Antibiotic added to wort?

[Proteinguy1995]

Hey guys,

I am a graduate student in biochemistry and do a lot of protein expression/purification using E.Coli, and P.Pastoris (similar strain of yeast to S.Cerevisiae). Generally I use ampicillin in my yeast starters to limit bacterial growth in the initial stages (yeast strain has AMP resistance gene) as the doubling time for P.pastoris is much slower (90 min) than general bacteria (20-30min) and can easily be overwhelmed in the growth media leading to a lower yield of protein.

Anyways, I had some 100mg doxycycline tablets at home that I was using to treat acne, and thought it would be a good idea to add a little bit to the wort. Doxycycline is much more specific to bacteria than it is to fungus as it targets the 30S subunit of the ribosome (ok, enough science).

One of the degredation products of tetracyclines (at low pH, generally <2) is anhydro-4-epitetracycline, which can lead to falconi syndrome (kidney damage). However, in the case of doxycycline, the absence of a hydroxyl group in C-6 prevents the formation of the nephrotoxic compound.

I added about 5mg/L of doxycycline to my wort just when i pitched my yeast. It was a 3 gallon batch, so about 60mg was added to the whole batch(I was taking 100mg/day for months). Its also interesting to note that ancient nubians used to brew tetracycline beer!

Anyways, I am worried for any possible metabolic products that could have been produced to cause adverse effects. However, it was added in such low concentration that about 1-2mg would make it to 1 beer anyways.

What do you guys think? have you ever used antibiotics in your wort to stall bacterial growth? Do large scale breweries use antibiotics?

Sorry for all the nonsense,
Cheers.

 

[TechFanMD]

Your wort should be nearly sterile at the end of the boil, then MIGHT pick something up by the time the yeast is pitched.....but with good sanitation practice with equipment and handling you shouldn't be worried about bacteria in your beer. A quick starting, active fermentation will handle the rest.

My question would be - why? Unless you're brewing in some way that is unable to be sanitary - I can't imagine it ever being necessary.

 

[Comfort_Zone]

I haven't thought about doing this with wort, but I have toyed with the idea of using antibiotics in starters when I have super low viability.

 

[JimRausch]

As someone in the medical field, I would be more worried that you are creating an environment for selection of resistant bacteria. And we all know about the problems that has created. I also think the same as TechFanMD above- with normal techniques there should not be a bacterial overgrowth. So, with no benefit, and the potential however small, for causing problems, then why?

 

[JimRausch]

I haven't thought about doing this with my work, but I have toyed with the idea of using antibiotics in starters when I have super low viability.

I did use chlorine dioxide once when growing yeast from the dregs of a bottle. I saw bacteria under the microscope and found a technique for stunting/killing the bacteria without killing the yeast.

 

[Comfort_Zone]

I did use chlorine dioxide once when growing yeast from the dregs of a bottle. I saw bacteria under the microscope and found a technique for stunting/killing the bacteria without killing the yeast.

This is what I ended up doing in the past. Like I said, I toyed with the idea but never actually did it. Didn't see the point in a full batch of beer though. If infection is that much of an issue I'd look at procedures first.

 

[mongoose33]

I haven't thought about doing this with my work, but I have toyed with the idea of using antibiotics in starters when I have super low viability.

If you boil the starter DME before adding the yeast, from where would infection come? I know there's always a chance/likelihood of bacteria settling into the starter as it rides along on dust, but the amount has to be tiny.

How low of viability would your yeast be, and why would you be using that instead of fresh yeast?

 

[Silver_Is_Money]

Doesn't doxycycline break down over time and become a toxic substance. I'm not sure I would want to drink a doxycycline dosed batch of beer 6 months down the road.

 

[Vale71]

Do large scale breweries use antibiotics?

I'm pretty sure that's highly illegal in any country where beer is brewed.

