A minor oxindole-class alkaloid in Mitragyna speciosa leaves. Distinguished from mitragynine and the other principal kratom alkaloids by its oxindole (rather than indole) ring system.

How is corynoxine structurally different from mitragynine?

Mitragynine and most kratom alkaloids contain an indole ring system. Corynoxine contains an oxindole ring system - the indole has been oxidatively rearranged into an oxindole.

What pharmacological activity has been reported for corynoxine?

Preliminary published research has examined corynoxine as an autophagy modulator in cellular models. Mu-opioid receptor activity is not the principal focus of corynoxine pharmacology research.

How abundant is corynoxine in kratom leaf?

Generally less than 1% of total alkaloid content. Corynoxine is a minor alkaloid by mass.

Alkaloids & Chemistry

Corynoxine

At-a-glance comparison

Spec	Value
Compound class	Oxindole alkaloid (distinct from the indole core of mitragynine)
Source	Minor alkaloid in Mitragyna speciosa leaf
Typical leaf abundance	Generally less than 1% of total alkaloid content
Reported pharmacological activity	Preliminary autophagy-modulator activity in cellular models; mu-opioid receptor activity not the principal focus of published work
Distinguishing feature	Oxindole ring system rather than indole

What is corynoxine?

Corynoxine is a minor alkaloid in Mitragyna speciosa leaves, distinguished from the principal kratom alkaloids by its structural class. Mitragynine, 7-hydroxymitragynine, paynantheine, speciogynine, speciociliatine, and corynantheidine are all indole alkaloids - built around the indole ring system. Corynoxine and its close analog corynoxeine, by contrast, are oxindole alkaloids, in which the indole ring system has been oxidatively rearranged into an oxindole.

Among the kratom alkaloids, corynoxine has received less pharmacology attention than mitragynine and 7-OH. The most-cited published research on corynoxine has examined its activity in autophagy modulation in cellular models - autophagy being the cellular self-clearing process that has emerged as a target of broad biomedical research in recent years. Whether and to what extent corynoxine contributes to the in vivo pharmacological profile of orally consumed kratom material is not extensively characterized in published literature.

Common questions about corynoxine

What is corynoxine?: A minor oxindole-class alkaloid in Mitragyna speciosa leaves. Distinguished from mitragynine and the other principal kratom alkaloids by its oxindole (rather than indole) ring system.
How is corynoxine structurally different from mitragynine?: Mitragynine and most kratom alkaloids contain an indole ring system. Corynoxine contains an oxindole ring system - the indole has been oxidatively rearranged into an oxindole.
What pharmacological activity has been reported for corynoxine?: Preliminary published research has examined corynoxine as an autophagy modulator in cellular models. Mu-opioid receptor activity is not the principal focus of corynoxine pharmacology research.
How abundant is corynoxine in kratom leaf?: Generally less than 1% of total alkaloid content. Corynoxine is a minor alkaloid by mass.

References

Brown PN, Lund JA, Murch SJ. (2017). A botanical, phytochemical and ethnomedicinal review of the genus Mitragyna korth. Journal of Ethnopharmacology.
Hassan Z, Muzaimi M, Navaratnam V, et al. (2013). From kratom to mitragynine and its derivatives. Neuroscience and Biobehavioral Reviews. PMID 23206666.
Sharma A, Kamble SH, León F, et al. (2019). Simultaneous quantification of ten key Kratom alkaloids. Drug Testing and Analysis.
Chen LL, Song JX, Lu JH, et al. (2014). Corynoxine, a natural autophagy enhancer, promotes the clearance of alpha-synuclein. Neuroscience Letters.

Important safety information:

Products containing 7-hydroxymitragynine (7-OH) are sold for adult use only (21+). These statements have not been evaluated by the U.S. Food and Drug Administration. Products are not intended to diagnose, treat, cure, or prevent any disease. The FDA has raised safety concerns regarding concentrated 7-OH products; consult a qualified healthcare professional before use. Do not operate vehicles or machinery after use. Keep out of reach of children and pets. Laws vary by state, buyers are responsible for knowing applicable law.