Proteins in the stool could be arising from the microbial population present in the stool, the diet, or the host tissues. Are you interested in total proteins present in the stool or a specific fraction? What is the purpose of the study?

I want to see if a human protein is present in the stool, so I'm interested in total proteins.

In this case, I suggest suspending a known weight of the stool in 5-10 volumes of 0.05M Potassium phosphate buffer pH 6.8 and vortex well. Let stand in cold for few minutes to precipitate the heavy particles. Remove the top fraction and centrifuge at low speed ~2000g for 5-10 min to remove solids and bacterial cell. Use the supernatent for your ELISA assay or for further concentration and purification by ion-exchange chromatography, gel filteration, ion chromatography or preparative electrophoresis. Good Luck  

Valeria Caneparo i'm currently seeking a method for human protein extraction from stool. Did you try the buffer suggested by Hosni M Hassan ?

kind regards

Victor Cuevas Espinoza, in our lab we used the following protocol for protein extraction for mouse stool:

"Freshly collected or frozen fecal samples were reconstituted in PBS containing 0.1% Tween 20 (100 mg/ml) and vortexed for 20 min to get a homogenous fecal suspension. These samples were then centrifuged for 10 min at 12,000 rpm and 4°C. Clear supernatants were collected and stored at −20°C until analysis. Lcn-2 levels were estimated in the supernatants..."

This protocol was found in the following article: Article Fecal Lipocalin 2, a Sensitive and Broadly Dynamic Non-Invas...

I now want to perform ELISA on supernatant from human feces. Victor Cuevas Espinoza ,which method/buffer did you end up with?