 

[Proteinguy1995]

@TechFanMD - I already am aware that the batch is likely sterile enough from boiling + high acid content from the hops. My brew methods are a little unsanitary at the moment due to lack of equipment. I racked the primary over to secondary the other day and let the batch be exposed to air for a little longer than i would've liked. However at this point the alcohol content of the beer would also be contributing to the anti-microbial effect.

@Comfort_Zone - I was using one of the dry yeast packs (Safeale US-05), so viability is lower than having your own starter for sure. I'm just interested in knowing if any large scale breweries use or have used anti-biotics at some point in the process (Im sure they use for making starters)

@JimRausch - I understand the concern, I have thought about this too. However, only a small concentration of doxycycline was used in the batch (lower than a standard daily human dose), and there is not long enough exposure time for selection to occur for a tetracycline. Tetracycline resistant originally took about 10 years to see the first case of resistance after the start of clinical use. Current mechanisms of resistance for tetracyclines include resistance genes, where expression is regulated. This takes years evolutionary to occur, not to mention being under the additional stress of high alcohol concentration, and additional anti-microbial compounds in the wort. Also, what concentration of chlorine dioxide did you use? This is also toxic to the yeast itself, reducing viability in the end?

 

[JimRausch]

Also, what concentration of chlorine dioxide did you use?

I'll have to check back home where all my records are. I did it back in 2012, so have some digging to do. I used the chlorine dioxide prep that is used to purify backpacker's water. Aquapure brand maybe? I'll also see if I can find the reference that prompted me to try it in the 1st place.

 

[Proteinguy1995]

@Silver_Is_Money - Trying to find out what are its possible metabolites/by products. anhydro-4-epitetracycline is not formed however, so no nephrotoxicity from that at least. Only 60mg was used in the whole batch, and the maximum recommended dose is 300-mg daily. I'm not sure if there is too much concern. However, I could be very wrong.

 

[balrog]

I use hops as an antibacterial.

 

[Proteinguy1995]

So far I have found that there is no significant metabolism and no metabolites have been found in man, however nothing on yeast metabolism (for doxycycline). However I assume this is the same, being a less complex organism. Any thoughts?


Agwul, N.K., MacGowan, A. (2006) Pharmacokinetics and pharmacodynamics of the tetracyclines including glycylcyclines. Journal of Antimicrobial Chemotherapy. 58(2), p.256-265

Saivin S, Houin G.(1988) Clinical pharmacokinetics of doxycycline and minocycline. Clin Pharmacokinet. 15, p.355–66.

 

[Comfort_Zone]

If you boil the starter DME before adding the yeast, from where would infection come? I know there's always a chance/likelihood of bacteria settling into the starter as it rides along on dust, but the amount has to be tiny.

How low of viability would your yeast be, and why would you be using that instead of fresh yeast?

This is really something I was looking at when I try and bring back vials that are several years past their date. A local shop gave me tons of free vials that were 3+years past their bbd. Most of the time it isn't an issue though

 

[mongoose33]

This is really something I was looking at when I try and bring back vials that are several years past their date. A local shop gave me tons of free vials that were 3+years past their bbd. Most of the time it isn't an issue though

Ahhh...so you're experimenting just to experiment, trying something just to see if you can do it.

Well, it's not as if I have ever done something like that.....

I have a few packs of way out of date yeast in my refrigerator......

 

[day_trippr]

I don't like any of this. Bad juju written all over it...

 

[MaxStout]

Homebrew treated with antibiotics, you say?

*runs for the door*

 

[Dland]

When the hens we have, we compost the eggs when they are on any systemic medication, this is normal normal to do in a flock a couple times a year.

Dairy cows often have to be treated with antibiotics, and the milk that they give during that time is not legal to sell for human consumption.

It would not be ethical or wise to put that in your beer... Make sure no one knows you were thinking of this, or they will never want to try your beer..{; ...seriously..

