what are the factors needed for the growth of bacteria?
Since this is not my area of expertise, I searched Google under the key words "bacteria 'growth factors'" to get these possible sources:
http://textbookofbacteriology.net/nutgro.html
http://student.ccbcmd.edu/courses/bio141/lecguide/unit6/metabolism/growth/factors.html
http://www.aber.ac.uk/biology/MicroSite/young2.html
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=374571
http://72.14.253.104/search?q=cache:kZZ9Iv2krmcJ:science.nhmccd.edu/biol/wellmeyer/lecture/bgrowth.doc+bacteria+%22growth+factors%22&hl=en&ct=clnk&cd=16&gl=us&client=safari
In the future, you can find the information you desire more quickly, if you use appropriate key words to do your own search.
I hope this helps. Thanks for asking.