The contaminants that seem to be the worst, and hardest to remove, are cigarette (or other) smoke, as well as old fluids, whether they were "record cleaning fluids" that weren't effectively removed by earlier 'cleanings' or other stuff that was wiped on the record, and over time, glued the particulates into the grooves or are themselves a form of contamination that creates groove noise. The enzymes are those purpose-marketed for record products: I used Walker's Prelude stuff for a number of years and eventually transitioned to an easier (and in my view), more effective two step process: AIVS No. 15, followed by a reagent rinse. (Frumkin, who started the company, was, like me, a lawyer; according to the lore, he worked with a chemist to develop the formulae and then sold the company to Jim Pendleton who has an engineering background). As to what's actually in the bottle, couldn't tell you. As to how effective it is (and I don't get paid for this), letting the enzyme-based fluid soak, agitate, soak, and vacuum, has proved to be very effective in getting rid of stuff that other purpose-sold record cleaning fluids didn't effective remove. (The soaking and agitating as well as the rinse step are essential). For what it's worth, though the ultrasonic cleaners I've owned can do a marvelous job - giving you a very quiet, static-free record with almost zero effort, they didn't tackle some of the problem records mentioned below. I've tried a range of different fluids (not all) and there seem to be a number of factors at play; breaking the surface tension of the fluid, to let it migrate into the grooves, how well it cleans (based on results in listening), how easy it is to remove- I remember when I used to detail my own cars, most of the detailers used 'Dawn' detergent as a 'stripper' to remove layers of old wax, etc. to begin to prep the finish for work. So, a 'standard' detergent seems a bit much for several reasons- maybe too harsh, it foams, and may be more difficult to remove. I've tried to get more information from a few of the fluid suppliers and they are usually 'mum' about the secret ingredients- not that I'm either gullible or a skeptic: I know serious archivists that swear by Photo-Flo and distilled or deionized water. Or use the formula on the LOC site based on Tergitol. I also had the impression that while alcohol might be a decent solvent, one of its chief virtues was its evaporative ability. I'm not against using an alcohol-based cleaner. I'm not claiming some 'inside' knowledge- in fact, I'd love to learn more (and have been spending some time doing the research, though I am not a chemist). My conclusions are based in large part on my experience using a variety of machines, methods, fluids , cleaning thousands of records in just the last several years and the biggest learning curve for me was not, as I said, claiming to hear the flugelhorn better on a record after using one cleaner vs. another, but struggling to clean some valuable records that still still suffered from some form of contamination-- that sounded like groove damage-- even after repeated cleanings. Some of these did clean up after cleaning them using a combination of different fluids, methods and repeated cleaning, including the use of ultrasonic machines. No one of these cleaning methods or fluids or machines achieved those results standing alone, even with repeated cleanings using one method, machine or fluid. Which leads me to the conclusion, purely based on empirical evidence from my efforts, and listening to the results (which were not subtle- the difference between noise, distortion and what I call the sound of 'groove chew') that a combination of methods is more effective in eliminating* than one method alone. As I said at the outset, I have no agenda, am pretty agnostic as to products, machines and the like. At bottom, I'm trying to come to grips with all this, and get a better understanding of it- and to share what I've learned. *Not all records will clean up even with all these efforts. Some are just damaged or noisy- either because the vinyl was noisy to begin with, or the records were damaged beyond salvaging through cleaning.