Karakin is a toxic glucoside found in several plants, principally in the berries of the New Zealand native tree Karaka (Corynocarpus laevigatus), though it has also been identified in other plants such as Corynocarpus similis, Coronilla varia, Lotus pedunculatus, and Heteropterys umbellata.Hutchins RF, Sutherland OR, Gnanasunderam C, Greenfield WJ, Williams EM, Wright HJ. Toxicity of nitro compounds from Lotus pedunculatus to grass grub (Costelytra zealandica) (Coleoptera: Scarabaeidae). J Chem Ecol. 1984 Jan;10(1):81-93. Cabalion P, Poisson J. Corynocarpus similis Hemsley, plante alimentaire et toxique de Vanuatu (ex-Nouvelles-Hebrides) [Corynocarpus similis Hemsley, dietary and toxic plant of Vanuatu (formerly New Hebrides)]. J Ethnopharmacol. 1987 Nov;21(2):189-91. Mannochio-Russo H, Nunes WDG, Almeida RF, Albernaz LC, Espindola LS, Bolzani VS. Old Meets New: Mass Spectrometry-Based Untargeted Metabolomics Reveals Unusual Larvicidal Nitropropanoyl Glycosides from the Leaves of Heteropterys umbellata. J Nat Prod. 2023 Mar 24;86(3):621-632. Karakin is the glucoside of 3-nitropropionic acid and can produce severe toxicity when consumed by humans, with symptoms including vomiting, diarrhea, muscle weakness, paralysis, confusion and convulsions. Karaka berries can however be consumed safely by some native New Zealand birds such as Kereru, and were traditionally eaten by Māori after an extensive preparation process to remove the toxin.Shaw SD, Billing T. Karaka (Corynocarpus laevigatus) toxicosis in North Island brown kiwi (Apteryx mantelli). Vet Clin North Am Exot Anim Pract. 2006 Sep;9(3):545-9. MacAskill JJ, Manley-Harris M, Field RJ. Quantification of nitropropanoyl glucosides in karaka nuts before and after treatment. Food Chem. 2015 May 15;175:543-8. Watson DJ, Evans A, Blockman M, Wiesner L. Detection of karakin poisoning using a targeted mass spectrometric workflow. S Afr Med J. 2022 Dec 1;112(12):901-903.
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