Talk:Harmine

Harmine renegerates beta cells in diabetes

There are articles about harmine regenerating beta cells and could be a cure for diabetes. https://www.healthline.com/health-news/psychoactive-plant-may-hold-key-to-reversing-diabetes-030915#3 — Preceding unsigned comment added by 89.137.77.239 (talk) 16:28, 4 January 2018 (UTC)

Why does this article contain medical advice?

Should the statement, "Individuals should not attempt to self-medicate themselves for depression using harmine," be in this article? It seems to be unnecessary, and possibly biased medical advice. In fact both passionflower and tribulus are frequenty used as herbal supplements to relieve symptoms of depression, and both contain harmal type alkaloids. Mike19772007 19:48, 16 July 2007 (UTC)

• I have edited this statement to read "Harmine, and plants containing significant amounts of harmine and other harmala alkaloids are generally not considered safe treatments for depression within the medical community" and provided reference. Mike19772007 19:11, 19 July 2007 (UTC)

MAO-A Inhibitor

Harmine is a selective and resersible MAO-A inhibitor. This means it only has an effect on tryptamines such as psilocybin and serotonin, but not phenethylamine. Mescaline is listed as a hallucinogenic monoamine alkaloid, but it is a phenethylamine, and this should be revised.

Well..., not really. This generalization is simply not true. Mescaline, for example, is also metabolized by MAO-A. More importantly, this article contains many factual errors about tyramine metabolism. Tyramine is a substrate for MAO-B. This is why there is no "cheese effect" with harmine/ayahuasca MAOI. I'll spend just a little time to do some minor editing here.Jace1 (talk) 11:16, 17 April 2009 (UTC)

Source confirmation

Currently 5th cited source is titled "Effect of moclobemide on rat brain monoamine oxidase A and B: comparison with harmaline and clorgyline." The abstract doesn't say anything about harmine but only about harmaline. Could some one confirm if this source actually deals also with harmine and this is not a mixup?--Custoo (talk) 18:11, 22 December 2014 (UTC)

Is the last step in the biosynthesis incorrect?

The graphic of the biosynthesis and the corresponding text entry indicates "In the last step V, the oxidation of harmaline is accompanied by the loss of water and effectively generates harmine."

In the graphic of the biosynthesis, looking at the main structure of the molecule, the last step indicates that it is H2 (hydrogen), not water, that is being eliminated, right? If so, the arrow accompanying the last step showing the elimination of water and the above text description of the last step would be incorrect. Wmcoco (talk) 07:15, 4 August 2023 (UTC)

Misleading description of the UV fluorescence

The concentration of dissolved harmala alkaloids is not directly proportional to their concentration as being suggested in the article's image description (see on the right):

Harmaline and harmine fluoresce under ultraviolet light. These three extractions indicate that the middle one has a higher concentration of the two compounds.

Peak emission of visible light can be observed at relatively low concentrations (~0.1-10 mM) and dies off with both dilution and concentration of the alkaloids. Concentrated solutions show some fluorescence at the edges of the glass but the bulk of liquid seems darker as absorbance quickly prevails with higher concentration - the glass in the center might actually contain lower concentration of harmalas compared to left and right glasses. Also note the brighter fluorescence at meniscus of the liquid and surface of the glass, indicating brighter apparent fluorescence at lower alkaloid concentration.

Finally, the harmine fluorescence is pH-dependendent (as noted in the article). Harmine gives indigo-blue fluorescence at pH <7.7 and yellow-green pH >8.9. The emission of harmala alkaloids in acetic acid solution will differ from neutral or slightly alkaline solutions. The emission will be further skewed by the fact harmine and harmaline have different acid dissociation constant.

The bottom line is that fluorescence behavior of harmala alkaloids is complex and their concentration cannot be estimated simply by the brightness of emitted light under UV illumination (the spectrum of UV light source also plays a role).

I can provide more illustrative images of solutions having known concentration and alkaloid composition, if desired.

The absorbance curves of harmine, harmaline, harmol and harmalol (depending on pH and wavelenght) are discussed in detail in the following paper:

Douglas, KENNETH T., et al. "Ionization processes of some harmala alkaloids." Molecular Pharmacology 23.3 (1983): 614-618.

I would provide more information, references and suggestions, if needed. I am not familiar with the correct editing rules here so I would be happy for anyone to improve this part of the article. Ltinka (talk) 13:00, 23 August 2023 (UTC)