Dear Gaurav Kumar

You should follow OECD guidelines OECD-423 for assessing the acute oral toxicity of the plant extracts. Following are the references that you must refer before undertaking the acute oral toxicity studies:

OECD 423 (2001) OECD Guideline For Testing of Chemicals Acute Oral Toxicity – Acute Toxic Class Method Adopted: 17th December 2001.

Roll R, Ho¨fer-Bosse T, Kayser D (1986) New perspectives in acute toxicity testing of chemicals. Toxicol Lett Suppl 31:86.

I hope this will end your search. You should follow the procedure given in the guidelines and you will get the exact result. I am attaching the .pdf of OECD 423 for your perusal.

Gud Luck

Regards

You may go up to 4gm/kg body wt (up to 80 mg/animal/day) for mice weighing 25gm. I have used it without any toxic effect in mice, plant of my interest was Mentha piperita Linn. aqueous extract.

Dear Gaurav Kumar,

For ethical reasons, I would like to see a harmonisation between the chemical and pharmaceutical regulations. According to the ICH guideline M3, LD50 studies are no longer required, and the maximum dose is 1 mg/kg bw in general. See attached guideline.

Regards,

Kerstin

Attachment:

Dear Kumar,

As Dr Nahata suggests, OECD guidelines are a good start. A 5gm/kg limit test is provided for in the guideline, but because of welfare concerns, its use is limited to situations where the results obtained will likely have direct relevance in the protection of human, animal or environmental health.

Regards and all the best...

Kuria.

Thank you all for the valuable suggestions and literature

For Plant extract you can use 5000 mg/kg and follow the OECD 423

Creo que los extractos deben ser analizados bien antes de usarlos en pruebas que requieran exactitud de concentración efecto, ya que suelen variar los resultados y requerir planear varios estudios para utilizar un promedio.

You can use 1/10 LD50 as maximum dose and lower to prepare serial of doses.

OECD 423 is good for acute oral toxicity.

Better to look at the EC50; then you may take a look at the maximum dose needed, and follow the OECD guideline and follow the starting dose chart.