Dear Kishor,

You can use the extraction procedure indicated in the following link with the aid of TRIzol and RNA purification kit.

http://www.ncbi.nlm.nih.gov/pubmed/20329549

Hoping this will be helpful,

Rafik

https://www.zymoresearch.com/dna/microbial-environmental-dna-isolation-1/soil-fecal-plant-dna/zr-fecal-dna-miniprep 

Very useful for solving your task.  I have long time experience with this kit, working fine. 

Dear Karen,

Thanks for your suggestion. I am afraid, this is the kit to extract DNA not RNA. I am looking a kit for RNA extraction. 

Dear Rafik,

Thanks for providing the link for the paper. However, I couldn't get the English version of this paper. This paper is in Chinese. 

You do not use any kit for this. See the references given by Rafik and Karen and just follow the instructions there.

We have good and repetitive results by using PowerMicrobiome RNA Isolation Kit (MoBio). It  runs properly coping with soil, sludge and pellets from culturing biomass when previously sored on RNA later or LifeGuard.