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What dissolves cellulose but doesn't react with amines or esters?

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seep

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I'm trying to increase the extraction-yield of certain alkaloids. It is necessary to completely depolymerize the polysaccharide.

DMF is out of the question because A/B extractions hydrolyze it to dimethyl ammonium and methanoate (and so best case scenario: side products and lower yields).

I'm taking a look at NMO but I've never worked with it.

(please nothing as recondite as cupriethylenediamine or cadmiumethylenenediamine (Wiki's 2 other suggestions), unless there's good reasons to look into those as well).
 
If you need to depolymerize it, simply dissolving it will not do the trick... none of those compounds actually depolymerize it, they just dissolve it (while leaving the polymer chains intact)
 
TheAzo said:
If you need to depolymerize it, simply dissolving it will not do the trick... none of those compounds actually depolymerize it, they just dissolve it (while leaving the polymer chains intact)
Click to expand...

Damn. Yes, that makes sense, since it would no longer be cellulose if it depolymerizes.

So then cellulose solvation just involves disruption of hydrogen bonding, leaving you with an extremely fine analogue of spaghetti. I guess this'll do (I guess), cuz refluxing in HCl or HBr would destroy some of the desired extracts.
 
tried MeOH in a soxhlet extractor? dunno what alkaloids you have, and what the matrix looks like...

i once did mimosa hostilis root bark powder like this. wet the RB with a lil' bit of ammonia, stuff in soxhlet, run overnight. then rotavap the MeOH, acidify, remove fats with pentane (a reverse acid/base extraction, really)

beautiful xtals from pentane at -20.
 
Aloysius said:
tried MeOH in a soxhlet extractor? dunno what alkaloids you have, and what the matrix looks like...
Click to expand...

I've jury-rigged a similar apparatus and used ethanol as a solvent (with different bases for catalysis), but the yields were poor, partially (I think) because the matrix is fibrous stalk (cane-like) which even after pureeing, drying and grinding seems to retain a heroic ability to adsorb the desired alkaloid even after exhaustive refluxing and siphoning.

I won't name the plant (paranoid); the alkaloid is chemically similar to ibogaine but with an ester (that is: indole + azabicyclic complex + ester)
 
Yohimbine?

200px-Yohimbine_structure.svg.png


Mitragynine?

200px-Mitragynine.png
 
^ & ^^^^: Rate (and a bunch of other things)?

In terms of cellulase enzyme alone: ~80 grams (25 kilounits) of cellulase from Aspergillus niger (Sigma) depolymerizes a sheet of printer paper per hour (2-hour incubation time, body temperature, pH 5.0).

Anyone here worked with cellulase before?
 
'Depolymerize' cellulose will be next to impossible without touching the contained alkaloids. The classic chemical way to do this would be boiling in concentrated HCl. The suggested cellulase is already more elegant.

Another really useful approach would be microwave-assisted extraction. Because microwave-radiation usually heats the sample from the inside (in contrary to any conventional heating method, where the heat is applied from the outside), it creates positive pressure in the alkaloid-containing parts of the sample (whichever these may be; oil container, fatty tissue, ...), thus simply popping them. This allows for a more efficient extraction with respect to both yield and required time.

A very useful example for this method was published not too long ago (with pictures, who show how the cells were 'popped' open):"Microwave-Assisted Extraction of Piperine from Piper nigrum" in: Ind Eng Chem Res 2002, 41(10), p.2521 (DOI: 10.1021/ie010359b).


Peace! - Murphy
 
i dont know about rates with microbes, probably pretty slow. i would guess that fungus (aspergillus) would be slower than prokaryotes because it probably grows slower.

i was thinking you could culture whatever microbe in a broth and put in the plant material as a slurry. it might take a while, but once you had the strain you could culture it indefinitely and get several tanks going. then it could just sit for days/weeks/however long. probably cheaper than buying enzymes over the long run if you are looking to extract a large amount.

one thought, the aspergillus that makes the enzyme you where talking about is probably genetically engineered for that purpose. that would be the strain to get.

one other thought would be culturing the stomach juices from a ruminant, like a goat or something. ruminants use several types of microbes to break down cellulose.
 
