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Chemistry Forums for Students => Organic Chemistry Forum => Topic started by: CatIon on August 15, 2015, 05:24:27 PM

Title: Theanine extraction from Green Tea
Post by: CatIon on August 15, 2015, 05:24:27 PM
Recently, I have been reading about Theanine isolation from green tea. One of the required materials is a Cation exchange resin (Or an Ion exchange resin). The resin mentioned in the paper I have read is called resin no.732 purchased from Evergreen Chemical co. I had looked on Evergreen's site, but I didn't find any Ion exchange resins for purchase or even any mention of it. So I looked elsewhere and I found a site that had lots of resins for purchase. My question would be, what type of resin should I be looking for to use in the extraction of Theanine from Green tea?
Title: Re: Theanine extraction from Green Tea
Post by: phth on August 15, 2015, 08:36:19 PM
is it the same ion under acidic conditions and basic conditions?
Title: Re: Theanine extraction from Green Tea
Post by: CatIon on August 18, 2015, 04:58:17 PM
If you mean the pH levels then the pH level mentioned was 4.73, which I guess would be optimal.
Title: Re: Theanine extraction from Green Tea
Post by: Babcock_Hall on August 18, 2015, 06:13:39 PM
Cation exchange resins can be strong or weak; therefore, it would help to find out more about this particular resin.  So far, I did not find anything.
Title: Re: Theanine extraction from Green Tea
Post by: phth on August 18, 2015, 06:38:50 PM
I see epichlorohydrin+polypropylene glycol from google http://www.sigmaaldrich.com/catalog/product/aldrich/406732?lang=en&region=US
Title: Re: Theanine extraction from Green Tea
Post by: CatIon on August 25, 2015, 05:26:19 PM
I see epichlorohydrin+polypropylene glycol from google http://www.sigmaaldrich.com/catalog/product/aldrich/406732?lang=en&region=US
So is this the one I should try to use?
Title: Re: Theanine extraction from Green Tea
Post by: phth on August 25, 2015, 08:01:16 PM
It's easier to do the extraction when the cell wall is neutral because the majority of the extraction; pKa COOH ~4.8 so at 3.8 pH there will be 1% left as anion if we use that pH.  That removes a large portion of the mixture.  Look up the values because you wanna use as little acid as possible to avoid decomosition.  So now the mixture is nitrogen bases like amino acids, caffeine, theobromine, oligiopeptides, proteins etc.  Now you can determine which is caffeine or not by UV, but theanine or the others.  So you gotta measure the conductance of the eluent unless the paper you got tells you exactly how long to wait, and if so just follow the procedure exactly and get this resin.  I just googled the term 732 resin and got that as the result, and it will bind cations.