Try the protocole described in the following reference

Jurgen, C.; Bernhanrd, V., Sabine, Iris, K. J. Nat. Prod. 2001, 64, 299

Do you have an crude ethanolic extract???

If you have one, you can try separation with petroleum ether (expel steroids). After that, the residue, you can wash with 30ml EtOH:H2O (1:7), heat and filter. In this way, get an extract semi-purified for subsequents separations.

A good article to consult: Food Chemistry, Volume76, Issue4, April 2002, Pages 519-525 "Comparison of methods for the hydrolysis of flavonoids and phenolic acids from onion and spinach for HPLC analysis." See attachment of the abstract appended.

It may be applied by using H2SO4 at low concentration. But you still should consider the possibly polymerization for a side product.

I really extract polyphenols from pomegranate peel by using either ethanol or acetone or even water as solvents.

We work in radiopharmaceuticals development and during synthesis we use acid and basic hydrolysis. I don´t have experience in plants......

Use 1ml 1N HCl in 60% methanol in your plant extract and reflux it for 6hr. You will get your free phenolic acids and analyzed on HPLC using C-18 with ACN/H3PO4.

Gud luck:)

Thanks your attention

Methanol - water (e.g. 75% - 25%) should work for the intact phenolic acid glycosides, if you want to hydrolyze them, you can use the abovementioned procotol..(:

Yes . Acid hydrolysis helps to releasae acid aglycones but should be washed with water without loosing the active content. H3PO4 or dil Hcl or Citric acid can be used.

You may see publications from Prof. V.G. Gaikar. His team worked a lot on the extraction of plant ingredients. Method used is a newer one with complete green process.

I just know the hydrolysis of capsaicin glycoside. You can try using extraction with 80%EtOH in aqueous, 3 M HCl as acid hydrolysis, for 3 hour at 95 degree celcius. After that use EtOAc to extract phenolic.

aceton with 1% HCl

Yes! its true.............i have this experienced during my research work which related to isolation of natural products.

The nitric acid can be used?

You shoul try with different HCL concentration, time of hydrolysis, and different temperatures. If you wish transfer all glycone into aglycones use the most rigid conditions.

I nedd protocol for extraction and analysis of organic acids as malic, fumaric, citric,,,,,,,,,,,from juce or fruits especially from moalass ( sugar juce or cirop of beet)

Thank you

I don't recommend using acid hydrolysis, most of the time the acid is too concentrated and can disrupt the A or B ring. Instead use enzymatic hydrolysis to convert the glycosides to aglycones. It is easier and more specific, see attached my publication where I detail the method and if you want also refer to Erlund papers, good luck!

Interesting article Jaime!

thanks Jaime

you are very welcome guys, glad to help. I will try updating my papers on my profile little by little