^I forget which one ruminants have. I know termites have little guys in them called Trichonympha. Easy to remember because it sounds like nympho tricks. This is in line with my strategy for medical testing:

bones of the wrist: Scaphoid, Lunate, Triquetrum, Pisiform, Trapezium, Trapezoid, Capitate, Hamate:
Slowly Lower Trixie's Panties To The Curly Hairs
​
cranial nerves: Olfactory, Optic, Oculomotor, Trochlear, Trigeminal, Abducens, Facial, Vestibulocochlear, Glossopharyngeal, Vagus, Accessory, Hypoglossal:
Oh Oh Oh To Touch And Feel Virgin Girls' Vaginas And Hymens
​


The microwave thing is extremely cool:

To increase the extraction efficiency and improve the recovery of piperine from pepper, further experiments were carried out in the microwave cavity by combining irradiation and extraction steps in a single unit . . . For the second technique, the microwave oven was modified. The modified setup (Figure 1) contained a glass vessel (15 cm height and 2 cm internal diameter) within the oven cavity, with a provision for continuous nitrogen sparging to maintain an inert atmosphere inside the vessel. The gas was sparged into the suspension of the raw material in an organic solvent, and the flow rate was maintained just enough to keep the particles in suspension. No additional hole was bored into the cavity. The holes present in the roof of the cavity and the provision present in the oven for insertion of thermal probe were used to pass the polypropylene tubes to carry the vapors formed from the extraction vessel. The effluent gas was then passed through two liquid-nitrogen traps, outside the oven cavity, to trap any volatile material including the organic solvent vaporized from the extraction vessel during the microwave treatment.
Click to expand...

My microwave doesn't have thermometer ports. What I can do is remove the door, punch 2 holes near the top of the pane, punch 2 holes through a similar pane, affix this pane to the interior side of the door (holes down), run the tubing through the holes and reattach the door. This'll keep the radiation inside the microwave.

I don't fancy using liquid nitrogen though.
 
lol! yeah the hardest thing about learning medical stuff is the memorization for sure.

with the microwave, just stand on the other side. not much would come out through the hole anyway, and there would be a significant proximity affect.

so, are you looking to extract enough of this compound for your own limited use, or larger amounts? how much plant matter would you need if you could extract 50% of the compound?
 
^The liquid nitrogen is not really needed for a microwave-assisted extraction. In the provided example it just served to protect the employed vacuum pump from volatiles. The desired alkaloids should stay in the reaction vessel.

When trying to manipulate a household microwave oven for such a procedure (which is actually possible!) you should take maximum care that no radiation leaks out of the apparatus. Microwaves can easily blind you or cause other harm. I recommend to consult a book about physics of electromagnetic radiation first, to get an idea how to trap leaking radiation.

But as I said, it is possible.

If you happen to try this out, please report back. But don't hurt yourself! ;)


- Murphy
 
You want alkaloids from plant material? disrupt the cell walls with ultrasound (you can get such devices for cleaning things), then run through a column of ion exchange resion (pharma industry uses Amberlite IRC-50(H) for alkaloid extraction.) Beauty of this method is hte ion exchange resin can be regeneratee after use.
 
Or grind them thoroughly with a mortel with a few drops of water, that should get the juices out, add solvent with chemical properties that solvate the substance you want to extract
 
fastandbulbous said:
You want alkaloids from plant material? disrupt the cell walls with ultrasound (you can get such devices for cleaning things), then run through a column of ion exchange resion (pharma industry uses Amberlite IRC-50(H) for alkaloid extraction.) Beauty of this method is hte ion exchange resin can be regeneratee after use.
Click to expand...

that sounds pretty sweet. quite expensive?
 
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