 

[bovine_OB]

@Dland hit it on the head. Antibiotics used in production animal medicine must be fully metabolized such that they are below acceptable levels in tissues or edible products (milk). These acceptable levels are determined by dosage the animal receives (my of drug per kg of animal) and route of administration (subcutaneous, transdermal, intramuscular, or intravenous). All of these factor into withrawal time, or time before the drug will be metabolized such that the drug residue meets an acceptable level.

2) adding a low dose of doxycycline, in essence a low concentration (mg of drug per L of wort) does select for resistance. It allows the stronger or more adaptive bacteria to survive while the weak or more susceptible bacteria are affected. This is particularly important with the tetracycline class of antibiotics due to the most common form of resistance is via drug efflux from the bacterium cell.

3) situations like this make my job more difficult - the FDA strictly regulates the antibiotics that I can use to treat illnesses in sick animals. (Antibiotic free animal husbandry is another soapbox of mine). No, one homebrewer experimenting with antibiotics will not likely be the sole cause of antibiotic resistance, but it is the principal - using antibiotics for purposes other than treating infections (read human/animal illnesses) is what leads to resistance, thus those same antibiotics becoming less effective in their medical purpose.

 

[S-Met]

but it is the principal - using antibiotics for purposes other than treating infections

For the sakeof being contrary, @Proteinguy1995 is prophylacticly treating his brew for an infection, a practice very common in medicine. Not saying I would dose anything I ferment with antibiotics, but I'm also not saying that I wouldn't.

I don't make cheese (yet), but people intentionally inoculate cheese with penicillin - an anti-biotic; not that I really needed to point that out. We (I) seek that funky cheese.

And back further into tangential off-topics, homebrewers do all kinds of crazy ****. Adding a multitude of enzymes, acids, salts and bugs to name a few. Many have enough equipment to look like they could be an alchamist.

Due to all us morons out in the world, I would advocate against its use by the average home-brewer to prevent excess contamination and breeding of antibiotic resistance. However, I fully support intelligent and safe research. Besides, if OP finds the next best way to (insert wild claim here), then go for it!

 

[JimRausch]

it is the principal - using antibiotics for purposes other than treating infections (read human/animal illnesses) is what leads to resistance, thus those same antibiotics becoming less effective in their medical purpose.

Thank You Bovine OB for completing my thought. I take it you must be a fellow Vet. Low dose antibiotics in animal feed for the purposes of stimulating increased growth has been something we have been fighting against for years. Sorry Proteinguy1995, I know you mean well, and are just posting an interesting Q, but I've lost animals to AB resistant infections. I pray I never lose a person I know to the same.

 

[RPh_Guy]

Not sure where you're from, but the U.S. has laws against adding dangerous drugs to products.
The FDA protects consumers and doesn't let companies screw around with something so obviously absurd.

So [fortunately] zero beers produced in the U.S. have antibiotics and zero beers imported into the U.S. contain antibiotics.

Transferring a prescription drug to another person is illegal. Possessing a prescription drug without a prescription is illegal. Etc. etc. etc.
All prescriptions must have a legitimate medical purpose to be legal, and being used in a wort starter is obviously not.

 

[Pkrd]

Not sure where you're from, but the U.S. has laws against adding dangerous drugs to products.
The FDA protects consumers and doesn't let companies screw around with something so obviously absurd.

80% of antibiotics in the US are fed to animals. And yeasties animals? I like to think so.

 

[RPh_Guy]

80% of antibiotics in the US are fed to animals. And yeasties animals? I like to think so.

Veterinarians (licensed animal doctors) are treating their patients. The prescriptions and antibiotics still must conform to lots of legislation and distribution control. Then there's the whole other layer of legislation and regulation protecting food products.

Yeast are fungi, not animals (biologically different). There are no such professionals as "yeast doctors" with prescriptive authority.
Researchers may have access to antibiotics, but not for use in any type of industry like brewing or food production.

