Quantitative Testing of BAC's Effect on Bacterial Growth

RetCurious

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A test with interesting results, aimed at addressing several questions people often raise about BAC.

What is the distinction between bacteriostatic and bactericidal?

Does the 0.9% benzyl alcohol concentration matter much?

What are the consequences when the concentration falls below that level?

At what point, if any, does a lower limit become a concern?

How fast does bacteriostatic water take effect?

Does benzyl alcohol genuinely perform better at room temperature?

How does Genetek bacteriostatic water stack up against Hospira?

Shared with permission, courtesy of jonny_feather.
 
Great! I find it quite unexpected that BAC performs more effectively at room temperature compared to when it is refrigerated. Even so, I'll keep refrigerating my BAC water, since doing so slows down the breakdown of the alcohol itself.

Assuming you have confidence in your BAC, is filtering actually necessary? That said, it probably removes things beyond bacteria as well.
 
RetCurious said:

A test with interesting results, aimed at addressing several questions people often raise about BAC.

What is the distinction between bacteriostatic and bactericidal?

Does the 0.9% benzyl alcohol concentration matter much?

What are the consequences when the concentration falls below that level?

At what point, if any, does a lower limit become a concern?

How fast does bacteriostatic water take effect?

Does benzyl alcohol genuinely perform better at room temperature?

How does Genetek bacteriostatic water stack up against Hospira?

Shared with permission, courtesy of jonny_feather.
Wow!!

That is one incredibly detailed report, and it runs against what a lot of the usual theories would predict in several respects.

Thanks for sharing it, and credit to jonny_feather for carrying out such thorough testing!
 
So it kills far more effectively than the standard 0.9% version. Interesting results, to put it mildly, and it's good to see Genetek tested and confirmed to be just as effective — given its current price, that's quite a deal.
 
Skidude said:

RetCurious said:

A test with interesting results, aimed at addressing several questions people often raise about BAC.

What is the distinction between bacteriostatic and bactericidal?

Does the 0.9% benzyl alcohol concentration matter much?

What are the consequences when the concentration falls below that level?

At what point, if any, does a lower limit become a concern?

How fast does bacteriostatic water take effect?

Does benzyl alcohol genuinely perform better at room temperature?

How does Genetek bacteriostatic water stack up against Hospira?

Shared with permission, courtesy of jonny_feather.
Wow!!

That is one incredibly detailed report, and it runs against what a lot of the usual theories would predict in several respects.

Thanks for sharing it, and credit to jonny_feather for carrying out such thorough testing!
I think jonny_feather may have set up a new account on here, but is unable to post replies? Perhaps @ZippityDooDah could lend a hand with that?
 
RetCurious said:

Skidude said:

RetCurious said:

A test with interesting results, aimed at addressing several questions people often raise about BAC.

What is the distinction between bacteriostatic and bactericidal?

Does the 0.9% benzyl alcohol concentration matter much?

What are the consequences when the concentration falls below that level?

At what point, if any, does a lower limit become a concern?

How fast does bacteriostatic water take effect?

Does benzyl alcohol genuinely perform better at room temperature?

How does Genetek bacteriostatic water stack up against Hospira?

Shared with permission, courtesy of jonny_feather.
Wow!!

That is one incredibly detailed report, and it runs against what a lot of the usual theories would predict in several respects.

Thanks for sharing it, and credit to jonny_feather for carrying out such thorough testing!
I think jonny_feather may have set up a new account on here, but is unable to post replies? Perhaps @ZippityDooDah could lend a hand with that?
Is this guy active over on Peppy R? I'm fairly sure I came across this not long ago. It's one more reason I typically reconstitute a week ahead of when I actually need the product. That advice came from a well known member here.
 
BNLFL said:

RetCurious said:

Skidude said:

RetCurious said:

A test with interesting results, aimed at addressing several questions people often raise about BAC.

What is the distinction between bacteriostatic and bactericidal?

Does the 0.9% benzyl alcohol concentration matter much?

What are the consequences when the concentration falls below that level?

At what point, if any, does a lower limit become a concern?

How fast does bacteriostatic water take effect?

Does benzyl alcohol genuinely perform better at room temperature?

How does Genetek bacteriostatic water stack up against Hospira?

Shared with permission, courtesy of jonny_feather.
Wow!!

That is one incredibly detailed report, and it runs against what a lot of the usual theories would predict in several respects.

Thanks for sharing it, and credit to jonny_feather for carrying out such thorough testing!
I think jonny_feather may have set up a new account on here, but is unable to post replies? Perhaps @ZippityDooDah could lend a hand with that?
Is this guy active over on Peppy R? I'm fairly sure I came across this not long ago. It's one more reason I typically reconstitute a week ahead of when I actually need the product. That advice came from a well known member here.
Yep, that is him — @jonnyp . Bringing 20 years of pharmaceutical industry experience, he draws on it to help sharpen our grasp of the challenges we face.
 
Bird_of_Hermes said:

Great! I find it quite unexpected that BAC performs more effectively at room temperature compared to when it is refrigerated. Even so, I'll keep refrigerating my BAC water, since doing so slows down the breakdown of the alcohol itself.

