hi Abid,

there are many ways to test toxicity of plant. you can perform in vitro as well as in vivo.

for in vitro test, these are commonly test in lab: mtt assay, clonogenic, srb, trypan blue exclusion etc. for dpph, you can test in vitro free cells as free radical scavenging activity not toxicity.

in vivo, you can test in lab animal of your choice, mice or any other against different concentrations of plant extracts.

Hello,

You can follow OECD guidelines 423 or 425 to find out toxicity, LD50 and effective dose of plant extracts.

I second Vabeiryureilai, DPPH cannot be used to test the toxicity of a plant or any other sample.

You can check toxicity of plant by simple brine shrimp test

Dr. Jehan Ara

If just  toxicity is in question:  stored grain pests are better than brine shrimp , dr. Abid Ali sahib  you can get them from SARC,PARC near by your department at the university of Karachi campus

In my view, it is very difficult to suggest any method unless the aim of the toxicity study, in question is known. Please clarify which part of the plant is of interest for you, like root, stem, bark, leaves etc. next requirement would be its extract (water, chloroform or/and both), or raw (if raw, in which form like paste). The aforesaid details will help to design the experiment. Toxicity can be studies in insects, fish, mammals etc. Further, if the plant or its any part is found to be cytotoxic, most dependable answer will be obtained by mammalian model. With best wishes.

Alright  Dr Parvin Kumar you have elaborated the subject I agree with you,  but amongst all the animal models unless otherwise specific; usually when you start toxicity screening first of all you use insects as cheaper and easy to handle subject with less ethical constrains

Very right Sir, I fully agree with your point, however, still it is not clear that in which physical form the test material will be subjected for the toxicity test(s).

since dr.abid ali sahib is performing dpph activity determination therefore, his extract  is expected to be polar / aqueous I guess

I hope, our discussion may be of some use for Dr Abid Ali Saheb. Let us look forward for his response.

Through LD50 or LC50  you can checked toxicity of plant extract . I have attached one paper.

use of shrimp in case of aquatic toxicity and rodent also by Abbots formulla