Hi, my topic is phytochemical and antioxidant properties of selected species of lamiaceae" i have screened samples by dpph method, now i want to do quantitative analysis of sample which method should i use for analysis please suggest.
Go for total phenolic content (TPC) and total flavonoid content estimation...
DPPH is not a enough to make conclusion on the antioxidant activity. At least two assays are recommended. And for you understand and to identify the compounds you can go for HPLC
Regards
You can go with HPLC, HPTLC or GC-MS the benefit with GC-MS is that you have libraries there which will be very helpful in screening the metabolites present in Sample.
For preliminary phytochemicals screening prefer laboratory guide for the analysis of Ayurveda and Siddha formulations. CCRAS publication
For quantitative analysis prefer method of book " Methods of Biochemical Analysis" Written by S.K. Thimmaiah
Different types of phytochemicals such as alkaloids, tannin, saponins, flavonoids, carbohydrates, protein, resin, steroids etc.
Two methods are available: gravimetric and spectrophotometric
It is depend you which type of method you preferred but spectrophotometric method is widely used due to more accurate and rapidly.
Alkaloids by dragendorff reagents method by using spectrophotometric.
Determination of alkaloids by Harborn (1972) method
Soluble Protein by Lowery's method
Total carbohydrate by anthrone method
Tannin estimation by folin-denis method
Flavonoids estimation by Bohm- Kocipay Abhayzan method
Saponins estimation by obadami ochuko (2001) method
Hello Bhagyashali Karle
What plant part you are going to use for your study As lamiaceae plants mostly contains aromatic compounds in it. It might contain some volatile component as a phytoconstituents. for antioxidant assay you may go for DPPH, Fenton and H2O2 assays. You may also go for Total phenol contain study. You go for HPTLC, HPLC and GC. firther you may go for Mass study.
You can do HPLC and GCMS estimation which will help you for quantitative analysis of sample. But one more thing I want to include you can use superoxide scavenging assay and nitric oxide radical scavenging assay for determination of antioxidant activity.
Generally, but not only, phenolic compounds are responsible for antioxidant activity and HPLC can be helpful, but it will depends which kind of extract you have (crude extract with polar solvent or fractions). You can select some standard compounds, such as quercetin, gallic acid, etc, and quantify them in you extract (or fraction) by HPLC. Only DPPH for antioxidant activity is not sufficient, as Alkasim and Pawan pointed out, you need to do more tests.
The most good HPLC method If you have a standard, the most classical method is extraction, fractionation and chromatography, there is a chance to find a new natural compound
Hi Bhagyashali Karle,
i just finish my research using plant "laminacea", for phythocemical constituen i used harborne method, for alkaloid using dragendorf, meyer and wegner solutaan, for flavonoid using LB and using ABTS and FRAP assay for antioxidant, for quantitative i used spektro UV-VIs and GCMS, FTIR instrumen
Dear , it depend on your target.
Hplc, or uhplc can be the standard method to catch some peaks of your interest for routine.
If you want to develop the finger print of your product , this is just pre-hystory... so depend what is your target.
for cheap detection of "total polyphenols" the uv reading with folin or iron salts can give a quick answer.
hape has been helpfull
HPLC/MS- it is capable of analysing a much wider range of components.
Since you are using DPPH as an antioxidant screen, the most predominant antioxidants in the mint family will be phenolics. A generally accepted method for quantification of phenolics is the Folin-Ciocalteu method. Should you need more detailed quantification of phytochemicals, then HPLC-UV or LC-MS for quantification and identification is recommended.
A number of factor comes to play. It may not be useful to single out one method and say that's all you need. The plant you are working on can be made up of hundreds of chemical constituents. So to start with, I will advice you employ simple quantitative techniques such as the conventional chromatography and spectrophotometric techniques. Results from here will give you an idea on what sophisticated analytic technique you should employ. But recently, the most readily available sophisticated techniques that will give you a better result is the hybrid analytical techniques such as GC-MS, LC-MS, GC-IR, LC-NMR etc.
Dear Bhagyashali Karle, Kindly refer few standard books for your goal.
I will prefer "Herbal Drug Technology" written by Pulok Mukherjee and "Phytochemical Techniques" by Siddiqui.
For literature survey you can find one of my review article published on Lamiaceae family in attachment section.
- Badges
- Science topic
- Similar topics
- Chemistry
- Pharmacology
- Pharmaceuticals
- Drugs