Passionflowers

[Lupus]

I recently aquired a P. caerula (not sure of the spelling) plant, it grows wild in my area. Anyway, I was wondering if the plant has similair effects to the others, such as P. incarnata? Is it safe?

Note: the plant has 5-lobed leaves and white flowers w/ blue crowns.

[Torsten]

I believe that all passifloras have such alkaloids in varying quantities. However this one also has a fair amount of cyanide in with it and this may spoil the experience ;-)

[Lupus]

Would there be a way to remove the cyanide?, Cyanide extraction?, to make the plant useable? Would a lot of cyanide come with it if it were extracted for the useable parts?

[Torsten]

Cyanide will be liberated into the air if you boil an acidic solution of it.

A 2-phase extraction with at least 3 phase changes should get rid of most of it anyway.

[Guest theobromus]

It would be faster and more complete if you mashed the fresh plant in a food processor and allowed the plant's own enzymes to release the hydrogen cyanide. If you then dry the mash in thin layers on glass baking trays at 35°C the hydrogen cyanide will all evaporate if you ensure it becomes totally dry for a while.

You can die from inhaling hydrogen cyanide gas so be very careful with good ventilation. Immediately the plant material is crushed it will start to evolve hydrogen cyanide in quantity. Dry the material outdoors or in a room with a powerful extractor fan (and fan blowing onto the plant material, preferably) and fresh air supply. Do not breathe in near the plant material. Wash all tools used for processing.

[Lupus]

How much hydrogen cyanide would be evolved?

What type of acid would I use if I were to attempt your method Torston? HCl?

Is there any way to contain the hydrogen cyanide (dissolving in water? <- forms Hydrocyanic acid?), so I wouldn't need a fume hood or release the hydrogen cyanide into the atmosphere?

[Torsten]

As plant material can be alkaline, there is no guarantee that the cyanides would be evolved as hydrocyanic acid gas, but rather could be locked into the herb (as is the case with acacia phyllodes).

The amounts of HCN released ae minimal from passifloras and good ventilation in the kitchen is plenty. Just don't hang around the pot and sniff the steam ;-)

if you were to do this with fresh bitter-almond meal you could easily poison yourself though.

You don't want to contain the HCN, as this is exactly what you're trying to get rid off and venting into atmosphere is a good way of doing it (don't worry, won't cause any harm to nature in small quantities as it decomposes quickly).

A good acid to use would be one that is edible, such as vinegar or citric acid (lemon juice).

[Guest theobromus]

Passiflora caerulea can produce 1 mg/g of HCN from the bruised fresh leaf. This would mean that one kilo of the fresh leaf could produce enough HCN to kill at least 20 people. Worth a little caution, I think, Torsten.

[Torsten]

So Theo, you're saying that 1g of this passiflora could kill 20 people? That would make it one hell of an efficient poison.

The cows on our property eat heaps of the stuff when they get hungry and are still alive (athough poisoning has been reported for this species).

Where did you get the ref for 1mg/1g? What's the fatal dose for HCN?

[Guest theobromus]

No, Torsten, I quite clearly wrote that one kilo of the fresh leaf would produce enough HCN to kill 20 people. I know of more efficient poisons.

The reference for the figure of 1 mg/g is from Phytochemistry (1982) 21; 2277

It did seem a little strong to me as most Passiflora species seem to only have that level of cyanogenic glycoside, producing a twentieth of that amount of HCN. Even then it would still be wise to be cautious when processing large quantities.

As for your cattle, we all know the problems with animal models. Birds can eat as much HCN-laced fruit as they please. The Merck Index states that the average fatal dose of HCN in humans is 50 to 60mg. Death may result after minutes of exposure to 300 ppm in the air. Exposure to 150 ppm for ½ to 1 hour "may endanger life".

[Lupus]

So, is there a safe way to do this? Every post seems to be getting bleaker and bleaker. How does this sound:

I take the plant material and boil it, outside on a hotplate, in an acidic solution. This releases HCN into the air . So, if I use vinegar it should convert the CN into HCN, which is gaseous, leaving behind Acetate? After this I rinse the material and dry it? Woulden't just shy of everything good be gone by then? Is there a good way to convert the HCN(g) to HCN(l)?(Making HCN acid, much safer than gas).

P.S. Thank You both for your replies so far . I have learned more about this plant from you two than I am sure I could have found on my own.

[Torsten]

Sorry Theo, misread your post! Thanks for the extra info.

I take the plant material and boil it, outside on a hotplate, in an acidic solution. This releases HCN into the air . So, if I use vinegar it should convert the CN into HCN, which is gaseous, leaving behind Acetate?

Looks good up to here.

After this I rinse the material and dry it?

You've already extracted the alkaloids into the acidic solution, so at this stage you can chuck the solids and work with the liquid.

Woulden't just shy of everything good be gone by then?

You don't have to boil for long as the conversion is fairly quick. It won't harm the alkaloids much at all.

Is there a good way to convert the HCN(g) to HCN(l)?(Making HCN acid, much safer than gas).

If you kept it as a liquid, then it would be in the vinegar solution together with your alkaloids. This is not desirable. By venting it as a gas you have got your solution as clean a possible.

BTW, all this applies to anyone contemplating the same procedure with acacia foliage, especially longifolia.

[Lupus]

Is there a good way to convert the HCN(g) to HCN(l)?(Making HCN acid, much safer than gas).

What I mean here is that I would pass the gas that is evolved through a condenser and keep it seperate from the other liquid. I read that HCN is a liquid at somewhere around 26 deg.C. I would then dissolve in water to convert to HCN acid.

You've already extracted the alkaloids into the acidic solution, so at this stage you can chuck the solids and work with the liquid.

So, how would I continue from here. Is it clean enough to use or should I try adding more acid to get it to react more and evolve more gas? should the liquid be dried into a gum/powder?

BTW, how would I use the end result? I have studied chemistry and alchemy for some time but it has all been theoretical until now. So I am kind of new to the practice of doing plant extractions.

[This message has been edited by Lupus (edited 18 October 2000).]

[Ed Dunkel]

HCN is liquid at 26ºC and solid at -14ºC.

I would use chilled water through a condenser to condense it out but you might as well release it to the atmosphere if you are working with small amounts then handling a highly toxic liquid that would vapourise on a warm day!!

E D