Hi everyone,
There are many protocols in many papers but I wonder where we can find most reliable and easy protocols? I am looking for measuring Total Phenolic content, Total Flavonoid Content and Antioxidant properties of '' ETHANOLIC'' extract of leaves and flowers from a plant. Many thanks in advance.
The protocol is simple. Main steps are: 1. extraction 2. isolation 3. separation 4. identification. You can also read my papers.
Article Phytochemical Screening and Free-Radical Scavenging Activity...
Dear Pery Perv,
The origin for determining total phenols is Singleton and Rossi (1965) that paper was Cited by 11263 until this moment. I have followed this method with little modification in my recent publication, I am sure that will help you.
Best regards
Aly
Article Analysis of phenolic acids and anthocyanins of pasta-like pr...
As suggested by experts, please refer the following ref.
v Singleton, V. L., and Joseph A. Rossi (1965) Colorimetry of total phenolics with phosphomolybdic-phosphotungstic acid reagents. American journal of Enology and Viticulture 16.3, 144-158.
Best wishes,
A. Muthusamy
See this link also
Article Comparative Studies on the Phytochemical Properties of Five ...
Colorimetric Method using Folin Ciocalteu Reagent. ISO method,
Ref. BS ISO 14502-1: 2005 (2005).
I agree with Phillip Morris. However, whatever you will use as method, values won't be really comparable to others. Further, TPC is a method that can be only used as a rough estimation what is in a sample.I am wondering that still so many researchers do this parameter, as it truly does not say anything detailed....
To be sure that you measure exactly phenolic compounds you need to do HPLC.
Dear Pery, thank you. Yes, for a primary indication, this is OK. We also do it like that...Of course there are quite many, sometimes very confusing protocols, but I believe that in most cases, one cannot do something wrong...
Dear Scientists,
Be aware with the facilities available in developing countries, we can not deny that Singleton and Rossi (1965) give an overview idea about the total phenols and had some interference with other compounds, not only this method but also most of the colorimetric methods such as determination of TBARS in foods. The bad science is to make scientists desperate to to do science specifically in developing counties, if we need to do good science give the alternative that can be done in poor countries. This is the good science ( small is beautiful even for comments)
Good luck
Aly R Abdel-Moemin