It is common knowledge that the most potent opioid alkaloids in Kratom are 7-hydroxymitragynine and Mitragynine, and usually customers who are researching Kratom products only look at the concentrations for these two alkaloids. In-fact, lab tests almost never test for any other alkaloids in Kratom besides Mitragynine and 7-hydroxymitragynine.
However, Kratom actually has around 50 alkaloids, with new alkaloids being discovered all the time. Further, some of these other alkaloids are abundant enough to be considered primary alkaloids, and these lesser known primary alkaloids play a critical role in Kratom’s pharmacology and medicinal benefits.
The below chart from the scientific study ‘Analysis of Mitragynine and Other Alkaloids in Mitragyna speciosa Plants Using Supercritical Fluid Chromatography‘ shows the relative fractions of the most abundant alkaloids in Kratom.
As can be seen, Mitragynine is by far the most abundant alkaloid in Kratom, but there are actually 5 other alkaloids which are more abundant than 7-hydroxymitragynine.
The two most abundant alkaloids besides Mitragynine are Corynoxine B and Speciociliatine. Notably, Speciociliatine is an opioid agonist, albeit weaker than Mitragynine, but considering the abundance of Speciociliatine in Kratom, it is likely that Speciociliatine plays an important role in Kratom’s opioid effects.
As for Corynoxine B, it is considered a dopamine mediating anti-locomotive, which in other words means it has a sedative effect. Based on this, it is likely that Corynoxine B plays an important role in how sedating a particular strain of Kratom is.
After that the next most abundant alkaloid is Paynantheine, and Paynantheine is a smooth muscle relaxer. Therefore, Paynantheine likely plays a critical role in Kratom’s pain relieving effects, especially for pain where muscle tension is an issue. Indeed, Kratom would probably be nowhere near as effective without Paynantheine. Likewise, Isopaynantheine is also present in Kratom in a similar concentration to 7-hydroxymitragynine, and it likely has important muscle relaxing properties as well.
Finally, Speciogynine is also quite abundant in Kratom, and like Paynantheine it is also a smooth muscle relaxer, and contributes to Kratom’s analgesic effects.
Thus, there are several other alkaloids in Kratom which can be considered primary alkaloids, since they are present in concentrations even higher than 7-hydroxymitragynine, and these alkaloids have critical benefits including smooth muscle relaxation, opioid effects, and sedation.
Zooming out, the other 40+ alkaloids in Kratom which are present in trace amounts also have important effects and benefits, it would just require a book rather than an article to discuss them all in-depth. The main point is that Kratom is not simply Mitragynine and 7-hydroxymitragynine, but many other alkaloids play an important role in Kratom’s effects.
On a final note, this data makes it clear that natural/full spectrum Kratom has far more medicinal properties than Kratom extract isolates.