quick and dirty LC/MS analysis of 2 commercial products

Hello! For starters I feel obliged to say that I am neither a kratom expert nor a botanist. However I do hold advanced degrees in organic chemistry which I feel entitle me to have performed the following analysis. I found the results interesting so I thought I would share.

Background

I am a newbie to kratom and recently purchased 250g each of Green Malay and Red Borneo from fresh-kratom.us. I like to know what I’m putting in my body, and I read that people can have varying responses from one strain to the next so I was curious to answer the following questions:

1. What is the alkaloid content of these two samples, specifically of the "active ingredients" mitragynine and 7-hydroxymitragynine?
2. How do the two strains compare to each other - should I expect any difference in effects between the two?

I happen to spend most of the day in a place with loads of fancy science machines. I have easy access to LC/MS instruments, which are extremely useful for plant extract analysis. I found this article which gave a very basic extraction procedure as well as reference UV/vis spectra of mitragynine and related compounds.

I felt a slight pang of guilt for doing this on the clock, so to mentally let myself off the hook I allowed myself a grand total of 15 minutes bench time and 15 cents of lab consumables to perform this analysis. Therefore this is hasty and incomplete.

Protocol

1. Took 50mg powdered dry leaf material of each sample and added 1mL of 80% methanol, 20% water in a 1.5mL Eppendorf tube. Vortexed to suspend as much as possible.
2. Sonicated for 1h
3. Allowed to stand at room temperature for 24h
4. Centrifuged at 15000rpm for 3 min to sediment plant material
5. Transferred the dark green supernatant to a fresh 1.5mL Eppendorf tube, then diluted 1:10 (50uL + 450uL methanol)
6. Filtered through a 0.2 micron filter
7. Ran LC/MS (5uL injection) using an Agilent 1200 series instrument equipped with a DAD UV detector, single quadrupole mass spec (ESI ionization, pos/neg fast polarity switching), and evaporative light scattering detector (ELSD)

Results

Here is an overlay of the UV chromatograms from both strain extracts as observed at 254nm. Right off the bat you can tell they look very similar if not identical. The big daddy peak around 5.2 minutes appears to be mitragynine, as the mass is correct and the full UV scan overlays perfectly with the spectrum reported in the above citation. 7-hydroxymitragynine elutes earlier, around 4.6min and the peak is much smaller and less defined/separated. The background subtraction of the full UV scan didn’t work well so I didn’t overlay with the literature spectrum.

So there ya have it. In general I would say these results are consistent with what wikipedia says: mitragynine is the most abundant alkaloid present and 7-hydroxymitragynine is present in much smaller amounts. If one were to spend more than 15 minutes or 15 cents doing this kind of stuff, procuring authentic reference samples of the pure alkaloids and generating standard curves would help a lot.

TL/DR: 2 strains of kratom bought from fresh-kratom.us in Feb 2016 contain what you would expect