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What's the problem? Enzymes degrade slowly over time; they don't go away suddenly after 8 hours. Different enzymes in solution will lose activity at different rates, and temperature and buffer content are other factors that will determine the rate of loss of activity. But apparently the Walker system was deemed to lose enough activity by 8 hours that he advises discarding the solution after that much time. You have to take his word on that (or not), because none of us have done the experiment. You don't need Stephen Hawkin(g)s for that. |
Rodman,
Yep, that's exactly what I had in mind! :)
Cool thread ... and rather unexpected too. Who'd have thought? |
This Topic needs some Moroccan Black, 16 beers, 5 audiophiles, 2 chemists and Steve Hawkins.
I will arrange this get together and post the conclusion |
Biologist here. All enzymes ARE proteins. It is folly to make generalizations about the lifespan of the activity of an enzyme, because they are all different. However, they can be grouped based on their specificity, half-life (time it takes to lose half of the specific activity), resistance to denaturation, etc. In most cases, temperature has a directly proportional effect on half-life. As I understand it (from reading on the internet, so who knows?), the enzymes used in record cleaning kits are of a very tough and stable variety, called proteinases because they can "devour" other proteins. They are active in the presence of ionic and/or nonionic detergents, which completely kill other more fragile classes of enzymes. In the case of the Walker kit, he supplies the enzyme in powdered form, which is very stable unless it's subjected to excessive heat, etc, for long periods of time. So the clock does not start until you mix it with the supplied water. As to the more pertinent question of what are we doing when we clean our records withe enzymes. I wonder about that too. Possibly there are molds and vinyl-loving bacteria that can grow in the grooves. The enzymes commonly used have some activity against bacterial and probably fungal cell walls. |
But the query is questionable. What should be asked is: in the absence of biological contamination on my records, what effect do enzymes have as cleaners?
The answer is very simple. None whatsoever. Well. Duh! ;-) Punkuk, I can highly recommend AIVS cleaning products. There are others as well, but I like AIVS very much. |
Punkuk- A little Comet w/Clorox on that Brillo Pad will keep the mold/mildew down as well. |
As a professor of molecular biology and physics, I'm happy to weigh in on this subject. DNA enzymology is a major focus of research in my lab; we study enzymes that recombine (i.e., cut, rearrange, and rejoin) DNA in E. coli and yeast.
i.) Most enzymes progressively lose activity at room and physiological temperature. This is because enzymes are proteins, long-chain molecules that have complex three-dimensional folded shapes. The native 3-d shape is required for catalytic (enzymatic) activity; however, the forces that hold these shapes together are weak and therefore easily overcome by random thermal motions. Increased motion at elevated temperatures not only makes the folded state less stable, but also accelerates the rate of unfolding.
ii.) Unfolding is also made more favorable by dilution. This is because at high concentration proteins have "less room" to unfold due to the larger volume fraction occupied by protein molecules instead of solvent. Once an enzyme solution is diluted, however, the local influence of enzyme molecules on one another is dramatically reduced. The dilution problem is exacerbated by surface inactivation, whereby the greater exposure of enzyme molecules to the surface of a test tube increases the probability that the molecule will stick to a surface and become inactivated.
The way that biochemists generally address the problems associated with dilution is by including high concentrations of an inert protein such as bovine serum albumin (BSA) in their diluted enzyme solutions.
iii.) The duration of enzyme activity one can expect depends on the enzyme and also the solution in which it is suspended. Lifetimes are typically minutes to hours (not necessarily 8 hrs.). Some enzymes, such as ribonuclease A retain activity indefinitely (this is because the protein's 3-d structure is stabilized by covalent sulfur-sulfur bonds). Many, but not all, detergents destabilize folded proteins and if these compounds are present in the enzyme solution they will likely affect the time course of enzymatic activity. However, if the concentration of enzyme is high enough to start with, it may not matter much for periods of an hour or so.
FWIW, long-term storage conditions for our purified enzyme preps involve high concentrations (10 - 100 mg/mL) at -80 deg. C.
Hope this clears up some questions. |
Hey Dick- kinda like this?: (http://users.rcn.com/jkimball.ma.ultranet/BiologyPages/E/EnzymeKinetics.html) |
Crap......... ignorance was bliss.
I just wanted a recomendation on a good cleaner,
I am gonna go back to a simple Brillo Pad and some elbow grease, it has always worked in the past. |
Well, I'm not a biochemist but I do have a minor in biochemistry. Yes, enzymes DO break down over time. This process is accelerated by increasing temperature. Almost all enzymes are proteins and anything that destroys proteins will destroy enzymes as well. That said, all is not black and white. Some enzymes are more fragile than others. They will also degrade more quickly once you mix them with water. But, unless you heat them, they don't tend to become inactive all at once. The efficacy will just diminish over time.
Enzymes tend to be very specific as to what they will break down but again, some are more broad-based than others. However, in general, enzymes act to break bonds at specific places (usually on other proteins). What this means for the vinylphile is that, while you might break down and wash away a lot of protein (mold, mildew, etc.) you are not likely to get it all with the enzyme treatment.
Dick |
I'm continually amazed that so many answers to technical questions on this and other audio forums (fora?) come from people who don't have a clue what they're writing about. I don't see a statement from a knowledgeable chemist or biochemist here at all, so all that has been achieved is the exchange of uninformed misinformation.
So long as they are not subjected to heat or organic solvents (in particular),commercially-available enzymes do not loose their biological and catalytic activity.
But the query is questionable. What should be asked is: in the absence of biological contamination on my records, what effect do enzymes have as cleaners?
The answer is very simple. None whatsoever. |
I'm still brushing my teeth with AIVS....they're whiter than ever! |
Depending on the type of enzymes, they do start being less effective after their use by date/time. It's like the carton of milk it doesn't turn bad the minute the second hand goes past it's use by date! |
The enzyme in question may be deactivated by oxygen in the air. |
Doesn't seem to make a lot of sense. If the enzymes they use are only good for 8-10 hours, why wouldn't they "die" sitting in the bottle before they even get to you? |
Dan ed is correct--enzymes don't die --but Albert the dead cleaner is the chlorox used to clean up the murder seen --hence the name :)--rich Thank goodness someone else other than me is teasing a bit in the forums. It's getting as dry as unbuttered popcorn around here :^). Where's Marco (Jax2) when we need him? Thanks Ras422 |
My understanding regarding the stuff I use (Bugtussel) is that it's air activated and doesn't deteriorate in storage, but I'm going to ask them specifically and see what they say. |
Dan ed is correct--enzymes don't die --but Albert the dead cleaner is the chlorox used to clean up the murder seen --hence the name :)--rich |
Yeah, this topic was discussed before. IIRC, the enzymes that Walker uses may be of a type that lose effectiveness after a few hours. But I can't really say for sure. Enzymes don't really "die" per se, they are organic compounds but not living organisms.
The enzymes used by AIVS seem to still be effective after several months of siting next to my RCM cuz they're still cleaning my records. |
How do we explain liquid detergent with enzymes? I see them for sale at stores, are they selling "dead" cleaner? |
So after they die are cleaning fluids that use ennzymes ineffective?
If so this is huge for all those sellers of enzyme based cleaning products.
How does this affect liquid concentrate vs. solid based cleaning products? |
No, it's true. I work with enzymes. We keep them refrigerated as well. |
