[gmt1986]

Hello,

Sorry if I sound a bit distant but I am trying to extract growth hormones from seaweed on a small scale.

It is done commercially by acid hydrolysis. I was hoping to try this on a small scale using around 5kg of dried seaweed.

I have sulphuric acid and really need a guideline to the process ie:
*How much water to mix with the seaweed
*how much acid to add
*what temperature it should be kept at
*how long should it be exposed to these conditions

Any other info would be grateful.

Thanks
G

[Arkcon]

Well, you should be following a more detailed method, but I'll play along ...

*How much water to mix with the seaweed

Dunno.  Maybe none?  If its pure sulfuric, you'll char most organic material, so that's a bad idea.  If its moderate strength sulfuric, maybe you need no added water.  Often, when we try to extract something from plant material, we remove the dominant impurity -- water -- first.  That means drying.

*how much acid to add

Hmmm.  Enough?  As in enough to cover, or to saturate the material, or react with the possible amount of products and impurities.

*what temperature it should be kept at

Ambient?  Slightly elevated for more extraction efficiency?  Probably not boiling, unless the product is very robust.  Possibly cold if its very sensitive?

*how long should it be exposed to these conditions

'til its done.  Sorry, got tired of asking questions, and felt like being definitive.  Extract for x period of time, then extract for more, and see if its still extracting.  Then use that duration the next time.  That's called SCIENCE.

Any other info would be grateful.

Yes it would.  What are you trying to extract?  From what?  Where did you hear of the procedure?  What is the benefit acid provides?

[WW]

As with any natural product, sample preparation is key.  there are some cases where wet material is used, but my inclination is generally to freeze-dry and homogenize the plant tissue first.

As the other poster commented, yes we can't answer these questions specifically without more information.  Are you trying to hydrolyze the cellulose to measure the concentration via sugar analyses?  I would search a database like science direct if you have access and find the actual method for doing so.  What use is it to do this anyway if you don't have a method to reference?  you certainly can't reference this forum.  don't reinvent the wheel here, find the method!