Assuming you have confidence in your BAC, is filtering actually necessary? That said, it probably removes things beyond bacteria as well.

The explanation for why it works better at room temperature is here

Reply within the thread 'Where to store this Bac Water after use?' /community-link/thread/14030/
 
Really fascinating stuff! My usual habit is to reconstitute and then pin right away, but after going through this I'll certainly be rethinking that routine.

It's also good to know Genetek is performing well, since I have some headed my way!
 
NagChamp said:

Really fascinating stuff! My usual habit is to reconstitute and then pin right away, but after going through this I'll certainly be rethinking that routine.

It's also good to know Genetek is performing well, since I have some headed my way!
When a filter is part of your process, there is likely no need to wait.
 
RetCurious said:

A test with interesting results, aimed at addressing several questions people often raise about BAC.

What is the distinction between bacteriostatic and bactericidal?

Does the 0.9% benzyl alcohol concentration matter much?

What are the consequences when the concentration falls below that level?

At what point, if any, does a lower limit become a concern?

How fast does bacteriostatic water take effect?

Does benzyl alcohol genuinely perform better at room temperature?

How does Genetek bacteriostatic water stack up against Hospira?

Shared with permission, courtesy of jonny_feather.
Appreciate you posting this in our community!
 
pretty fascinating, and it lines up with other research on this topic.

That said, it comes across like a student exam paper. Doesn't really matter though. The photo evidence backs up the result.

and somebody actually put in the real work. glad to see it

you should also look into the studies and tests covering peptide breakdown at room temperature.

before you go storing your peptides for the bactiacide effects. (spoiler: Triz remains stable for up to 4 weeks)
 
RetCurious said:

Any recognition for this belongs entirely to @jonnyp
Here's what's been running through my mind regarding this:

When it comes to killing bacteria, BAC does the job well. However, the number and strain of organisms involved will determine how many Endos end up in the solution.

When only a tiny quantity of bacteria gets introduced, the fast kill rate appears to stop a large buildup of bacteria and Endos from taking hold.

On the other hand- should bacteria already be in there because the lyophilized powder wasn't sterile, that's where trouble could arise.

This appears to leave us with Static protection against what gets introduced, rather than any protection tied to sterility.

I'd really appreciate hearing what others think about this....
 
Skidude said:

RetCurious said:

Any recognition for this belongs entirely to @jonnyp
Here's what's been running through my mind regarding this:

When it comes to killing bacteria, BAC does the job well. However, the number and strain of organisms involved will determine how many Endos end up in the solution.

When only a tiny quantity of bacteria gets introduced, the fast kill rate appears to stop a large buildup of bacteria and Endos from taking hold.

On the other hand- should bacteria already be in there because the lyophilized powder wasn't sterile, that's where trouble could arise.

This appears to leave us with Static protection against what gets introduced, rather than any protection tied to sterility.

I'd really appreciate hearing what others think about this....

In my opinion, this is why testing for endotoxins carries more weight than sterility testing.

Sterility can be achieved through filtration, and that also stops new endotoxins from forming down the road, but once endotoxins are already present in the solution, there's essentially no way to remove them.
 
RetCurious said:

Skidude said:

RetCurious said:

Any recognition for this belongs entirely to @jonnyp
Here's what's been running through my mind regarding this:

When it comes to killing bacteria, BAC does the job well. However, the number and strain of organisms involved will determine how many Endos end up in the solution.

When only a tiny quantity of bacteria gets introduced, the fast kill rate appears to stop a large buildup of bacteria and Endos from taking hold.

On the other hand- should bacteria already be in there because the lyophilized powder wasn't sterile, that's where trouble could arise.

This appears to leave us with Static protection against what gets introduced, rather than any protection tied to sterility.

I'd really appreciate hearing what others think about this....

In my opinion, this is why testing for endotoxins carries more weight than sterility testing.

Sterility can be achieved through filtration, and that also stops new endotoxins from forming down the road, but once endotoxins are already present in the solution, there's essentially no way to remove them.
Sterility matters too, in my view. If bacteria are present, the BAC water killing them could still leave endotoxins behind.
 
If you filter right away once reconstitution is done, there wouldn't be much time for dead bacteria remnants to form, as far as I can tell. Is there something I'm overlooking here?
 
One line in the preparation description caught my attention:

A final filtration through 0.2 micron PES was carried out to give sterile benzyl alcohol solutions that were stored in sterile bottles prior to use.

This wording appears to assume filters work with 100% effectiveness. A worthwhile experiment would involve diluting the inoculation solution into sterile water to create a standardized non-sterile solution, then filtering it and testing on agar.

Beyond that, the procedure demonstrates that when judged by a bacteriostatic measurement at least, basic homemade solutions perform at least as well as Hospira. It's one more sign of just how absurd Hospira's price fixing has become. They simply don't possess an economic moat of that kind.
 
RetCurious said:

If you filter right away once reconstitution is done, there wouldn't be much time for dead bacteria remnants to form, as far as I can tell. Is there something I'm overlooking here?
That's a fair point.
 
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