Redox processes are an essential component of fermentation. Lactic acid can in principle be oxidized (meaning it is acting as a reducing agent) to the metabolic keystone
pyruvic acid - which, incidentally, decomposes fairly readily (e.g.
https://www.physicsforum...id-decomposition.839140/) to acetaldehyde and carbon dioxide if left alone in solution.
Besides all that, we're looking at a fairly complex, biologically active mixture so even the process of attempting to produce analytical isolates is likely to change what we're looking at. The Manske is likely to precipitate at least some of the compounds of interest, and the presence of sodium lactate in the remaining solution is unlikely to confound crystallization because it is very soluble.
It will be interesting to see how the effects Manske'd alkaloids compare with those of the whole fermented brew.
On a slightly related note, I made an observation while taking far too long to process some rue tea earlier this year.
My main focus was getting the brew to a crystal-clear state before proceeding further. This aim was fraught with the usual fine suspended solids and compounded by a persistent pectin haze. Addition of a small amount of alum (potassium aluminium sulfate)ª solution had had
some beneficial effect but it was still not wholly satisfactory.
The weather warmed up and my brews all became inoculated with a
Trichoderma mould. As chance would have it, Trichoderma can be an abundant producer of cellulase: this observation became apparent as several of my filter papers literally dissolved away while in contact with the - now technically fermented - brew.
The happy upshot of this was that the cellulase also seemed to be active against the pectin (which, rather, may have been a soluble hemicellulose?) - the solutions began to clear. Before the mould got out of control and started to produce spores, it was brought to an abrupt halt by the addition of concentrated acetic acid to make a 1% solution. Again fortune shone upon the haphazard experiment and the mould congealed nicely, taking some more of the sediment with it. This also seemed to be sufficient to inactivate any remaining cellulase.
After standing for several more weeks (while life got in the way), the once-again-filtered brew deposited the remainder of its extremely fine sediment leaving a now truly crystal clear solution. When a light beam was shone through it, it was no longer visible from the side (no
Tyndall effect).
I'm reluctant to use Trichoderma-treated brew, however, as I'm uncertain of its toxicology. Since it's already acidic I'm contemplating Manske as the next step, but it is very dilute (50g seed in ~5L brew.) On account of this acidity, it seems daft to add alkali as some suggest. (Sorry for the slight thread-hijack!)
ª Alum is often included in tradition esphand incense from the middle eastern grocer's store and is well known for being an astringent, mordant and coagulant.
βThere is a way of manipulating matter and energy so as to produce what modern scientists call 'a field of force'. The field acts on the observer and puts him in a privileged position vis-à-vis the universe. From this position he has access to the realities which are ordinarily hidden from us by time and space, matter and energy. This is what we call the Great Work."
β Jacques Bergier, quoting Fulcanelli