Hi Martin, 20% w/v should do it. Have a look at the following link -
quite a good review of methods for direct extraction from soil and
isolated soil bacteria.
http://www.science.uwaterloo.ca/bpo/1/6/a6.htm
Best of luck
Eoin
________________________________
Dr. Eoin Brodie
Dept Industrial Microbiology
University College Dublin
Belfield
Dublin 4
IRELAND
Tel. +353 1 716 1574
Fax. +353 1 716 1183
________________________________
---
