Sodium nitroprusside triggers mitragynine biosynthesis in Kratom

Kratom or Mitragyna speciosa (Korth.)Havil. belongs to the Rubiaceae family. The psychoactive compounds, accumulated in this plant, such as mitragynine and its derivative like 7-hydroxy-7H-mitragynine are opioid agonists [1]. It exhibited numerous pharmacological activities e.g. analgesic, antidiarrheal, antidepressant, and muscle relaxant, for instance [2]. For this reason, mitragynine is a molecule of interest and being a candidate for an oral analgesic drug. Elicitation is a powerful technique to increase secondary metabolite in the plants. We aimed to study the effect of sodium nitroprusside (SNP) on mitragynine production in kratom. The present study, we elicited the in vitro kratom culture with SNP, a nitric oxide (NO) donor. Plant elicited with 1 mM SNP for 48 h increased secologanin production, not alter mitragynine production significantly. Treatment plants with SNP together with CPTIO, a NO scavenger revealed the suppression of secologanin biosynthesis. In addition, treatment with 1 mM nifedipine (a calcium channel blocker) inhibited secologanin synthesis significantly. This evidence suggested that calcium channel involved in the NO response. Transcription profile analysis of gene-associated with mitragynine biosynthesis indicated that the mRNA levels were increased when elicited with SNP and reduced in plant treated with SNP and CPTIO or nifedipine. The reason that SNP did not increase the amount of mitragynine because of the limitation of tryptamine in the plant [3]. In conclusion, NO released from SNP could promote mitragynine biosynthesis by triggering their biosynthetic genes and increase secologanin production.

• References

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