Sciencemadness Discussion Board

It's Black walnut time again - suggestions on what to do with them?

RogueRose - 8-9-2018 at 18:28

I have enough black walnuts on my property to probably fill a 20 ton dump truck over the course of the season (not 20 tons and the aren't dense). The problem is that most are located in the woods with thick underbrush and ground cover, so they are difficult to collect, except in grassy areas where we mow.

These are the Eastern Black Walnuts - https://en.wikipedia.org/wiki/Juglans_nigra

The plant is rich in Juglone which appears in roots, stem, bark and I think especially the green husk.
https://en.wikipedia.org/wiki/Juglone

I know some people make tinctures with the walnut husks, extracting with ethanol I believe (IDK if methanol or IPA would work if using tincture for external uses like for ringworm). The tincture is supposedly a powerful deworming medicine and I think it also acts as a disinfectant for bacteria and possibly some other nasties like parasites.

The husks also make a great dye if you want a nice earth brown color, though that isn't high on my list. The dried husks do powder well and supposedly retain the juglone and tinctures can later be made from that. I've used the powder as a colorant in soaps and I wonder if it has anti-microbial properties as well (very interested in this, especially if it would fight ringworm or other skin parasites/bugs/etc) - or if infusing the soap with the tincture would be a better route to get this effect.


If anyone has any desire to play around with this stuff, I'd be happy to send you some fresh green husks (they brown quickly like cut apples) or dried husk - they turn to powder in blender or processor.

I know that lots of plants have problems growing around walnut trees due to the toxicity of juglone in the soil and thus is sometimes used as a herbicide. I have a contentious battle with the landlord who uses glyphosate and 2,4-D all around the property many times a year (I HATE THIS!!!) and I would be happy to find an alternative, possibly juglone could be effective maybe in combination with strong acetic acid (or peracetic acid..?) and or NaOHCl. I'd prefer NaClO3 for the gravel driveway (1/2 mile long & HUGE parking area) but it's impossible to find - totally ridiculous!

IDK what juglone looks like extracted, if it can be isolated as a salt, but that would be interesting and a fun experiment to carry out.

So if anyone has any suggestions or experience with black walnut I'd appreciate hearing what you have done, or what you considered doing.

symboom - 8-9-2018 at 19:19

Quote to find an alternative, possibly juglone could be effective maybe in combination with strong acetic acid (or peracetic acid..?) and or NaOHCl. I'd prefer NaClO3 for the gravel driveway (1/2 mile long & HUGE parking area)

Sounds like you dont need
Bleach and chlorate not a good idea for the water table
Underground water

to run off when it rains it might make even more areas baren
An organic helpful pestiside breaks down in the enviroment at a predetermined rate so it doesnt kill more things which it seems like the walnut extract is just fine for.

[Edited on 9-9-2018 by symboom]

[Edited on 9-9-2018 by symboom]

UC235 - 8-9-2018 at 20:44

This is interesting if you're any good at french. https://archive.org/stream/bulletindelasoc181frangoog#page/n...

My french is mediocre at best and needs supplementation with google translate, but here's my stab at the relevant parts in english with some adjustment so it reads more smoothly.


Juglone crystallizes in bright, brittle, yellow-red prismatic needles, soluble in ether, chloroform, benzene, hot acetic acid, carbon disulfide, petroleum ether. It is less soluble in alcohol and very slightly soluble in water. It melts at 154C.

Preparation- I Vogel and Reischauer.
The authors extracted with ether, the juice of walnuts recently prepared. The ethereal solution is shaken with a perfectly neutral solution of copper nitrate until the liquid has taken a blood-red coloration. The ether layer was decanted, and, after having filtered the copper solution, nitric acid was gradually added to it, and the color changed to greenish-blue. The juglone is thus set free, and it is sufficient to shake the mixture with ether and allow it to evaporate to obtain very pure juglone.

II. The authors mentioned the possibility of obtaining juglone by sublimation of the ethereal extract of the fruit.

III. The third method which is the one currently used to prepare juglone, was described in 1885 by Bernthsen and A. Semper. Ripe walnuts in September, coarsely ground, are soaked for several days in ether, in proportions of 4kg nuts to 3kg ether.
The resulting greenish-brown solution is then oxidized using the following chromic mixture:

10g Potassium Dichromate, 13g sulfuric acid monohydrate (?. That would be about 84% acid), 500ml distilled water.

