Editing Banisteriopsis caapi (section)

===Alkaloids===
Caapi contains the following [[harmala alkaloid]]s:

*[[Harmine]], 0.31–8.43%<ref name="Callaway2005" />
*[[Harmaline]], 0.03–0.83%<ref name="Callaway2005" />
*[[Tetrahydroharmine]], 0.05–2.94%<ref name="Callaway2005" />

These alkaloids of the [[beta-Carboline|beta-carboline]] class act as [[monoamine oxidase inhibitor]] (MAOIs).<ref name="pmid19879939">{{cite journal |vauthors=Samoylenko V, Rahman MM, Tekwani BL, Tripathi LM, Wang YH, Khan SI, Khan IA, Miller LS, Joshi VC, Muhammad I |title=Banisteriopsis caapi, a unique combination of MAO inhibitory and antioxidative constituents for the activities relevant to neurodegenerative disorders and Parkinson's disease |journal=Journal of Ethnopharmacology |volume=127 |issue=2 |pages=357–67 |date=February 2010 |pmid=19879939 |pmc=2828149 |doi=10.1016/j.jep.2009.10.030 }}</ref> The MAOIs allow the primary psychoactive compound, [[N,N-dimethyltryptamine|DMT]], which is introduced from the other common ingredient in ayahuasca ''[[Psychotria viridis]]'', to be orally active.

The stems contain 0.11–0.83% beta-carbolines, with harmine and tetrahydroharmine as the major components.<ref name="Callaway2005">{{Cite journal | doi = 10.1080/02791072.2005.10399795 | last1 = Callaway | first1 = J. C. | last2 = Brito | first2 = Glacus S. | last3 = Neves | first3 = Edison S. | title = Phytochemical analyses of ''Banisteriopsis caapi'' and ''Psychotria viridis''| journal = Journal of Psychoactive Drugs | volume = 37 | issue = 2 | pages = 145–150 |date=June 2005| pmid = 16149327| s2cid = 30736017 }} {{closed access}}</ref>

Alkaloids are present in all parts of the plant.<ref name="Christian">{{cite book |last= Rätsch|first= Christian|date= 2005|title=The Encyclopedia of Psychoactive Plants: Ethnopharmacology and Its Applications|publisher= Inner Traditions/Bear|isbn=9780892819782}}</ref>