You may want to read this:

Protein kinase C inhibition by plant flavonoids

Biochemical Pharmacology, Volume 38, Pages 1617-1624

Patrice C. Ferriola, Vivian Cody, Elliott Middleton (1989)

Good luck...

Crystal growth depends on purity of your isolated fraction. Try crystallization with~ 1 g of the pure fraction. Acetone can be the best precipitant. Try various temperatures. Store the stock fraction always in a refrigerator and in clear glass storage bottles.  Read crystal growth techniques in WWW.IUCR.ORG. Wish u all the best! 

Dinesh – you may want to confer with Prof Vivian Cody (biochemist/crystallographer/structural biologist), a pioneer in this area, with

The Hauptman- Woodward Medical Research Institute, Buffalo NY, named after the Nobel Laureate, Hrebert A Hauptman, mathematician and crystallographer…

http://www.hwi.buffalo.edu/faculty_research/Cody/cody.html

http://www.hwi.buffalo.edu/about_hwi/nobel_laureate.html 

All the best!