3 replies to this topic

[bikashpurohit]

Thank you Mike

Edited by bikashpurohit, 03 March 2005 - 05:38 AM.

[jadefalcon]

yes, fungal growth is possible, as ampicillin is an antibiotic directed against the bacterial, not the eukaryotic cell wall and will not harm fungi. but in the short incubation periods needed for bacterial growth (overnight, e.g.) fungal growth should be minimal, if the inoculation with fugi is not to high....

the advice I can give you is too keep your ampi-plates not for too long, since then fungal groth can occur, and inoculate your autoclaved medium with fresh bacterial colonies. when in doubt, just transfer the colonies to a fresh plate, incubate overnight and use fresh colonies of that plate to inoculate you liquid culture. this costs you a day max, but if your cultures are contaminated, there are two or more days of work lost....

mike

[peneliti]

I recently planted oyster mushroom (pleurotus ostreatus) mycellia on PDA. I tried to work as sterile as I possibly could, following the aseptic procedure. But, still, a small black spot came out in my petri dish.  Since it's only sit on small space in agar, is it possible that I just cut it out and save the rest of culture? Does that small black spot has already contaminating the rest of mycella? Thanks

[GeorgeWolff]

assume you mean mycelia
If this is from a natural source - you will have bacterial and (other) fungal contaminants and probably mites as well.  In any case, it appears you're not working with a pure culture.  You might try to cut out some agar plugs with apical (end) tips of the growing fungus and reinoculate those separately.