thick).

Kind regards

Aderonke

Perhaps I have answered you through e- mail. The extracts should be devoid of water as much possible. The semisolid extract can be stored in small aliquots in -20 degree centigrade for months. You can dilute it in same diluent for antimicrobial efficacy study, keeping the diluent as another control.

i agree with Arizaldo Castro u can try using rotary evaporator.It will later form a thick substance which can later be placed in a dessicator

Hi

From my experience most of methanol extract would not dry completely. I would suggest that after you have used the rotary evaporator you leave your extract if a fume hood it will take about 2 weeks to dry up but some of the methanol extract do not dry completely because of oils but that also vary from different plants or the plant part you are using.

I hope I have answered your question

Hello Aderonke.

You may try if the rotary evaporator in order to remove the solvent from our the extract. Then put it in an oven to dry. The dried extract may become sticky or turn to a paste. You can then put it in the freezer. You may try this approach with a little amount of the extract to see how it works, because I worked on an aqueous extract and it worked. Take charge.