 

[bovine_OB]

80% of antibiotics in the US are fed to animals. And yeasties animals? I like to think so.

The only anitbiotics that can be fed to animals are now heavily regulated by the FDA, and require a written directive from a licensed veterinarian. Futhermore, only certain antibiotics can be used in animal feed because they were deemed the have a level of resistance the government doesn't want to see progress, and the tetracycline class of antibiotics are one of those the FDA has deemed "medically relevant". It is now illegal to use any antibiotic in animal feed without the consent of a licensed veterinarian, and that antibiotic must comply with a strict set of rules before it can be used.

And no, yeast are not animals.

 

[bovine_OB]

*takes deep breath*
Aaaaand, when researchers study antibiotic resistance by exposing them to resistance selections, the resulting bacteria are destroyed by aterilization or non-antibiotic disinfectants that eradicate the resulting bacterial populations. There is no way for those resistant bacteria to become part of the normal flora of the environment. Simply creating a resistant population in a wort, then ingesting the resistant population puts you at a high risk for developing a bacterial flora within you that are resistant to doxycycline, one of the more effective and medically relevant tetracyxlines. Thus if you were ever to require treatment with a tetracycline for any reason, the bacteria the doctor was attempting to treat would have resistance and the drug would be less effective.

 

[Proteinguy1995]

@bovine_OB - Agreed, and understood from the get go. I am under the assumption that no infectious resistant strains would be present/produced under other conditions in the Wort (low oxygen, less than optimal growing temperature, low pH, high alpha acid content, low sugar post fermentation). Again I only used about 60mg for the whole batch (3 gallon). There are researchers that use 5mg/L doxycycline to prevent bacterial growth in combination with a low doseage B-lactam.

I transferred the batch over to a secondary, it smelled great, and didn't seem to have any problems fermenting.

I am questioning if the batch is safe to drink, or if I should just toss it. I am more so just concerned with any toxic byproducts.

 

[Vale71]

@bovine_OB
I am questioning if the batch is safe to drink, or if I should just toss it. I am more so just concerned with any toxic byproducts.

Do you consider taking antibiotics without a medical reason safe per se?

 

[Dland]

@bovine_OB - I am questioning if the batch is safe to drink, or if I should just toss it. I am more so just concerned with any toxic byproducts.

If it was me, I'd probably drink it if it tasted really good to me. If just so so, or worse, I'd chuck it. If you decide to experiment on yourself, it would be good to have something else around to offer to others, if you have a partner or others at your table.

My pharma knowledge is limited, but I believe doxy type antibiotics do get somewhat toxic if out of date, instead of just getting weaker like some. Not sure if that is relevant, but you asked about byproducts.

 

[day_trippr]

Isn't this how The Blob got started?

 

[Silver_Is_Money]

Whenever taking Doxy it is advised to stay away from direct sunlight, as it sensitizes the skin and can cause sunburns or rashes. Doxy past its due date can cause renal failure.

 

[TwistedGray]

In the reverse, actually I have absolutely no idea if this is in reverse, what about adding probiotics? I find that taking probiotics helps with my guts when I do drink beer. Now I'm usually taking the probiotics early in the morning when I'm hopefully not drinking beer, but I don't know if it would have an impact on when I take it. So I'm wondering if I can just add probiotic to the beer either in the secondary or before bottling?

 

[RPh_Guy]

what about adding probiotics?

Yes, I make and drink sour beer

 

[Proteinguy1995]

@Dland - Thanks for the response, I for sure would not let anyone drink it till I had one myself. I just found some literature stating its 95% stable in acidic medium after 2 weeks, they didn't look far after.

@Silver_Is_Money

Whenever taking Doxy it is advised to stay away from direct sunlight, as it sensitizes the skin and can cause sunburns or rashes. Doxy past its due date can cause renal failure.