After the oxidation, the solution becomes reddish yellow, the hydrojuglone having turned into juglone. The ether is distilled and the residue taken up in a small quantity of boiling ether, filtered hot, and evaporated. The residue is taken up in chloroform and mixed with an equal amount of petroleum ether, which eliminates a mucilagenous material which appears to influence the crystallization. After filtering, the solution is evaporated under vaccuum to give juglone.

The procedure of Vogel and Reischauer has the advantage that it gives a very pure product, but the yield is small.

Juglone is an extremely alterable material. It is reduced with great ease and is transformed into hydrojuglone. It also decays very quickly when in contact with water or alcohol. In several day old fruit, the decomposition is already very appreciable. When we express these fruits, the juglone, being found not only in contact with water, but also with the abundant organic matter which constitutes a strongly reductive medium is transformed almost completely into hydrojuglone after a few minutes of rest.

The extraction of the juice by means of ether then provides a liquid very rich in hydrojuglone that contain only traces of juglone.

The procedure of Bernthsen and Demper furnishes a much higher yield. By oxidizing the ethereal extract of the pericarps, we obtain the totality of the juglon contained in these organs, either in the state of juglone, or in the state of hydrojuglone. However, the product thus prepared is very impure.

The juglone obtained by this process in commerce is yellow green and can be prepared in a greater state of purity, through many crystallizations in various solvents. It is very yellow red at the time of its preparation but it does not take long to decompose and within a few days of preparation, it is partly converted into hydrojuglone and has the greenish color that compound.

New process - first method. Preparation of juglone from fresh husks.

The nuts should be harvested with care, avoiding as much as possible, too many crushed pericarps. They should be detached at the time of extraction and immediately immersed in the ether.
These precautions are intended to prevent the decomposition of juglone and transformation into hydrojuglone. The ethereal solution thus obtained is very strongly yellow in color. The ether is distilled off and the residue is immediately taken up in benzene. This step leaves many impurities insoluble, among which is most of the chlorophyll. The benzene extraction should happen immediately after the evaporation of the last traces of ether, since juglone, which is impregnated with water and various organic matter at a fairly high temperature, would decompose rapidly.

The benzene is distilled and the residue of the evaporation is extracted by means of the following mixture:

Nickel Acetate 100g, Calcium carbonate 10g, Distilled Water 1000g.

Juglone forms with acetate of nickel, a combination that is colored red-violet and soluble in water. Decant the solution and the extraction is continued until the last addition of nickel mixture no longer produces a violet color. At this time, all of the juglone has been changed to nickel salt, The combined solutions are filtered and a 10% acetic acid solution is added until the violet color disappears and is replaced by a green tint. Then, the solution is extracted with ether or chloroform to extract the liberated juglone. On distillation of the solvent, pure juglone is obtained which can be recrystallized from benzene.

This first method gives very good results. It has the advantage of being very fast, requiring only a few uncomplicated steps. It provides a very pure product but can only be applied for a short period of the year. The various solvents can be recovered by distillation and the nickel acetate by evaporation of the solution.

Second method- Preparation of juglone from dried husks or those that have been previously harvested.

When nuts were harvested a few days prior, the pericarps, which were initially green, quickly browned and their color finally turned dark brown. When the nuts have been separated from the rest of the fruit, the browning is even faster. These transformations in the appearance of the fruit are due to profound changes in its chemical composition.
It is such for the juglone which alone interests us here. The content, which was very high in the fresh husk, drops very quickly and becomes nothing after a few weeks. These husks, being subjected to various tests for the presence of oxynaphthoquinones, give negative results.

[Honestly, I'm getting pretty tired. tl;dr The nuts/husks (It's not clear to me, maybe a better french speaker can help) are extracted with ether. The ether is distilled and the residue dissolved in benzene, which dissolves all the hydrojuglone but leaves a bunch of other crap behind. They distill the benzene, and redissolve in ether. The ether solution is oxidized with the chromic acid mixture from before. This is done a second time to assure conversion to juglone. The ether layer is decanted and washed many times with distilled water. The author believes traces of chromium salts cause decomposition of the product. The ether is distilled. The residue is still very impure and will decompose on standing. The nickel acetate mixture from the previous method is used to extract the residue, is acidified as before, and extracted with ether or chloroform. The residue is pure juglone and can be recrystallized from benzene.

[Edited on 9-9-2018 by UC235]

RogueRose - 8-9-2018 at 21:53

Quote: Originally posted by UC235  
This is interesting if you're any good at french. https://archive.org/stream/bulletindelasoc181frangoog#page/n...

My french is mediocre at best and needs supplementation with google translate, but here's my stab at the relevant parts in english with some adjustment so it reads more smoothly.


