Dick: I've seeded a filter with mature media and it seemed to help speed things along. It is a matter of how much. 100% mature media would do the trick, I think.
I'm not sure why folks spend money on bottled bacteria to start-up a system. Most reports indicate no quicker result. I have gotten virtually immediate nitrification with a little puddle pond for guppies by using the residues caught in mats/sponges of an active filter and pouring the dirty brown water into the filter material of the new pond... I would not use the sediments settling in the mechanical portion of a filter, but have used the fine reddish-brown sediment to be found in the biological portion of a filter using mat or sponge media.