Concentration percentages given come from different studies of alkaloid concentrations in Mitragyna speciosa– Kratom leaf. Some of the alkaloids given in this list still need to be studied more specifically in order to determine their potential activity.
Ajmalicine (Raubasine): Cerebrocirculant, antiaggregant, anti-adrenergic (at alpha-1), sedative, anticonvulsant, smooth muscle relaxer. Also found in Rauwolfia serpentina.
Ciliaphylline: antitussive, analgesic. < 1% of total alkaloid content found in Kratom leaf.
Corynantheidine: μ -opioid antagonist, also found in Yohimbe. < 1% of total alkaloid content found in Kratom leaf.
Corynoxeine: Calcium channel blocker. < 1% of total alkaloid content found in Kratom leaf.
Corynoxine A and B: Dopamine mediating anti-locomotives. < 1% of total alkaloid content found in Kratom leaf.
Epicatechin: Antioxidant, antiaggregant, antibacterial, antidiabetic,
antihepatitic, anti-inflammatory, anti-leukemic, antimutagenic, antiperoxidant,
antiviral, potential cancer preventative, alpha-amylase inhibitor. Also found in dark chocolate.
9-Hydroxycorynantheidine: Partial opioid agonist
7-hydroxymitragynine: Analgesic, antitussive, antidiarrheal; primary
psychoactive in Kratom, Roughly 2% of total alkaloid content found in Kratom leaf.
Isomitraphylline: Immunostimulant, anti-leukemic. < 1% of total alkaloid content found in Kratom leaf.
Isomitrafoline: < 1% of total alkaloid content found in Kratom leaf.
Isorhynchophylline: Immunostimulant. < 1% of total alkaloid content found in Kratom leaf.
Isospeciofoline: < 1% of total alkaloid content found in Kratom leaf.
Mitraciliatine: < 1% of total alkaloid content found in Kratom leaf.
Mitragynine: Indole alkaloid. Analgesic, antitussive, antidiarrheal, adrenergic, antimalarial,
possible psychedelic (5-HT2A) antagonist. Roughly 66% of total alkaloid content found in Kratom leaf.
Mitragynine oxindole B. < 1% of total alkaloid content found in Kratom leaf.
Mitrafoline: < 1% of total alkaloid content found in Kratom leaf.
Mitraphylline: Oxindole alkaloid. Vasodilator, antihypertensive, muscle relaxer, diuretic, antiamnesic, anti-leukemic, possible immunostimulant. <1% of total alkaloid contents in Kratom leaf.
Paynantheine: Indole alkaloid. Smooth muscle relaxer. 8.6% to 9% of total alkaloid contents in Kratom leaf.
Rhynchophylline: Vasodilator, antihypertensive, calcium channel blocker,
antiaggregant, anti-inflammatory, antipyretic, anti-arrhythmic, antithelmintic. < 1% of total alkaloid content found in Kratom leaf.
Speciociliatine: Weak opioid agonist. 0.8% to 1% of total alkaloid content of Kratom leaf, unique to Kratom.
Speciogynine: Smooth muscle relaxer. 6.6% to 7% of total alkaloid contents of Kratom leaf.
Speciophylline: Indole alkaloid. Anti-leukemic. <1% of total alkaloid contents of Kratom leaf.
Tetrahydroalstonine: Hypoglycemic, anti-adrenergic (at alpha-2)
Mitragyna speciosa Kratom alkaloid content varies quantitatively from geographical location, and from month to month, at different leaf harvest times, which has lead some teams (Shellard et al. in the 1970s) to conclude that there may be different geographical variants within the same species.
The Chelsea College Pharmacognosy Research Laboratories collected thirty samples of Kratom from Thailand, Malaysia, and Papua New Guinea between 1961 and 1970. All contained mitragynine, but also proved to have considerable variation in the alkaloid makeup. For red and green/ white leaved plants of Thailand, the most common alkaloidal profile was mitragynine, speciogynine, speciociliatine, paynantheine, traces of ajmalicine, traces of (C9) methoxy-oxindoles, and traces of other indoles.
Yet other Thai plants contained distinct alkaloidal profiles, some with many more alkaloids. In the Malay specimens, one contained mitragynine, speciofoline, and other indoles and oxindoles, while others contained mitragynine, ajmalicine, speciogynine, speciociliatine, paynantheine, traces of indoles, and (C9) methoxy-oxindoles. Specimens from Papua New Guinea contained mitragynine, speciogynine, speciociliatine, paynantheine, specionoxeine, and isospecionoxeine.
Prior to the late 1990’s, nearly all chemical studies of Kratom activity focused on mitragynine with the assumption thatmitragynine was the main active alkaloid. With 7-hydroxymitragynine now clearly identified out as the principal psychoactive alkaloid in Kratom, many elements of these studies need to be revised.
Takayama et al. also found that Thai and Malay Kratom had the alkaloids mitragynine, speciogynine, speciociliatine, paynantheine and 7-hydroxymitragynine in common. In both Thai and Malay samples, mitragynine was the most abundant alkaloid, yet it made up 66% of the total alkaloid in the Thai Kratom sample, while it made up only 12% of the alkaloids from the Malaysian sample. The Malay Kratom sample had mitragynaline and pinoresinol as major components, as well asmitralactonal, mitrasulgynine and 3,4,5,6-tetradehydromitragynine.
Working with the leaves of Malay Mitragyna Kratom plants, the Houghton and Said team found 4 new types of indole alkaloids (corynantheidaline, corynantheidalinic acid, mitragynaline and mitragynalinic acid), in very young leaves.
These new alkaloids were reported as having an unusual skeleton, with a carbon function at the C14 position (in comparison with previously known monoterpenoid indoles), but another research team, lead by Pr. Takayama, later revised the structure of the mitragynaline and corynantheidaline alkaloids, showing that there was actually no substitution on the 14 position.
The variety of alkaloids discovered in diverse Kratom samples to this day still calls for further studies and experimentation, investigating their specific activity, effects and potential applications.
Through its makeup and tradition of use, it is clear Mitragyna speciosa Kratom is much more than a simple opioid-like narcotic and mild stimulant. Many of the secondary chemicals found in Mitragyna speciosa Kratom are present in small yet appreciable quantities, and their synergetic role and activity in the general pharmacology of Mitragyna speciosa Kratom is not yet fully understood, as thorough research has only just begun.