I was taking doxycycline, 100mg a day for 2 months. I had no problems with my skin, I also knew about the side effects when i was taking the drug?. There is about 2mg/beer, if all of it is solubilized and stays within the wort, which is unlikely. It's known to chelate divalent/trivalent cations (which wort has plenty of) and precipitate.
It's also not expired, and I doubt most has broken down in solution as of yet.
Can you post your source for the renal failure claim? If this is true, it is probably in circumstances where the patient has impaired kidney function, and has been taking the medication for an extended period of time. Don't forget the standard tablet dosage is 100mg.
https://www.accessdata.fda.gov/drugsatfda_docs/label/2008/050795s005lbl.pdf
https://pdf.hres.ca/dpd_pm/00042598.PDF
Both FDA guidelines and Teva guidelines (the brand of doxycycline i have) say nothing of this.
Updated EUA patient fact sheet by the fda (in case of anthrax breakout mind you):
https://www.fda.gov/downloads/emergencypreparedness/counterterrorism/ucm265824.pdf
* If you have received doxycycline with an expired date on the package, FDA has authorized its use. Testing of the medicine found it is safe to use past the expiration date.
-also says stable in water at room temperature for 14 days.

I appreciate the concern @Silver_Is_Money, but talking to many of my colleagues today (many of whom have PhD's in biochemistry) seem to think there should be nothing wrong, as I initially thought. I haven't spoken with any medical doctors, but I think a pharmacologist, med chemist, or biochemist would be better suited to handle the type of question I posed.

I'll definitely be keeping up with the thread, and give you guys an update after I try one (if the beer is not horrendously off flavored that is)

 

[Proteinguy1995]

In the reverse, actually I have absolutely no idea if this is in reverse, what about adding probiotics? I find that taking probiotics helps with my guts when I do drink beer. Now I'm usually taking the probiotics early in the morning when I'm hopefully not drinking beer, but I don't know if it would have an impact on when I take it. So I'm wondering if I can just add probiotic to the beer either in the secondary or before bottling?

I imagine it would be ok as long as the probiotic can survive the conditions of the beer. It would also be tricky if you are performing natural carbonation with sugar. The probiotic bacteria would likely use some of that sugar, adding off flavours from unwanted metabolic products. I'm sure someone has done it. I also know that some bacteria are encourged in some types of beer to produce the flavour (more sour?).
A quick google search yielded this:
Developing sufficient counts of in beer is a challenging feat as beers contain hop acids that prevent the growth and survival of probiotics.
Try it with a low IBU beer? Or like a barley wine almost? More wheat the better!

 

[RPh_Guy]

I appreciate the concern @Silver_Is_Money, but talking to many of my colleagues today (many of whom have PhD's in biochemistry) seem to think there should be nothing wrong, as I initially thought. I haven't spoken with any medical doctors, but I think a pharmacologist, med chemist, or biochemist would be better suited to handle the type of question I posed.

So, you're driving along some back road and you see a large lake that appears to be frozen. You think to yourself, "wow, that would be fun to drive across." You don't really have a good reason to do it and clearly no one else has driven across the ice.
Then another thought crosses your mind, "maybe it's not safe. I should ask if I can do this."

You call your favorite mechanic, who verifies that yes, your vehicle is functional and can drive across a frozen lake.

Next you call a meteorologist, who tells you that it is currently just below freezing temperature, allowing ice to form.

Finally you call your friend who's a physicist with a PhD. She tells you that ice is a solid and your vehicle is able to drive across a solid surface.

Now let's test your real-world critical thinking skills. Up 'til now, none of these highly qualified professionals related to this task have told you that the lake is unsafe to cross, and you have some pretty reliable facts.
Do you drive across it?


....
What you don't know can't hurt you? Wrong.

With no published safety data from drinking low dose antibiotics put through a beer fermentation, the answer is pretty clear. 1. You should have finished taking your prescription and 2. Adding it to beer and drinking such beer is a plainly terrible idea with questionable safety.

Sorry for all the nonsense

Happy to help!