II. The authors mentioned the possibility of obtaining juglone by sublimation of the ethereal extract of the fruit.

III. The third method which is the one currently used to prepare juglone, was described in 1885 by Bernthsen and A. Semper. Ripe walnuts in September, coarsely ground, are soaked for several days in ether, in proportions of 4kg nuts to 3kg ether.
The resulting greenish-brown solution is then oxidized using the following chromic mixture:

10g Potassium Dichromate, 13g sulfuric acid monohydrate (?. That would be about 84% acid), 500ml distilled water.

After the oxidation, the solution becomes reddish yellow, the hydrojuglone having turned into juglone. The ether is distilled and the residue taken up in a small quantity of boiling ether, filtered hot, and evaporated. The residue is taken up in chloroform and mixed with an equal amount of petroleum ether, which eliminates a mucilagenous material which appears to influence the crystallization. After filtering, the solution is evaporated under vaccuum to give juglone.

The procedure of Vogel and Reischauer has the advantage that it gives a very pure product, but the yield is small.

Juglone is an extremely alterable material. It is reduced with great ease and is transformed into hydrojuglone. It also decays very quickly when in contact with water or alcohol. In several day old fruit, the decomposition is already very appreciable. When we express these fruits, the juglone, being found not only in contact with water, but also with the abundant organic matter which constitutes a strongly reductive medium is transformed almost completely into hydrojuglone after a few minutes of rest.

The extraction of the juice by means of ether then provides a liquid very rich in hydrojuglone that contain only traces of juglone.

The procedure of Bernthsen and Demper furnishes a much higher yield. By oxidizing the ethereal extract of the pericarps, we obtain the totality of the juglon contained in these organs, either in the state of juglone, or in the state of hydrojuglone. However, the product thus prepared is very impure.

The juglone obtained by this process in commerce is yellow green and can be prepared in a greater state of purity, through many crystallizations in various solvents. It is very yellow red at the time of its preparation but it does not take long to decompose and within a few days of preparation, it is partly converted into hydrojuglone and has the greenish color that compound.

New process - first method.

The nuts should be harvested with care, avoiding as much as possible, too many crushed pericarps. They should be detached at the time of extraction and immediately immersed in the ether.
These precautions are intended to prevent the decomposition of juglone and transformation into hydrojuglone. The ethereal solution thus obtained is very strongly yellow in color. The ether is distilled off and the residue is immediately taken up in benzene. This step leaves many impurities insoluble, among which is most of the chlorophyll. The benzene extraction should happen immediately after the evaporation of the last traces of ether, since juglone, which is impregnated with water and various organic matter at a fairly high temperature, would decompose rapidly.

[Edited on 9-9-2018 by UC235]




Thanks for the replies!

What I find interesting is that it tells of all the solvents that are good at extracting juglone and says "less soluble" in alcohol and "very slightly soluble in water" - which I find interesting b/c if you look for the extraction methods, those are the ones people say to use on videos and such.

The paragraph bolded is of interest as I'm not sure I'm understanding it correctly. It seems to say that juglone decays quickly by contact with water and alcohol - which makes me wonder what is really in these tinctures. Does it mean that it decays into hydrojuglone (looks like hydroxyjuglone as per wiki...) and if so, is that the stuff that works well for the various health treatments?

I was wondering if it was possible to harvest the nuts and remove the husks and dry them out and then later extract the juglone. I know they sell dried husk to make tinctures from, but after reading the alcohol/water thing, that could be all BS as well. Wiki states that the color change from green to dark brown/black is the process of

The wiki article is even more confusing:

Quote:

Before oxidization, juglone exists in plants such as walnuts in the form of colorless hydroxyjuglone, with both O groups replaced with OH groups. This is rapidly oxidized to juglone once exposed to air. The evidence that hydroxyjuglone is readily degraded is most apparent in the color change of walnut hulls from yellow to black after being freshly cut.[14]


So does this mean that the original product in the plant is hydroxyjuglone and then when it is degraded (by air, water) it is then juglone?

I need to figure out pretty quick how I have to process these b/c they are falling fast. I did find pure juglone for sale and it is only $92 for 250mg! kind of pricey imo so it would be interesting to see if I can isolate it.

It says to use "ether" but what should I use, diethyl, dimethyl or petroleum ether? I wonder if heptane would harm the compound.

