The suggestions given by Dr. Gollapudi Rao should be tried out as I have tried it and got the required results.

Go for LC if possible. Crude extract will kill your GC column.

Dear Dr. Basudeba, 

I agree with the previous suggestions. I've worked with roots using this method

http://onlinelibrary.wiley.com/doi/10.1046/j.1365-313x.2000.00774.x/full

with extraordinary results. As a recommendation I would suggest the use of a column prepared for high temperatures, like 

http://www.agilent.com/en-us/products/gas-chromatography/gc-columns/capillary/vf-5ht

and the use of MSTFA as derivatization reagent.

Cheers, 

Carlos