Environmental and ontogenetic control of accumulation of brachycerine, a bioactive indole alkaloid from Psychotria brachyceras

J Chem Ecol. 2004 Oct;30(10):2023-36. doi: 10.1023/b:joec.0000045592.24785.33.

Abstract

Brachycerine is a monoterpenoid indole alkaloid accumulated in Psychotria brachyceras plants (Rubiaceae). To better understand the accumulation patterns of this alkaloid, we investigated its content in different plant organs from field-grown trees, throughout the seasons, during seedling development, and in response to potential biotic factors regulating its biosynthesis. Quantification by RP-HPLC showed that aerial vegetative organs (green stems, young and old leaves) yielded similar amounts of brachycerine [0.1-0.2% dry weight (DW)]. Brachycerine was not detected in roots. In reproductive structures, the highest brachycerine amounts (0.3% DW) were found in inflorescences. Alkaloid concentration decreased in mature fruits (0.045% DW). The lowest concentration in reproductive organs was observed in quiescent seeds (0.004% DW). Apparently, brachycerine content dropped during radicle emission in germinating seeds. During seedling development, an increase in leaf content from 0.02 to 0.1% DW was observed between the stages of 2 and 14 leaves, respectively. Salicylic acid did not affect brachycerine content. A doubling of alkaloid content was observed in wounded plants, and a threefold induction occurred with jasmonic acid treatment, suggesting that brachycerine biosynthesis is regulated by jasmonate production.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cyclopentanes / metabolism
  • Cyclopentanes / pharmacology
  • Environment*
  • Germination
  • Indole Alkaloids / chemistry
  • Indole Alkaloids / metabolism*
  • Indoles / metabolism*
  • Monoterpenes / metabolism*
  • Oxylipins
  • Plant Leaves / chemistry
  • Plants, Medicinal / chemistry*
  • Rubiaceae / chemistry*
  • Salicylic Acid / metabolism
  • Salicylic Acid / pharmacology
  • Seasons

Substances

  • Cyclopentanes
  • Indole Alkaloids
  • Indoles
  • Monoterpenes
  • Oxylipins
  • brachycerine
  • jasmonic acid
  • Salicylic Acid