[Edited on 9-9-2018 by RogueRose]

Metacelsus - 9-9-2018 at 05:50

"Ether" means diethyl ether. You could probably substitute ethyl acetate, chloroform, or toluene. I expect that petroleum ether and heptane would not dissolve much juglone or hydrojuglone, being too nonpolar.

UC235 - 9-9-2018 at 10:03

Considering juglone is orangey in color, the browning of the hulls is probably due to something else. Polycondensation of phenolics tends to give brown crap so Im hardly surprised, especially if walnuts have a lot of peroxidase enzymes present.

Apparently juglone is mostly stored as hydrojuglone (1,4,8-trihydroxynapthalene) and a very labile glucoside thereof since high concentrations aren't healthy for the walnut tree either. It is seemingly extracted easily from very fresh nut husks, but on standing is mostly reduced back to hydrojuglone and probably a good deal is polymerized to crap. Hence the elaborate extraction methods used in the french paper.

Ether means diethyl ether.

Sigma has juglone for $54/g, so it's not super valuable.

I'm unsure where wiki is getting the 2-4% figure. The paper they link is about normal walnuts and reports a maximum of about 40mg/100g which is 0.04%

This paper reports about 0.3% of fresh weight. https://www.apsnet.org/publications/phytopathology/backissue...



[Edited on 9-9-2018 by UC235]

andy1988 - 28-9-2018 at 14:58

Quote: Originally posted by RogueRose  
I have enough black walnuts on my property to probably fill a 20 ton dump truck over the course of the season
...
So if anyone has any suggestions


I saw this article on lignin today and thought of this thread.

Quote:
"Walnut is the common agriculture fruit in China, which is processed to drink or oil. Unfortunately, the walnut shell with abundant lignin is waste after the process. Lignin is an amorphous aromatic network polymer, a renewable and non-toxic resource, which has the potential application as a basic raw material for the chemical industry [1].

SHlTnipplesmadeofeggs - 1-10-2018 at 07:55

This doesn't have anything to do with extracting them, but I've heard of the hull flour being used in place of coffee creamer to make enormous fireballs (shoot compressed air through it and light it/dust explosion)

Magpie - 2-10-2018 at 07:16

I love black walnuts. Excellent for eating raw and for using in ice cream.

I've often wondered how the intensive labor of obtaining the meat could be improved. First there is the problem of removing the husks. Could soaking in lye be used? Or some mechanical means like rubbing them between two screens might be practical. Then some type of crusher is needed to break up those very hard shells. Then a sorter is needed to separate the shells from the meat.

Does anyone have any better ideas?

[Edited on 2-10-2018 by Magpie]

S.C. Wack - 2-10-2018 at 13:48

When I was a kid there was a local buyer for the nuts and people would have their kids fill pickups, but last I checked the buyers were a ways away. Are good mass nutcrackers a trade secret? It's damn hard to open just one...the shells are ground up for abrasive powders, works great with soap...farming the trees has been recommended as economically viable (for your kids) but IDK anyone doing it.

What kind of tannin is in the hull? A large amount of gallotannin could be interesting.

zed - 3-10-2018 at 16:23

Ummm. I got a similar problem with "Ashmead's Kernel" apples this year.

So many.

I have been slicing 'em up small, and heat-treating the slices inside of commercial available containers called pie shells. Baking.... I suppose, is what you humans call the process. About 20 pies so far. Very satisfactory.

There must be a convenient way to crack those black walnut shells. Like maybe, a hydraulic press? I have a 20 ton unit via Harbor Freight.

If you can get 'em open. I suggest synthesizing "Mexican Wedding Cookies".
https://honest-food.net/black-walnuts-and-holiday-cheer/





[Edited on 4-10-2018 by zed]

Morgan - 4-10-2018 at 06:29

This video shows a hand cranked device that seems to work OK. It comes with eyewear.
World's Best BLACK WALNUT NUTCRACKER! The ONLY Hand Crank Nut Cracker that cracks Black Walnuts!!!
https://youtube.com/watch?v=h_SBK2AUc1M

Another design that gets the pieces out in halves. Probably could use a vacuum to catch the dust which might not be good to breathe over time. And perhaps earmuffs ...

Cracking Black Walnuts with the WALNUT SAW™
https://youtube.com/watch?v=_5p8jbxUIRA

zed - 4-10-2018 at 14:41

Juglone, might make a decent hair-dye, or Henna substitute for temporary tattoos. Depending on human toxicity.

Juglone is a cousin to the pigment found in Henna.

https://en.wikipedia.org/wiki/Lawsone

[Edited on 4-10-2018 by zed]

[Edited on 4-10-2018 by zed]