- Joined
- Oct 30, 2003
- Messages
- 57
I'll respond with a more complete exegesis on this topic shortly...
...But for now, I'm going to leave everyone reading this with a few thoughts.
If you have any questions about just how spectacularly well fungi can spread, I can only direct people to do a few Internet searches; look specifically for (say) Cordyceps and anything in the Order 'Hypocreales' -- or just search using the terms:
entomopathogenic fungal culture
..And that should get you to ARSEF's stuff quickly enough, not to mention papers from the Society for Invertebrate Pathology (http://www.sipweb.org). Any number of their members in the division devoted to Fungal Pathogens of Invertebrates have written plenty of papers on the subject which should answer the questions posed here.
If for whatever reason you can't find what you need to clear up any & all misconceptions (some of the stuff is member-restricted, I think), then I'll be happy to provide the appropriate citations, as I am a member, and have the papers/newsletters/etcetera.
To quote from an elementary laboratory worker's handbook, "THERE IS NO SUCH THING AS 'MOSTLY' STERILE", and on this, Rasputin is correct: the temps and pressures cited above are adequate to render medical and/or laboratory equipment sterile.
[N.B.: The below is not in reference, necessarily, to various Entomopathogeni fungi, but fungal spores in *general*, as there are a variety of species which do this -- more than I know of offhand.]
When it comes to various substrates, however, there is a reason why (speaking from a mycological standpoint) various media and substrates are 'pre-soaked' for a day prior to autoclaving, as -- I kid you not -- mere autoclaving is inadequate to destroy certain (many) spores, and one has to force them to 'open up' (as it were) because only then are they vulnerable, so while being in what they 'view' as environmentally hostile conditions, including lack of hydration, temperature extremes, etcetera, they lie dormant, virtually impervious, in a spore state. Once soaked in water and left at circa 72 degrees F for 24 hours or so, they 'come out of their shell', and as it takes more energy to re-form themselves into their previously near-impervious form (and they need longer than a day at that temperature to gather the necessary nutrients to do so), they are then pervious, and autoclaving is adequate to dispatch them.
There is a reason why Chloramphenicol is used in PDA slants & petri dishes; while fungicidal (for a very few fungi) and bacteriostatic at the very least, it's what I have & use, and the industry standard (AFAIK) for culturing fungi, while helping keep bacterial candidates out (including when one is doing a 'field' sampling/culture, as successfully culturing XYZ in a petri dish of PDA w/Chloramphenicol is generally indicative of a Fungus, not a Bacteria, Gram +/-.
Rendering surgical steel sterile is, in contrast, easily done: rendering virtually any porous substrate sterile is relatively difficult, in contrast, as the temperatures needed to destroy certain spores/endospore-forming microbial lifeforms is, all things considered, generally high enough to carbonize the material in question....Which defeats the purpose, I'd wager.
The amount of Gamma radiation which is used for (say) a #24 scalpel blade would be inadequate for coco coir, believe it or not (I am sure there will be doubters, and for those uninterested in doing research themselves, I'll be posting the info and appropriate citations & links later on, including links & whatever PDF's I can publish on the website w/o violating copyright.
More later,
~JMB
~JMB
...But for now, I'm going to leave everyone reading this with a few thoughts.
If you have any questions about just how spectacularly well fungi can spread, I can only direct people to do a few Internet searches; look specifically for (say) Cordyceps and anything in the Order 'Hypocreales' -- or just search using the terms:
entomopathogenic fungal culture
..And that should get you to ARSEF's stuff quickly enough, not to mention papers from the Society for Invertebrate Pathology (http://www.sipweb.org). Any number of their members in the division devoted to Fungal Pathogens of Invertebrates have written plenty of papers on the subject which should answer the questions posed here.
If for whatever reason you can't find what you need to clear up any & all misconceptions (some of the stuff is member-restricted, I think), then I'll be happy to provide the appropriate citations, as I am a member, and have the papers/newsletters/etcetera.
To quote from an elementary laboratory worker's handbook, "THERE IS NO SUCH THING AS 'MOSTLY' STERILE", and on this, Rasputin is correct: the temps and pressures cited above are adequate to render medical and/or laboratory equipment sterile.
[N.B.: The below is not in reference, necessarily, to various Entomopathogeni fungi, but fungal spores in *general*, as there are a variety of species which do this -- more than I know of offhand.]
When it comes to various substrates, however, there is a reason why (speaking from a mycological standpoint) various media and substrates are 'pre-soaked' for a day prior to autoclaving, as -- I kid you not -- mere autoclaving is inadequate to destroy certain (many) spores, and one has to force them to 'open up' (as it were) because only then are they vulnerable, so while being in what they 'view' as environmentally hostile conditions, including lack of hydration, temperature extremes, etcetera, they lie dormant, virtually impervious, in a spore state. Once soaked in water and left at circa 72 degrees F for 24 hours or so, they 'come out of their shell', and as it takes more energy to re-form themselves into their previously near-impervious form (and they need longer than a day at that temperature to gather the necessary nutrients to do so), they are then pervious, and autoclaving is adequate to dispatch them.
There is a reason why Chloramphenicol is used in PDA slants & petri dishes; while fungicidal (for a very few fungi) and bacteriostatic at the very least, it's what I have & use, and the industry standard (AFAIK) for culturing fungi, while helping keep bacterial candidates out (including when one is doing a 'field' sampling/culture, as successfully culturing XYZ in a petri dish of PDA w/Chloramphenicol is generally indicative of a Fungus, not a Bacteria, Gram +/-.
Rendering surgical steel sterile is, in contrast, easily done: rendering virtually any porous substrate sterile is relatively difficult, in contrast, as the temperatures needed to destroy certain spores/endospore-forming microbial lifeforms is, all things considered, generally high enough to carbonize the material in question....Which defeats the purpose, I'd wager.
The amount of Gamma radiation which is used for (say) a #24 scalpel blade would be inadequate for coco coir, believe it or not (I am sure there will be doubters, and for those uninterested in doing research themselves, I'll be posting the info and appropriate citations & links later on, including links & whatever PDF's I can publish on the website w/o violating copyright.
More later,
~JMB
~JMB